Effects of low light intensity on radiation use efficiency and productivity of tropical pulses

Abstract

Pulses have distinct morpho-physiological response under reduced sunlight. But little is known for their capacity to adapt to the level of shading encountered in crop mixtures. Field experiment was conducted to evaluate the pulses under artificial shade during rainy season at Raichur, Karnataka. Objectives were to select potential pulse crop tolerant to shade based on productivity and radiation use efficiency (RUE). Experiment was laid out in split-plot design, wherein light intensity (unshade, 50 and 75% shade) in main plots and pigeon-pea, cowpea, lablab and black-gram were in sub plots. Shade levels were created by the erection of white shade nets at 25 DAS continued upto harvest. Results indicated that irrespective of the crop more pods, grain, stover and protein yield were recorded under unshade. While, pigeon-pea and lablab were produced significantly higher yield under unshade, however, these were also well performed under 50 per cent shade over black-gram and cowpea. However, seeds crude protein was higher in shaded plants compared to unshaded. Significantly higher RUE (2.22 gMJ-1) was recorded in pigeon-pea under 75 per cent shade and lowest in unshaded lablab (0.35 gMJ-1) and black-gram (0.40 g MJ-1). Results inferred that pigeon-pea and lablab were found tolerant to shade compared to cowpea and black-gram and may be suitable for crop mixtures cultivation.

Keywords

• Grain yield,
• pulses,
• radiation use efficiency
• shade tolerance
• sunlight