Curly lettuce development, nutrient absorption and salinization tolerance in response to an aerobic biofertilizer produced from agro-industrial residues

Abstract

Biofertilizers stimulate natural processes to increase and benefit nutrient absorption, abiotic stress tolerance and increased yield when applied to plants. The production of biofertilizers from organic residues is a sustainable way to reduce these materials through recycling. The aim of this work was to define the biofertilization management based on concentrations and doses using a non-commercial aerobic biofertilizer on three newly emerged Brazilian lettuce cultivars. Consequently, this study will help to improve organic lettuces yields in the country. The experiments were conducted in a greenhouse. The soil used for cultivation was a clayey Rhodic Ferralsol. Due to the high electrical conductivity (EC) observed in the biofertilizer a first experiment was conducted to determine the optimum concentration (0%, 5%, 10%, 15%, 20% and 100%) for the three lettuce cultivars (BRS Leila, BRS Lélia and BRS Mediterrânea). After finding the best concentration, a second experiment was developed to estimate the optimum dose of the biofertilizer based on the nitrogen requirement (N) for this crop (0 kg ha-1 of N, 50 kg ha-1 of N, 100 kg ha-1 N, 150 kg ha-1 N and 200 kg ha-1 N). The experimental design was completely randomized (DIC) with a factorial scheme. The results showed that 5% concentration of biofertilizer presented better results for the development of BRS Mediterrânea and BRS Lélia. BRS Leila presented better development when fertilized with the 10% biofertilizer concentration. The dose of 150 kg ha-1 of N allowed a better development of lettuce and greater supply of nutrients to the plants.

Stability Evaluation for Heat Tolerance in Lettuce: Implications and Recommendations

“…Considering the AMMI2 model, the cultivars BRS Mediterrânea and Simpson were related to E1 and E3; two pathways could explain these results. As the first cultivar showed a high mean of days to the first anthesis, this association could be explained by its production under high temperatures [ 42 ]. An opposite trend is valid for Simpson, which is not adapted to high temperatures, and this cultivar was negatively related to the hottest environments.…”