Alteration of proteome in germinating seedlings of piegonpea (Cajanus cajan) after salt stress.

Pigeonpea (Cajanus cajan) is an important crop in semi-arid regions and a significant source of dietary proteins in India. The plant is sensitive to salinity stress, which adversely affects its productivity. Based on the dosage-dependent influence of salinity stress on the growth and ion contents in the young seedlings of pigeonpea, a comparative proteome analysis of control and salt stressed (150 mM NaCl) plants was conducted using 7 days-old seedlings. Among various amino acids, serine, aspartate and asparagine were the amino acids that showed increment in the root, whereas serine, aspartate and phenylalanine showed an upward trend in shoots under salt stress. Furthermore, a label-free and gel-free comparative Q-Tof, Liquid Chromatography-Mass spectrometry (LC-MS) revealed total of 118 differentially abundant proteins in roots and shoots with and without salt stress conditions. Proteins related to DNA-binding with one finger (Dof) transcription factor family and glycine betaine (GB) biosynthesis were differentially expressed in the shoot and root of the salinity-stressed seedlings. Exogenous application of choline on GB accumulation under salt stress showed the increase of GB pathway in C. cajan. Gene expression analysis for differentially abundant proteins revealed the higher induction of ethanolamine kinase (CcEthKin), choline-phosphate cytidylyltransferase 1-like (CcChoPh), serine hydroxymethyltransferase (CcSHMT) and Dof protein (CcDof29). The results indicate the importance of, choline precursor, serine biosynthetic pathways and glycine betaine synthesis in salinity stress tolerance. The glycine betaine protects plant from cellular damages and acts as osmoticum under stress condition. Protein interaction network (PIN) analysis demonstrated that 61% of the differentially expressed proteins exhibited positive interactions and 10% of them formed the center of the PIN. Further, The PIN analysis also highlighted the potential roles of the cytochrome c oxidases in sensing and signaling cascades governing salinity stress responses in pigeonpea. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01116-w.

CRISPR-Cas9 directed genome engineering for enhancing salt stress tolerance in rice.

Crop productivity in rice is harshly limited due to high concentration of salt in the soil. To understand the intricacies of the mechanism it is important to unravel the key pathways operating inside the plant cell. Emerging state-of-the art technologies have provided the tools to discover the key components inside the plant cell for salt tolerance. Among the molecular entities, transcription factors and/or other important components of sensing and signaling cascades have been the attractive targets and the role of NHX and SOS1 transporters amply described. Not only marker assisted programs but also transgenic approaches by using reverse genetic strategies (knockout or knockdown) or overexpression have been extensively used to engineer rice crop. CRISPR/Cas is an attractive paradigm and provides the feasibility for manipulating several genes simultaneously. Here, in this review we highlight some of the molecular entities that could be potentially targeted for generating rice amenable to sustain growth under high salinity conditions by employing CRISPR/Cas. We also try to address key questions for rice salt stress tolerance other than what is already known.

Population Structure Analysis and Selection of Core Set among Common Bean Genotypes from Jammu and Kashmir, India.

Understanding the genetic diversity of a crop is useful for its effective utilization in breeding programmes. For better understanding of the genetic variability in common bean, the first and foremost step is to study its genetic diversity. In the present investigation, 138 genotypes of common bean collected from various regions of Jammu and Kashmir, India, representing major common bean growing areas of this region, were evaluated using 23 SSRs. These SSRs were found highly polymorphic and possess high values for various parameters indicating their high discriminatory power. The average PIC value observed was 0.692, with 0.730 as average gene diversity value, and 0.267 as heterozygosity. Twenty-three SSRs produced a total of 251 alleles. The dendrogram generated with un-weighted neighbour joining cluster analysis grouped genotypes into three main clusters with various degrees of sub-clustering within the clusters. The model-based STRUCTURE analysis using 23 SSR markers identified a population with 3 sub-populations which corresponds to distance-based groupings with average F ST value and expected heterozygosity of 0.1497 and 0.6696, respectively, within the sub-population, as such high level of genetic diversity was observed within the population. Further, Core Hunter II was used to identify a core set of 96 diverse genotypes. This core set of diverse 96 genotypes is a potential resource for association mapping studies and can be used by breeders as a material to make desirable genetic crosses to generate elite varieties for the fulfilling global market needs. These findings have further implications in common bean breeding as well as conservation programs.

Unraveling the efficiency of RAPD and SSR markers in diversity analysis and population structure estimation in common bean.

Increase in food production viz-a-viz quality of food is important to feed the growing human population to attain food as well as nutritional security. The availability of diverse germplasm of any crop is an important genetic resource to mine the genes that may assist in attaining food as well as nutritional security. Here we used 15 RAPD and 23 SSR markers to elucidate diversity among 51 common bean genotypes mostly landraces collected from the Himalayan region of Jammu and Kashmir, India. We observed that both the markers are highly polymorphic. The discriminatory power of these markers was determined using various parameters like; percent polymorphism, PIC, resolving power and marker index. 15 RAPDs produced 171 polymorphic bands, while 23 SSRs produced 268 polymorphic bands. SSRs showed a higher PIC value (0.300) compared to RAPDs (0.243). Further the resolving power of SSRs was 5.241 compared to 3.86 for RAPDs. However, RAPDs showed a higher marker index (2.69) compared to SSRs (1.279) that may be attributed to their higher multiplex ratio. The dendrograms generated with hierarchical UPGMA cluster analysis grouped genotypes into two main clusters with various degrees of sub clustering within the cluster. Here we observed that both the marker systems showed comparable accuracy in grouping genotypes of common bean according to their area of cultivation. The model based STRUCTURE analysis using 15 RAPD and 23 SSR markers identified a population with 3 sub-populations which corresponds to distance based groupings. High level of genetic diversity was observed within the population. These findings have further implications in common bean breeding as well as conservation programs.