Salinity is one of the important abiotic stress factors that limit crop production. Common bean, Phaseolus vulgaris L., a major protein source in developing countries, is highly affected by soil salinity and the information on genes that play a role in salt tolerance is scarce. We aimed to identify differentially expressed genes (DEGs) and related pathways by comprehensive analysis of transcriptomes of both root and leaf tissues of the tolerant genotype grown under saline and control conditions in hydroponic system. We have generated a total of 158 million high-quality reads which were assembled into 83,774 all-unigenes with a mean length of 813 bp and N50 of 1,449 bp. Among the all-unigenes, 58,171 were assigned with Nr annotations after homology analyses. It was revealed that 6,422 and 4,555 all-unigenes were differentially expressed upon salt stress in leaf and root tissues respectively. Validation of the RNA-seq quantifications (RPKM values) was performed by qRT-PCR (Quantitative Reverse Transcription PCR) analyses. Enrichment analyses of DEGs based on GO and KEGG databases have shown that both leaf and root tissues regulate energy metabolism, transmembrane transport activity, and secondary metabolites to cope with salinity. A total of 2,678 putative common bean transcription factors were identified and classified under 59 transcription factor families; among them 441 were salt responsive. The data generated in this study will help in understanding the fundamentals of salt tolerance in common bean and will provide resources for functional genomic studies.

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In wheat ( Triticum aestivum L.), embryogenic callus formation comprises suppression of precocious germination by the zygotic embryo and the initiation of dedifferentiated cellular proliferation within it. Embryogenic calli are induced by treating immature embryos with 2,4-dichlorophenoxyacetic acid (2,4-D). Upon withdrawal from 2,4-D, somatic embryos develop from the periphery of the callus. Prior to visible callus formation, there is a striking induction of "germin-like" oxalate oxidase ("gl-OXO": EC 1.2.3.4) gene expression. Accumulation of gl-OXO mRNA is rapidly stimulated upon auxin treatment, with a consequent development of apoplastic enzyme activity producing H(2)O(2) within the cell wall. Within the dedifferentiated calli, gl-OXO enzyme activity becomes widespread over the surface of embryogenic calli. Differentiation of somatic embryos is initiated in regions of densely cytoplasmic, meristematic cells that are marked by highly localised expression of gl-OXO activity within these embryogenic cell masses. We suggest that this localised generation of H(2)O(2) by gl-OXO promotes peroxidative cross-linking of cell wall components, thereby preventing cellular expansion and maintaining these cell masses in an embryogenically competent condition.

Seven genotypes of winter durum wheat {Triticum durum Desf,) were cultured to establish an efficient method of callus formation and plant regeneration from mature embryo culture, and to compare the responses of immature and mature embryo cultures. Immature embryos were aseptically dissected from seeds and placed, with the scutellum upwards, in dishes containing Murashige and Skoog's (MS) mineral salts and 2mg 2,4-dichlorophenoxyacetic acid (2,4-D) per litre, Calli and regenerated plants were maintained on 2,4-D-free medium. Mature embryos were moved slightly on the imbibed seeds. For callus formation, the seeds with moved embryos were placed, furrow downwards, in dishes containing 8 mg 2,4-D per litre. The developed calli and regenerated plants were maintained on the MS medium. Plants regenerated from both embryo cultures were vernalized and grown to maturity in soil. Variability was observed among the wheat genotypes tested for various culture responses in both explant cultures. Callus induction rate and regeneration capacity of callus were independent of each other. Mature embryos have a low frequency of callus induction but a high regeneration capacity. Considering availability, rapidity and reliability, this form of mature embryo culture can be used as an alternative method for immature embryo culture.