Efeito do aldicarbe no ciclo de vida de Meloidogyne incognita

Abstract

Eggs, juveniles of the second stage (J2) and females of Meloidogyne incognita were placed in solution of the nematicide aldicarb. Exposure to nematicide caused: (1) reduction in hatching, (2) mobility and (3) J2 mortality, and (4) reduction in penetration. The application of nematicide after infection with healthy J2 was more efficient in reducing nematode reproduction. The application made closer to J2 inoculation caused greater galls and eggs/g of soybean root reductions with larger effect on reproduction. Whereas the 24 h stored J2 in aldicarb 50 μg mL-1 and inoculated in soybean had the number of eggs/g of root reduced at 2.5% compared to control, the application of the same aldicarb concentration after inoculation resulted on 95% reduction. The irrigation of the substrate with aldicarb solution impeded J2 penetration and interrupted the life cycle. The amount of J2 lipid body energy was assessed by staining with “Oil Red O” and photos analyzed by image program. The body energy was alike on J2 stored in aldicarb and in pure water at 25 ºC up to eight days. Therefore, the aldicarb affect, accumulatively, over various phases of M. incognita life cycle with greater effect on reproduction and J2 disorientation towards soybean roots, without preserving body energy in aldicarb stored J2.