Effect of Artificial Detasseling and Defoliation on Maize Seed Production

摘要

The objective of this work was to evaluate the effect of artificial detasseling and defoliation on the production of Pioneer 30F90 simple hybrid corn ( Zea mays L.) seeds. The experiment was set up in a randomized complete block design, consisting of seven treatments (Control; detasseling; detasseling + defoliation of the top leaf; detasseling + defoliation of the two upper leaves; detasseling + defoliation of the three upper leaves; detasseling + defoliation of the upper four leaves; detasseling + defoliation of the upper five leaves), with 4 replicates. The plots were composed of 6 spaced rows of 0.90 cm by 6.00 m in length. At the time of the issue of 50% of the tassel were carried out the treatments. For the evaluations the two central lines of each plot were collected, eliminating 1.00 m from each end, totaling a useful area of 7.2 m2. At harvest, the crop presented a final stand of 5 plants m2 (50000 ha-1). According to the results obtained, it was concluded that the detasseling positively influenced the production components, due to the decrease of the auto-shading. The higher the level of defoliation, the lower the active photosynthetic area of the plant, and consequently the lower the productivity. The most affected production components in defoliation are grain numbers in the row, grain numbers in the ear and weight of 1000 grains. detasseling and defoliation do not interfere with the germination of corn seeds.