População de plantas e produtividade da cultivar de soja BMX Zeus IPRO®

Abstract

Although soybean has plants with excellent plasticity, which adapts in response to different plant arrangements, new cultivars need to be validated in relation to the optimal population to obtain high yields. An ideal population allows to reduce intraspecific competition by increasing the interception of solar radiation and nutrient absorption. Therefore, this work aimed to evaluate the yield components and productivity of the cultivar Brasmax Zeus IPRO® in different plant populations in the sowing line. The study was conducted at the Experimental Station of the Federal Technological University of Paraná (UTFPR), Campus Dois Vizinhos. The experimental design used was a randomized block design, with five treatments, namely: 4 (88,888 plants ha­1); 6 (133,333 plants ha­1); 8 (177,777 plants ha­1); 10 (222,222 plants ha­1) and 12 (266,666 plants ha­1) plants per linear meter with four replications. The experimental plots consisted of 5 lines of 5 meters in length, spaced 0.45 m between lines, totaling 20 plots, 3 lines of 3 meters in length were sampled to obtain yield, and 10 plants were analyzed to obtain yield components. Data were subjected to analysis of variance, and the plant population factor per linear meter was evaluated with a regression analysis, with significant values of 5% (p < 0.05), using SISVAR software. The yield components (height of insertion of the first pod, number of reproductive nodes, number of branches, number of pods and number of grains) were negatively influenced by the increase in plant population. The thousand grain mass and plant height were not influenced by the stand. For productivity, for each plant increased between the population of 4 and 12 plants m1 there was an increase of 250 kg of soybean per hectare, with a linear response to the increase in population. The productivity with 12 plants m­1 was 5,878.3 Kg ha­1, while with 4 plants m­1, it was obtained 3,656.97 Kg ha­1, that is, a reduction of 37.79% or 2,221. 63 kg from 12 to 4 plants per linear meter. It is concluded that the yield components number of spawning nodes, number of branches, number of pods and number of grains decrease as plant population increases. The height of insertion of the first pod increases as the population increases. The average plant height and mass of a thousand grains are not influenced by population. There was a linear increase in productivity as the population of soybean plants increased.