Genetic diversity and proteomic analysis of vegetable soybean (Glycine max (L.) Merrill) accessions grown in mineral and BRIS soils

Knowledge of the molecular mechanisms of response to environmental stress is fundamental for the development of genetically stress-tolerant crops. This study aims to find vegetable soybean accessions tolerant to cultivation in stressful tropical environments. Fourteen accessions of the vegetable soybean (Glycine max (L.) Merrill) were grown in mineral and beach ridges interspersed with swale (BRIS) soils. The genetic diversity, estimated using inter-simple sequence repeat (ISSR) markers, revealed 42.50% polymorphism and was regarded as moderate. The unweighted pair-group method arithmetic average (UPGMA) analysis allocated the tested accessions into five major clusters at a similarity coefficient level of 0.43. The lowest values of the genetic distance were between IIUMSOY11 and IIUMSOY13 & IIUMSOY13 and IIUMSOY14, indicating that these accessions were more genetically distant from the other accessions. Ten differentially expressed proteins were identified in the three selected accessions IIUMSOY1, IIUMSOY11 and IIUMSOY14 using mass spectrometry, revealing a unique expression of the proteins involved in the storage, flavonoid metabolism, protein modification, oxidative stress defence, carbohydrate metabolism and respiratory chain. The findings may be valuable for the selection of genetically diverse accessions, to enhance the breeding of vegetable soybean genotypes suitable for stressful tropical environments.