Growth and yield analysis of ‘Robusta’ banana in relation to soil water potential and nitrogen fertilization

Abstract

‘Robusta’ banana was subjected to 4 soil water potentials (−25, −45, −65 and −85 kPa SWP) under 3 levels of N fertilization (100, 200 and 300 g plant −1). Most frequent irrigation when the SWP reached −25 kPa resulted in maximum dry-matter production, leaf area index (LAI), leaf area duration (LAD) and crop growth rate (CGR), producing the highest fruit yield (52.8 t ha −1) although it was not significantly different from less frequent irrigation at −45 kPa (51.8 t ha −1). Irrigation at SWP of −65 and −85 kPa had significant adverse effects on growth and productivity as compared to frequent irrigation. Increasing N application from 100 to 200 g plant −1 significantly increased the fruit yield (from 45.3 to 49.3 t ha −1), this improvement being due to significant increases in LAI, LAD and CGR leading to higher dry-matter production. Net assimilation rate (NAR) and relative growth rate (RGR) remained largely unaffected by SWP and N fertilization.