Abstract

SANCHEZ-SAAVEDRA, María Guadalupe; CORTEZ-MADRIGAL, Hipólito  and  CRISTOBAL-ACEVEDO, David. Infectivity of Heterorhabditis indica (Rhabditida: Heterorhabditidae) in adults and larvae of white grub (Coleoptera: Melolonthidae). Rev. Chapingo Ser.Hortic [online]. 2012, vol.18, n.3, pp.383-394. ISSN 2007-4034.  https://doi.org/10.5154/r.rchsh.2012.08.040.

To determine the potential of the nematode Heterorhabditis indica in the management of the white grub complex (Col: Melolonthidae), during 2010 and 2011 bioassays were implemented with larvae and adults of the pest in Jiquilpan, Michoacán, Mexico. The insects were collected in the study region; the first, in corn, and the latter, in light traps, where the genus Phyllophaga dominated. A dose of 2,500 nematodes·ml^-1 per individual was applied and the mortality readings began at 24 h. To determine mortality, an analysis of variance was employed. The time in which 50 % of the population died (LT50) was estimated by means of probit analysis. The infectivity of the nematode was estimated through larvae of Gallería mellonella in three regional soils. In addition, correlation tests were practiced to know the relationship between the soil characteristics and mortality. Five days later, the mortality of third stage larvae was 46 %. For adults, the LT50 was estimated at 48.97 h (47-49 - 51.34 h). No infective juveniles emerged from any of the adults killed by H. indica. The texture, pH and EC were the soil characteristics that influenced most in the activity of the nematode. Results show that H. indica has potential for the management of larvae and adults of Phyllophaga spp. The technique of self-dissemination of the nematode is proposed using adults of white grub. However, first it is necessary to identify the cause that limited the emergence of juvenile nematodes from adults of the pest.

Keywords : Phyllophaga spp; nematodes; mortality; larvae; adults.