Mitigation effect of silice on the initial development of peanuts submitted to stress by aluminum and salinity

Abstract

Peanut (Arachis hypogea L.) is an oleaginous crop with great potential for human consumption, production of biofuels and forage, and may expand to new cultivation areas that present limitations to its growth, such as high concentration of aluminum (Al) and salinity. This work was carried out with the objective of verifying if silicon (Si) linked to seed treatment attenuates the effects of salinity and Al toxicity in the initial development of peanut plants. Two experiments were carried out in a completely randomized design, in a 3x2 factorial scheme, with three concentrations of Al3+ (0; 54 and 216 mg.L-1) or three concentrations of salinity (0, 30 and 60 µM of NaCl), in the absence and presence of calcium silicate (0.0 and 200 µM) in the seed treatment, and the seeds were immersed for 40 min in a 1.0 mmol.L-1 calcium silicate solution, with four repetitions per treatment. While the seeds were immersed for 40 min. controls were immersed in distilled water, with four replications per treatment. After the imbibition process, one seed was sown per pot (300 mL), which were filled with coconut powder substrate. Plants were cultivated in nutrient solution for 30 days containing the appropriate treatments. At the end of this period, the growth parameters were verified through the evaluations of height, root length, number of leaflets and shoot and root dry mass. Young peanut plants showed sensitivity to salinity and Al toxicity, with a deleterious effect on growth, evidenced by the drop in plant development, highlighting the results of roots and leaves in the saline stress treatments. Thus, seed treatment with Si contributed to the attenuation of stressors.