Resistance of Soybean Genotypes to Anticarsia gemmatalis (Lepidoptera: Erebidae): Antixenosis and Antibiosis Characterization.

Injury by herbivores is a major biotic stress that limits soybean [Glycine max (L.) Merrill] crop production. Among the main soybean insect pests, Anticarsia gemmatalis Hübner is responsible for causing significant economic damage in soybean. The primary management strategy for this insect is chemical control and use of Bt transgenic soybean. Alternative strategies, such as host plant resistance, are considered an efficient and less-aggressive method, especially in association with other strategies as part of an integrated pest management (IPM) approach. In this study, we evaluated 30 soybean genotypes to verify antixenosis expression through oviposition, attractiveness, and food consumption tests. From this, we selected 13 promising genotypes to verify the possible presence of antibiosis. Our results suggest that antixenosis was found in genotypes 'TMG 133' RR, 'TMG 1179' RR, 'IAC 19', 'IAC 17', 'IAC 100', D75-10169, and IAC 78-2318. By influence on behavior and negative impact on larval viability, antixenosis and antibiosis were indicated for the genotypes IAC 74-2832, 'IAC 19', 'IAC 17', 'IAC 100', and PI 274454. 'TMG 7062' IPRO was found to provide antibiosis resistance by negatively affecting larval development and viability. Because of reduced food consumption by larvae, antixenosis was indicated for 'IAC 24'. These genotypes should be considered in soybean breeding programs focusing on soybean resistance to A. gemmatalis.

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae) / Influência da dieta do hospedeiro na performance de Doryctobracon areolatus (Hymenoptera: Braconidae)

Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.(AU)

O custo adaptativo de parasitoides é geralmente influenciado pela qualidade do hospedeiro. Nós avaliamos parâmetros de desenvolvimento do parasitoide Doryctobracon areolatus (Hymenoptera: Braconidae) em larvas de Anastrepha fraterculus (Diptera: Tephritidae) criadas em dieta artificial com diferentes fontes proteicas. Larvas de A. fraterculus foram criadas em dietas a base de: 1) germe de trigo cru (testemunha); 2) farinha de arroz integral; 3) farinha de milho; e, 4) farinha de trigo integral + farelo de soja. As larvas foram usadas para o desenvolvimento de D. areolatus para avaliar o número de descendentes/fêmea, taxa de emergência, razão sexual, duração do período ovo-adulto, peso de adultos, comprimento da tíbia posterior e longevidade. Larvas de A. fraterculus criadas nas dietas a base de germe de trigo e farinha de milho, permitiram obter um maior número de descendentes do parasitoide, com menor duração do período de desenvolvimento ovo-adulto, para ambos os sexos. Nas dietas com farinha de arroz e farinha de milho, larvas de A. fraterculus geraram adultos de D. areolatus com maior peso e tamanho de tíbia de machos e fêmeas e uma maior quantidade de fêmeas. A dieta contendo farinha de trigo + farelo de soja afetou a geração de descendentes, causando uma menor razão sexual. As dietas a base de farinha de arroz e milho são as mais adequadas para a multiplicação do parasitoide.(AU)

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae) / Influência da dieta do hospedeiro na performance de Doryctobracon areolatus (Hymenoptera: Braconidae)

Abstract Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.

Resumo O custo adaptativo de parasitoides é geralmente influenciado pela qualidade do hospedeiro. Nós avaliamos parâmetros de desenvolvimento do parasitoide Doryctobracon areolatus (Hymenoptera: Braconidae) em larvas de Anastrepha fraterculus (Diptera: Tephritidae) criadas em dieta artificial com diferentes fontes proteicas. Larvas de A. fraterculus foram criadas em dietas a base de: 1) germe de trigo cru (testemunha); 2) farinha de arroz integral; 3) farinha de milho; e, 4) farinha de trigo integral + farelo de soja. As larvas foram usadas para o desenvolvimento de D. areolatus para avaliar o número de descendentes/fêmea, taxa de emergência, razão sexual, duração do período ovo-adulto, peso de adultos, comprimento da tíbia posterior e longevidade. Larvas de A. fraterculus criadas nas dietas a base de germe de trigo e farinha de milho, permitiram obter um maior número de descendentes do parasitoide, com menor duração do período de desenvolvimento ovo-adulto, para ambos os sexos. Nas dietas com farinha de arroz e farinha de milho, larvas de A. fraterculus geraram adultos de D. areolatus com maior peso e tamanho de tíbia de machos e fêmeas e uma maior quantidade de fêmeas. A dieta contendo farinha de trigo + farelo de soja afetou a geração de descendentes, causando uma menor razão sexual. As dietas a base de farinha de arroz e milho são as mais adequadas para a multiplicação do parasitoide.

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae).

Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae)

Abstract Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.

Resumo O custo adaptativo de parasitoides é geralmente influenciado pela qualidade do hospedeiro. Nós avaliamos parâmetros de desenvolvimento do parasitoide Doryctobracon areolatus (Hymenoptera: Braconidae) em larvas de Anastrepha fraterculus (Diptera: Tephritidae) criadas em dieta artificial com diferentes fontes proteicas. Larvas de A. fraterculus foram criadas em dietas a base de: 1) germe de trigo cru (testemunha); 2) farinha de arroz integral; 3) farinha de milho; e, 4) farinha de trigo integral + farelo de soja. As larvas foram usadas para o desenvolvimento de D. areolatus para avaliar o número de descendentes/fêmea, taxa de emergência, razão sexual, duração do período ovo-adulto, peso de adultos, comprimento da tíbia posterior e longevidade. Larvas de A. fraterculus criadas nas dietas a base de germe de trigo e farinha de milho, permitiram obter um maior número de descendentes do parasitoide, com menor duração do período de desenvolvimento ovo-adulto, para ambos os sexos. Nas dietas com farinha de arroz e farinha de milho, larvas de A. fraterculus geraram adultos de D. areolatus com maior peso e tamanho de tíbia de machos e fêmeas e uma maior quantidade de fêmeas. A dieta contendo farinha de trigo + farelo de soja afetou a geração de descendentes, causando uma menor razão sexual. As dietas a base de farinha de arroz e milho são as mais adequadas para a multiplicação do parasitoide.

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae)

Abstract Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.

Resumo O custo adaptativo de parasitoides é geralmente influenciado pela qualidade do hospedeiro. Nós avaliamos parâmetros de desenvolvimento do parasitoide Doryctobracon areolatus (Hymenoptera: Braconidae) em larvas de Anastrepha fraterculus (Diptera: Tephritidae) criadas em dieta artificial com diferentes fontes proteicas. Larvas de A. fraterculus foram criadas em dietas a base de: 1) germe de trigo cru (testemunha); 2) farinha de arroz integral; 3) farinha de milho; e, 4) farinha de trigo integral + farelo de soja. As larvas foram usadas para o desenvolvimento de D. areolatus para avaliar o número de descendentes/fêmea, taxa de emergência, razão sexual, duração do período ovo-adulto, peso de adultos, comprimento da tíbia posterior e longevidade. Larvas de A. fraterculus criadas nas dietas a base de germe de trigo e farinha de milho, permitiram obter um maior número de descendentes do parasitoide, com menor duração do período de desenvolvimento ovo-adulto, para ambos os sexos. Nas dietas com farinha de arroz e farinha de milho, larvas de A. fraterculus geraram adultos de D. areolatus com maior peso e tamanho de tíbia de machos e fêmeas e uma maior quantidade de fêmeas. A dieta contendo farinha de trigo + farelo de soja afetou a geração de descendentes, causando uma menor razão sexual. As dietas a base de farinha de arroz e milho são as mais adequadas para a multiplicação do parasitoide.