COLCHICINE-INDUCED MUTAGENESIS ON GROWTH AND YIELD CHARACTERS OF A COWPEA VARIETY

The induced mutation techniques have been used successfully in various crops, but their application in cowpea breeding is limited. This research evaluates the effects of colchicine treatment on the growth and yield attributes of the cowpea variety 'Bewehe'. The objective was to assess the mutagenic influence of colchicine on the growth and yield characteristics of cowpea, examining various concentrations (0.00%, 0.05%, 0.10%, and 0.15%) and exposure durations (0, 2, 4, and 6 hours) within the M1 generation. The experiment was a four x four factorial arrangement within a completely randomized design, incorporating three replications. The colchicine treatment had a significant effect (p<0.05) on most growth and yield parameters assessed, except the number of main branches and the length of terminal leaves. The most favourable growth conditions were at a concentration of 0.05% for 2 hours. The highest yield was at a concentration of 0.15% for 6 hours. Colchicine treatment notably enhanced seed weight, with peak values achieved at the 6- hour treatment duration and 0.15% concentration. There were significant positive correlations between survival percentage and germination percentage, between the number of leaves and days to first flowering, between 100 seed weight and the number of leaves, and between 100 seed weight and germination percentage. The colchicine treatment improved seed weight and established strong positive correlations among growth and yield traits. Early flowering positively correlated with lower germination, shorter plant height, and reduced survival. Colchicine treatment in cowpeas results in complex interactions between vegetative and reproductive traits, highlighting the need for optimal treatment conditions to balance growth and yield outcomes.