Nutritional aspects and larvae preference of Anticarsia gemmatalis Hüebner, 1818 (Lepidoptera: Noctuidae) on damaged and undamaged soybean cultivars | Aspectos nutricionais e preferência da lagarta-da-soja,Anticarsia gemmatalis Hüebner, 1818 (Lepidoptera: Noctuidae) em genótipos de soja com e sem injúria

English. Resistance to insects can be due to chemical factors present in the plant, and, according to the nature of the compounds, the resistance may be constitutive (independent of environmental stress), or induced by stress. In the case of soybeans, there are citations of constitutive and induced resistance, and for induced resistance, the value of information produced by the plant depends, for example, on the degree of the herbivore infestation. The induced resistance due to injury caused by the feeding of caterpillarsPseudoplusia includens in soybean occurs and has its peak near the 10th day after the injury. This way, the objective of this paper was to study the influence of previous injury in soybean genotypes, ‘Embrapa 4’ and ‘BR 37’, through the soybean defoliation by caterpillars, the preference and nutrition of Anticarsia gemmatalis. From the results obtained, it was possible to observe that the genotype ‘Embrapa 4’ is preferred by the caterpillars of A. gemmatalis in relation to ‘BR 37’, with a much higher leaf area consumed. As for the first one, an evident induction of resistance by a prior herbivory occurs, since the tests performed after defoliation show negative influence on insect development; consumption and use of food indexes were, in general, higher also for the variety ‘Embrapa 4’ which was not injured.

Portuguese. RESUMO – A resistência ao ataque de insetos decorre de fatores químicos presentes na planta, sendo que, conforme a natureza dos compostos, a resistência pode ser constitutiva (independente de estresse ambiental), ou induzida por estresse. No caso da soja existem citações de resistência constitutiva e induzida, sendo que nesta última o valor da informação emitida pela planta depende, por exemplo, do grau de infestação do herbívoro. A resistência induzida devido à injúria provocada pela alimentação de lagartas de Pseudoplusia includens em plantas de soja ocorre e tem o pico próximo ao 10º dia após a injúria, decaindo a partir de então. Assim, o objetivo deste trabalho foi estudar a influência da injúria prévia, nos genótipos ‘Embrapa 4’ e ‘BR 37’ de soja, por meio do desfolhamento por lagartas da soja, na preferência e na nutrição de A. gemmatalis. Pelos resultados obtidos, o genótipo ‘Embrapa 4’ é preferido pelas lagartas de A. gemmatalis em relação ao ‘BR 37’, sendo que para o primeiro ocorre evidente indução de resistência pela herbivoria prévia; os índices de consumo e utilização de alimento, de modo geral, foram mais elevados também para ‘Embrapa 4’ não injuriado. Nutritional aspects and larvae preference of Anticarsia gemmatalis Hüebner, 1818(Lepidoptera: Noctuidae) on damaged and undamaged soybean cultivarsAbstractResistance to insects can be due to chemical factors present in the plant, and, according to thenature of the compounds, the resistance may be constitutive (independent of environmentalstress), or induced by stress. In the case of soybeans, there are citations of constitutive and inducedresistance, and for induced resistance, the value of information produced by the plant depends, forexample, on the degree of the herbivore infestation. The induced resistance due to injury caused bythe feeding of caterpillars Pseudoplusia includens in soybean occurs and has its peak near the 10thday after the injury. This way, the objective of this paper was to study the influence of previous injuryin soybean genotypes, ‘Embrapa 4’ and ‘BR 37’, through the soybean defoliation by caterpillars,the preference and nutrition of Anticarsia gemmatalis. From the results obtained, it was possible toobserve that the genotype ‘Embrapa 4’ is preferred by the caterpillars of A. gemmatalis in relationto ‘BR 37’, with a much higher leaf area consumed. As for the first one, an evident induction ofresistance by a prior herbivory occurs, since the tests performed after defoliation show negativeinfluence on insect development; consumption and use of food indexes were, in general, higheralso for the variety ‘Embrapa 4’ which was not injured.