Faculty of Agriculture and Environmental Studies (FAES)

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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.
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.
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.
Determinants of religious Tourism branding tactics in Kenya: A cross sectional study
(SAGE, 2016) Muriuki, Lemmy Mureti, Bururia,David
Shrines’ market appeal and authenticity drive religious tourism branding initiatives. Ideal packaging strate- gies further determine product performance in religious destinations. This article examined the potential contribution of market appeal and authenticity to religious tourism branding in the Kenyan Coast, Western, and Eastern regions. Multistage Cluster Sampling was used to sample 700 respondents. Surveys were con- ducted using structured interviews between February 2012 and April 2013. Questionnaires targeted commu- nities, tourists, and tourism developers. Questionnaires examined the types of shrines, utilization rate, perceived importance, and current development levels. It further assessed applicable religious tourism branding strategies within regions. Data analysis involved factor analysis, ANOVA, and t-tests. Results indi- cated that Kenyan shrines serve natural, physical, and cultural purposes, which determine their market appeal. New brands, line-extensions, and brand extensions emerged significant product branding strategies (p<0.05). Thus, it implied perceived loss of product authenticity.
Factors Influencing Adoption of Organic Farming among Farmers in Nembure Division, Embu County - Kenya
(American journal of contemporary Research, 2016-08) Njeru,Moses Kathuri
Organic farming has been mooted as an environmentally friendly farming practice in response to the growing concern over the environmental risks associated with modern agriculture. This paper examines the factors that influence adoption among farmers in Nembure division of Embu County, Kenya. Descriptive research design was used for the study. Proportionate stratified sampling was used in selecting 37% of organic farmers in the Division. All the twelve agricultural extension officers were purposively selected for the study. Pre-testing of the questionnaires was done to ensure their validity and reliability. The reliability coefficients obtained for the farmers’ and extension officers’ questionnaires were 0.79 and 0.82 respectively. The study found that women adopted organic farming practices more than men. Contrary to existing literature, age of the farmers, their level of education; labour availability and land size did not statistically influence adoption of organic farming in Nembure division.
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
Dynamics of climate change adaptations on horticultural land use practices around Mt Kenya east region
(Science PG, 2018-01-16) Kinoti,Kibetu Dickson, Jackson,Colbert Mutiso,Muthoni,Mwangi Joyce
Eastern slopes of Mount Kenya experienced widespread horticultural crop production after the establishment of Horticultural Crops Development Agency (HCDA) packing facilities within the region in the early 2000s. Favourable soils and climatic conditions triggered by growing export market demands have led to the changing patterns of agricultural land use practices in Mt. Kenya east region. The focus is now shifting to agro-diversification and land use intensification practices. The growing horticultural farming business in this region is impacting subsistence production, resource use as well as livelihood systems. This paper assesses the implications of climate change adaptation measures on household food security, gender roles and land management activities within the context of horticultural production land use practices. The findings ascertain that the region’s increasing agro-diversification activities are both coping strategies to the climate related changes and the social, political as well as economic transformations ushered in by devolution
Ensemble approach for potential habitat mapping of invasive Prosopispp.inTurkana,Kenya
(Wiley, 2018-03-03) TimNg,Wai,Cândidode ,Alexsandro ,Silva ,Oliveira , Rima,Purity,Atzberge, Clement , Immitzer,Markus
Aim:Prosopisspp.areaninvasivealienplantspeciesnativetotheAmericasandwell adapted to thrive in arid environments. In Kenya, several remote‐sensing studies conclude that the genus is well established throughout the country and is rapidly in‐ vadingnewareas.ThisresearchaimstomodelthepotentialhabitatofProsopisspp. by using an ensemble model consisting of four species distribution models. Furthermore, environmental and expert knowledge‐based variables are assessed. Location:TurkanaCounty,Kenya.Methods:Wecollectedandassessedalargenumberofenvironmentalandexpertknowl‐ edge‐based variables through variable correlation, collinearity, and bias tests. The varia‐ bleswereusedforanensemblemodelconsistingoffourspeciesdistributionmodels:(a) logisticregression,(b)maximumentropy,(c)randomforest,and(d)Bayesiannetworks.The modelswereevaluatedthroughablockcross‐validationprovidingstatisticalmeasures. Results: The best predictors for Prosopis spp. habitat are distance from water and built‐upareas,soiltype,elevation,lithology,andtemperatureseasonality.Allspecies distributionmodelsachievedhighaccuracieswhiletheensemblemodelachievedthe highest scores. Highly and moderately suitable Prosopis spp. habitat covers 6% and 9% of the study area, respectively. Main conclusions: Both ensemble and individual models predict a high risk of continued invasion,confirminglocalobservationsandconceptions.Findingsarevaluabletostake‐ holdersformanaginginvadedarea,protectingareasatrisk,andtoraiseawareness.
Effect of Applying Organic Amendments and Chick pea Integration on Soil Chemical Properties in Different Cropping Systems In Central Kenya
(Canadian Center of Science and Education, 2018-11-15) Ndukhu,O.H,Wahome,G.R.,Jensen,H.H
A study was carried out to determine the effect of applying farm yard manure (FYM) and Minjingu rock phosphate (MRP) on soil available nitrogen, phosphorus and organic carbon. The study involved field experiments under varying precipitation pattern, soil fertility levels and cropping systems over four growth seasons.Theexperimentaldesignwasarandomized completeblock(RCBD)withfourreplicationsinasplitplot arrangement where the main plots were the three cropping systems; monocropping, intercropping and crop rotation and the split plots were FYM and MRPand sampling done at crop physiological maturity. Soil pH, N, P K and C increased in the different treatments in the following order control < MRP< FYM in the three cropping systemsacrossthefourgrowingseasonsatbothsites.In maizeunderrotationwithchickpeacontrolhad;0.281% N,2.82%Cand10.68ppmP.FYM;0.554%N,4.41%Cand18.24ppmP.MRP;0.45%N,3.6%Cand41.08 ppm P.Maizechickpeaintercropcontrol;0.389%N,3.192%Cand13.4ppmP.FYM;0.531%N,4.98%Cand 41.02 ppm P. MRP; 0.49% N, 4.08% C and 50.9 ppm P. Soil under maize monocrop exhibited; control; 0.2% N, 2.59%Cand11.26ppmP.FYM;0.416%N,3.83%Cand18.01ppmP.MRP;0.28%N,3.13%Cand26.1ppmP. Almost a similar trend was observed in maize and tomato plots at both sites in all the growing seasons. Thus it can be deduced that, FYM and MRP application and legume integration in cropping systems improves soil fertility.
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.
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.
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.
Access and Utilization of Seasonal Climate Forecast Among Small Holder Farmers in Masinga Sub-County, Machakos County, Kenya
(Chuka University, 2019-09) Masesi, Gideon Kyalo
Climate change in Kenya and other East African countries is expected to manifest itself in shifts in seasons and increased frequencies of extreme weather events, such as droughts, heavy rainfall and associated flooding. As climate continues to change, seasonal forecasts will become even more crucial as one way of informing farmers of short-term weather dynamics, impending seasons of below- or above-normal rainfall and extreme rainfall events. Kenyan government has invested considerable resources into the development of understanding and technologies to meet the expected demands of its citizens for improved climate forecasts. Regrettably, many of the benefits of these investments have not yet been realized as farmers do not use this forecasts information to make agricultural sound decisions, hence benefits to the nation are considerably less than they might be otherwise. This therefore called for a study to evaluate the access and utilization of seasonal climate forecast among households in Masinga Sub County, Machakos County in Kenya. A cross-sectional survey research design was used. A systematic random sampling procedure was employed to select 274 respondents in the four sub locations of Masinga Sub County. Structured questionnaires were used to elicit required information from the respondents. Data was analyzed using both descriptive and inferential statistics. Pearson‟s correlation coefficient was utilized to establish relationship between some socioeconomic characteristics and utilization of climate forecasts. Results indicated that 82% of the respondents were able to access climate forecasts through radio, and television. Majority of the respondents indicated that their major interest was to know the start and the end of rain (63%). Radio was the major source of climate forecast (38%) with 90% of the respondents getting information from radio and 60% from television. Above 60% of the respondents indicated that the climate forecast information received from dissemination channels was inaccurate. Over 60% indicated that bulletins used very difficult and complicated language while chief “Barraza‟s” was considered to use simple language (56%). Inadequate extension officers (84%) was a limitation to access to climate forecast information. Majority of the respondents (54%) use both indigenous knowledge on climate forecast and seasonal climate forecasts, however 61% stated that they were very unsatisfied with scientific forecasts. Inaccuracy of forecasts (98%) was a key factor affecting adoption of climate forecast. Over 80% of the respondents felt that climate forecasts cover a wide area making it difficult for them to relate the climate reports to their specific local areas. It was noted that seasonal climate forecast information given by the relevant institutions are coarse thus providing little or no detail on the local characteristics of a season, and do not reflect the localized pattern of rainfall. Moreover, difficult terminologies used in climate forecasting limit their usability and usefulness to farmers and other users. Majority of farmers lack confidence in forecasts issued by KMD and perceive them to be incorrect. Most of the climate forecasts broadcasts are done at the wrong time of day, when the households were out in the fields or in their daily activities. This hinders usability of climate forecasts by the targeted groups. The study further established a significant relationship between land, income, age, education level and gender with utilization of climate forecast. Therefore, based on the major findings of this research it is recommended that, (i) climate forecasts should be downscaled into regional level and should be location specific to increase utility (ii) disseminate climate forecast through local media in local languages so that information can reach local farmers (iii) probabilistic nature of seasonal forecasts should be given with technical guidance to help farmers interpret vii easily and respond to the forecast and (iv) climate forecasts should be issued in the evening between 6.00 p.m-9.00 p.m. to reach a large audience.
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.
Spatial Variation in Adoption of Rainwater Harvesting Techniques in Meru County, Kenya.
(Chuka University, 2019-09) Mbogori, Agnes Karwitha
Rainwater harvesting has been used to address water shortage in various regions. The harvested rainwater is used for domestic purposes, irrigation and agricultural processing. Various technologies have been used over time with improvements on the old technologies as well as introduction of new technologies. Rainwater harvesting systems can be constructed with inexpensive locally available materials. People use tanks attached to roofs, caves, earth dams, underground trenches among others. However, despite the economic viability and potential of RWH techniques for improving agriculture and livelihoods, the adoption of RWH techniques by farmers is not adequate. This calls for an examination and evaluation of socio-economic factors that influence the spatial variation in the adoption of rainwater harvesting techniques in the region. A large part of Buuri Sub-County of Meru County is dry and falls in the rain shadow of Mt. Kenya with no permanent rivers and with few community-based water projects, thereby posing a great shortage of water. Like in other hot and dry parts of Kenya, rainwater harvesting has been intensively promoted in Buuri Sub-County to meet domestic needs, irrigation and other purposes. The study was guided by three objectives: (1) To investigate whether the residents of Buuri Sub-County engage in rainwater harvesting, (2) to investigate which rainwater harvesting techniques are used in Buuri Sub-County, and (3) to determine the socio-economic factors that influence the spatial variation in the adoption of rainwater harvesting techniques in the area. The study was an adoption study of descriptive survey design. The target population was 2503 homesteads in Buuri Sub-County, and a sample size of 101 respondents was selected through purposive sampling. Questionnaires were used as the instruments of data collection. Qualitative data obtained was analysed thematically. The quantitative data obtained from the study was analysed using Chi-Square tests, Pearson correlation, t-tests, one way ANOVA, and binary logistical regression. The study revealed that there was inadequate harvested rainwater despite wide adoption of rainwater harvesting (95% of the farmers), with tanks not exceeding 4000 litres highly utilised. This could be attributed to a general lack of awareness on other appropriate rainwater harvesting technologies. Additionally, the findings showed that age, academic qualification, and occupation influenced the respondents’ choices of rainwater harvesting technologies. The study revealed that the two regions chosen i.e: Kamutune and Kiirua had a slight difference in adoption of RWHTS, which was 93.5% and 97.8% respectively. Based on these findings, the study recommends the intervention of Rainwater Harvesting Techniques through infrastructural development, financial incentives, and awareness creation to popularise the adoption of alternative techniques of rainwater harvesting for commercial, domestic, and agricultural purposes by the residents of Buuri Sub-County.
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.
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.
Effect of Farm Inputs and Smallholder Farmer Characteristics on Irish Potato (Solanum Tuberosum L.) Production Technical Efficiency in Molo Sub County, Nakuru County, Kenya
(Chuka University, 2019-09) Kamau, Pauline Nyokabi
In Kenya, irish potato is the second most consumed food crop after maize. The sub-sector contributes significantly to the country’s food security and generates income and employment to many smallholder farmers. Irish potato farming is an important enterprise for smallholder farmers in Molo Sub County. Despite its significance, smallholder irish potato farmers’ production is constrained by low farm inputs technical efficiency. The national actual production of irish potato is far much below the potential production level. For maximum and sustainable irish potato production to be attained efficient use of the available farm inputs in necessary. Therefore, this study focused on assessing the effect of farm inputs and smallholder farmer’s characteristics on irish potato production technical efficiency in Molo Sub County, Nakuru County, Kenya. Cross-sectional data on the 2018/2019 production season was collected using multistage sampling technique from a sample of 360 irish potato farmers. Respondents in the study area were sampled using purposive and random sampling methods. The study employed a questionnaire to collect the relevant data. Descriptive statistics were used to describe the socio-demographic and institutional attributes of the smallholder irish potato farmers. Effect of farm inputs was modelled under the Cobb-Douglas function form under stochastic frontier analysis approach. The model parameters estimated using the maximum likelihood method indicated that land allocated to irish potato production (0.262), seeds (0.629), fertilizer (-0.299) and fungicide (0.131) were significant inputs in irish potato production at 5% level of significance. The level of irish potato production technical efficiency amongst the smallholder farmers was varied. The relative deviation of irish potato production from the maximum possible production level due to technical inefficiency was determined by the discrepancy ratio which was estimated to be 94%. The respondents’ estimated mean technical efficiency was 71%, which implies there is an opportunity of increasing irish potato production by 29% through efficient use of the available farm inputs. Education, gender, access to extension services and farmer group significantly affected the smallholder irish potato production technical efficiency. The negative coefficients on the education, gender, access to extension and farmer group variables indicated that an increase in any one of them while holding the other factors constant would result in a significant increase in the level of technical efficiency. Therefore, smallholder irish potato farmers were producing below their optimum production level with the available farm inputs. This study encourages smallholder irish potato farmers to increase use of the land, seed and fungicide to boost production. Soil testing is also encouraged to ensure that the fertiliser used replenishes the soil nutrients for irish potato production. In order to boost irish potato production, farmers are motivated to increase their literacy levels, form or join existing groups. Access to extension services can also be urged to improve irish potato production levels.
Effect of Teenage Pregnancy on Psychosocial Wellbeing of Expectant Teenage Girls And Their Coping Mechanisms Among Girls in Trans Nzoia West Sub-County, Kenya
(Chuka University, 2019-09) Njuki, Naomi Gatwiri
Teenage pregnancy refers to the situation where young girls ranging from thirteen to nineteen years of age become pregnant. During their pregnancy the teenage girls are affected in their psychosocial lives. The expectant teenage girls also tend to employ coping mechanisms which can be positive or negative. Psychosocial wellbeing is the positive affective state such as personal growth, positive relations and self-acceptance and interpersonal relations of the expectant teenage girls. The cases of teenage pregnancy have been on the rise. In Trans Nzoia County the teenage pregnancy rate is 18 percent. Expectant teenage girls have been reported to procure abortions which have led to death and other health problems among expectant teenage girls. Societal coping mechanisms are essential for the expectant teenage girls to cope with pregnancy. Therefore, the purpose of this study was to establish the effect of teenage pregnancy on psychosocial wellbeing of expectant teenage girls and their coping mechanisms among girls in Trans Nzoia West Sub County. The study applied two theories which are Crisis theory by Caplan and Problem Behaviour Theory by Jessor. The study used the descriptive survey research design. This design was considered appropriate for the study because it is useful in securing evidence concerning an existing situation or current condition. The target population for this study was 136 expectant teenage girls in Trans Nzoia West Sub County. The sample size was 103 expectant teenage girls who were sampled using purposive sampling technique. A pilot study was carried out to test for the reliability of the instruments. The validity of the instruments was ascertained through expert judgment from Chuka University Department of Education and other experts. A pilot study was carried out to test for the reliability of the instruments. The reliability co-efficient of the tools was tested using split half technique and Spearman rho correlation coefficient. The obtained reliability co- efficient of the instruments was 0.83. Data was collected by use of Focus Group Discussion and Questionnaires which were administered to the expectant teenage girls and interviews were conducted among the nineteen nurses. The data collected was organized, coded, tabulated and analyzed using Statistical Package for Social Sciences (SPSS) version 20. The findings showed that expectant teenage girls were experiencing low self-esteem, poor interpersonal relationship and depressive symptoms. The expectant teenage girls reported that they felt unfortunate because of the pregnancy. They were also very critical of themselves and do not like interacting with others. Participants gave reports that teenage pregnancy was seen as a shameful event for the teenagers involved. This led to poor interpersonal relationship with their partners and relatives. The study showed aspect of depressive symptoms whereby expectant teenagers reacted to the realization of pregnancy with anxiety, hopelessness and thoughts of taking away their lives. The study also found out that the expectant teenagers were using coping mechanisms such as religion, social support and counseling. These coping mechanisms have made the expectant teenagers cope with their pregnancy better. The findings and recommendations of this study may provide information to expectant teenage girls concerning coping mechanisms that can be used to cope with teenage pregnancy better. The information may help the Ministry of education to be aware of the necessary factors to take into consideration when formulating and implementing policies and programmes designed to sensitize teenagers about the effect of teenage pregnancy and coping mechanisms of teenagers who are pregnant.
Assessment of The Distribution, Abundance and Carbon Stocks in Seagrass Meadows Within Eastern and Western Creeks of Gazi Bay, Kenya
(Chuka University, 2019-09) Juma, Gabriel Akoko
Seagrass meadows are one of the most important blue carbon ecosystems within the seascape environment providing both ecological and economic benefits. They act as breeding and feeding grounds for fish and other organisms; perform carbon sequestration, nutrient cycling and other ecosystem services. Through their carbon capture and storage ability, seagrass can be incorporated in carbon offset schemes. However, they are highly degraded from both anthropogenic and natural factors. Carbon stocks assessment is required in understanding dynamics of seagrass meadows. In Gazi Bay, Kenya, carbon storage in the seagrass meadows has been determined in the open waters of the Bay. The present study aimed at contributing to carbon dynamics of Gazi bay by assessing the distribution, abundance and carbon storage in seagrass within the mangrove fringed creeks. The objectives included assessing distribution and abundance of seagrass in the creeks, determining above and below ground seagrass biomass and comparing sediment carbon stocks between vegetated and un-vegetated sites. Stratified random sampling strategy was used in collecting data within 80 square plots of 0.25m by 0.25m. Five species formation viz; Thalassia hemprichii, Cymodocea rotundata, Cymodocea serrulata, Enhalus acoroides, and Thalassidendron ciliatum were encountered as either single or mixed stand. A total of 480 samples were collected for sediment and biomass determination in the laboratory. The results showed a higher seagrass diversity in the Eastern creek, (H = 1.71), than Western creek, (H = 1.67). There was also a significant difference in the total biomass between the creeks (t= -8.44, df. = 53, p < 0.0001) and among species (F = 14.6, df = 79, p < 0.0001) with a mean of 7.25 ± 4.2 Mg C ha-1, (range: 4.1 - 12.9 Mg C ha-1). Sediment carbon varied between species within the 1.2 km2 creeks area; with a range from 97.6 to 302.4 Mg C ha-1, (mean: 183.4 ± 100.5 Mg C ha-1). This is lower than 236 ± 24 Mg C ha-1, reported in the open bay but within the global range. In all the species, vegetated areas showed significantly higher carbon values than the un-vegetated sites (t = 12.02 p < 0.0001). Based on this study, the total seagrass carbon stocks can be estimated at 21,118.8 Mg C. Using the IPCCC emission value of 7.9 tonnes of C ha-1, values for organic soils for wetlands, conservation of seagrass in these two mangrove fringed creeks will prevent emission of 2,682.13 Mg of CO2 equivalent yr-1 to the atmosphere. The avoided emission could be bundled with the existing offset scheme in the bay involving mangroves. Inclusion of seagrass in carbon offset scheme has a long term benefits of climate, community livelihood and biodiversity conservation.

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