Impacts of drought stress on crop production can significantly impair farmer's revenue, hence adversely impacting the gross national product growth. For cowpea [Vigna unguiculata (L.) Walp.], which is a legume of economic importance, effects of drought at early vegetative growth could lead to substantial yield losses. However, little has been done with respect to breeding for cowpea cultivars withstanding drought at early vegetative growth. In addition, previous investigations have focused on how plant morphology and root architecture can confer drought tolerance in cowpea, which is not sufficient in efforts to unravel unknown drought tolerance-related genetic mechanisms, potentially of great importance in breeding, and not pertaining to either plant morphology or root architecture. Therefore, the objective of this study was to evaluate aboveground drought-related traits of cowpea genotypes at seedling stage. A total of 30 cowpea genotypes were greenhouse grown within boxes and the experimental design was completely randomized with three replicates. Drought stress was imposed for 28 days. Data on a total of 17 aboveground-related traits were collected. Results showed the following: 1) a large variation in these traits was found among the genotypes; 2) more trifoliate wilt/chlorosis tolerance but more unifoliate wilt/chlorosis susceptible were observed; 3) delayed senescence was related to the ability of maintaining a balanced chlorophyll content in both unifoliate and trifoliate leaves; and 4) the genotypes PI293469, PI349674, and PI293568 were found to be slow wilting and drought tolerant. These results could contribute to advancing breeding programs for drought tolerance in cowpea.

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Tomato brown rugose fruit virus (ToBRFV) is an emerging tobamovirus infecting tomato and pepper crops. First identified in 2014 in the Middle East, ToBRFV has spread rapidly around the world. Being seed-borne, resistance breaking and easy mechanical transmission, ToBRFV can spread quickly in a greenhouse through plant handling. Thus, selecting an effective disinfectant that is capable of deactivating virus infectivity is important. We aimed to identify these effective disinfectants for ToBRFV management in greenhouse tomato production, particularly for total cleaning. A useful disinfectant should be effective against ToBRFV infectivity without major phytotoxic effect on the test plants. In this study, we evaluated 11 disinfectants at various concentrations and assessed their efficacy in ToBRFV treatment on tomato plants that were pretreated with or without SP2700, a known antiviral plant activator of Ningnanmycin. SP2700 treated-plants generated systemic acquired resistance with a delay in symptom expression for 2–3 weeks in comparison to the mock control. Overall, 1% Virocid, 2% Virkon S, 0.25% sodium hypochlorite (5% Clorox bleach), and 2.5% trisodium phosphate (TSP) achieved complete deactivation of ToBRFV with 15 min exposure. However, TSP presented serious phytotoxicity. Our results offer practical solutions to manage this emerging disease affecting tomato production in greenhouses.