Interferência de plantas daninhas em genótipos de batata doce (Ipomoea batatas (L.) (Lam.))

Abstract

The degree of weed interference depends on factors related to their own culture, weed community , the environment, the period in which they live and available resources (water, nutrients and light). Thus, this study aimed to identify the communities of weeds present in the areas planted with sweet potato genotypes, determine the critical period of interference prevention (PCPI) of the weeds, and to assess the growth of these genotypes to the detriment of undergoing treatment. The assay was performed in the experimental area of the Breeding Industry of Agricultural Sciences Center Plants of the Federal University of Alagoas (SMGP - CECA - UFAL) in 2013 were evaluated in control periods and weed coexistence with the sweet potato genotypes (variety Sergipana and clones 6 end14). The experimental design was a randomized block in a factorial 3 x 14 with three replications , three sweet potato genotypes in 14 periods of control, over seven periods of control, (0 , 10, 20 , 30, 40, 50 and 60), from which the weeds were controlled and seven periods of coexistence, (0 , 10, 20 , 30, 40 , 50 and 60), from which the weeds lived with culture. The main found families were Poaceae and Asteraceae , totaling 14 families, consisting of 26 weed species. The species Richardia grandiflora Cham. & Schltdl. (White Poaia), Ageratum conyzoides L. (Mentrasto) and Eleusine indica (L.) Gaertn. (Grass -foot- of - chicken) were the most prevalent, with higher percentages of relative frequency, abundance, importance value index, density and biomass accumulation, expressing greater power of competition in relation to other species in cultivated areas three sweet potato genotypes. The PCPI was from 23 to 42 DAP for Sergipana range of 24 to 46 DAP for Clone 6 and 17 to 40 DAP for Clone 14. There was a 65% reduction in productivity when genotypes were maintained in coexistence with the weeds throughout the cycle, but also showed a decrease in growth rates of sweet potato.