Abstract

Crop yields in arid lands are generally low and highly variable because of sparse and erratic precipitation leading to water stress. A greenhouse study was conducted to determine the effect of integrated nutrient management and mulching on the yield, nutrient uptake and water use efficiency (WUE) of sorghum. The treatments compared were: control, full N + P fertilizer, compost, manure, ½ N + P fertilizer + compost, and ½ N + P fertilizer + manure. Straw mulch was applied at the rate of 28 g pot^-1 to one set of this experiment, while the other set did not receive straw mulch. Mulching gave statistically superior results over no mulch with respect to grain and stover yields, total N and P uptake, and water use efficiency (WUE), and it also reduced total water used. Among the nutrient management treatments, full N + P fertilizer gave the best results, however, it differed non significantly for ½ N + P fertilizer + compost and ½ N + P fertilizer + manure treatments for grain yield, total N and P uptake, and WUE. Difference between compost and manure applied either alone or with ½ N + P fertilizer was non-significant to all the crop parameters mentioned before. It was concluded that when mulch water was used more efficiently, it produces higher crop yield as compared to no-mulch. Similarly, combined use of organic and mineral fertilizers reduced the amount of water used by the crop; still the crop yield and WUE were comparable with NP fertilizer.

Key words: Integrated nutrient management, mulching, NP fertilizers, sorghum yield, WUE.