Interação de proteínas Cry1 e Vip3A de Bacillus thuringiensis para controle de lepidópteros-praga

Abstract

Resumo -O objetivo deste trabalho foi avaliar a suscetibilidade das lagartas Anticarsia gemmatalis (Lepidoptera: Erebidae) e Chrysodeixis includens (Lepidoptera: Noctuidae) às proteínas Cry1 e Vip3A, bem como determinar se há a interação entre essas proteínas no controle das duas espécies. Bioensaios com as proteínas isoladas e em combinações foram realizados, e as concentrações letais CL 50 e CL 90 foram estimadas para cada condição. As proteínas Cry1Aa, Cry1Ac e Vip3Af foram as mais efetivas no controle de A. gemmatalis, enquanto Cry1Ac, Vip3Aa e Vip3Af foram mais efetivas no de C. includens. As proteínas Cry1Ac e Cry1Ca causaram maior inibição do desenvolvimento das larvas sobreviventes à CL 50 , em ambas as espécies. Combinações entre Vip3A e Cry1 apresentam efeito sinérgico no controle das espécies e a combinação Vip3Aa+Cry1Ea destaca-se no controle de A. gemmatalis e C. includens. Essas proteínas combinadas são promissoras na construção de plantas piramidadas, para o controle simultâneo das pragas.Termos para indexação: Anticarsia gemmatalis, Chrysodeixis includens, manejo da resistência, piramidação de genes, sinergismo, soja transgênica. Interaction of Cry1 and Vip3A proteins of Bacillus thuringiensis for the control of lepidopteran insect pestsAbstract -The objective of this work was to evaluate the susceptibility of Anticarsia gemmatalis (Lepidoptera: Erebidae) and Chrysodeixis includens (Lepidoptera: Noctuidae) caterpillars to Cry1 and Vip3A proteins, as well as to determine if there is any interaction between these proteins on the control of the two species. Bioassays with both isolated and combined proteins were carried out, and lethal concentrations LC 50 and LC 90 were estimated for each condition. Cry1Aa, Cry1Ac, and Vip3Af were the more effective proteins for the control of A. gemmatalis, while Cry1Ac, Vip3Aa, and Vip3Af were more effective for the control of C. includens. Cry1Ac and Cry1Ca proteins caused the highest inhibition to the development of larvae that survived the LC 50 dose in both species. Different combinations of Vip3A and Cry1 have synergistic effect in the control of both species, and the combination Vip3Aa + Cry1Ea showed an outstanding control of A. gemmatalis and C. includens. These proteins are promising for building pyramided plants for the simultaneous control of the pests.

Toxicity and Binding Studies of Bacillus thuringiensis Cry1Ac, Cry1F, Cry1C, and Cry2A Proteins in the Soybean Pests Anticarsia gemmatalis and Chrysodeixis (Pseudoplusia) includens

“…includens (Table 1). These results are in agreement with previous studies performed using diet surface overlay (26) and by diet incorporation (9, 27, 28). In all cases, the LC 50 s obtained showed that A.…”

“…includens than to A. gemmatalis, similar to findings reported by Crialesi-Legori et al for Cry1Ca (26), who reported LC 50 values for Cry1Ca slightly higher than the ones obtained in this study. On the other hand, it has been described that Cry2A was either nontoxic to A.…”

Cry1Ac and Vip3Aa proteins fromBacillus thuringiensistargeting Cry toxin resistance inDiatraea flavipennellaandElasmopalpus lignosellusfrom sugarcane

“…Baranek et al (2015) analyzed the toxicity of Vip3 proteins (Vip3Aa58 and Vip3Aa59) and found efficacy in S. exigua (Hübner) (Lepidoptera: Noctuidae). More broadly, other studies have shown Vip proteins are efficient to control other species of lepidopteran pests (Crialesi-Legori et al, 2014; Lemes et al, 2014; Marucci et al, 2015). Recently, Vip3Aa has been introduced in prominent crops to increase protection against lepidopteran pests, and also as part of a basic strategy for resistance management as response to an emerging resistance to Cry proteins (Downes & Mahon, 2012; Tabashnik, Wu & Wu, 2012).…”

“…Mortality was recorded after 15 and 7 days for D. flavipennella and E. lignosellus , respectively. As control, we used distilled water, protein solubilization buffer and E. coli cell lysates (without host vector expression) with cry and vip3 genes, as performed by Crialesi-Legori et al (2014). LC 50 determination was by mortality counts for each protein and evaluated concentrations with Probit analysis (Finney, 1971) using Polo-Plus software (LeOra Software, Berkeley, CA, USA).…”

Produtividade E Retorno Economico Da Cultura Da Soja Com Tecnologia Intacta

“…2017 382 produtividade da cultura da soja destacam-se o ataque de insetos-praga, em especial da lagarta-da-soja (Anticarsia gemmatalis -Lepidoptera: Noctuidae), considerado o principal inseto desfolhador da cultura, podendo ocasionar grandes impacto na produtividade da mesma (LOURENÇÃO et al, 2010). Essa praga apresenta elevada ocorrência, com necessidade de controle frequente, considerando que o método mais utilizado é o químico ou com uso de plantas transgênicas resistentes (MORALES & SILVA, 2006;CRIALESI-LEGORI et al, 2014).…”