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Populations of Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) with high frequencies and high levels of resistance to phosphine (PH 3 ), as detected by the Food and Agriculture Organization (FAO) discriminating dose test, were submitted to various concentrations of phosphine in air and to various concentrations of phosphine plus 10% and 20% carbon dioxide (CO 2 ) for 20 h. Three resistant populations and one susceptible population of each species were tested. Concentration-mortality regression lines to obtain the LC 50 and LC 99.9 values were determined for each population. The resistance levels for these mortality rates were also obtained. The mixtures of phosphine plus 10% and 20% CO 2 reduced the resistance levels of the S. oryzae populations. The more susceptible portion of the R. dominica population showed a decrease in the required phosphine concentration with an increase in CO 2 , but phosphine alone seemed to be more effective than the mixtures with CO 2 for the control of the more resistant portion. The mixtures of phosphine plus CO 2 reduced the resistance levels to phosphine in populations of R. dominica and S. oryzae , although a clear pattern could not be determined. Resistant populations of R. dominica and S. oryzae to phosphine showed different mortality responses to treatments with mixtures of phosphine plus 10% and 20% CO 2 .

Refined soybean and crude castor oils were evaluated for the control of infestations of Callosobruchus maculatus (F.) and Callosobruchus phaseoli (Gyllenhal) in stored chick-pea (Cicer arietinum L.). Both oils were used at 0,5 and 10 ml/kg of seeds. Oviposition, adult emergence and development from egg to adult emergence were evaluated after storing the treated seeds for up to 5 months. At the end of the storage period the effect of the treatments on flavour, consumer acceptability and seed germination were evaluated. Both oils inhibited population growth of the two insect species as compared to untreated seeds. Castor oil was more effective than soybean oil. Castor oil at 5 and 10 ml/kg protected stored chick-peas from infestation by C. maculatus for 60 and 150 d, and from infestation by C. phaseoli for 60 and 90 d, respectively. Soybean oil was not an effective protectant, but did reduce the C. maculatus and C. phaseoli population development for approximately 60 d at 5 ml/kg and for 90 d at 10 ml/kg. No harmful effect was observed on the germination of oil-treated seeds. The oil treatments conferred off-flavours to the chick-peas, and product acceptability was compromised by treatment with castor oil and soybean oil at 10 ml/kg.

O presente trabalho teve por objetivos: (a) verificar possíveis diferenças entre seis genótipos de grão-de-bico (Cicer arietinum L.), selecionados no Instituto Agronômico, quanto à suscetibilidade ao ataque de Callosobruchus phaseoli (Gyllenhal), C. maculatus F. e Acanthoscelides obtectus (Say), pragas de armazenamento dessa fabácea; (b) relacionar as diferenças em suscetibilidade com a composição química das sementes, e (c) avaliar a qualidade de cozimento das sementes dos genótipos com características agronômicas mais promissoras para o cultivo. Foram utilizadas sementes do cv. IAC-Marrocos e dos genótipos IAC-Sonora, IAC-Sonora-FE, IAC-GB2, IAC-GB3 e IAC-GB4 de grão-de-bico, as quais foram infestadas separadamente com as três principais espécies de insetos, obtendo-se o número de ovos por fêmea (Callosobruchus), a percentagem de ovos que se desenvolveram até adulto, o período de desenvolvimento de ovo a adulto e a perda de peso das sementes por inseto desenvolvido, parâmetros utilizados para avaliação dos genótipos, cuja composição em ácidos graxos foi determinada, procurando-se relacionar as diferenças obtidas com as diferenças em suscetibilidade. Verificaram-se diferenças de resistência ao ataque de bruquídeos entre os genótipos estudados. O IAC-GB2 foi o menos favorável ao desenvolvimento de C. maculatus, C. phaseoli e A. obtectus. A resistência de grão-de-bico a bruquídeos pode estar relacionada com componentes do tegumento que conferem coloração mais escura e/ou com a composição em ácido linoléico, influindo na oviposição e na alimentação e/ou biologia das larvas. Foi observada diferença na qualidade de cozimento entre os genótipos estudados. O IAC-Sonora apresentou qualidade de cozimento significativamente superior ao IAC-GB2.The bruchids have been observed as the most important species in chickpea (Cicer arietinum L.) storage. Nevertheless, many authors reported in some genotypes of Fabacea differences in susceptibility to bruchids attack, suggesting the use of resistant cultivars as a method to avoid infestation during storage. The Instituto Agronômico of Campinas (IAC), State of São Paulo, Brazil, has been selecting chickpeas genotypes suitable to local conditions. The main objective of this research was to verify the occurrence of resistance to Callosobruchus phaseoli (Gyllenhal), C. maculatus F. and Acanthoscelides obtectus (Say) in six chickpeas genotypes during storage. The genotypes were: cv. IAC-Marrocos, IAC-Sonora, IAC Sonora-FE, IAC-GB2, IAC-GB3 and IAC-GB4. Each of them was infested by insects of the three main species. The differences in resistance were evaluated by: (a) the percentage of eggs developed until adult phase, (b) period from egg to adult, (c) loss of weight in seeds per insect developed and (d) the number of eggs per female, the last one was applied only for Callosobruchus species. The seeds chemical composition, fat acids, was evaluated in order to establish a relationship with the seeds resistance or susceptibility. The cultivars IAC-Marrocos and IAC-GB2 showed evidences of resistance to bruchids. IAC-Sonora and IAC-Sonora-FE, which have the best agricultural characteristics, had their seeds cooking quality analyzed. Differences in bruchids attack were observed among the six chickpeas genotypes. IAC-GB2 was the less susceptible to C. maculatus, C. phaseoli and A. obtectus. The resistance to bruchids in chickpea may be related to tegument components as pigments, in dark tegument genotypes, and to the presence of linoleic acid, affecting oviposition and also larval feeding and/or larval biology. Cooking quality differed among genotypes. Cooking quality of IAC-Sonora was significatively higher than that of IAC-GB2.

O presente trabalho teve por objetivos: (a) verificar possíveis diferenças entre seis genótipos de grão-de-bico (Cicer arietinum L.), selecionados no Instituto Agronômico, quanto à suscetibilidade ao ataque de Callosobruchus phaseoli (Gyllenhal), C. maculatus F. e Acanthoscelides obtectus (Say), pragas de armazenamento dessa fabácea; (b) relacionar as diferenças em suscetibilidade com a composição química das sementes, e (c) avaliar a qualidade de cozimento das sementes dos genótipos com características agronômicas mais promissoras para o cultivo. Foram utilizadas sementes do cv. IAC-Marrocos e dos genótipos IAC-Sonora, IAC-Sonora-FE, IAC-GB2, IAC-GB3 e IAC-GB4 de grão-de-bico, as quais foram infestadas separadamente com as três principais espécies de insetos, obtendo-se o número de ovos por fêmea (Callosobruchus), a percentagem de ovos que se desenvolveram até adulto, o período de desenvolvimento de ovo a adulto e a perda de peso das sementes por inseto desenvolvido, parâmetros utilizados para avaliação dos genótipos, cuja composição em ácidos graxos foi determinada, procurando-se relacionar as diferenças obtidas com as diferenças em suscetibilidade. Verificaram-se diferenças de resistência ao ataque de bruquídeos entre os genótipos estudados. O IAC-GB2 foi o menos favorável ao desenvolvimento de C. maculatus, C. phaseoli e A. obtectus. A resistência de grão-de-bico a bruquídeos pode estar relacionada com componentes do tegumento que conferem coloração mais escura e/ou com a composição em ácido linoléico, influindo na oviposição e na alimentação e/ou biologia das larvas. Foi observada diferença na qualidade de cozimento entre os genótipos estudados. O IAC-Sonora apresentou qualidade de cozimento significativamente superior ao IAC-GB2. The bruchids have been observed as the most important species in chickpea (Cicer arietinum L.) storage. Nevertheless, many authors reported in some genotypes of Fabacea differences in susceptibility to bruchids attack, suggesting the use of resistant cultivars as a method to avoid infestation during storage. The Instituto Agronômico of Campinas (IAC), State of São Paulo, Brazil, has been selecting chickpeas genotypes suitable to local conditions. The main objective of this research was to verify the occurrence of resistance to Callosobruchus phaseoli (Gyllenhal), C. maculatus F. and Acanthoscelides obtectus (Say) in six chickpeas genotypes during storage. The genotypes were: cv. IAC-Marrocos, IAC-Sonora, IAC Sonora-FE, IAC-GB2, IAC-GB3 and IAC-GB4. Each of them was infested by insects of the three main species. The differences in resistance were evaluated by: (a) the percentage of eggs developed until adult phase, (b) period from egg to adult, (c) loss of weight in seeds per insect developed and (d) the number of eggs per female, the last one was applied only for Callosobruchus species. The seeds chemical composition, fat acids, was evaluated in order to establish a relationship with the seeds resistance or susceptibility. The cultivars IAC-Marrocos and IAC-GB2 showed evidences of resistance to bruchids. IAC-Sonora and IAC-Sonora-FE, which have the best agricultural characteristics, had their seeds cooking quality analyzed. Differences in bruchids attack were observed among the six chickpeas genotypes. IAC-GB2 was the less susceptible to C. maculatus, C. phaseoli and A. obtectus. The resistance to bruchids in chickpea may be related to tegument components as pigments, in dark tegument genotypes, and to the presence of linoleic acid, affecting oviposition and also larval feeding and/or larval biology. Cooking quality differed among genotypes. Cooking quality of IAC-Sonora was significatively higher than that of IAC-GB2.