EFFECT OF DROUGHT AT DIFFERENT REPRODUCTIVE STAGES ON YIELD AND YIELD COMPONENTS OF SOME COWPEA (VIGNA UNGUICULATA L. WALP) VARIETIES IN LAPAI, NIGER STATE, NIGERIA

Abstract

Drought is one of the most   unfavorable  abiotic factors  that  can  affect  the growth  and yield of  cowpea. Drought at different  reproductive stages can interfere with the morphological  processes of  plants. Therefore this   research aim to  determine   the effect of drought at different reproductive  stages on yield and yield components of some cowpea varieties. A screen house experiment was conducted at the Botanical Garden of Biological Science Department, Ibrahim  Badamasi  Babangida, University during the 2022 cropping season  The three cowpea varieties used were; FUAMPEA 1, FUAMPEA 2 and ITK89KD-288 which were planted and subjected to water stress at three different reproductive stages which included; early flowering stage, early pod set stage, early seed filling stage and a well-watered treatment to serve as control. The treatments were arranged in a Complete Randomized Design (CRD) in three replications. Cowpea yield attributes evaluated were; number of pods per plant, pod length, pod weight per pot, number of seeds per pod, 100 seed weight, total grain yield per pot and estimated grain yield per hectare. Results revealed   that variety was highly significant (p≤0.01) for pod length, total grain yield per pot and estimated grain yield per hectare. On the other hand, drought was significant (p≤0.05) for pod weight per pot. Variety however was not significant for number of pods per plant, number of seeds per pod and 100 seed weight. Drought showed a highly significant effect (p≤0.01) on number of pods per plant, pod length, pod weight per pot, number of seeds per pod, 100 seed weight, total grain yield per pot and estimated grain yield per hectare. Water stress at early seed filling stage significantly reduced total grain yield per plot and total grain yield per hectare. Drought at different reproductive stages affects  the morphological and physiological processes of cowpea as a crop. This is an indication that water is very crucial during the  growth and yield  of cowpea.