Assessment of Drought Stress Effects on Maize Productivity in Sokoto State

This study assesses the effects of drought stress at different growth stages on the growth parameters and grain yield of maize in Sokoto State, North West Nigeria. Maize is an increasingly important food and feed crop in northern Nigeria, but its production in semi-arid zones is highly vulnerable to drought stress, particularly during the critical vegetative-reproductive transition, flowering, and grain-filling stages. Understanding which growth stages carry the highest drought sensitivity is critical for selecting stress-tolerant varieties and optimising management practices. This study establishes a pot-based controlled experiment at Usmanu Danfodiyo University Sokoto, imposing drought stress by withholding irrigation during three growth windows: vegetative (V4-V8), flowering and silking (VT-R1), and grain fill (R2-R4), alongside a fully irrigated control. SAMMAZ 50 drought-tolerant variety is used. Leaf water potential, stomatal conductance, chlorophyll content, anthesis-silking interval, number of kernels per ear, kernel weight, and grain yield are measured. Findings reveal that drought stress during flowering and silking produces the most severe yield reduction of 68 percent below the well-watered control, primarily through extended anthesis-silking interval and reduced kernel set. Vegetative stage stress reduces yield by 32 percent, while grain fill stress reduces yield by 48 percent. The study concludes that the flowering and early grain fill period is the most critical drought-sensitive window for maize production in Sokoto State conditions, and recommends supplemental irrigation targeting this period if water is available.

Keywords: drought stress, maize yield, growth stages, Sokoto State, anthesis-silking interval.