Lactofen e citocininana produtividade de grãos em soja

Abstract

In the last decades there has been a great advance in the cultivation of soybeans in Brazil, with an increase of about 1 million hectares year -1 . There were also gains in productivity due to the launch of new and more productive cult ivars, as well as improved management. New technologies are constantly emerging that must be validated by research. An example is the use of lactofen, which has been applied by producers, in the most varied conditions, aiming at increasing productivity. The aim of this study was to study the influence of the use of lactofen as a growth regulator and phytohormone kinetin in the morpho-agronomic characters and in the yield of soybean cultivars with different maturity groups. The experiments were conducted in three locations, with the crops located in the municipalities of Lavras-MG, Itutinga-MG and Nazareno-MG, during the 2017/2018 agricultural harvest. The experimental design was a randomized complete block design (5 × 6), with four replications. The main plo t corresponded to five treatments: lactofen (144 g ha -1 ), lactofen + kinetin (144 + 0.5 g ha -1 ), kinetin (0.5 g ha -1 ), apical buds and control; the sub plot was composed of six cultivars: M6410 IPRO, IPRO M5917, NS6909 IPRO, NS7670 RR, BMRO Launches IPRO, and Produces IPRO. The treatments were applied in post-emergence, when the plants were in the V6 phenological stage. The evaluations of lodging, height of plants, number of nodes per plant, number of branches per plant, number of vegetables per plant, number of grains per plant, mass of 100 grains and productivity were performed. Based on the results obtained, it was concluded that the application of lactofen at the dose of 144 g ha -1 in V6 caused modifications in the agronomic morph characteristics of the studied cultivars; being that the application of lactofen resulted in an increment of 5.2 sacks of soybean, when compared to the control treatment. The most productive cultivars were NS 7670 RR and M 6909 IPRO.