Efecto de un regulador de crecimiento de PBZ en el ajuste poblacional de siembra en el cultivo de maíz (Zea mays L.)

Abstract

Maize cultivation is one of the most important grasses in the world due to its direct participation in human and animal nutrition, however, its productive potential begins to explore arguments such as the use of high planting densities, leading to disadvantages in the overgrowth of plants. generated by autoshading. The present investigation was proposed with the objective of evaluating the effect of a PBZ growth regulator on the population adjustment of sowing in the corn crop (Zea mays L). Planting densities of 57000, 71000, 95000 and 140000 plants ha-1 were used. The application of the gibberellin inhibitor (PBZ) was in doses of 0, 1, 2 and 3 cc L-1, in phenological stage V6 and V8 according to the BBCH scale. Plant height, stem diameter, ear insertion height, chlorophyll fluorescence, chlorophyll index, thousand grain weight, number of grains, and yield were evaluated. The relevant results obtained, the height of the plant and the insertion of the ear increased according to the higher planting densities. The stem diameter decreases in relation to the increase in planting densities. With the use of 3 cc PBZ doses, the height of the plants was reduced by approximately 25 cm at planting densities of 140000 plants ha-1. The use of PBZ did not cause an effect on the chlorophyll fluorescence parameters and yields. In conclusion, the use of 3 cc PBZ doses helps to regulate the overgrowth of maize plants when using high planting densities, reducing lodging of the plants and without affecting the productive parameters. In addition, yields increased by more than 140% in relation to commercial planting densities with the use of 140000 plants ha-1.