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

Abstract

The performance of nine isolates of Heterorhabditis amazonensis and one of Heterorhabditis indica on the mealybug Dysmicoccus brevipes, (Hemiptera: Pseudococcidae), were evaluated. The most virulent isolates were evaluated for nematode vertical and horizontal dispersal, and for efficiency at concentrations of 0 (control), 25, 50, 75, and 100 infective juveniles (IJs)/cm 2 on adult females of the insect. A compatibility assessment was also carried out with commercial products, registered or in the process of registration, for use in the cassava culture. The isolates that caused the highest mortality rate of D. brevipes were NEPET11 (93.8% ± 4.1) and IBCB-n40 (84.0% ± 8.1), both isolates of Heterorhabditis amazonensis, while the isolate NEPET11 was more virulent than IBCB-n40 at all concentrations evaluated. In the dispersal test, the NEPET11 isolate caused mortality in the mealybug at a depth of up to 20 cm and a horizontal displacement of 7.25 cm. In the compatibility test, the NEPET11 isolate exhibited reduced viability due to the products Poquer, Tiguer 100 EC, Actara 250 WG, and Gaucho FS. The insecticide Curyom 550 EC was the only one that reduced infectivity (reduction of 92%) and is the only product classified as moderately toxic, while all the others were classified as compatible based on E%.

Assessment of entomopathogenic nematodes and their symbiotic bacteria to control the stink bugs Euschistus heros and Dichelops melacanthus (Heteroptera: Pentatomidae) in the soybean-corn succession system

“…There have been some reports of EPNs serving as biological control agents against Hemiptera species on the leaves (Martínez-Córdoba et al, 2011;Naranjo et al, 2013;Niekerk and Malan, 2013;Platt et al, 2020), trunks/stems/shoots (Shapiro-Ilan and Mizell, 2012;Marrero et al, 2015;Guide et al, 2015;Guide et al, 2019) and soil (Leite et al, 2005;Melo et al 2006;Batista and Auad, 2010;Vieux and Malan, 2013;Mbata and Shapiro-Ilan, 2013;Batista et al, 2014;Alves et al, 2009;Guerrero & Pardey, 2019;Moussa et al, 2021;Zart et al, 2021). Susceptibilities of these insects range widely, with some species being more resistant than other usually tested insect hosts, requiring high rate of EPNs (100 IJs/cm 2 ) to provide > 70% mortality (Guide et al, 2015;Guide et al, 2019).…”

Virulence of entomopathogenic nematodes and their symbiotic bacteria, under laboratory conditions, aiming controlling Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae) on sugarcane

“…infective juvenile (IJ) digestive system killing the host by septicemia (Poinar Junior and Grewal, 2012). The high susceptibility of the pseudococcids Dysmicoccus brevipes (Cockerell, 1893) (Hemiptera: Pseudococcidae) (Zart et al, 2021) and Dysmicoccus texensis (Tinsley, 1900) (Hemiptera: Pseudococcidae) (Alves et al, 2009) to EPNs suggests the pink sugarcane mealybug could be a potential target.…”