Flower and pod genes involved in soybean sensitivity to drought

In soybean, studies on drought-responses are conducted during vegetative season. Information related to genes triggered in response to water-deficit (WD) in flower and pod is lacking. We performed an RNASeq and an agro-physiological characterization at stages R2 and R4 of soybean cultivar BR16, under WD. Physiological results showed a decrease in gas exchange parameters. Agronomical results showed WD impaired yield. Global Gene Ontology analyses indicated that most of the Differential Expressed Genes (DEGs) were down-regulated in flowers but up-regulated in pods. qRT-PCR revealed that WD triggered hormone biosynthesis changes. Mechanisms such as a decrease in glyceollin levels and cell wall instability were observed. This data showed tissue-specific mechanisms correlated with phenotypic responses such as drought escape, early flowering hormone-induced, and loss in grain weight. We presented here a comprehensive expression profile of flowers and pods soybean genes, which could guide researchers in the development of plants more tolerant to drought.