Host Suitability of Weeds to the Root Lesions Nematoid in Soybean Areas in the North of Goias, Brazil

Several studies have done more on weed and nematode hosts. It is important to know a host of weeds and P. brachyurus in areas cultivated with soy. This nematode can stay in weed roots even in the absence of plants grown in the off-season, making it difficult to control them. The objective was to evaluate the host suitability of emerged weed species in cultivated areas with a soybean crop to the P. brachyurus nematode under natural infestation conditions. The surveys were conducted in commercial properties located in the municipalities of Campinorte and Rialma, both in the northern region of the state of Goias, Brazil under the no-tillage and conventional system, respectively, with a history of high nematode population densities. We evaluated 19 weed species with the highest expressivity in the properties. The population densities of the nematode ranged RFom 23 to 17,113 and 55 to 4,221 specimens per 10 grams of roots respectively. All as weed species evaluated as hosts of P. brachyurus. As species, Hyptis suaveolens, Sida cardifolia, Senna occidentalis, Coneyza canadensis and Commelina benghalensis had low population densities.