SANTOS, J. M. D.; http://lattes.cnpq.br/4978813028952134; SANTOS, Jeferson Miguel Dias.
Abstract:
Understanding the water-soil-plant-atmosphere relationships and their effects on forage
plants is fundamental to optimize the pasture productivity. In this sense, the objective of
this study was to evaluate the influence of agrometeorological variables on growth,
yield and supporter capacity of grass cultivars. The experiment was done at the Center
of Agricultural Sciences of the Federal University of Alagoas, from April to August
2018. The treatments were six grass cultivars: Capim Elefante cv. BRS Kurumi,
Brachiaria decumbens cv. Basilisk, Hybrid Brachiaria cv. Mulatto II, Brachiaria
brizantha cv. Xaraés, Panicum maximum cv. Massai and Panicum maximum cv.
Mombasa The experimental design was randomized blocks with five replications. The
variables analyzed were: agrometeorological (rain, evapotranspiration, air temperature
and photosynthetically active radiation), water balance, leaf area index (IAF), vegetative
canopy height (CH), light intercept index, green and dry matter yield, light extinction
coefficient, water productivity and supporter capacity of grass cultivars. Rainfall from
April to august was (611,9 mm), higher than the reference evapotranspiration (376,3
mm), but due to the irregular distribution of rainfall in that period, there was water
excess (288,8 mm), and hidric deficit (34,4 mm). The intercepted radiation was 103,6
MJ m-2, the LAI and CH were 2,9 and 64,9 cm. green matter (GM) and dry matter
(DM) yield were 6.695,0 and 1.367,1 t ha-1, respectively. The average water
productivity was 0,24 kg of GM per cubic meter of water and maximum supporter
capacity was 6,5 animal units per hectare. The cultivars that produced the most green
and dry matter were BRS Kurumi and Massai, respectively. The cultivars Mombasa and
Massai were the most responsive to water and with the highest carrying capacity.
