Interaction between thidiazuron and Azospirillum brasilense on yield characteristics and productivity of rice

Abstract

In rice, the use of the bacterium Azospirillum brasilense has shown to be very useful for the crop, being able to increase the final productivity of the same or reduce the need for nitrogen in topdressing. It has recently been noted that there are other regulators that perform other functions, such as thidiazuron (TDZ), a cytokinin-like substance that has been shown to significantly increase upland rice productivity. Thus, the present work aimed to verify the effect of the interaction between the foliar application of A. brasilense and thidiazuron doses applied at the occasion of the tillering of the plants on the productive aspects and crop productivity. The experiment was carried out in the agricultural years of 2015/16 and 2016/17, at the UNESP Teaching, Research and Extension Farm belonging to the Engineering Faculty of Ilha Solteira - UNESP, located in the municipality of Selviria, MS. The experimental design was a randomized complete block design with a 2 x 4 factorial scheme with four replicates. The treatments were the combination of the presence or absence of A. brasilense foliar application with doses of TDZ (0, 0.5, 1.0 and 1.5 g ha(-1)) applied to upland rice cultivar BRS Esmeralda. Based on the results obtained for plant height, number of panicles per square meter, total number of grains and fertility of spikelets, mass of 100 grains and grain yield, it was concluded that, in the two agricultural years observed, there were no interaction and individual effects of the foliar application of the bacteria, and of the TDZ doses used at the time of tillering in the BRS Esmeralda cultivar.