The Effects of Plant Population and Harvesting Interval on the Growth and Yield of Slender Leaf (Crotalaria Brevidens)

Abstract

Slenderleaf (Crotalaria brevidens), is a species of Crotalaria that is used as a vegetable in Kenya. It is a highly nutritive leafy vegetable, a sources of provitamin A, Vitamin C, carotenoids, iron protein and calcium. Production of slender leaf in Kenya is low at 3 tons per hectare compared to a research potential of 10 tons per hectare. Though extensive research has been done to evaluate the effect of nitrogen and phosphorus on the growth of slender leaf; no work has been carried out in Kenya on the effect of plant population and fresh leaf harvesting interval on the yields of slender leaf. An experimental study was carried out at Kisii Farmers Training Centre in Kisii County, Kenya, to determine plant population and harvesting interval effects on the fresh leaf yield and grain seed yield of the slenderleaf (Crotalaria brevidens). A Randomized complete block design with factorial arrangement of three levels of plant population 30 cm x 30 cm, 30 cm x 20 cm and 30 cm x 15 cm and four levels of leaf harvesting intervals 7days, 28days, 49 days and at maturity) treatments were used to evaluate the growth and yield potential of slenderleaf. Data collected was analyzed using SPSS 21.0. Analysis of variance was done to identify significant means between treatments and Least Significant Difference was used to separate the means at P=0.05. Results indicated that fresh leaf yield is depended upon the harvesting interval (intensity) and plant population (p<0.05). Wider spacing (low plant population) and less frequent leaf harvesting (defoliation) resulted in low fresh and dry leaf weight yields. Harvesting interval was significant and had a greater effect on fresh leaf yield (p<0.05) as opposed to plant population (p= 0.985). Plant population had a great significant on plant growth (stem height and number of branches). The effect of harvesting interval and plant population was significant in pod formation and seed weight as observed from all the treatment combinations with 30 cm x 30 cm and at maturity harvesting interval giving the highest number of pods. The dry grain weight was greatly influenced by both plant population and harvestings interval with 30 cm x 20 cm and at maturity, giving the highest seed yields of 3,500kg/Ha. The results of the study indicated that fresh leaf yield of slenderleaf can be greatly increased by using a harvesting interval of 28 days and 30 cm x 20 cm plant spacing.