Efeito da giberelina (Ga3) na germinação e desenvolvimento inicial do sorgo

Abstract

Sorghum (Sorghum bicolor) is widely cultivated in the Cerrado region of Piauí, standing out as a strategic option for the second harvest in dryland conditions, a period subject to a greater probability of abiotic stresses that can cause several morphological and physiological disorders in the crop. Due to these conditions, the improvement of practices that encourage uniform germination and a vigorous initial establishment, such as the use of the phytohormone gibberellin, is essential for the performance of the crop. Therefore, the study aimed to evaluate the effect of gibberellin (GA3) application on the germination and initial development of grain sorghum cultivars. The study was conducted in the field and in a greenhouse at the IFPI School Farm - Uruçuí Campus. The treatments were arranged in a randomized block design, in a 2 x 4 splitplot scheme, corresponding to two sorghum cultivars (1G100 and MG2220) and four gibberellin doses (0, 5, 10 and 15 g/100 kg of seeds), with four replicates. The variables analyzed included emergence, emergence speed index, plant height, and dry mass of the aerial part and root. The results indicated that the application of gibberellin favored the germination and initial development of sorghum cultivars, at doses of up to 7.6 g/100 kg, with emphasis on seedling height; and did not promote significant effects on the variables emergence speed index, dry mass of the aerial part and root