Deposition of spray solution and productivity of soybean cultivated in different spatial arrangements

The main purpose of the application of pesticides is the efficient control of insects-pests, diseases and weeds. The spatial arrangement of culture can interfere in the structure of the plant and change plant architecture, creating differentiated conditions for the penetration of the droplets in the canopy. This study aimed to evaluate the effect of different population of plants and row spacing in the deposition of spray solution and productivity of the soybean. It was used a randomized block design in factorial 2x6, with two population of plants (160.000 and 240.000 plants ha-1) and six row spacings (0.30; 0.40; 0.50; 0.60; 0.70m and 0.50m with sowing in crossed lines), with four blocks. It was evaluated time to canopy closure, the percentage of canopy closure, the deposition of spray solution in the upper, middle and lower plant, the ratio of deposition between the upper and lower third of the plant and the crop yield. Treatments with spacings of 0.6 and 0.7m did not reach 100% closure. There was a higher deposition in the lower third in the plots sown in lines cross. The highest grain yield occurred at a spacing of 0.4m. The results indicate that the change in the spatial arrangement can increase the time of closing and/or reduce the total closure of the soybean lines, enabling efficient control of diseases in the plant bottom.

application technology; plant populations; spacing; Glycine max.