Seed Treatment with Bacillus amyloliquefaciens for the control of Meloidogyne javanica “in vivo” bean culture and its direct effect on the motility, mortality and hatching of M. javanica “in vitro”

Abstract

The gill nematode (Meloidogyne spp.) is a widely distributed phytoparasite capable of causing great yield losses in the most diverse cultures. Therefore, the objective of the present work is to evaluate the effect of Bacillus amyloliquefaciens used in the treatment of seeds as a biocontrol agent of Meloidogyne javanica in common bean, and the direct effect of M. javanica on hatching, motility and in vitro mortality. Experiments were conducted in the municipality of Cascavel, Paraná, in a greenhouse and laboratory. A randomized complete block design (DBC) was used, using five different doses of the biocontrol (0, 50, 100, 150 and 200% of the recommended dose), with five replicates for both experiments. The sowing of 3 seeds of cv. IPR Bullfinch was performed in 2 L plastic vessels with autoclaved soil and sand mix. The inoculation of 2000 eggs / J2 of M. javanica per plant was carried out in a sequence. Forty days after inoculation, the plants were removed for evaluation, where vegetative parameters and nematological parameters were analyzed. In the laboratory bacterial / nematological suspensions were added totaling 10mL per plate. Hatching in distilled water was used as control. The chambers were maintained in B.O.D. to 27 +/- 1º C with photoperiod of 12 hours / light. Hatching, motility and mortality were evaluated at 9 and 15 days. Both data were subjected to a regression analysis at 5% probability level, using the statistical software SISVAR, version 5.6. Results showed that the bacterial isolate B. amyloliquefaciens is a potential controller of M. javanica "in vitro", as well as of “in vivo" vegetative and nematological parameters.