Proteomic analysis of seed germination under salt stress in soybeans

Abstract

Soybean (Glycine max (L.) Merrill) is a salt-sensitive crop, and its production is severely affected by saline soils. Therefore, the response of soybean seeds to salt stress during germination was investigated at both physiological and proteomic levels. The salt-tolerant cultivar Lee68 and salt-sensitive cultivar N2899 were exposed to 100 mmol/L NaCl until radicle protrusion from the seed coat. In both cultivars, the final germination percentage was not affected by salt, but the mean germination times of Lee68 and N2899 were delayed by 0.3 and 1.0 d, respectively, compared with controls. In response to salt stress, the abscisic acid content increased, and gibberellic acid (GA 1+3 ) and isopentenyladenosine decreased. Indole-3-acetic acid increased in Lee68, but remained unchanged in N2899. The proteins extracted from germinated seeds were separated using two-dimensional gel electrophoresis (2-DE), followed by Coomassie brilliant blue G-250 staining. About 350 protein spots from 2-DE gels of pH range 3 to 10 and 650 spots from gels of pH range 4 to 7 were reproducibly resolved, of which 18 protein spots showed changes in abundance as a result of salt stress in both cultivars. After matrix-assisted laser desorption ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) analysis of the differentially expressed proteins, the peptide mass fingerprint was searched against the soybean UniGene database and nine proteins were successfully identified. Ferritin and 20S proteasome subunit β-6 were up-regulated in both cultivars. Glyceraldehyde 3-phosphate dehydrogenase, glutathione S-transferase (GST) 9, GST 10, and seed maturation protein PM36 were down-regulated in Lee68 by salt, but still remained at a certain level. However, these proteins were present in lower levels in control N2899 and were up-regulated under salt stress. The results indicate that these proteins might have important roles in defense mechanisms against salt stress during soybean seed germination.

Effect of manure, Phosphate Solubilizing Bacteria, and chemical fertilizer application on the growth and yield of soybean

“…Detam-3, Seulawah, Merbabu, Gumitir, Ichiyou, and Petek delayed germination but did not reach one day. Xu et al (2011) reported that 100 mMolal.L -1 NaCl decreases MGT value. Farhoudi and Tafti (2011) and Taufiq and Purwaningrahayu MGT is average time of germination.…”

“…In soybean, salinity is known to delay germination time (Xu et al 2011;Taufiq and Purwaningrahayu 2013;Kandil et al 2015). Soybean germination percentage decreases significantly with increasing levels of saline.…”

Enhancing Antioxidant Properties of Germinated Thai rice (Oryza sativa L.) cv. Kum Doi Saket with Salinity

“…Seed germination is a complex process involving biochemical and physical activities [1,40]. Hydrolytic enzymes are activated after the imbibition of water and decompose large molecular substances of reserve compounds such as starch, non-starch polysaccharides, and proteins in the endosperm, leading to increases in small molecular compounds such as glucose, oligosaccharides and amino acids in germinated seeds [1,2,41].…”

“…Besides ionic and osmotic effects, which are the primary stresses of salinity, high salt concentrations additionally induce secondary stresses such as oxidative stress due to the excessive generation of ROS [40,42,43]. To prevent oxidative damage, plants process both enzymatic mechanisms such as APX and CAT, and non-enzymatic mechanisms such as phenolic compounds for ROS scavenging [7,8,43].…”

Response of Different Soybean (Glycine Max L.) Genotypes Grown in Sand Culture to Salinity Stress

“…Over 20 50% of the whole arable land is affected by salt stress every year (Xu et al, 2011). Salinity decreases the productivity of most crops as plant growth is affected in several aspects of its metabolism.…”