Qualidade de sementes de cevada submetidas a maturação com herbicidas

Abstract

Barley (Hordeum vulgare) is an alternative to a series of crops in the South of Brazil, being destined to the production of malt in the great majority. This is one of the agricultural crops more sensitive in the physiological maturity. The desiccation of the crop in the physiological maturity is an alternative to anticipate the harvest, thus guaranteeing the quality of the 6 harvested seeds. Thus, the objective was to make the applications of doses of herbicides maturing in the barley and the effects on the physical and physiological quality of the seeds of the crop. Two doses of herbicides were applied: ammonium glufosinate (350 and 400 g ha-1), glyphosate (540 and 1080 g ha-1 of ea), paraquat (300 and 400 g ha-1), diquat (200 and 400 g ha-1), in addition to the natural and artificial drying of 45 ° C. Physiological quality evaluation: germination, IVG, accelerated aging, seedling length and physical quality; weight of one thousand seeds, hectoliter weight, electrical conductivity. In addition to the physical and physiological parameters, the protein content of the seeds was determined. The means were submitted to analysis of variance by the F test, compared to the Scott Knott test (p ≤ 0.05). Desiccation with glyphosate produced the greatest losses of germination and vigor. The use of paraquat and diquat at higher doses also resulted in loss of seed quality. The artificial drying caused the fall of the force and the increase of the fissures, through the electrical conductivity test. The best herbicide was ammonium-glufosinate when used at a dose of 350 g ha-1 we demonstrated equal to drying natural in most of the tests evaluated.