Department of Plant Sciences

Permanent URI for this collectionhttps://repository.chuka.ac.ke/handle/123456789/150

Browse

Now showing 1 - 19 of 19

PHENOTYPIC CHARACTERIZATION OF SELECTED LOCAL MAIZE LANDRACES FOR DROUGHT TOLERANCE BASED ON FLOWERING STRESS, AND THEIR RESISTANCE TO LARGER GRAIN BORER (Prostephanus truncatus) IN KENYA
(Chuka University, 2008-10) MUNYIRI SHELMITH WANJA
Maize is staple food in Kenya and is grown in almost all agro-ecological zones. The average maize yield in the highlands is about 3.5 t/ha while that for the arid and semi arid (ASALs) low altitude areas is less than 1.3 t/ha. Arid and semi arid areas constitute about 82% of the total land area and supports about 20% of the country’s human population. The demand for more food culminating from the population increase and the migration of people from high potential areas to semi arid lowlands has led to maize growing in marginal areas. Kenya’s ASALs are home to the very rural poor who practice subsistence farming as a livelihood. Local landraces of maize are an important livelihood resource in these areas. The objective of the study was to characterize selected Kenyan local maize landraces for drought tolerance and resistance to larger grain borer in storage. The characterization for drought tolerance was carried out using secondary traits that exhibit high heritability for drought tolerance such as grain yield, anthesis-silking interval (ASI), tassel size, ears per plant and leaf rolling. The experiment was laid out in a lattice design (unbalanced) each with sixty-four maize genotypes. A second experiment to evaluate drought tolerance was conducted for landraces that exhibited favorable tolerance characteristics. This experiment was laid out in a split plot (RCBD) design with water levels (water stressed and unstressed, at flowering) as the main plots and germplasm as the sub plots. Irrigation was withheld one week to tasseling and resumed forty days later in water stressed plots. The wellwatered plots had continuous irrigation. The field experiments were carried out at KARIMasongaleni field station in Kibwezi district, which falls under agro-ecological zone VI. Among the characters evaluated, a low ASI (1-6 days) was associated with a high level of drought tolerance and low yield losses under moisture stress. Drought stress resulted in 17% to 81% relative grain yield losses. Germplasm GBK-032419, DT/BT/1470.DT and GBK-034659 exhibited lowest grain yield losses of 28%, 22% and 17% while KTL N 70140-4, KTL N 10162- 1 and Makueni Dry Land Composite (control) exhibited high grain yield losses of 81%, 70% and 68%, respectively. However, Katumani inbred lines DT/BT/1917.DT and DG/BT/2443.DT, though exhibiting the shortest ASI of about 1 day experienced about 50% grain yield loss under moisture stress. In general, an increase in number of ears per plant, 100-seed weight, increased plant height, high shelling %, reduced leaf rolling and low ASI were associated with yield increases under water stress. Germplasm that exhibited favorable drought tolerance characteristics were CML-492, DT/BT/1917.DT, DT/BT/1470.DT, DG/BT/2443.DT, GBK044593, GBK-032419, GBK-032423, GBK-34659, KTL N 701104 and GBK-032357. The most vii susceptible germplasm (ASI between 12-17 days) were KTL N 70133-3, KTL N 10168-1, Katumani Composite B, Makueni Dry Land Composite, KTL N 10168-2, GBK-043227, GBK034711 and GBK-027054. The germplasm that exhibited drought tolerance characteristics were further evaluated for resistance to larger grain borer (LGB) damage in storage. This experiment was done at CIMMYT field laboratory-Kiboko. Samples were laid out in complete randomized design and replicated three times. Although no absolute resistance existed, most landraces exhibited higher levels of resistance to LGB than the control variety H614. The germplasm with the highest resistance level was CML-492, while GBK-043731 had the lowest level. Germplasm CML-492, DT/BT/1971.DT, DT/BT/1470.DT, DG/BT/2443.DT, GBK-044593, GBK-032419, GBK-032423, GBK-34659 and GBK-032357 exhibited tolerance to drought and also resistance to LGB relative to control H614. Katumani Composite B, though exhibiting susceptibility to drought, had a high level of resistance to LGB than most local landraces. It was concluded that some Kenyan local landraces exhibit drought tolerance characteristics and also resistance to LGB. According to factor analysis, the phenotypic characteristics evaluated for drought tolerance accounted for 68% of the total variation.
Multivariate analysis techniques reveal significant morphogenetic variability in pumpkin landraces in Kenya
(International journal of bioscience, 2018) Kiramana,James Kirimi, Isutsa,Dorcas Khasungu
Documentedinformation on naturalizedpumpkin landraces inKenyatoidentifyusefulvariabilityis insufficient. The present study assessed variability using quantitative characters of 155 accessions, with 70 and 85 from Kakamega and Nyeri regions, respectively. The accessions were grown in one farm in a completely randomized design with three replications. Analysis of variance showed significant (P<0.05) variation in all characters. Lowest andhighest variablesinmeanandrangewereleaflength/width ratioandseednumber that were0.8 and 0.4, and 837 and 4,111, respectively. Eight factors accounted for 79.4% of total variation. The highly variable factors were fruit flesh thickness, length, width and length/width ratio, size, total weight, average weight and number, as well as seed number, 100-seeds weight, length, width, and thickness. Phenotypic coefficients of variation (PCV) were slightly higher or equal to genotypic ones (GCV). High GCV and PCV, heritability and genetic gain resulted for fruit size, total fruit weight, fruits and seeds. Over 70 positive correlations in fruit size, number and seeds with total fruit weight were observed in genotypic and phenotypic variabilities. Maximum positive direct effects on total fruit weight were observed in seeds, fruit average weight, length, and size, while indirect effects were observed in fruit number, flesh thickness, length, peduncle length and days to first flower. Multivariate analysis revealed fruit size, number, total weight, and seeds were characters of great genetic variability,whichshouldbeconsideredasprimarycomponentsforachievinghighyieldsinpumpkinswhen screeningaccessionsforselectionandimprovement
PREVALENCE AND CHARACTERIZATION OF AVOCADO FRUIT FUNGAL DISEASES IN EMBU COUNTY, KENYA AND THE EFFICACY OF Aloe secundiflora CRUDE EXTRACTS IN THEIR CONTROL
(Chuka University, 2023-10) MULEI FRANCISCA MWONGELI
Avocado production has increased exponentially worldwide due to increased demand for the fruit in the food, pharmaceutical, cosmetic, and oil industries. However, avocado production faces various constraints that include post-harvest losses due to pests and diseases, which contribute about 83% of yield losses. Fungal diseases are the most prevalent and are difficult to control using cultural methods, while continuous use of chemicals can lead to pathogen resistance and have adverse effects on humans and the environment. The main objective of this study was therefore to determine the prevalence of the fungal avocado fruit diseases in Embu County, isolate and characterize the causal pathogens and test the efficacy of Aloe secundiflora (Aloe) crude extract in the management of the fungal diseases. Aloe was selected because of its wide medicinal use and local availability. A descriptive cross-sectional survey design was carried out in six purposefully selected avocado markets in the study area to assess the prevalence of fungal diseases of avocado fruit. A structured questionnaire was administered to gather information on avocado production, marketing, and management. A total of 100 respondents were interviewed. The stores and avocado bags were randomly selected. The fruits in the bags were assessed to determine the prevalence of fungal avocado diseases. Experiments were then carried out in the laboratory to isolate and characterize the pathogens. Aloe leaves were collected in the field, and phytochemical analysis of the crude extracts was done. The efficacy of the crude extract against the pathogens was tested in the laboratory using a Complete Randomized Design (CRD). The data were subjected to an analysis of variance (ANOVA) using Scientific Analysis System version 9.4 Software. Significant means were separated using LSD at p < 0.05 significant level. Results on the demographic characteristics of the respondents showed that the majority were above 30 years of age, with more women than men, and had a primary level of education. More than 50% sourced avocado fruits from their own farms and were able to identify disease symptoms themselves. The main methods of harvesting were both handpicking and hook, and the product was mainly stored in sacks. More than 40% of the respondents used chemicals to control fruit diseases. Three fungal pathogens were isolated and characterized: Colletotrichum gloeosporioides (anthracnose), Cercospora purpurea (cercospora spot), and Sphaceloma perseae (avocado scab) and their mean percentage prevalence was 29.00%, 25.98% and 31.44%, respectively. The commonly sold varieties were Hass, Fuerte, Puebla and the local varieties, with Hass being the most preferred variety. Fuerte and Puebla were the most susceptible to these diseases. There were variations in the morphological characteristics of the pathogen isolates: C. gloeosporioides had a white to grey smooth mycelia, concentric zonation and sizes ranging from 3.0 - 5.0 μm in width and 10.3 - 18.2 μm in length. Sphaceloma perseae had a white and yellow layered mycelium with sizes ranging from 3.0 - 5.0 μm in width and 10.3 - 18.2 μm in length, while C. purpurea had a leathery grey to brown conidia of 2 - 5 μm in width and 20 -34 in length. Phytochemical analysis of the aloe-ethanol extract revealed the presence of steroids, phenolics, flavonoids, saponins, and terpenoids, but phenolics were only present in the hexane extract. The mean zone of inhibition for the ethanol and hexane extract against C. gloeosporioides was 13.50 mm and 9.36 mm, respectively, while for Cercospora purpurea was 4.72 mm and 4.32 mm, respectively, but no effect on S. perseae at any concentration. Vendors should therefore be trained on proper handling of avocado fruits to reduce post-harvest losses. Aloe secundiflora extracts can be integrated with other methods of managing avocado fungal diseases to reduce over-reliance on chemical fungicides.
EFFECTS OF HARVESTING STAGE, DRYING METHOD AND PACKAGING ON COWPEA LEAF NUTRIENT COMPOSITION AND MICROBIAL GROWTH CONTAMINATION
(Chuka University, 2023-10) GITAU JANE WANJIKU
Cowpea leaf production is constrained by the short post-harvest shelf life which is associated with high moisture content. This subjects the cowpeas to quantitative, qualitative, and economic losses. Farmers lack knowledge on the best cowpea harvesting stage, drying and packaging method for quantitative and qualitative benefit. This research therefore aimed at obtaining information on the right harvesting stage that would enhance cowpea utilization by farmers as well as the most efficient and safest drying method that would reduce post- harvest losses associated with glut production during the rainy season. This study also aimed at prolonging the keeping quality of the dried cowpea leaves for use during off- season and coming up with information on the best and affordable packaging material that would ensure safety of dried cowpea leaves. The study was conducted at a farmers’ field in Tharaka Nithi County. The field experiment was laid in RCBD and replicated thrice. The analysis of drying and packaging methods on nutrient composition and microbial growth was conducted at Chuka University laboratory using CRD. Cowpeas variety M66 was used for the research and the treatments included three harvesting stages (21, 35 and 49 Days after sowing, DAS), three drying methods (open sun, solar and oven) and 3 packaging methods (aluminium foil, woven bags and kraft paper). Data collected included chlorophyll content, iron, calcium, crude fibre, beta carotene, protein and moisture content and microbial contamination. The data was subjected to ANOVA using the 9.2 edition of the Statistical Analysis System and the significant different means separated using LSD at 5%. The results showed that harvesting stage at 49 DAS significantly (p<0.05) influenced the chlorophyll content with 49 DAS recording the highest chlorophyll content in both trials followed by 35 DAS and the least at 21 DAS nm. The harvesting stage also influenced significantly p<0.05 the moisture, protein, crude fibre, beta carotene, iron and calcium content. The results showed a reduction in moisture content as the harvest days increased in both trials with the highest moisture content was observed at 21 DAS and the least at 49 DAS. The iron content of cowpea leaves was significantly (p<0.05) different at 49 DAS in both trials. In trial one and two,21 and 35 DAS were not significantly(p<0.05) different. The calcium content at 21 and 49 DAS in both trials was significantly (p≤0.05) different. The protein content was significant in all the stages of harvesting. The highest protein content in both trials was recorded at 21 DAS at 29.41% and 28.47%, respectively with 49 DAS recording the least protein content in both trials at 27.52% and 24.07%, respectively. For Beta carotene, 49 DAS recorded the least content at 7.61mg and 10.51 mg in both trials. Crude fibre content increased with the stage of harvesting. In both trials,49 DAS recorded the highest crude fibre content at 8.02mg and 5.83mg and the least fibre content recorded at 21 DAS at 2.21 mg and 2.53 mg in both trials respectively. Interaction effect of harvesting stage and drying methods showed significant (p< 0.05) difference on moisture, iron, calcium, proteins, beta carotene and crude fibre content in both trials. Oven and solar drying methods showed better nutrient and mineral retention in the three harvesting stages when compared to the open sun drying method. The combination of harvesting stage, drying method and packaging material significantly (p<0.05) influenced microbial load (bacterial and fungal). No coliforms were observed. Oven dried cowpea leaves, harvested at 49 DAS, and packaged in kraft paper resulted in the least bacterial and fungal contamination. It can be concluded that harvesting cowpea leaves at 21 and 35 DAS and drying using the oven and solar methods and packaging in kraft papers can help in reducing the post- harvest losses and ensure cowpea leaves availability in all seasons.
PHENOTYPIC CHARACTERIZATION OF SELECTED LOCAL MAIZE LANDRACES FOR DROUGHT TOLERANCE BASED ON FLOWERING STRESS, AND THEIR RESISTANCE TO LARGER GRAIN BORER (Prostephanus truncatus) IN KENYA
(Egerton University, 2008-10-01) Munyiri, S.M
Maize is staple food in Kenya and is grown in almost all agro-ecological zones. The average maize yield in the highlands is about 3.5 t/ha while that for the arid and semi arid (ASALs) low altitude areas is less than 1.3 t/ha. Arid and semi arid areas constitute about 82% of the total land area and supports about 20% of the country’s human population. The demand for more food culminating from the population increase and the migration of people from high potential areas to semi arid lowlands has led to maize growing in marginal areas. Kenya’s ASALs are home to the very rural poor who practice subsistence farming as a livelihood. Local landraces of maize are an important livelihood resource in these areas. The objective of the study was to characterize selected Kenyan local maize landraces for drought tolerance and resistance to larger grain borer in storage. The characterization for drought tolerance was carried out using secondary traits that exhibit high heritability for drought tolerance such as grain yield, anthesis-silking interval (ASI), tassel size, ears per plant and leaf rolling. The experiment was laid out in a lattice design (unbalanced) each with sixty-four maize genotypes. A second experiment to evaluate drought tolerance was conducted for landraces that exhibited favorable tolerance characteristics. This experiment was laid out in a split plot (RCBD) design with water levels (water stressed and unstressed, at flowering) as the main plots and germplasm as the sub plots. Irrigation was withheld one week to tasseling and resumed forty days later in water stressed plots. The wellwatered plots had continuous irrigation. The field experiments were carried out at KARIMasongaleni field station in Kibwezi district, which falls under agro-ecological zone VI. Among the characters evaluated, a low ASI (1-6 days) was associated with a high level of drought tolerance and low yield losses under moisture stress. Drought stress resulted in 17% to 81% relative grain yield losses. Germplasm GBK-032419, DT/BT/1470.DT and GBK-034659 exhibited lowest grain yield losses of 28%, 22% and 17% while KTL N 70140-4, KTL N 10162- 1 and Makueni Dry Land Composite (control) exhibited high grain yield losses of 81%, 70% and 68%, respectively. However, Katumani inbred lines DT/BT/1917.DT and DG/BT/2443.DT, though exhibiting the shortest ASI of about 1 day experienced about 50% grain yield loss under moisture stress. In general, an increase in number of ears per plant, 100-seed weight, increased plant height, high shelling %, reduced leaf rolling and low ASI were associated with yield increases under water stress. Germplasm that exhibited favorable drought tolerance characteristics were CML-492, DT/BT/1917.DT, DT/BT/1470.DT, DG/BT/2443.DT, GBK044593, GBK-032419, GBK-032423, GBK-34659, KTL N 701104 and GBK-032357. The most vii susceptible germplasm (ASI between 12-17 days) were KTL N 70133-3, KTL N 10168-1, Katumani Composite B, Makueni Dry Land Composite, KTL N 10168-2, GBK-043227, GBK034711 and GBK-027054. The germplasm that exhibited drought tolerance characteristics were further evaluated for resistance to larger grain borer (LGB) damage in storage. This experiment was done at CIMMYT field laboratory-Kiboko. Samples were laid out in complete randomized design and replicated three times. Although no absolute resistance existed, most landraces exhibited higher levels of resistance to LGB than the control variety H614. The germplasm with the highest resistance level was CML-492, while GBK-043731 had the lowest level. Germplasm CML-492, DT/BT/1971.DT, DT/BT/1470.DT, DG/BT/2443.DT, GBK-044593, GBK-032419, GBK-032423, GBK-34659 and GBK-032357 exhibited tolerance to drought and also resistance to LGB relative to control H614. Katumani Composite B, though exhibiting susceptibility to drought, had a high level of resistance to LGB than most local landraces. It was concluded that some Kenyan local landraces exhibit drought tolerance characteristics and also resistance to LGB. According to factor analysis, the phenotypic characteristics evaluated for drought tolerance accounted for 68% of the total variation.
PHYTOCHEMICAL ANALYSIS AND ANTIMICROBIAL ACTIVITY OF Tamarindus indica EXTRACTS AGAINST Fusarium oxysporum AND Xanthomonas campestris
(Chuka University, 2022-09) GITARI, FREDRICK
Plant pathogens are a major threat to biodiversity and food security worldwide. They cause severe losses or damage to crops, thereby significantly reducing the quality and quantity of agricultural commodities. Bacteria and fungi are known to have the highest negative impact on plant yield quality and quantity. Cultural and chemical methods are the most commonly applied methods of controlling these pathogens. However, many cultural methods are ineffective while chemicals are harmful to the environment and living organisms. Furthermore, plant pathogenic bacteria and fungi have acquired resistance against conventional pesticides. Xanthomonas campestris is a bacterial pathogen which causes common plant diseases like Bacterial Spot Disease, Black Rot and Xanthomonas Wilt in various crops. On the other hand, Fusarium oxysporum is a fungal pathogen which causes common diseases like Fusarium Wilt and Fusarium Crown Root Rot (FCRR). It is therefore important to develop new pathogen control strategies that embrace the use of plant phytochemicals. The aim of this study was first to determine the phytochemical composition of extracts obtained from different parts of Tamarindus indica and then evaluate their antimicrobial effect against Xanthomonas campestris and Fusarium oxysporum invitro. A phytochemical analysis of T. indica was carried out to establish the bioactive components present in different parts of the tree (leaves, bark, roots and pods). They were collected from the field and prepared for phytochemical extraction. A crude extract was obtained using different solvents (dichloromethane, methanol and acetone) and a qualitative analysis was carried out to establish the phytochemicals present. In the antimicrobial assay of the extract against plant pathogens, the pathogens were grown on media containing different concentrations of the extract and the antimicrobial effect was determined by observing the rate of inhibition. The SAS version 9.4 computer software was used to analyze the data. A two-way analysis of variance was carried out to determine the differences in the means at a 95% confidence level. A total of nine phytochemicals were identified from the stem, root, pods and leaves of T. indica. These were saponins, flavonoids, alkaloids, terpenoids, steroids, phenols, tannins, glycosides and resins. In acetone and methanol extracts, a total of seven phytochemicals were identified in all the T. indica extracts. Only four phytochemicals were detected in all dichloromethane extracts. The solvents produced different medicinally important phytochemicals with methanol exhibiting the highest concentrations. The antimicrobial tests of Tamarindus indica extracts obtained using the different solvents against Xanthomonas campestris were all negative. For Fusarium oxysporum, the percentage inhibition of acetone extract ranged from 71.042% (250 ppm) in the root to 13.551% (1000 ppm) in the leaf. Inhibition of dichloromethane extracts ranged from 68.811% in leaf extract at 500 ppm to 23.224% in pods at a concentration of 62.5 ppm. There was a significant difference (p < 0.05) in the percent of inhibition exhibited by methanol extracts against Fusarium oxysporum. The percent of inhibition was recorded at 86.953% in stem extract at 125 ppm and 75.169 % in root extract at 500 ppm. Tamarindus indica extracts therefore have great potential as a source of biopesticide in integrated pest management of the plant fungal pathogen Fusarium oxysporum.
PREVALENCE AND CHARACTERIZATION OF Xanthomonas campestris pv. musacearum AND EVALUATION OF BANANA GENOTYPES FOR RESISTANCE TO BANANA WILT IN THARAKA NITHI COUNTY, KENYA
(Chuka University, 2021-04-20) MOGAKA, MELKZEDEK
Banana (Musa spp.) is one of the most grown food crops in the world, and is rich in carbohydrates, vitamins and minerals. A major constraints to banana production in Tharaka Nithi County is banana Xanthomonas wilt (BXW) caused by Xanthomonas campestris p.v musacearum. The pathogen attacks photosynthetic leaves and young fruits reducing palatability and marketability. Currently, there is limited information on severity and prevalence of BXW in Tharaka Nithi County. Different strategies are used in the region to curb the wilt, including use of chemicals, as well as cutting and uprooting infected plants, although effective management of BXW is yet to be achieved. In other parts of the world, an integration of resistant cultivars with other control methods has been the most effective method for BXW management. However, data on banana varieties that are resistant to BXW in Nithi region is still limited. The objective of this study was to determine the prevalence of BXW in Nithi region, isolate and characterize the pathogen using morphological and biochemical tests and to assess local banana genotypes for resistance to BXW. The prevalence of BXW was assessed on-farm by symptoms inspection and a survey design using structured questionnaires to banana farmers in five villages (Kiang’ondu, Marima, Mitheru, Gibumbu and Giampampo). Laboratory isolation and characterization of BXW pathogen at Chuka University was arranged in Completely Randomized Design based on site of sample origin, with three replicates. Susceptibility tests were conducted under controlled green-house conditions arranged in a Randomized Complete Block Design (RCBD) with five banana varieties and one pathogen, replicated five times. Prevalence data from the questionnaire was analysed on SAS version 9.4 version using chi square t-test of association, while data on genotype susceptibility data was analysed using a general linear model on SAS version 9.4 and significant means separated using Least Significance Difference at α = 0.05. Study revealed that percentage prevalence of BXW in the studied villages was not significantly different (p > 0.05), with the highest value of 21.14% at Giampampo while Mitheru had the least value of 11.24%. Majority of the farmers (92%) were unaware of existence of BXW in the region. Morphological and biochemical tests (Catalase test, Starch hydrolysis test, Gelatine liquefaction test, Ammonia production test) revealed the banana wilt pathogen is Xanthomonas campestris pv. musaceaerum. Susceptibility of five banana varieties to Xanthomonas wilt pathogen isolate was statistically significant (p < 0.05), with Gasukari variety having the mean of 70.37% followed by Kiganda (60.74%) while Muraru had the lowest susceptibility mean of 45.19%. In terms of resistance, Muraru variety may be a good source of breeding material due to its relative resistance to BXW and is recommended for farmers in the region. This study broadens the understanding BXW prevalence in Nithi region and provides opportunities for selection of resistant banana varieties for better yields and improved food and nutritional security in the region.
EFFECTS OF EARTHING UP AND PRUNING SYSTEMS ON GROWTH, YIELD, POST-HARVEST QUALITIES AND NET ECONOMIC BENEFIT OF TOMATO (Solanum lycopersicum)
(Chuka University, 2020-12) KETER, ISAIAH KIPROP
Tomato (Solanum Lycopersicum) is an important crop cultivated and consumed worldwide. It provides a wide variety of nutrients with many health-related benefits namely; confers protection against cancer, maintains healthy blood pressure and reduces blood glucose in people with diabetes. Its yields are limited by poor cultural practices such as earthing up and pruning systems. Earthing up and pruning play a major role in yield and quality determination. Although there is the potential for increasing tomato productivity through pruning and use of earthing up, there is limited knowledge on the effect of the integrated pruning and earthing up on tomato yield, quality and subsequently growth vigour. This study investigated the techniques that help improve on growth, yields and qualities of tomato to the benefit of farmers, traders, processors, and consumers. Zara F1 tomato variety was used in this study. The study was conducted over two cultivations, October 2019-January 2020 (at Horticultural Research and Demonstration Field, Chuka University) and February 2020-May 2020 (on a farm at Ndagani neighbouring the University). A split-plot experimental design, arranged in a Randomized Complete Block Design, with three replications was used in this study. The study investigated two factors i.e. pruning system (single stem, double stem, and triple stem) and earthing up (0 cm, 10 cm, 20 cm, and 30 cm). The pruning system was allocated to the main plot and earthing up to the sub-plot. Data on plant height was collected weekly throughout the entire growth period, beginning from 45 days after transplanting. Fruit yield and quality data were taken after each harvesting. Data obtained was analysed using SAS version 9.4 and significant means were separated using the Least Significant Difference at α = 0.05. The analysis of variance showed that earthing up, pruning system, and combined earthing up levels and pruning systems had a significant (p < 0.05) effect on the plant height, stem girth size, yield and net economic benefit. The single stem pruning system and earthing up to level 30 cm gave the tallest and the largest plant height and stem girth size respectively in both cultivations. The triple stem pruning system and earthing up to 30 cm had the highest total yield and net economic benefit as compared to the controls. The results from the analysis of variance for the effect of factors (earthing up and pruning system) and their combined effect showed that there was a significant (p < 0.05) effect on the average weight loss percentage and total soluble solids in both cultivations. The treatments had significant (p < 0.05) effect on the average weight loss percentage, total soluble solids and fruit firmness in both cultivations. The highest fruit weight loss percentages were recorded from single stem pruning system with no earthing up (SS0), double Stem pruning system with no earthing up (DS0) and triple Stem pruning system with no earthing up (TS0) (control). The highest fruit firmness (3.41 N mm-1 in cultivation 1 and 3.24 N mm-1 in cultivation 2) was recorded from a single stem pruning system, earthing up to 30 cm. The highest total soluble solids (TSS) percentage 6.09 % in cultivation 1 and 6.09 % in cultivation 2) were both recorded from a single stem pruning system and earthing up to 30 cm. Pruning and earthing up to 30 cm provided the best combination for improved plant growth and development. To improve nutrient uptake and partitioning, consequently the number of marketable fruits and total yield growers could consider integrating triple stem pruning system and earthing up to 30 cm. To improve post-harvest qualities (reduce weight loss, increase ripening period, improve tomato firmness and Brix value, the farmers should consider earthing up at 30 cm regardless of pruning system. Based on the benefit-cost ratio, it was observed that a combination of triple stem pruning system and earthing up to 30 cm gave a maximum profitable yield of tomatoes.
EFFECT OF POULTRY MANURE, NPK FERTILIZER AND PINCHING ON GROWTH, YIELD AND POST- HARVEST QUALITY OF BUTTERNUT (Cucurbita moschata) VARIETIES
(Chuka University, 2020-12) Njiru, Rachael Wambui
Butternut (Cucurbita moschata) is an important tropical fruit vegetable grown worldwide for household food security and nutrition. Butternut is widely gaining acceptance because of its nutritional value, early maturity, long shelf-life and its adaptability to a wide range of climatic conditions and farming systems. Furthermore, it is a multipurpose vegetable crop, making the crop a good alternative source of nutrition to the low income and vulnerable population. Currently its demand outweighs its supply due to low production attributed to several production constraints including poor agronomic practices such as suboptimal application of fertilizers, few female flowers, lack of appropriate pinching practices aimed at improving the number of female flowers and pests and diseases. This study aimed at determining the effect of fertilizer application and pinching on the growth, yield and post–harvest quality of butternut. The study was conducted in two trials between 2019 and 2020, i.e., Chuka University Horticultural demonstration field (Trial I) and a farmer’s field within Karingani ward in the outskirts of the University (Trial II). A 2×3×5 factorial experiment laid down in Randomised Complete Block Design was used. The treatments included fertilizers at five levels (0, 5 and 10 tonnes/ha of poultry manure, 100 and 200 Kg/ha of NPK 17:17:17), pinching at 3 levels (0, 4th node and 6th node) and two butternut varieties (Waltham and Atlas F1). Data was collected on the number of branches per plant, number of leaves per plant, number of flowers, vine length, leaf area, fruit yield, fruit mineral nutrients (Ca, Mg, Mn, Cu, Fe and P) content, fruit firmness and total soluble solids. Data obtained was subjected to analysis of variance using the SAS software version 9.4 and the significantly different means were separated using the Least Significant Difference at 5% probability level. There was significant effect of each factor and their combined effect (treatments; p < 0.05) on most of the studied variables and at different growth stages. Application of poultry manure at 10 tonnes/ha resulted to higher number of branches, leaves and flowers, longer vines, bigger leaf area, higher total soluble solids (TSS), firmer fruits, higher fruit mineral elements and fruit yield compared to NPK fertilizer and the control (no application of fertilizer). Pinching at 4th node produced a higher number of branches and leaves and flowers larger leaf area, higher TSS and fruit mineral elements, firmer fruits and higher fruit yield compared to pinching at 6th node and no pinching. The two butternut varieties performed significantly different (p = 0.0001), with an average fruit yield of 8.12 and 16.85 tonnes/ha for Waltham and Atlas F1 in Trial I and II, respectively. In regard to treatment effect, treatment V2P4M2 gave the highest butternut fruit yield of 30.98 tonnes/ha and 31.40 tonnes/ha in Trial I and Trial II, while treatment V1P00 gave the lowest butternut fruit yield of 1.29 tonnes/ha and 1.60 tonnes/ha in trial I and trial II, respectively. This study also aimed at optimising the input variables using Box-Behnken design (BBD), which revealed that the optimal level of 33 Kg/ha (Waltham) and 505 Kg/ha (Atlas F1) of NPK, and 7635 Kg/ha (Waltham) and 8102 Kg/ha (Atlas F1) poultry manure and pinching 3rd node will lead to optimal butternut fruit yield. The study demonstrated that BBD can serve as an inexpensive tool in optimization of the butternut fruit production. This study showed that appropriate agronomic practices can greatly improve butternut fruit yield. The study revealed that application of poultry manure can improve fruit quality and thus help improve nutrition. The study recommends application of 10 tonnes/ha of poultry manure and pinching at 4th node for sustainable butternut production. The study also recommends further field studies to validate the BBD predicted findings.
EFFECT OF SOURCE AND RATE OF LIVESTOCK MANURE ON GROWTH, YIELD, QUALITY AND NET ECONOMIC BENEFIT OF OKRA (Abelmoschus esculentus (L.) Moench.)
(Chuka University, 2020-12) Kamunyu, Deborah Ncuuri
Okra is a vegetable belonging to Malvaceae family mainly grown for its pods which are used fresh, canned or dried and ground as powder. Okra farmers use inorganic fertilizers which are expensive, increasing the cost of production, they result to water pollution, increases the soil acidity, which affects soil nutrients availability and uptake as well as reducing microbial activity and making production unsustainable for small scale farmers. Organic manure improve soil physical, chemical and biological properties, and are environmental friendly. However, farmers have limited information on the utilization of these organic manure sources on growth yield, quality and net economic benefit of okra. A study was conducted to determine the effects of rate cattle, goat and poultry manure on okra growth, yield, quality and net economic benefit at KALRO-Kandara Centre in Murang’a County between 2018 and 2019. The experiment was laid out in randomized complete block design with three replications for two cultivations. There were 10 treatments, i.e., 0, 3, 6 and 7 ton ha-1 for cattle and goat manure, and 0, 3, 5 and 7 tons ha-1 poultry manure. The manure treatments were applied before planting and okra variety Pusa Sawani was used during the experiment. Data collected included growth characteristics (number of leaves, plant height, number of branches, total biomass and the crop stand at the end of growth season), yield characteristics (number of pods per plant, total fresh pod yield and total dry pod weight) and quality characteristics mainly total soluble solids (TSS). Data collected was subjected to analysis of variance using SAS statistical software version 9.4 and significantly different means were separated using LSD at α = 0.05. The results showed that there was significant effect of treatments (p < 0.05) on growth, yield, quality and net economic benefit of okra. Poultry manure at the rate of 5t ha-1 recorded best growth characteristics and yield while control the least. Goat manure at the rate of 6 tons ha-1 recorded the highest total soluble solids, hence, produced pods of the highest quality of 3.18°Brix and 3.21°Brix for Trial 1 and Trial 2, respectively, whereas the control produced pods of lowest quality of 2.31°Brix and 2.34°Brix for Trial 1 and Trial 2, respectively. Cattle manure at the rate of 6 tons ha-1 recorded the best net economic benefit of Ksh. 700,267 in Trial 1 and Ksh. 694,320 in Trial 2, while the control gave minimal returns of Ksh. 69,158 in Trial 1 and Ksh. 64,320 in Trial 2. This indicates an increase of net economic benefit of Ksh. 631,109 in Trial 1 and Ksh. 630,000 in Trial 2 for cattle manure compared to the control. The results of this study clearly indicate that in okra production, application of different types of animal organic manure can improve the productivity of the okra. The study recommends application of 5 tons ha-1 poultry manure, or 6 tons ha-1 of goat or cattle manure for best growth, yield, quality and net economic benefit of okra.
EFFECT OF RATE AND TIME OF PHOSPHOROUS APPLICATION AND PLANTING DENSITY ON GROWTH AND YIELD OF GROUNDNUT (Arachis hypogaea)
(Chuka University, 2020-12) Ngari, Ann Wanjue
Groundnut is the fourth most important source of edible oil and the third most important source of vegetable protein in the world. Despite its demands outweighing its supply, productivity remain low due to lack of commensurate recommendations on good agronomic practices. Groundnut yields are relatively very low in Kenya compared to other countries. The world average yields of groundnuts stand at 1447 Kg/ha, while in Asia is 1798 Kg/ha, in Nigeria and most part of West Africa is 930 Kg/ha, South Africa 2000 Kg/ha, and in Kenya is 575 Kg/ha .This is attributed to poor agronomic practices and low soil fertility, with phosphorous (P) being the most limiting factor. This study aimed at determining the effect of rate and time of phosphorous application, and planting densities on growth and yield of groundnuts. The study was conducted in two locations, Chuka University Horticultural Demonstration Farm and Kenya Agricultural and Livestock Organisation, Embu, Kenya between April and August 2018. The study used a 2 x 3 x 3 factorial experiment laid out in a Randomized Complete Block Design with three replications. There were three factors; P application rates (0, 30, and 60 Kg/ha), time of P application (at sowing, and 14 days after sowing), and planting densities (148,149; 213,331 and 333,334 plants per ha). Data on crop emergence, days to 50% flowering, plant height, days to physiological maturity, number of kernels per pod, number of empty pods and yield of groundnuts was collected. Data collected was subjected to analysis of variance using Statistical Analysis Software version 9.4. Significant means were separated using Least Significance Difference at 5% probability level. The results of the study showed that rate and timeof phosphorous application and planting densities had a significant effect (p < 0.05) on both growth and yield of groundnuts. Application of 30 Kg/ha of P at sowing with a plant density of 333,334 (30 cm by 10 cm) plants per ha gave the highest germination percentage, fewer days to flowering of groundnuts and consequently fewer days to physiological maturity. Contrary, application of 60 Kg/ha of phosporous at sowing with a plant density of 148,149 (45 cm by 15 cm) resulted to low germination percentage of the groundnuts. On the other hand, application of 60 Kg/ha of P at 14 days after sowing at plant density of 148,149 plants per ha prolonged the growth period of the groundnuts. Application of 0 Kg/ha of P at a plant density of 333,334 plants per hectare resulted in faster maturity but with lower yields. Application of 60 Kg/ha of Phosphorous applied at sowing and at a plant density of 148,149 plants per hectare gave the highest plant heights. The highest kernel yield obtained was 1,659.90 Kg per hectare, which was obtained by applying 30 Kg/ha of P applied at sowing with a plant density of 333,334 plants per hectare. The study showed that use of appropriate agronomic practices can led to sustainable groundnut production, thus ensuring food security and improved farmers income. The study recommends spacing of 30 x 10 cm and application of 30 Kg/ha of Phosphorous at sowing for sustainable groundnuts production in the study area and within similar agro-ecological zones.
Potential of orange-fleshed sweet potato in increasing vitamin A dietary intake in up to 60-month-old children in Laikipia, Kenya
(University of Nairobi, 2010-07) Kiharason, Jedidah Wanjiku
Developing countries, more so those in sub-Saharan Africa, are having to grapple with high prevalence of vitamin A deficiency. Food based approaches are being recommended as the sustainable interventions. In Kenya, orange-fleshed sweet potatoes are being recommended as one such food. This study was therefore designed to assess the potential of orange-fleshed sweet potato to improve vitamin A intake by children 25-60 months old in Rumuruti division of Laikipia district, Kenya. , Using a semi-structured questionnaire, a cross-sectional survey was carried out among 227 mothers with the target children. The situation of vitamin A deficiency was assessed using one biological and five of a composite of demographic and ecological indicators. The extent of production and consumption of sweet potato by households were also assessed. A 24-hour recall was used on a sub-sample of 32 mothers to determine dietary intake of vitamin A by the children. A focus group discussion was used to determine awareness about night blindness and its local term. As a sub-clinical indicator for vitamin A deficiency, night blindness was carried out on only 4.8% of the children; the rest had received vitamin A supplementation within the last six months. Data was coded, entered, recoded and analyzed using MS Excel, Vitamin A Intake Calculator, SPSS and Epi-Info. None of the few children assessed showed any night blindness. However, demographic and ecological indicators indicated that the children were at risk of vitamin A deficiency: 86% households were surviving on less than one dollar per person per day and less than 75% of the children were consuming vitamin A-rich foods for more than 3 days in a xii week. The results indicated that 68.7% of the children had inadequate dietary intake of vitamin A in the last 24 hours. Of this group, the 25-36 months old group had consumed on average 60.8% and the 37-60 months old group, 62.7% of their RDAs. The study established that 42% households were growing and consuming mainly whitefleshed sweet potato varieties but only 24.2% had consumed sweet potatoes in the last 7 days; only 3% had consumed for at least 3 days in the week. No child had consumed sweet potato in the last 24 hours. Potential for contribution of sweet potato to vitamin A intake by children was obtained through calculation, by assuming that an average child consumed lOOg of orange-fleshed sweet potato once a day. With the consumption, the RDA for vitamin A would be met from consumption of sweet potato alone. The children within the age of 25-36 months old would be required to eat 27g of the potato, and those between 37-60 months old would require 35g of the sweet potato to meet their RDA for vitamin A. The study concluded that sweet potatoes are a familiar and acceptable food in Rumuruti, but their contribution to vitamin A intake is minimal. Without vitamin A capsule supplementation, up. to 68% of the children are at risle of VAD. However, inclusion of orange-fleshed sweet potato in their daily diets would easily meet their vitamin A RDAs and there would be no need for the vitamin A capsule administration.
Efficacy of Neem, Tithonia And Tephrosia Leaf Extracts in Management of Root-Knot Nematodes in French Beans(Phaseolus Vulgaris L.) in Tharaka Nithi County, Kenya
(Chuka University, 2019-09) Njenga, Joshua Kinene
Agricultural production within the smallholder farming sector of East Africa is constrained by numerous factors including parasitic nematodes.Existing control measures involving applications of chemical nematicides are not viable in the medium to long term due to environmental concerns relating to their toxic residues. There is therefore a need to develop alternative control options for integrated parasitic nematode management that will promote soil eco health and reduce parasitic nematode densities. Meloidogyne spp is a major problem in Frenchbeans (Phaseolus vulgaris L.) productionsystems. In the search for alternatives to synthetic control of nematodes, a study was conducted at Chuka University Horticultural Demonstration Farm to determine the phytochemicalconstituents and nematicidal effects of crude extracts of Neem, Tithonia and Tephrosia on the control of root-knot nematodes in Frenchbeans. Crude extracts were subjected to phytochemical screening for the detection of various bioactive constituents. Constituents in Neem were alkaloids and saponins, In the invitro experiment the LC50 value of each extract was determined by assessing the mortality of juveniles and egg hatch (in the range of 5–95%) after 24, 48 and 72 hr for seven days. In a lath house pot and field experiments to determine the efficacy of the crude extract application on Frenchbeans root-knot nematodes, the Fenchbeans were planted on nematode infested soils and data on growth, development and yield components was collected. In the lath-house 5 kg pots were filled with steam-sterilized soil and infested with second stage juveniles of Meloidogyne spp.Similarly in the field experiment the planting holes were inoculated with second stage juveniles of Meloidogyne spp. The data collected was subjected to analysis of variance and significantly different means were separated using Tukey‟s Studentized Range Test at P≤0.05. In the phytochemical analysis Tithonia extracts showed the presence of alkaloids and flavonoids while Tephrosia only showed the presence of flavonoids. In invitro study, comparison between LC50 values of the extracts indicated that Neem and Tithonia at 100ml/l were the most effective on the mortality of juveniles and immobilized more than 80% of the juveniles treated. On egg hatching Neem extracts at 100ml/l were the most effective with over 90% inhibition. Among extracts treatments evaluated, crude leaves extracts obtained from Tephrosia at 100ml/l inhibited the greatest egg hatching at 0.8 eggs. Oxymyl (positive synthetic control) inhibited the greatest hatching among the treatments at 0.2 eggs. From the study the greatest egg hatching was observed in in the untreated controls at 5.5 eggs. Among the extracts evaluated, maximum mortality was recorded with Neem at 100 ml/l at 12.2 juveniles. Oxymyl inhibitory effects was recorded at 9.4 juveniles while the least inhibitory effects were observed in the untreated control at 4.3 juveniles. In both lath-house and field studies crude extract treated plots when compared to the positive control significantly had higher number of pods and pod weight. From the study it was observed that the untreated control treatment attained the least pods weight of 24.9 and 28.0 in Trials I and Trials II respectively. Neem at 50ml/l attained the highest average mean pods weight of 50.9 in both Trials I and Trials II .Oxymyl attained an average weight of 48.7 and 49.3 in Trials I and Trials II respectively. Untreated control recorded the least mean number of pods at 9.4 and 9.5 pods respectively in Trials I and Trials II. Neem at 100 ml/l attained the highest average mean number of pods at 17.4 and 17.6 pods respectively in Trials I and Trials II. (positive control) attained 15.3 and 15.5 pods respectively in Trials I and Trials II.BothLath house and field experiments indicated that the crude extracts tested had varying effects, with the majority of them reducing galling on Frenchbeans. The Neem extracts treatments had the lowest mean galling index followed by Tithonia.There was a significant (P ≤ 0.05) difference ingalling indices and yield between the leaves extract treatments and the control in both field and lath house pot Trialss. Root-knot nematode galling indices were highest in the untreated controlat 10a clear indication that the crude extracts suppressed the root-knot nematodes. There was however no significant difference between galling efficacies of crude extracts and Oxamyl in the lath house pot experiment. Once adopted, this integrated approach will result in increased yields and income to smallholder farmers. The crude extracts are affordable, easy to apply as well as environment friendly and hence sustainable over a long period of lime.
Effects of Goat Manure-Based Vermicompost on Soil Chemical Properties, Growth and Yield of Garlic in Meru South and Manyatta Sub Counties, Kenya
(Chuka University, 2019-09) Gichaba, Vincent Makini
Garlic (Allium sativum L.) is a bulb vegetable that is gaining prominence among small-scale and commercial farmers in Eastern Kenya due to its reported high returns and the readily available market. It is used as food and for medicinal purposes. Most of farmers growing garlic in Kenya, apply chemical fertilizers alone during the growth of this crop. Overutilization of chemical fertilizers has caused several adverse effects to the environment and human health, besides being costly hence limiting optimization of garlic production. Moreover, there is increase in the number of customers preferring organically produced agricultural products. This study aimed to determine the effects of different rates of goat manure-based vermicompost on soil chemical properties, growth and yield of garlic. The study was conducted in PCEA Nkio secondary school farm and KALRO Embu horticultural field in 2018 to 2019. The experiment was laid out in a randomized complete block design and replicated three times. The treatments consisted of goat manure-based vermicompost which was applied at five levels (Control treatment (0), 5, 10, 20 and 30 t ha-1), inorganic fertilizer (NPK 17-17-17) at the recommended rate of 200 Kg ha-1 and goat manure (30 t ha-1). Data collected included soil pH, total nitrogen, available phosphorous, exchangeable potassium, plant height, number of leaves, stem diameter, leaf length, leaf width, bulb fresh weight, bulb diameter, bulb length, bulb dry weight, number of cloves per bulb and bulb yield per hectare. The data obtained were subjected to ANOVA using SAS and significantly different means were separated using least significance difference at α = 0.05. Application of 30 t ha-1 goat manure-based vermicompost showed significantly (p < 0.05) higher soil pH, total N, available P and exchangeable K compared to control treatment at Chuka and Embu. Application of 30 t ha-1 goat manure-based vermicompost showed significantly (p < 0.05) higher plant height, number of leaves, stem diameter, leaf length and leaf width than control treatment at Chuka and Embu. Application of 30 t ha-1 goat manure-based vermicompost showed significantly (p < 0.05) higher bulb fresh weight, bulb diameter, bulb length, number of cloves per bulb, bulb dry weight and bulb yield per hectare than control treatment at Chuka. A similar trend was observed in Embu where goat manure-based vermicompost gave significantly (p < 0.05) higher bulb fresh weight, bulb diameter, bulb length, number of cloves per bulb, bulb dry weight and bulb yield per hectare compared to control treatment. Hence the most appropriate recommended rate of application is 30 t ha-1 of goat manure-based vermicompost in the organic production of garlic. This study, therefore, provides valuable information on the utilization of goat manure-based vermicompost in organic production of garlic.
Maize Performance and Soil Moisture Retention Under Inoculated Cowpeas Intercrop in Meru and Tharaka Nithi Counties
(Chuka University, 2019-09) Kirimi, Ian Mwenda
Agriculture is the main source of livelihood in Kenya with maize being produced in diverse environments. However, in Meru and Tharaka Nithi counties, small holder maize productivity has been diminishing due to declining soil fertility and frequent droughts. Nitrogen (N) is the principal nutrient limiting maize production hence the need for intercropping using cowpeas that are inoculated with the correct exotic bacterial strain that fix N in the soil. There was need to assess N fixation capacity using exotic bacteria by inoculating cowpeas with the correct bacterial strain. The use of N fixing legumes in intercrops with cereal crops remains a cheaper and viable option available for the resource constrained farmers to enhance soil fertility. The objective of the study was to contribute towards improved maize performance through rhizobium inoculated cowpeas intercropping. The study was conducted at two locations i.e. Kenya Agricultural Livestock Research Organization (KALRO) Igoji substation and Magutuni secondary school in Meru and Tharaka Nithi counties respectively, during the long rains of the year 2018. The experiment was laid out in a Randomized Complete Block Design and replicated three times. The treatments included maize hybrid Duma 43 variety sown as a sole crop (TI); Rhizobium inoculated variety K80, cowpeas maize intercrop (T2), cowpeas maize intercrop without inoculation (T3) and non-inoculated cowpeas K80 sole crop (T4). Data collected on maize included plant height, stem girth, canopy cover, leaf area index, light extinction coefficient and yield. Data collected on cowpea was yield. Moisture retention capacity was determined by use of a neutron probe after every week by recording the moisture from the soil in millimeters up to grain filling. Soil samples for N analysis were taken before planting and after harvesting on each treatment plot basis and the homogenous sample analyzed at University of Nairobi (UoN) soil chemistry laboratory. A general linear model was performed and data subjected to analysis of variance (ANOVA) using GENSTAT statistical package (VSN International, 2011). Means were separated using Fischer’s protected least significant difference (LSD) at 5% probability level. Results indicated that intercropped patterns under inoculated cowpeas recorded a greater leaf area index of 3.75 at Igoji and 3.16 at Magutuni. Light extinction coefficient was high in intercrops than in sole stands and ranged between 0.52 and 0.34 at Igoji and between 0.57 and 0.37 at Magutuni. Intercropped patterns intercepted more photosynthetically active radiation (PAR) (581.54 MJm-2) than pure stands (88.35 MJm-2). At kernel development stage, significantly higher soil moisture content was observed under intercropping patterns T2, (255.5±3.7mm, 253.0±1.9mm) and T3, (250.7±2.9mm, 240.5±1.3mm) than in pure maize stand T1, (245.3±4.0mm, 230.8±2.7mm) and sole cowpeas T4, (248.9±5.6mm, 233.7±3.7mm) in Igoji and Magutuni, respectively. Nitrogen fixed in T2, (0.20 g/kg, 0.18 g/kg) was higher than in T3, (0.18 g/kg, and 0.17 g/kg) and T4, (0.19 g/kg, 0.17 g/kg) at Igoji and Magutuni respectively and this was attributed to the effect of inoculation in cowpeas. The results of this study underpins the importance of intercropping maize with inoculated cowpeas as a cheaper soil fertility improvement method and as a moisture retention strategy for resource poor farmers in Meru and Tharaka Nithi counties.
Application of Response Surface Methodology in Modelling and Optimization of The Yields of Common Bean (Phaseolus Vulgaris L.) using Animal Organic Manures
(2019-09) Masai, Kimtai Leonard
The objective of design and analysis of experiments is to optimize a response which is influenced by several independent variables. In agriculture, many statistical studies have focused on investigating the effect of application of organic manure on the yield and yield components of crops. With most of these studies showing a clear positive effect of application of organic manures on the yield and yield components of various crops. However, many of these studies do not try to optimize the application of the manures for maximum productivity, but select the best treatment among the treatment range used. This is mainly due to design and analysis of experiments applied. Therefore, there is a need to apply a statistical method that would establish the effect of the application of organic manures on crop production and in addition optimize the levels of application of these manures for maximum productivity. This study aimed at application of response surface methodology for optimization of the yields of common bean (Phaseolus Vulgaris L.) using animal organic manure. The study was conducted at Chuka University Horticultural Demonstration Farm. An experiment laid down in a Randomized Complete Block Design was used. The treatments consisted of three organic manure sources (cattle manure, poultry manure and goat manure) each at three levels (0, 3 and 6 tonnes per ha). Data was collected from six weeks after sowing to physiological maturity. Data collected included the number of pods per plant grain yields at harvest. The data collected was subjected to analysis of variance and multiple Regression Analysis using the R-statistical software. The Central Composite Design was used to develop a second order polynomial model, with a goal of optimizing the multiple responses of common beans to animal organic manure. The findings indicated that there was a positive response of the goat and the poultry manure (p < 0.05) to common bean performance with the interaction of poultry and goat yielding the best results (p-value=1.51E-07)<0.05. Cattle manure did not significantly increase performance of common beans. This could be attributed to slow realise of nutrients and low N content in cattle manure. It was concluded that more use of poultry and goat would increase the yields of common beans in the area of study. The recommended levels of application of the manures in the area of study were 2.1608 t ha-1, 12.7213 t ha-1 and 4.1417 t ha-1 cattle manure, poultry manure and goat manure respectively. These are the optimum levels that would lead to maximum yield of common beans without an extra cost of input.
Health Seeking Behaviour and Lifestyle Modification Strategies of Hypertensive Patients in Imenti North Sub County, Kenya
(Chuka University, 2019-09) Mwenda, Annarita Kajuju
Globally, the prevalence of Non-Communicable diseases such as hypertension is increasing dramatically hence a burden to low income countries such as Kenya. In Kenya the prevalence of hypertension has increased gradually over the last 20 years. Cases of hypertension remains persistently high in Imenti North Sub County despite compliance to a range of drugs administered. The patient‟ knowledge of lifestyle modification and how they apply complementary strategies such as lifestyle modification strategies is not documented. The objective of the study was to determine knowledge, practice of lifestyle modification strategies and factors affecting health seeking behaviour of hypertensive patients in relation to management and control of hypertension. The research study was a cross-sectional study design. The study population consisted of hypertensive patients in Imenti North sub County of Meru County. Cluster random sampling method was used to select five (5) health facilities for study. Then purposive sampling was used to select total of 212 patients from the selected health facility proportionally. Data was collected using selfadministered questionnaires. The collected data was analysed using statistical package for social science (SPSS) for windows version 23.0. Descriptive analysis was used to obtain frequencies and percentages. The relationship between study variables was tested using Spearmans Rho correlation and bivariate logistic regression to check for the strength of the associations. The research found out that most of the patients seeking health care services in Imenti North Sub County have an average mean of 51 years and higher proportions were above 40 years of age. Majority of the patients were married and female (66.5%), and 60% respectively. An average number of participants (42%) had a secondary level of education with some having tertiary education and others non-formal education. The study findings showed that knowledge on lifestyle modification strategies used in management of hypertension was above average (68%) among the patients in this County, and this was attributed to various factors including health education given during hypertensive clinics. On practice of lifestyle modification strategies, five strategies were assessed;regular physical exercise, low salt diet, limited alcohol intake if any, cessation of smoking, and monitoring body weight gain.Each of the strategy was significantly contributing to good control of blood pressure among the participants; regular physical exercise(χ2=4.259, N=200, p=0.039), low salt diet(χ2=4.259, N=200, p=0.039), limited alcohol intake if any(χ2=23.159, N=200, p=0.000), cessation of smoking(χ2=3.705, N=200, p=0.049), and monitoring body weight gain(χ2=3.999, N=200, p=0.046). When each of the strategy was analyzed on how it influenced blood pressure control, it was evident that the patients who practiced the recommended strategies had their blood pressure controlled. Slow service delivery, long queues and the long waiting times for the laboratory results for investigations demotivated patients from seeking the health care services. The study recommends the Government of Kenya to develop policies on implementation of support groups among hypertensive patients in all hospitals and intensify campaigns on practice of lifestyle modification strategies in management of hypertension to reduce the burden on drug procurement and promote good health of her citizens. This will empower the patients on knowledge of hypertension management. The study also recommends health care providers to ensure availability of the drugs used in management of hypertension and reduce the waiting time for the patients.
Maize Performance and Soil Moisture Retention Under Inoculated Cowpeas Intercrop in Meru and Tharaka Nithi Counties
(Chuka University, 2019-09) Kirimi, Ian Mwenda
Agriculture is the main source of livelihood in Kenya with maize being produced in diverse environments. However, in Meru and Tharaka Nithi counties, small holder maize productivity has been diminishing due to declining soil fertility and frequent droughts. Nitrogen (N) is the principal nutrient limiting maize production hence the need for intercropping using cowpeas that are inoculated with the correct exotic bacterial strain that fix N in the soil. There was need to assess N fixation capacity using exotic bacteria by inoculating cowpeas with the correct bacterial strain. The use of N fixing legumes in intercrops with cereal crops remains a cheaper and viable option available for the resource constrained farmers to enhance soil fertility. The objective of the study was to contribute towards improved maize performance through rhizobium inoculated cowpeas intercropping. The study was conducted at two locations i.e. Kenya Agricultural Livestock Research Organization (KALRO) Igoji substation and Magutuni secondary school in Meru and Tharaka Nithi counties respectively, during the long rains of the year 2018. The experiment was laid out in a Randomized Complete Block Design and replicated three times. The treatments included maize hybrid Duma 43 variety sown as a sole crop (TI); Rhizobium inoculated variety K80, cowpeas maize intercrop (T2), cowpeas maize intercrop without inoculation (T3) and non-inoculated cowpeas K80 sole crop (T4). Data collected on maize included plant height, stem girth, canopy cover, leaf area index, light extinction coefficient and yield. Data collected on cowpea was yield. Moisture retention capacity was determined by use of a neutron probe after every week by recording the moisture from the soil in millimeters up to grain filling. Soil samples for N analysis were taken before planting and after harvesting on each treatment plot basis and the homogenous sample analyzed at University of Nairobi (UoN) soil chemistry laboratory. A general linear model was performed and data subjected to analysis of variance (ANOVA) using GENSTAT statistical package (VSN International, 2011). Means were separated using Fischer’s protected least significant difference (LSD) at 5% probability level. Results indicated that intercropped patterns under inoculated cowpeas recorded a greater leaf area index of 3.75 at Igoji and 3.16 at Magutuni. Light extinction coefficient was high in intercrops than in sole stands and ranged between 0.52 and 0.34 at Igoji and between 0.57 and 0.37 at Magutuni. Intercropped patterns intercepted more photosynthetically active radiation (PAR) (581.54 MJm-2) than pure stands (88.35 MJm-2). At kernel development stage, significantly higher soil moisture content was observed under intercropping patterns T2, (255.5±3.7mm, 253.0±1.9mm) and T3, (250.7±2.9mm, 240.5±1.3mm) than in pure maize stand T1, (245.3±4.0mm, 230.8±2.7mm) and sole cowpeas T4, (248.9±5.6mm, 233.7±3.7mm) in Igoji and Magutuni, respectively. Nitrogen fixed in T2, (0.20 g/kg, 0.18 g/kg) was higher than in T3, (0.18 g/kg, and 0.17 g/kg) and T4, (0.19 g/kg, 0.17 g/kg) at Igoji and Magutuni respectively and this was attributed to the effect of inoculation in cowpeas. The results of this study underpins the importance of intercropping maize with inoculated cowpeas as a cheaper soil fertility improvement method and as a moisture retention strategy for resource poor farmers in Meru and Tharaka Nithi counties.
Integrated Effect of Rhizobium Inoculation and Phosphorus Application on Soybean Growth and Yield
(Chuka University, 2019-09) Mulambula, Sioma
There has been a decline in soybean production in many parts of Kenya due to limited soil fertility, especially nitrogen and phosphorus contents. A field experiment was conducted at Chuka University Demonstration farm to determine the effect of integration of rhizobium inoculation (R) and phosphorus (P) on growth, nodulation and yields of soybeans in Meru South Sub County, Tharaka Nithi County. The experiment was laid out in a randomized complete block design (RCBD) in a split-split plot arrangement with each treatment replicated three times. The first cultivation (Trial I) was done and repeated in second cultivation (Trial II) in 2018. The aim of the experiment was to assess integration effect of R and P for sustainable soybean production in the study area. Treatments included; three rates of P (0, 20 and 30 Kg ha-1), three rates of rhizobia (0, 100 and 200 g ha-1) either applied alone or integrated and two soybean genotypes (SB19 and SB24). Triple superphosphate (0:46:0) was used as the source of the phosphorus. The soybean genotypes were assigned to the main plot with rhizobia strain in the sub-plot and phosphorus in the sub-subplots which was repeated once. Data was collected on plant height, number of pods, nodules and branches, fresh and dry nodule weight, fresh and dry shoot weight, length of root and seed yield. The data collected was subjected to analysis of variance (ANOVA) using the statistical analysis software (SAS) and significantly different means separated using Tukeys test at (p≤0.05). The results showed statistically significant difference in growth, nodulation, yield components and yields within SB19 and SB24 genotypes in both Trials at (p≤0.05). Integration of R and P at the rate of 200 g and 30 Kg ha-1 showed highest growth characteristics compared to other treatments applied. For instance, soybean plant height increased by 9.82 cm and 9.81 cm, and 10.99 cm and 11 cm at integration of 200 g and 30 Kg ha-1 compared to control for SB19 and SB24, in Trial I and II, respectively. Similarly, at integration of R and P at the rate of 200 g and 30 Kg ha-1, the dry nodule weight increased from the control treatment (0 g R and 0 Kg P per ha) to 0.81 g and 2.54 g, and 0.81 g and 2.59 g per plant for SB19 and SB24 genotypes in Trial I and II, respectively. Integration of R and P at the rate of 200 g and 30 Kg ha-1 increased grain yield by 101% and 98%, and 158% and 138%. This earned a net economic benefit of ksh. 239,496 and 192,730, and ksh. 297,930 and 239,330 for SB19 and SB24 in both Trials, respectively. Both soybean genotypes performed well in all evaluated parameters. Adoption of the integration of R and P at 200 g and 30 kg P per ha and use of either of the genotypes by farmers show greater potential of enhancing soybean productivity in Meru South Sub County.

Browse

Recent Submissions