Growth, gas exchanges and production of beet CV. katrina under organo-mineral fertilization

Abstract

The beet culture has great economic and food importance in the world, especially with respect to energy generation. In Brazil the culture is still little studied, lacking studies in all stages of production of culture, mainly in the management of fertilization. This study aimed to evaluate the effect of organo-mineral fertilization on growth, gas exchanges and production of beet, cv. Katrina. The experiment was conducted under field conditions in the municipality of Pombal-PB, Brazil, from September to December 2015, in a randomized block design. The treatments were arranged in a 4 x 2 factorial scheme and corresponded to four periods of fermentation of the biofertilizer (10, 20, 30 and 40 days) applied in soils with and without mineral fertilization, with four replicates and 18 plants evaluated per plot. Plants were conducted for 70 days after transplanting, in 15-cm-high, 1-m-wide beds. During this period, plant growth, gas exchanges and production components were evaluated. The application of mineral biofertilizer fermented for 20 to 30 days, associated with mineral fertilization with 36 g m^-2 of P₂O₅, 18.0 g m^-2 of K₂O and 14 g m^-2 of N at planting, promoted better performance of growth, gas exchanges and production of beet plants. In the soil without mineral fertilization, it is recommended to use the longest biofertilizer fermentation periods, 30 to 40 days, for beet cultivation.