Impact of deficit irrigation on sweet pepper (Capsicum annuum var. Simbard) performance: Assessing growth, yield, and water use efficiency under a four-day interval irrigation

This study investigated the effects of a four-day irrigation interval at varying levels (100%, 90%, 80%, and 70% of crop evapotranspiration, ETc) on the growth, yield, and water use efficiency (WUE) of sweet pepper in Coastal Savannah zone of Ghana. The study employed a randomized complete block design (RCBD) involving four treatments and three replications to assess plant height, leaf area, fruit number, fruit weight, and WUE across two growing seasons. The findings indicated that 100% ETc produced the greatest growth and productivity, achieving a WUE of 1.3 kg/m³. 90% ETc sustained elevated yields and WUE, indicating that little water stress can improve water utilization without significant yield reductions. Conversely, 70% ETc markedly decreased growth, yield and WUE, highlighting sweet pepper’s vulnerability to water stress, particularly during flowering and fruit maturation. Seasonal variations influenced performance, yielding superior outcomes in the initial season owing to advantageous climatic conditions. The research highlights the significance of stage-specific irrigation, especially during the mid-season when water requirements are at their highest. It advocates for 90% ETc to provide sustainable sweet pepper cultivation in arid places, optimizing water conservation and yield, hence providing essential recommendations for farmers and policymakers on effective water management.