The Effects of Deficit Irrigation, Deficit Irrigation–Chicken Manure, and Deficit Irrigation–NPK 15:15:15 Interactions on the Growth and Yield of Okra (Abelmoschus esculentus) in Pot and Field Experiments

Abstract

The research was conducted at University of Cape Coast Research Farm, Cape Coast, Ghana, from February 2014 to February 2015. The objective of the research was to investigate the effects of deficit irrigation, deficit irrigation chicken manure combination and deficit irrigation-NPK 15:15:15 combination on the growth and yield of Okra in pot and field experiments. The Randomized Complete Block Design was used for the pot experiment with nine (9) treatments replicated three (3) times. The 9 treatments were 100% (T1) crop water requirement (CWR), 90% CWR (T2), 80%CWR (T3), 100%CWR + 5t/ha chicken manure (T4), 100%CWR + 10t/ha chicken manure (T5), 90%CWR + 5t/ha chicken manure (T6), 90%CWR + 10t/ha chicken manure (T7), 80%CWR + 5t/ha chicken manure (T8), and 80%CWR + 10t/ha chicken manure (T9). It was observed in the pot experiment that T7 had a comparable yield with 100% CWR + chicken manure and 80% deficit irrigation + chicken manure performed poorly. In the field experiment, T1-T9 was maintained but six (6) NPK treatments were added to bring the total to 15. The 6 NPK treatments added were 100%CWR + 200kg/ha NPK (T10), 100%CWR + 250kg/ha NPK (T11), 90%CWR + 200kg/ha NPK (T12), 90%CWR + 250kg/ha (T13), 80%CWR + 200kg/ha NPK (T14) and 80%CWR + 250kg/ha NPK (T15). Deficit and full irrigation-chicken manure performed better than deficit and full irrigation-NPK at 100%CWR and 90%CWR. Twenty percent deficit irrigation plus high doses of chicken manure and NPK performed poorly. Ten percent deficit irrigation with 10t/ha chicken manure and 250kg/ha NPK are best for okra production.