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Sensing stress and activating the downstream signaling pathways is the imperative step for stress response. Lectin receptor‐like kinase (LecRLK) is an important family that plays a key role in sensing stress conditions through lectin receptor and activates downstream signaling by kinase domain. We identified the role of OsLecRLK gene for salinity stress tolerance and hypothesized its role in Na+ extrusion from cell. OsLecRLK overexpression and downregulation (through artificial miRNA) transgenic lines were developed and its comparison with wild‐type (WT) plants were performed overexpression transgenic lines showed better performance, whereas downregulation showed poor performance than WT. Lower accumulation of reactive oxygen species (ROS), malondialdehyde and toxic ion, and a higher level of proline, RWC, ROS scavengers in overexpression lines lead us to the above conclusion. Based on the relative expression of stress‐responsive genes, ionic content and interactome protein, working model highlights the role of OsLecRLK in the extrusion of Na+ ion from the cell. This extrusion is facilitated by a higher expression of salt overly sensitive 1 (Na+/K+ channel) in overexpression transgenic line. Altered expression of stress‐responsive genes and changed biochemical and physiological properties of cell suggests an extensive reprogramming of the stress‐responsive metabolic pathways by OsLecRLK under stress condition, which could be responsible for the salt tolerance capability.

A stock of disomic chromosome substitution (DCS) lines having specific chromosome of wheat variety C591 substituted in the background of rest of Chinese spring chromosomes, were used to analyze grain yield components as a function of enzyme activity of ADP-glucose pyrophosphorylase (AGPase), a starch biosynthesis enzyme in wheat grains. Associations between yield characteristics, grain growth rate (GGR) and AGPase enzyme activity of DCS lines suggested a major involvement of chromosome 3A, 4B, 7D and 2D in a temperature dependent manner. Assessment of AGPase assay at different developmental stages such as 14, 21, 28 days post anthesis (DPA) embodied that gene(s) for this enzyme are present on specific chromosomes and operate at different stages of grain development. The DCS line with 7D chromosome has a major contribution in determining the grain starch content. In this line, AGPase enzyme activity was highest at 21 DPA and was the most crucial determinant in its high GGR. Line 4B performed well at only early stage (14 DPA) suggesting that line 4B AGPase requires a lower temperature range for activation as compared to 7D line. Line 3A had substantially reduced (40%) test weights revealing the presence of few down-regulatory elements on chromosome 3A to reduce the activity of AGPase. The DCS line 2D showed higher test weights and grain number than all other lines ascribed to a consistent AGPase activity along with an efficient mechanism for translocation of photosynthates from source to sink. The chromosome 2D shows positive relation with yield attributes therefore, it can be employed to improve wheat productivity via analytical breeding programme.

RuvBL, is a member of SF6 superfamily of helicases and is conserved among the various model systems. Recently rice homolog of RuvBL has been biochemically characterized for its ATPase and DNA helicase activities, however its involvement in stress is not been studied yet. This study reports the detailed functional characterization of RuvBL homolog of Oryza sativa, under abiotic stress through transgenic approach. An improved Agrobacterium-mediated in-planta transformation method was developed in indica rice to generate the transgenic lines and study was focused on optimization of factors to achieve maximum transformation efficiency. Overexpressing OsRuvBL1a transgenics showed enhanced tolerance under in vivo salinity stress as compared to WT plants. The physiological and biochemical analysis of the OsRuvBL1a transgenic lines showed better performance under salinity and drought stresses. Several stress responsive interacting partners of OsRuvBL1a were identified using Y2H method. Working mechanism for boosting the stress tolerance by OsRuvBL1a has been proposed in this study. This integration of OsRuvBL1a gene in rice genome using in-planta transformation method helped us to achieve the abiotic stress tolerant smart crop. This study is the first direct evidence to show the novel function of RuvBL in boosting abiotic stress tolerance in plants.

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