Efeito de fertilizante organomineral no desenvolvimento de gramíneas do gênero Urochloa

Abstract

Tropical grasses present distinct growth and development patterns, influenced by their genetic characteristics and environmental conditions. The use of organomineral fertilizers can enhance the productivity of these species, which, due to their particularities, can respond differently to the application of these products. The objective of this study was to analyze the effect of organomineral fertilizer on the development of grasses of the genus Urochloa, considering different growth and production parameters. A completely randomized design with a 6 × 2 factorial scheme and 5 replications was used. Six grasses (Urochloa brizantha cvs. Ipyporã, Xaraés, Piatã and Marandú; Urochloa decumbens cv. Basilisk; Urochloa ruziziensis) with or without application of FTGrass®, totaling 60 experimental plots (pots with a capacity of 10 dm³ of soil). The experiment was conducted in a greenhouse. Thirteen days after emergence, thinning was performed, leaving 3 plants per pot. The organomineral fertilizer (FTGrass®) was applied 10 days after cutting, by foliar spraying, using a solution in the proportion of 1:100, using 5 ml pot-1 . Morphogenic characteristics, dry mass production and root productivity were evaluated. For statistical analyses, Tukey's test was used at 5% significance, with the aid of R software. No interaction effect (P>0.05) grass × FTGrass® was observed for any of the variables. For the variable leaf elongation rate, a difference (P<0.05) was observed only for the cultivars, being seen that Marandu and Xaraés presented the highest values compared to the cultivars Decumbens, Piatã and Ruzizienses. There was a difference (P<0.05) in the leaf blade proportion among the cultivars, with the cultivars Marandu, Piatã, Xaraés and Ipyporã standing out, presenting the highest leaf blade proportions. For the proportion of dead material, a difference (P<0.05) was observed among the cultivars, since higher values were verified for the cultivars Decumbens and Ruzizienses, and lower value for the cultivar Xaraés. There was a variation (P<0.05) in the leaf blade: stem ratio among the cultivars, Marandu presented the highest leaf blade: stem ratio, not differing from the cultivar Xaraés. Among the variables analyzed, only root production did not differ (P>0.05) among the cultivars. Xaraés grass stood out, with a superior performance in relation to the other grasses. The use of organomineral fertilizer, in the proportion of 1:100 and applied 10 days after cutting, does not provide significant improvements in the growth and development of forage plants of the genus Urochloa.