Bioestimulantes aplicados em sementes e plantas de milho doce em condições de estresse abiótico

Abstract

Sweet corn seeds have low physiological quality, attributed mainly to their high sugar content and low starch content, which makes them more susceptible to mechanical damage, pests and initials diseases, as well as greater susceptibility to hidrical and thermal stress conditions. To minimize the effect of low-quality sweet corn seeds, two experiments were carried out to verify the effect of the use of biostimulants and establishment of seedlings under stress conditions. The first one evaluated the effect of biostimulants in the treatment of the seeds and in the second the cumulative effect of the treatment of the seeds, plus the foliar application in the vegetative stage of the plant. Seed treatment was evaluated using 3 biostimulants (Booster®, Stimulate® and Vitakelp®), three stress conditions (-0.3, -0.6 and -0.9 Mpa) and two temperatures (25 and 30 W). First germination, germination, emergency counts, emergency speed index and cold test were used. In the second experiment, the same 3 biostimulants were used in 3 water retention capacity (40, 50 60%), and two application methods (via seeds and plant spraying). Plant height, stalk diameter, root dry matter and total dry matter were evaluated. There is a positive effect of the use of biostimulants when in adverse conditions, such as hidric deficit and high temperatures. The use of Booster® biostimulants positively affects the germination and vigor of super sweet corn seeds. The super sweet corn cultivars BRS Vivi and Tropical Plus respond differently to the use of biostimulants. The application of biostimulants is more efficient when used in seed treatment.