Interference of Weeds in Sweet Potato Genotype Growth (Ipomoea batatas (L.) Lam.)

Abstract

The experiment was carried out in the Experimental Area of ​​the Plant Genetic Improvement Sector of the Agricultural Sciences Center of the Federal University of Alagoas (SMGP-CECA-UFAL), in the year 2013, where periods of control and weed coexistence of sweet potatoes were evaluated. The experimental design was carried out in randomized blocks in the 3 x 14 factorial scheme with three replications, with three sweet potato genotypes in 14 periods of interference, and distributed in seven control periods (0, 10, 20, 30, 40, 50 and 60 days after planting - DAP), from which the weeds were controlled, and seven coexistence periods, from which the weeds coexisted with the crop. The evaluations consisted of sweet potato genotype shoot samplings at 30, 60, 90, and 120 days after planting (DAP), using one working area plant per plot in each evaluation stage. In the determination of the leaf area, a mechanical integrator was used, and to obtain the shoot dry mass, the material was taken to a forced air circulation oven at 65 ºC for 72 h, with subsequent weighing. According to the results, it can be observed that, in the coexisting treatments, there was a significant reduction in the shoot growth rates, in comparison to the treatments in which the weeds were controlled, especially the reduction of the leaf area at 120 DAP, where clone 6 and Sergipana showed a reduction of 89.0% and 88.0%, respectively. As for Clone 14, this reduction occurred at 90 DAP, at about 52.0%, which was less expressive, whereas in relation to the shoot dry mass, clones 6, 14, and the Sergipana variety showed a reduction at 120 DAP of 86%, 51%, and 46%, respectively.