Biochemical changes and SDS-PAGE analyses of chickpea (cicer arietinum L.) genotypes in response to salinity during the early stages of seedling growth

Salinity is one of the most serious abiotic stresses for plants, causing other subsequent consequences such as oxidative stress, which eventually leads to cell death. Measured various biochemical parameters in chickpea genotypes were performed under various NaCl concentrations (0, 8 and 12 dS.m-1 ( in controlled condition at 21 and 28-day after sowing (DAS). After determination of tolerant (MCC544) and susceptible (MCC806) genotypes and also the best differential salt concentration, SDS-PAGE was used to compare protein profiling in these two genotypes in 3 time points with four replicates. Proline and protein contents were significantly higher in MCC544 as much as 27 fold (for proline) and 30% (for protein) increase over control in 28 DAS at 12 dS.m-1 of salt. The leaf soluble carbohydrates increased significantly in MCC544 and MCC760, compared with others. The minimum decline of electrolyte leakages (6%) and malondialdehyde (MDA) content was belonged to MCC760 while MCC806 genotype showed the highest decrease rate (more than 20%). Total leaf chlorophyll content decreased in all genotypes. More strong and positive correlations between parameters was recorded in tolerant genotypes which resulted in membrane and osmotic balance. Analyses of SDS-PAGE revealed that more rapid accumulation and/or less degradation of proteins occurred in higher molecular weight proteins. Moreover, the response of genotypes through protein changes before 96 h stress might be a possible reason for salinity tolerance in this condition

Linnaeus on Pearls

Protein expression patterns in imbibed seeds of three cultivars of chickpea (<i>Cicer arietinum</i> L.) with different rates of germination under limiting water supply in soil (>10% water holding capacity) were compared. A large number of soluble proteins expressed earlier and at higher levels in <i>cv</i> Rupali seeds compared to two other genotypes that germinated less rapidly (KH850) or not at all (KJ850). Among the proteins identified were those with chaperone-like functions, including LEA and HSP proteins and proteins involved in metabolism of reactive oxygen species (ROS). Only NAD-malate dehydrogenase was identified as an early, differentially abundant enzyme of the TCA cycle, but in <i>cv</i> Rupali, expression of phospho-enol-pyruvate carboxykinase rose very rapidly to a high level, indicating that an anaplerotic C input to the TCA cycle may have been important. Proteinase inhibitors were more highly expressed in the genotype that did not germinate compared to <i>cv</i> Rupali. Clustering analysis of proteomic data indicated a link between groups of proteins, implying a common regulatory mechanism possibly at the transcriptional level. The chaperone-like proteins and enzymes of ROS homeostasis provide a useful starting point for molecular genetic analysis that may well identify other important genes for the early germination trait