Pratylenchus brachyurusparasitism on soybean: effects on productivity, vegetative and nematological parameters and chemical properties

The aim of this work was to evaluate the effect ofPratylenchus brachyurusparasitism on the vegetative and nematological parameters of soybean, as well as on the productivity, composition, isoflavone profile and antioxidant capacity of the grains. A completely randomized design with four nematode inoculum levels (0, 500, 1000 and 2000) was used. Plants withoutP. brachyuruspresented higher productivity and lower values for vegetative parameters. Maximum reproduction ofP. brachyurus(17,493 nematodes) was observed with the initial population of 1444 nematodes. With increasing inoculum level, the moisture, fiber, lipid and stachyose contents were reduced, while ashes, fructose, and sucrose levels were increased. The total phenolic compounds, total flavonoids and antioxidant capacity increased until an inoculum level of 1000 nematodes was reached. The highest concentration of isoflavones, namely, daidzein, genistin, genistein, glicitin, and acetyl-glicitin was detected at the inoculum level of 2000 nematodes. Therefore, the inoculum levels ofP. brachyurusaffected soybean development, as well as, the chemical composition of the grains.