Compact solar-powered plasma water generator: enhanced on-site aged seed germination with the corona dielectric barrier discharger

Drought, a crucial abiotic stressor, markedly reduces the growth and yield of tomato crops (Solanum lycopersicum L.). Consequently, adopting drought-resistant cultivars and implementing breeding programs to enhance drought tolerance have emerged as enduring solutions to alleviate the adverse effects of drought in various tomato cultivation regions. In this study, 68 tomato accessions from the United States Department of Agriculture (USDA) were assessed in a controlled greenhouse experiment, encompassing both water deficit treatment and a control group subjected to standard watering conditions. The experiment was arranged in a randomized complete block design with three replications. The results of this study pinpointed four accessions PI 365956, PI 584456, PI 390510, and PI 370091, as drought-tolerant accessions. Additionally, high broad-sense heritability was revealed for leaf wilting, leaf rolling, and SPAD chlorophyll content (total leaf chlorophyll). Furthermore, positive correlations were found among parameters associated with leaf wilting, leaf rolling, and SPAD chlorophyll content. The findings of this study provide valuable insights relevant to tomato breeding initiatives, particularly those aimed at fortifying drought tolerance within the elite cultivars of this essential crop.

Bacterial wilt (BW), caused by Ralstonia solanacearum, is one of the devastating diseases of tomatoes (Solanum lycopersicum L.). The use of resistant cultivars and breeding for genetic resistance is the most effective, economical, and environmentally friendly management strategy for this disease. It is necessary to screen diverse germplasm and cultivated genotypes to identify resistant resources and to develop resistant cultivars in tomatoes to combat the changing pathogen isolates. This study evaluated 40 United States Department of Agriculture (USDA) tomato accessions for their BW resistance to R. solanacearum isolate P822 under greenhouse conditions. The tomato plants were inoculated and visually assessed to observe symptoms and disease severity was scored on a scale of 0 to 4 (0 = no leaf wilted, 1 = 25% of leaves wilted, 2 = 50% leaves wilted, 3 = 75% of leaves wilted, 4 = 100% leaves wilted). Five accessions PI 645370, PI 647306, PI 600993, PI 355110, and PI 270210 were observed as BW resistance with PI 645370 showing the greatest resistance. The broad-sense heritability was estimated as 59.9% based on a 0-4 scale of disease incidence and 42.8% based on the disease severity index for BW resistance. Two distinct clusters (sub-populations) were detected among 39 of the 40 accessions, consisting of 3 and 2 BW resistant accessions in each cluster, respectively, suggesting differences in the genetic base in the five resistance accessions. The resistant accessions will contribute significantly to the tomato breeding program to develop new cultivars with BW resistance.