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Reduviidae (Hemiptera) is a family of polyphagous predators that can be used as biological control agents for one or more pest species. Predator efficiency of Pselliopus latispina over Tetranychus urticae Koch females was evaluated using the functional response at different mite densities. Mites were exposed to predation in Petri dishes under laboratory controlled conditions during 24 hours. Predators consumed an average of 56.3 individuals of 64 adult females of T. urticae, with a type II functional response according to Holling's instant discovery rate model (a') of 1.0597, and a handling time (th) of 0.00442. These results indicated that Pselliopus latispina is a predator with broad perspective that can be used in different crops. [ABSTRACT FROM AUTHOR]

The functional response of the third instar larvae of Chrysoperla carnea (Stephens) on densities of Trialeurodes vaporariorum (Westwood) eggs was evaluated under controlled conditions. A functional type II response (Holling's disk) was observed. Holling and Livdahl & Stiven models gave similar values for estimating parameters of the Holling's disk equation; however, estimates produced by the Rogers were higher. According to the results obtained of predation, C. carnea has considerable potential for the control of T. vaporariorum. [ABSTRACT FROM AUTHOR]

The objective of this research was to compare the toxicity of reduced doses and enzymatic activity associated with insecticide tolerance to abamectin and profenofos on Chrysoperla carnea Stephens and its prey Bactericera cockerelli Sulc. Residual toxicity was measured at 0.1, 0.5, and 1.0% of the recommended dose of abamectin and profenofos for controlling B. cockerelli. Measured were α-esterases, β-esterases, glutathione S-transferases (GSTs), and oxidase content of larvae and nymphs of C. carnea and B. cockerelli exposed to the insecticides. The three abamectin concentrations killed more nymphs of the pest than did larvae of green lacewing. Profenofos at 1.0% concentration was very toxic to the pest and its predator. At concentrations of 0.5 and 1.0, fewer died and was similar for both species. Abamectin killed fewer C. carnea than did profenofos at the three doses. Enzymatic activity of α and β-esterase was greater for C. carnea compared with B. cockerelli exposed to abamectin and profenofos. Activity of the enzyme glutathione S-transferases (GSTs) and oxidase content where greater for B. cockerelli than C. carnea. The study demonstrated that abamectin was less toxic to C. carnea and more to B. cockerelli, suggesting the insecticide was very selective, which could be related to greater esterase enzymatic activity. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) plants have developed or adapted over time efficient defense mechanisms against insect attack. Because the mechanisms often fail to be effective enough, alternatives are needed to help counteract attacks by pests. Sodium menadione bisulfite (MBS), a compound derived from vitamin K3, possesses insecticidal properties. In this work, bioassays were done to verify insecticidal effect of MBS on Bactericera cockerelli (Sulc) and Bemisia tabaci (Gennadius). MBS killed more than 80 and 60% of the insects evaluated, with LC50 of 54.79 and 521.72 ppm, respectively. MBS also deformed B. cockerelli adults hatched from nymphs exposed to concentrations of MBS tested under in vitro conditions. Therefore, menadione can be considered an alternative for integrated management of B. cockerelli and B. tabaci. [ABSTRACT FROM AUTHOR]