| Autor: |
Praxedes SSC; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Ferreira Neto M; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Loiola AT; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Santos FJQ; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Umbelino BF; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Silva LA; Center of Technology and Natural Resources, Federal University of Campina Grande-UFCG, Campina Grande 58428-830, Brazil., Moreira RCL; Center of Technology and Natural Resources, Federal University of Campina Grande-UFCG, Campina Grande 58428-830, Brazil., Melo AS; Department of Biology, Universidade Estadual da Paraíba, Campina Grande 58429-500, Brazil., Lacerda CF; Department of Agricultural Engineering, Federal University of Ceará, Fortaleza 60440-593, Brazil., Fernandes PD; Center of Technology and Natural Resources, Federal University of Campina Grande-UFCG, Campina Grande 58428-830, Brazil., Dias NDS; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil., Sá FVDS; Department of Agronomic and Forest Sciences, Federal Rural University of the Semi-Arid-UFERSA, Mossoró 59625-900, Brazil. |
| Abstrakt: |
Cowpea is the main subsistence crop-protein source-for the Brazilian semi-arid region. The use of salt-stress-tolerant varieties can improve crop yields. We evaluated the effect of irrigation with brackish water on the growth, photosynthetic responses, production, and tolerance of fifteen traditional varieties of cowpea. The experiment was conducted in randomized blocks, in a 15 × 2 factorial scheme, composed of 15 traditional varieties of cowpea and two salinity levels of irrigation water (0.5 and 4.5 dS m -1 ), with five replicates. Plants were grown in pots containing 10 dm 3 of soil for 80 days. The reduction in the photosynthetic rate of cowpea varieties occurs mainly due to the decrease in stomatal conductance caused by salt stress. Salt stress increased the electron transport rate and photochemical quenching of cowpea varieties, but stress-tolerant varieties increased the CO 2 assimilation rate and instantaneous carboxylation efficiency. The Ceará, Costela de Vaca, Pingo de Ouro, Ovo de Peru, and Sempre Verde varieties are tolerant to salt stress. Salt stress decreases 26% of the production of tolerant varieties to salt stress and 54% of susceptible varieties. The present findings show the existence of variability for saline stress tolerance in traditional varieties of cowpea and that Ceará, Costela de Vaca, Pingo de Ouro, and Ovo de Peru varieties are more suitable for crops irrigated with saline water. |
