Avaliação da hospedabilidade de plantas ao pratylenchus brachyurus oriundo de lavouras de soja

Abstract

Brazil is a country that is under agricultural development and has as one of the main foundations of the economy the production of grains for export. Soybeans are the main cultivated species in the country, this because of its great importance for humanity and how every culture has encountered many problems when it comes to plant health. Nematodes are one of the main causes of loss of productivity in soybean, becoming a limiting factor for a good production. Among so many nematodes that cause disorders to the sojicultores, is the Pratylenchus brachyurus. This work was carried out with the objective of evaluating the hostability of species of agricultural interest and weeds to P. brachyurus from soybean growing areas. The experiment was conducted in a greenhouse, at the Federal University of Mato Grosso - Araguaia University Campus, Barra do Garças, MT and the analyzes carried out in the Phytopathology laboratory of the same. A randomized complete block design was used with cultivation of the following cultures: Millet ADR 300, Millet ADR 300 Salvo, crotalaria (Crotalaria spectabilis), capim colchão (Digitaria sp.), goose grass (Eleusine indica), hairy beggarticks (Bidens pilosa), caupi Bean BRS-Tumucumaque (Vigna unguiculata), chia (Hispanic Salvia), okra Santa Cruz 47 (Abelmoschus esculentus), being eight replications per treatment. Plastic bags of 3.0 liters were used with the seeding of five seeds per bag. The soil of each bag contained the initial population of 766.7 individuals of P. brachyurus. At the end of 58 days, the fallowing variables were evaluated: P. brachyurus population in soil, root and total, fresh root mass, P. brachyurus population per gram root of plants and breeding factor (RF) of P. brachyurus in plants. In this experiment the plants that showed to be worse hosts to P. brachyurus were C. spectabilis and B. pilosa, because they obtained FR <1.0, therefore, the presence of the same ones in areas of soybean planting is favorable, once which reduce the population of the species P. brachyurus.