Polyamines, affected the nitrogen partitioning, protein accumulation and amino acid composition of mung bean under water stress

Abstract

Field experiments were conducted in two growing seasons as a split plot based on a randomized complete block design with four replications. Irrigation intervals (irrigation after 70 and 170 mm evaporation from class A pan) were assigned to main plots and spraying of polyamines (putrescine 0.1 mM, spermidine 0.1 mM, and spermine 0.1 mM) were allocated to the subplots. T nitrogen and sulfur content of different parts of mung bean, nitrogen uptake, protein filling duration, protein percentage of grain, maximum protein content per grains, grain and protein yields per unit area, methionine and serine contents reduced under water limitation, but grain filling rate, isoleucine, leucine, threonine, aspartic acid, glutamic acid, glycine, proline, tyrosine and arginine contents in grains raised. Treatment of plants with polyamines improved the contents of nitrogen and sulfur, nitrogen uptake, protein-filling duration, protein percentage, grain and protein yield per unit area, and histidine, methionine, phenylalanine, threonine, aspartic acid, glutamic acid, tyrosine, and arginine contents in grain. Putrescine had the highest grain and protein yields. Our results clearly indicated that polyamines with improving histidine, methionine, phenylalanine, and threonine content in mung bean grains improved the quality of mung bean protein.