Seletividade de diferentes doses de fluxofenim e metcamifen sobre os parâmetros de germinação de sementes de capim Marandú

Abstract

The seed treatment with safeners has demonstrated selectivity potential to some herbicides, which can become an alternative to the utilization of graminicides in pasture areas whose influence on germination parameters and seed quality are not elucidated. Therefore, the aim was to evaluate the protective effect of fluxofenim or metcamifen on germination parameters of Urochloa brizantha cv. Marandu seeds. The experiment was carried out in the laboratory, with four replications of 50 seeds per Transparent plastic boxes in eleven treatments, respectively; seeds without any type of coating (Untreated); Benefic at 20, 40, 80, 160 e 320 mL; Epivio C at 20, 40, 80, 160 e 320 mL, all rates related by 100 kg of seeds. The effect of the different rates was evaluated by the percentage of seed germination (G), seed germination speed index, initial (TI), medium (TM) and final (TF) times of germination, germinations synchrony (S) and relative frequency of germinations over the 36 days that germination lasted. The values of G, IVG, TI, TM, TF and S were statistically analyzed by Test F and, when significative, the means of treatments compared by Scott-Knott Test at 5% probability. The relative frequency of germinations results was analyzed according to unimodality or polymodality of each polygon graphically plotted by Origin 8.5.1 SR1 program. With the obtained results it is possible to conclude that the safeners fluxofenim and metcamifen both used at 20, 40, 80 160 and 320 by 100 kg of seeds are selective to seed covering of Urochloa brizantha cv. Marandu.