Efeitos Sinérgicos de Combinações entre Nematóides Entomopatogênicos (Nemata: Rhabditida) e Inseticidas Químicos na Mortalidade de Sphenophorus levis (Vaurie) (Coleoptera: Curculionidae)

Abstract

-The effect of combinations of the entomopathogenic nematodes Heterorhabditis indica Poinar, Karunakar & David, 1992 (strain IBCB-n5) and Steinernema sp. (strain IBCB-n6) at doses of 2.4;12 and 60 IJ/cm 2 , with sub-doses of the chemical insecticides fipronil, thiamethoxam and imidacloprid were tested in laboratory conditions against adults and larvae of the sugarcane billbug, Sphenophorus levis Vaurie, 1978. Firstly, the effect of fipronil (200 g A.I./ha), thiamethoxam (250 g A.I./ha) and imidacloprid (700 g A.I./ha) were evaluated on the nematode viability. The insecticides were compatible with the nematodes, not affecting the viability of the infective juvenile after 24 hours. For the experiments with adults, the treatments containing nematodes and insecticides tested separately showed mortality below 25%, except for the two highest doses of Steinernema sp. (at 12 and 60 IJ/cm 2 ), with mortality levels of 33.3% and 50% respectively. For the mixtures of the nematodes with sub-doses of thiamethoxam (62.5 g A.I./ha), the mortality levels increased significantly, reaching up to 66.7%, with the mixture of H. indica at 60 IJ/cm 2 , and 70% to 83.3% at all doses of Steinernema sp., showing synergistic effect at these combinations. The combination of H. indica and Steinernema sp. (12 IJ/cm 2 ) with thiamethoxam (62.5 g A.I./ha) against larva, the nematodes tested alone or in mixture with the insecticides showed mortality levels between 75% and 87.5%, indicating no advantage of the mixture for improving the insect mortality.KEYWORDS -integrated pest management, Heterorhabditis indica, Steinernema sp., sugarcane billbug, microbial control. RESUMO -Foi testado em laboratório, o efeito de combinações dos nematóides entomopatogênicos

Compatibility of Entomopathogenic Nematodes with Chemical Insecticides for the Control of Drosophila suzukii (Diptera: Drosophilidae)

“…[ 15 ]. On the other hand, lambda-cyhalothrin affected the viability of S. carpocapsae and S. amazonensis in this study, which corroborates Negrisoli Jr. et al’s [ 16 ] study with S. carpocapsae and S. glaseri (Steiner).…”

Performance of entomopathogenic nematodes on the mealybug, Dysmicoccus brevipes (Hemiptera: Pseudococcidae) and the compatibility of control agents with nematodes

“… Tavares et al (2009) performed a compatibility test of H. Indica and Steinernema sp., using fipronil, thiamethoxam, and imidacloprid, confirming the compatibility of these biological agents with these insecticides. In a laboratory test, the mortality of EPNs ranged from 0.7 to 3% when exposed to imidacloprid.…”

Compatibility between entomopathogenic nematodes and crop protection products used in maize seed treatment

“…Such a difference may be because the IOBC protocol takes into account all the analyzed parameters for the classification of products (E%) ( Table 2). Tavares et al (2009) exposed the nematodes H. indica IBCBn5 and Steinernema brasilense IBCBn6 to thiamethoxam, which is the active ingredient in Cruiser 350 FS ® , and demonstrated the compatibility of both nematodes with the insecticide. Other studies have already reported the compatibility of thiamethoxam with other nematode species, e.g., H.…”