Contrasting responses to waterlogging in emergence, growth, and yield of mungbean and blackgram

Background and aims

Pulses- grain legumes are vulnerable to waterlogging (WL) in South Asia. This study examined the effects of WL on two pulses at germination and reproductive stages and tested hypotheses: Mungbean (Vigna radiata L.) and blackgram (Vigna mungo L.) differ in WL tolerance; and the differences are due to phenotypic and growth traits.

Methods

Three mungbean and one blackgram cultivar were grown in pot-soil system. The treatments were at germination stage, 0 (drained control), 3, 5 and 7 d WL, while at the reproductive stage 0 (drained control), 3, 6 and 9 d WL and then drained to allow recovery (RE).

Results

Seed emergence decreased with longer WL duration. Blackgram cultivar showed 38% emergence, while mungbean cultivars had 14–18% after 7 d of WL. At the reproductive stage, WL reduced shoot and root growth compared to drained control. After 30 d of recovery, the chlorophyll concentration of first trifoliate leaves increased by 15% in blackgram cultivar, while it decreased in mungbean cultivars compared to their drained controls. Blackgram had higher relative growth rate (RGR) than mungbean at 9 d WL. After 9 d of WL, blackgram seed yield was reduced by 40% and mungbean cultivars by 52–60% compared to drained controls.

Conclusions

This study has provided evidence of a difference in WL tolerance between two summer pulses at both stages for the particular soil used here. Seedling emergence, RGR and yield attributed the variation. These new findings will allow growers to select suitable crops for different cropping systems.