Quantification of Radiation Use Efficiency and Yield of Wheat as Influenced by Different Levels of Nitrogen and Water Stress under Semi-Arid Conditions of Faisalabad

Abstract

Crop production is greatly influenced by water and nutrition stress in semi-arid areas. Nitrogen and water are two most important yield limiting factors which effect economic production of wheat. Drought initiates when large area of land suffers from absence of precipitation for temporary periods. Though, not only water scarceness but also low relative humidity and high temperature are other climate factors which induce drought condition. Whereas Effective nutrition (nitrogen) maintains crops metabolic activities and has the potential to lessen drought stress. According to study carried out to explore the influence of varying levels of potential soil moisture deficit (PSMD) and nitrogen, an experiment was planned at agronomy research area, University of Agriculture, Faisalabad. It was laid out in randomized complete block design (RCBD) with split plot arrangement, and replicated thrice. Two factors: potential soil moisture deficit levels (I1: irrigation at 50 mm PSMD, I2: irrigation at 75 mm PSMD and I3: irrigation at 100 mm PSMD) were randomized in main plots, while sub plot nitrogen levels {control (No nitrogen), 50, 100 and 150 kg N ha-1} were randomized. Adequate nitrogen application along with sufficient irrigation management gave highest yield. Under water deficit conditions adequate nitrogen application ameliorates the drought stress. Highest plant height (86.27 cm), number of productive tillers (320.0), grain·spike-1(49.73), test weight (50.55 g) and grain yield (6.72 t·ha-1) were observed with 75 mm PSMD and 150 kg·ha-1 application of nitrogen. While radiation use efficiency for dry matter accumulation of wheat ranged from 1.53 - 1.87 g·MJ-1 whereas, radiation use efficiency for grain yield ranged from 0.421 - 0.473 g·MJ-1. Results revealed that highest RUE obtained I3 (75 mm PSMD) and nitrogen application at 150 kg·ha-1. Judicial application of irrigation and fertilizer not only boosts the yield but also saves resource and increases former output.