Grafting on salt tolerant eggplant rootstocks can be a promising approach for enhancing the salinity tolerance of tomato. In this study, the performance of tomato cv. Kashi Aman grafted on two salt tolerant eggplant rootstocks (IC-111056 and IC-354557) was evaluated against non-grafted control under saline (ECiw 6 and 9 dS m−1) and non-saline (ECiw ~1 dS m−1) irrigation for 2 years. Grafting improved tomato plant performance under salt stress. Moreover, rootstock IC-111056 outperformed IC-354557. An increase in the average fruit yield of grafted plants compared with non-grafted control at 6 and 9 dS m−1 was 24.41% and 55.84%, respectively with rootstock IC-111056 and 20.25% and 49.08%, respectively with IC-354557. Grafted plants maintained a superior water status under saline irrigation, evidenced with the relative water content and chlorophyll SPAD index, along with higher proline and antioxidant enzyme activities (superoxide dismutase, catalase, and ascorbate peroxidase). Rootstocks mediated the partitioning of toxic saline ions in the scions by promoting higher Na+ accumulation (14% of mean accumulation) in the older leaves and lower (24%) in the younger leaves of grafted plants. This resulted in higher K+/Na+ ratios within the younger (active) leaves of the grafted plants. Our study demonstrates that grafting tomato seedlings on selected salt tolerant eggplant rootstocks is a viable alternative for improving plant physiological status and fruit yield under salt stress, through favorable modulation of salt ion partitioning in the scions.

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The present investigation was conducted on thirty genotypes of mungbean to evaluate genetic variability, character association and genetic divergence for eleven seed quality traits for the identification of most diverse and promising genotypes. The genotypes differed significantly for all characters under study. Higher genotypic and phenotypic coefficient of variation was observed for electrical conductivity test, germination after accelerating ageing (96 hr), seedling vigour index II and seedling dry weight. High heritability coupled with high genetic advance was recorded for seedling dry weight, seedling vigour index I, seedling vigour index II, electrical conductivity, germination after accelerating ageing (48 hr), germination after accelerating ageing (72 hr), germination after accelerating ageing (96 hr). Association analysis indicated that standard germination showed a significant and positive correlation with shoot length, root length, seedling length, seedling dry weight, seedling vigour index I, seedling vigour index II and germination after accelerating ageing (48, 72 and 96 hr). D2 analysis grouped 30 genotypes into 6 clusters. Cluster pattern revealed that cluster I and V were the largest ones with eight genotypes, followed by cluster III and VI with four genotypes and cluster II and IV with three genotypes each. The highest contribution toward the total genetic divergence was recorded for vigour index I, electrical conductivity, shoot length, root length and seedling dry weight. Selection index (I) aimed at selection on several characters simultaneously indicated that genotypes, LGG-460, MH-805, Pusa-0672, IPM-06-5, TBM-11, EC-581523, KM-2241, GP-69, RMG-991 and MH-934 had performed better and were important for further breeding programme aimed at improvement of yield.

Salinity stress is a major constraint to sustainable crop production due to its adverse impact on crop growth, physiology, and productivity. As potato is the fourth most important staple food crop, enhancing its productivity is necessary to ensure food security for the ever-increasing population. Identification and cultivation of salt-tolerant potato genotypes are imperative mitigating strategies to cope with stress conditions. For this purpose, fifty-three varieties of potato were screened under control and salt stress conditions for growth and yield-related traits during 2020. Salt stress caused a mean reduction of 14.49%, 8.88%, and 38.75% in plant height, stem numbers, and tuber yield, respectively in comparison to control. Based on percent yield reduction, the genotypes were classified as salt-tolerant (seven genotypes), moderately tolerant (thirty-seven genotypes), and salt-sensitive genotypes (nine genotypes). Seven salt-tolerant and nine salt-sensitive genotypes were further evaluated to study their responses to salinity on targeted physiological, biochemical, and ionic traits during 2021. Salt stress significantly reduced the relative water content (RWC), membrane stability index (MSI), photosynthesis rate (Pn), transpiration rate (E), stomatal conductance, and K+/Na+ ratio in all the sixteen genotypes; however, this reduction was more pronounced in salt-sensitive genotypes compared to salt-tolerant ones. The better performance of salt-tolerant genotypes under salt stress was due to the strong antioxidant defense system as evidenced by greater activity of super oxide dismutase (SOD), peroxidase (POX), catalase (CAT), and ascorbate peroxidase (APX) and better osmotic adjustment (accumulation of proline). The stepwise regression approach identified plant height, stem numbers, relative water content, proline content, H2O2, POX, tuber K+/Na+, and membrane stability index as predominant traits for tuber yield, suggesting their significant role in alleviating salt stress. The identified salt-tolerant genotypes could be used in hybridization programs for the development of new high-yielding and salt-tolerant breeding lines. Further, these genotypes can be used to understand the genetic and molecular mechanism of salt tolerance in potato.

Production of many crops, including onion, under salinity is lagging due to limited information on the physiological, biochemical and molecular mechanisms of salt stress tolerance in plants. Hence, the present study was conducted to identify salt-tolerant onion genotypes based on physiological and biochemical mechanisms associated with their differential responses. Thirty-six accessions were evaluated under control and salt stress conditions, and based on growth and bulb yield. Results revealed that plant height (6.07%), number of leaves per plant (3.07%), bulb diameter (11.38%), bulb yield per plant (31.24%), and total soluble solids (8.34%) were reduced significantly compared to control. Based on percent bulb yield reduction, seven varieties were classified as salt tolerant (with <20% yield reduction), seven as salt-sensitive (with >40% yield reduction) and the remaining as moderately tolerant (with 20 to 40% yield reduction). Finally, seven salt-tolerant and seven salt-sensitive accessions were selected for detailed study of their physiological and biochemical traits and their differential responses under salinity. High relative water content (RWC), membrane stability index (MSI), proline content (PRO), and better antioxidants such as super oxide dismutase (SOD), peroxidase (POX), catalase (CAT), and ascorbate peroxidase (APX) were observed in tolerant accessions, viz. POS35, NHRDF Red (L-28), GWO 1, POS36, NHRDF Red-4 (L-744), POS37, and POS38. Conversely, increased malondialdehyde (MDA) and hydrogen peroxide (H2O2) content, reduced activity of antioxidants, more membrane injury, and high Na+/K+ ratio were observed in sensitive accessions, viz. ALR, GJWO 3, Kalyanpur Red Round, NHRDF Red-3 (L-652), Agrifound White, and NHRDF (L-920). Stepwise regression analysis identified bulb diameter), plant height, APX, stomatal conductance (gS), POX, CAT, MDA, MSI, and bulb Na+/K+ ratio as predictor traits accounting for maximum variation in bulb yield under salinity. The identified seven salt-tolerant varieties can be used in future onion breeding programs for developing tolerant genotypes for salt-prone areas.