Effect of Water Stress Imposed at Different Growth Stages on Growth and Yield of Two Varieties of Capsicum annum L.

Abstract

Water availability is an important factor in determining yield of Capsicum. The response to water stress in capsicum could vary on the growth stage. Therefore, the objective of this study was to determine the effects of water stress imposed at vegetative and reproductive stages on the growth and yield of two selected capsicum varieties (HYW and CA8). Plants were grown in pots in a rain sheltered plant house in zone IL1a . Water stressed (S) and well watered (W) conditions were imposed at vegetative and reproductive stages as: WW-well watered in both vegetative (V) and reproductive (R) stages; WS-well watered in V and water stressed in R; SWwater stressed in V and well watered in R and SS-water stressed in both V and R. At 50% flowering, plant water potential, fresh and dry weights and leaf area per plant were significantly greater in WW and WS than in SW and SS. At the reproductive stage (50% flowering), water potential was significantly greater WW and SW than in WS and SS. Fresh and dry weights and leaf area per plant showed a decreasing trend for WW, WS, SW, SS respectively in both varieties. Greatest yield reductions were observed in SS, with 66% and 95% in HYW and CA-8 respectively. In both varieties, water stress at the reproductive stage caused a greater yield loss than at the vegetative stage. Therefore, pod numbers and weight per pod decreased. However, no advantage of greater rooting ability on yield under water-limited conditions.