Interactive effects of irrigation rate and leaf harvest intensity on edible leaf and fruit yields of multipurpose pumpkin (Cucurbita moschata Duchesne).

Abstract

Pumpkin (Cucurbita moschata Duchsene) is rapidly gaining popularity in dishes in Kenya. The fruits, leaves and seeds are becoming popular due to their nutritional and medicinal properties. However, water stress and irregular leaf harvesting constrain optimal yields. The present study determined effects of irrigation rate and leaf harvest intensity in sustaining enhanced growth and quality. A split-block embedded in Randomized Complete Block Design with four replications was set up in a rain shelter that blocked rain from plots. Irrigation was applied to main plots and leaf harvest intensity to split-blocks. The treatments were 1, 2, 3 and 4 litres applied once per week through drip tubes and 0, 1, 2 and 3 leaves harvested once per fortnight per branch. One plant spaced at 2mx2m and replicated four times formed a treatment. The variables measured were: leaf and fruit growth; male and female flowers; fruit quality; seed number, weight, germination and vigour. Data were subjected to analysis of variance using JMPIN 5.1 software. Tukey’s Studentized Range Test at P=0.05 was used to separate means. Leaf harvest intensity had a significant P<0.05 was used to separate means. Leaf harvest intensity had a significant (P 0.05) decreasing effect on flower, leaf and fruit growth and quality. Irrigation rate had a significant (P 0.05) increasing effect on branches, flowers and seedling vigour. Interaction had a significant (P 0.05) increasing effect on leaves, seeds and male flowers. Irrigating with 3 L sustained the best performance and hence is recommended. Harvesting two leaves is recommended for producing many edible leaves, and one or no leaf for high quality fruits and seeds.