Influence of humates to mitigate nacl-induced adverse effects on ocimum basilicum l.: Relative water content and photosynthetic pigments: Relative water content and photosynthetic pigments

Aqueous extracts of humic substances constitute one of the alternatives in the group of products used in sustainable agriculture. They are fundamentally obtained from recyclable organic sources, such as compost and vermicompost. The objectives of this study were 1) to define the salinity tolerance of two sweet basil varieties submitted to NaCl-stress; 2) to evaluate the effect of humates as mitigator of NaCl-induce adverse effects and 3) to test the criteria that leaf relative water content (LRWC) and photosynthetic pigments are accepted as salinity tolerance indicators. The plants were subjected to three NaCl concentrations (0, 50, 100 mM) and one dilution (1/60 v/v) of humates isolated from vermicompost and a control (distilled water) in a completely randomized design with factorial arrangement with six replications. The study was developed under shade-enclosure conditions. The results showed that there is a differential response among varieties with respect LRWC and chlorophyll content. Napoletano was most NaCl tolerant than Sweet Genovese. The LRWC and chlorophyll content perhaps used as tolerance indicators, while defining the NaCl tolerance of sweet basil varieties. The capacity of humates isolated from vermicompost to mitigate NaCl-induced adverse effects in basil development has been proved, when improve some physiological indicators like LRWC and chlorophyll. The discussion of the differential response among basil varieties subjected to different NaCl concentrations and humates isolated from vermicompost is addressed.