Evaluation of above ground biomass production of maize at different levels of irrigation

Abstract

Improper water allocation is still a challenge of irrigated agriculture. Excess or little application of water affects crop yields which in turn affect crop productivity. This study was conducted to evaluate the effect of different irrigation levels on biomass under drip irrigated maize at Makerere University Agricultural Research Institute Kabanyolo. The irrigation levels were four each replicated three times and these were 100% Fully Irrigated Treatment (FIT), 75% of FIT, 50% of FIT and 0% of FIT which was the rainfed treatment. Irrigation was scheduled for 10-day interval and the field was laid in a Completely Randomized Block Design. Required climatic data was obtained from the NASA Agroclimatology website and was used to calculate Eto using the Eto calculator software version 3.2 which was then used to obtain the crop water requirement. Representative plants were harvested at the ground level from each plot on a biweekly basis, oven dried at 65°C for 48 hours and then weighed using an electronic scale of (±0.0001g). The measured data was then subjected to Analysis of Variance by one-way (ANOVA) with Turkey’s multiple comparison test using SPSS version 23 software. Results showed that the irrigation levels significantly affected dry Above Ground Biomass at P<0.05 significance level. The highest and lowest dry Above Ground Biomass were 54.725 and 18.529 g/cm2, 70 days after sowing for Fully Irrigated and rainfed treatments respectively. There is need for irrigated agriculture/ supplementary irrigation so as to improve on plant performance and hence the yields since the Above Ground Biomass can be used to estimate yields. Proper timing and application of water in the right quantities greatly improves on plant performance.