Critical stages of wheat (Triticum aestivum) for irrigation under different water availability conditions in Vertisols of Central India

Abstract

The field experiment was conducted during winter (rabi) seasons of 2015–16 and 2016–17 at ICAR-Indian Agricultural Research Institute, Regional Station, Indore, Madhya Pradesh, to identify most critical stages of wheat (Triticum aestivum L.) under varying availability of irrigation water for higher and economic wheat production in Vertisols of Central India. Total 15 treatments consisting of the control and different critical stages for irrigation, viz. crown-root initiation (CRI), late tillering, late jointing, late flowering and late milking, and their combinations were selected for irrigation. Results indicated that 4 irrigations applied at CRI + tillering + late jointing + late flowering stages resulted in the maximum plant height (93.3 cm), spike length (10.47 cm), spikelets/spike (17.4), 1,000-grain weight (45.4 g), grain yield (5.32 t/ha), soil plant analysis development (SPAD) value (54.4), normalized difference vegetation index (NDVI) value (0.76), energy output (184,704 MJ/ha), net returns (`66,385/ha) and benefit : cost ratio (2.59). Above values including biological yield (13.86 t/ha) and sodium dodecyl sulfate (SDS) value (40.4 ml) were almost similar with 5 irrigations applied at all critical stages, but substantially higher over rest of the treatments. In case of lower levels of irrigations, 3 irrigations applied at CRI + late tillering + flowering; 2 irrigations applied at tillering + flowering and 1 irrigation at late tillering stage recorded higher, energy efficient and economical wheat productivity than with their similar level of irrigation at the other stages. Water-use efficiency, canopy temperature, energy-use efficiency and energy productivity were decreased with the increase in the levels of irrigation. Hence, for getting higher, energy-efficient and economic wheat grain production, 4 irrigations can be applied at CRI + tillering + late jointing + flowering stages. In case of availability of only 3 irrigations, crop should be irrigated at CRI + tillering + flowering stages, 2 irrigations at tillering + flowering and single irrigation at tillering stage in Vertisols of Central India.