Selectivity of neem to Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis (Hymenoptera: Trichogrammatidae)

Abstract

-Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis are commonly found in avocado and persimmon orchards in northern Parana state. However, their abundance depends on whether insecticides are used or not to control the key lepidopteran pests Stenoma catenifer (Wals.) (Lepidoptera: Elachistidae) and Hypocala andremona (Stoll) (Lepidoptera: Noctuidae), respectively. The aim of this work was to evaluate the effects of an aqueous neem seed extract (ANSE) at 15, 3 and 1.5%, and of an emulsifi able concentrate neem oil (ECNO) at 2.5, 0.5 and 0.25% on lifetime parameters of these trichogrammatids as a way of testing the feasibility of integrating the biological and chemical control methods. Chemicals were applied on Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs before or after parasitization (one, three or fi ve days). ANSE was more deleterious to both parasitoid species than ECNO, regardless of the concentration and the time of application. The chemicals acted on a concentration and time dependent manner. Treating the host with neem before parasitism was less deleterious to wasp emergence, especially for T. annulata. Pre-treatments (24h) of the host eggs with ECNO at concentrations varying from 0.5% to 0.25% did not affect T. pretiosum longevity, but 2.5% reduced T. annulata survival. Feeding wasps with honey mixed with 0.25% ECNO negatively affected T. annulata survival.

Physiological Effects of Resveratrol and Coumaric Acid on Two Major Groundnut Pests and Their Egg Parasitoid Behavior

“…Some plant volatile organic compounds and hydrocarbons act as semiochemicals in host selection and host recognition by T. chilonis (Dicke et al., ; Hoballah and Turlings, ; Romies et al., ; Sen et al., ). Various plant‐generated volatile compounds may act in indirect host plant defense, serving as efficient cues to T. chilonis (Hohmann et al., ; Xavier et al., ; Usha Rani and Sandhyarani, ). This supports the concept that plant chemicals produced due to biotic stress can attract parasitoids.…”

Seletividade de produtos naturais comerciais a Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae)

“…A variação observada nos resultados dos diferentes trabalhos com azadiractina pode estar relacionada com o tipo de produto ou sua formulação, pois o óleo pode ter provocado redução do número de ovos parasitados, por apresentar maior concentração desse princípio ativo (Menezes, 2005;Hohmann et al, 2010). O produto Topneem ® , testado neste trabalho, apresenta em sua composição os princípios ativos rotenona (Derris sp.…”

“…Trabalhos têm sido desenvolvidos para avaliar o efeito de produtos conhecidos como alternativos, botânicos ou naturais, sobre Trichograma pretiosum Riley (Hymenoptera: Trichogrammatidae), com extratos aquosos e outros produtos à base de neem (Azadirachta in-dica A. Juss) (Oliveira et al, 2003;Gonçalves-Gervásio & Vendramim, 2004, Hohmann et al, 2010Silva, 2010), extrato pirolenhoso (Morandi Filho et al, 2006, Silva, 2010, extratos de asteráceas (Tavares et al, 2009), óleo de mamona (Bestete et al, 2011), extratos de mirtáceas (Purwatiningsih et al, 2012) e produtos botânicos comerciais (Silva, 2010).…”

Ecosmart Biorational Insecticides: Alternative Insect Control Strategies

“…Ecologically, azadirachtin is non toxic to fish (Wan et al, 1996), natural enemies and pollinators (Naumann & Isman, 1996), birds, other wild life, and aquatic organisms as azadirachtin, breaks down in water within 50-100 h. It is harmless to non-target insects (bees, spiders, and butterflies). The effect of azadirachtin on natural enemies is highly variable (Hohmann et al, 2010, Kumar et al, 2010. Environmentally, azadirachtin induce no accumulations in the soil, no phytotoxicity and accumulation seen in plants, and no adverse effect on water or groundwater (Mehlhorn, 2011).…”

“…Ecto-endo parasitoids vulnerable to neem but soil application could reduce negative side effects compared to plant spraying and hence improve selectivity (Kumar et al, 2010). Treating the host with neem before parasitism was less deleterious to wasp emergence, especially for Trichogrammatoidea annulata (Hohmann et al, 2010). For more details about safety of neem, see Boeke et al (2004), Mehlhorn (2011), Kumar et al (2010), andHomanni et al (2010).…”