Pasteuria nishizawae no controle do nematoide de cisto da soja

Abstract

The soybean crop loses 10.6% in production, at world levels, hosting plantparasitic nematodes. The nematode nematode of soybean, one of the most harmful to the crop, was detected in Brazil in the 1991/1992 crop. The fact of forming cysts makes it difficult to control because it remains for several years in the soil. This species also reproduces by amphimixia, increasing the genetic variability of its population and restricting the available resistant cultivars. Therefore, it is necessary to increase new control measures to establish the management of this pathogen. The use of Pasteuria spp. For the biological control of nematodes is a viable strategy. The objective of this work was to evaluate the effectiveness of the isolate A19824 of P. nishizawae in the treatment of soybean seeds for the control of Heterodera glycines. The experiment was conducted in a greenhouse, with a completely randomized design, 10 treatments, four replicates and three evaluation periods (30, 60 and 90 days after nematode inoculation). The treatments were: Clariva (P. nishizawae), Vitazyme, Avicta 500 FS, Clariva + Vitazyme, Clariva + Avicta 500 FS, Avicta 500 FS + Vitazyme, Clariva + Avicta 500 FS + Vitazyme, Cropstar + Derosal Plus. Females and cysts, eggs per female and / or cyst counts at 30, 60 and 90 days after nematode inoculation were performed. The number of cysts and the number of eggs per cyst of H. glycines at 60 days differed significantly from the control in the Clariva, Vitazyme and A19824 + Avicta 500 FS + Vitazyme treatments. For both analyzed variables, the evaluation at 30 days after inoculation was shown to be early and at 90 days the treatment action discontinuity observed at 60 days was observed. It was concluded that Clariva, Vitazyme, Clariva + Vitazyme and Clariva + Vitazyme + Avicta 500 FS reduced the number of nematode cysts, but there was no continuation of reduction after 60 days of inoculation.