Comportement sexuel et stratégie reproductrice chez le Chryseida bennetti Burks (Hymenoptera: Eurytomidae), parasitoïde de la bruche du haricot. I. Effet de l'âge des partenaires

1994 ◽  
Vol 72 (1) ◽  
pp. 126-134 ◽  
Author(s):  
Gabriela Pérez-Lachaud ◽  
Mireille Campan

This paper relates a female age effect to the mating behavior of Chryseida bennetti Burks, an ectoparasitoid of the bean weevil (Acanthoscelides obtectus (Say)). The sexual behavior includes rapid courtship and copulation followed by a postmating courtship behavior ("guarding"). Male guarding behavior varies according to the females' age, with males guarding females of 2–3 days old longer than younger and older females. A period of sexual maturation is necessary for most of the males. Females' attractiveness begins at the pupal stage, and their receptivity on emergence. Mated females are still attractive to males. Multiple matings (up to four copulations) with the same male have been observed. The females' age seems to control copulation frequency and the duration of the postmating courtship behavior. Two- and three-day-old females had more successive multiple matings with the same male than the other females did, and males spent much more time guarding them. The age of the males (except from newly emerged males) did not seem to influence copulation frequency. On the other hand, the complexity of the sequential courtship behavior increased with the age of the partners. The function of males' postmating courtship is discussed.

Author(s):  
Paula Iraile Fernades Torres ◽  
Adriana Dantas Gonzaga de Freitas

Dentre as plantas com atividade inseticida, destaca-se o Pião-roxo (Jatropha gossypiifolia L), suas folhas possuem ácidos orgânicos, alcaloides, diterpenos, esteroides, flavonoides, lignanas e taninos. Este trabalho teve como objetivo investigar o potencial inseticida do J. gossypiifolia L para controle biológico de gorgulhos do feijão (Acanthoscelides obtectus Say). Foram preparados extratos com o uso do soxhlet tendo como solvente álcool etílico P.A. Os extratos foram obtidos a partir da diluição do extrato com água destilada, resultando nas concentrações 1:0,1:1/2,1:1,1:11/2 e 1:2. As placas foram pulverizadas com borrifadores manuais contendo os extratos, em suas respectivas concentrações. Em seguida, foram repassados 5 gorgulhos para cada placa. As observações foram realizadas durante 5 dias totalizando (120 horas). A testemunha foi pulverizada com água destilada. Todas as concentrações analisadas causaram mortalidade dos gorgulhos, a concentração 1:0 mostrouse como a mais eficiente em relação às outras concentrações, nessa concentração nas primeiras 24h do início dos testes em que se obteve 100% de mortalidade dos gorgulhos. As concentrações 1:1/2, 1:1 e 1:11/2 também se mostraram eficazes atingindo 100% da mortalidade dos gorgulhos, após 48h do início dos testes e a 1:2 foi a que atingiu uma menor taxa de mortalidade dos gorgulhos (80%) em comparação com as outras concentrações, todos os dados obtidos foram submetidos ao teste Tukey. Tal resultado agrega maior valor econômico e ecológico a esses produtos, que podem ser encontrados na maioria das propriedades rurais e por esses extratos botânicos apresentarem vantagens sobre os agrotóxicos por serem biodegradáveis.Palavras-chave: Inseticida Botânico. Controle Alternativo. Gorgulhos. Feijão.AbstractAmong the plants with insecticidal activity, it is worth mentioning the Purple Python (Jatropha gossypiifolia L), its leaves contain organic acids, alkaloids, diterpenes, steroids, flavonoids, lignans and tannins. This work aimed to investigate the insecticidal potential of J. gossypiifolia L for biological control of bean weevils (Acanthoscelides obtectus Say). The extracts were obtained from the dilution of the extract with distilled water resulting in the concentrations (1: 0.1: 1 / 2.1: 1.1: 11/2 And 1: 2). Plates were sprayed with hand sprays containing the extracts at their respective concentrations. Five weevils were then fed to each plate. Observations were performed for 5 days totaling (120 hours). The control was sprayed with distilled water. All the analyzed concentrations caused the weevils mortality, the concentration (1: 0) showed to be the most efficient in relation to the other concentrations, in that concentration in the first 24 hours of the beginning of the tests 100% mortality of the weevils was obtained. The concentrations 1: 1/2, 1: 1 and 1: 11/2 were also effective reaching 100% of the weevils mortality after 48h of the beginning of the tests and 1: 2 was the one that reached a lower mortality rate of the weevils (80%) compared to the other concentrations, all data were subjected to the Tukey test. This result adds greater economic and ecological value to these products, which can be found in most rural properties and because these botanical extracts have advantages over agrochemicals because they are biodegradable.Keywords: Insecticides Botanical. Alternative Control. Weevils. Bean.


1983 ◽  
Vol 61 (10) ◽  
pp. 2329-2337 ◽  
Author(s):  
Jean-Claude Biémont ◽  
Marc Jarry

The bean weevil Acanthoscelides obtectus, which is found over a large geographical area, can live in habitats where its host plant is not continuously available throughout the year. In such cases, the females must wait for favorable egg-laying conditions during part of the year. Individuals of this species may concentrate in temporary shelters such as dry leaves for example. The effect of the grouping of two individuals (female and male; female and female) on the reproductive physiology of females from a Cuban strain led to an inhibition or a decrease in oogenesis. This phenomenon was also observed when a female cohabited with a male whose aedeagus had been removed. However, oocyte maturation was stimulated when 4-day-old females were placed in the presence of a male for 4 h. The variability observed between two generations is discussed along with the often neglected role of relationships among individuals. The adaptive role of the inhibition of oocyte maturation induced by the grouping of two individuals is discussed.


1926 ◽  
Vol 4 (2) ◽  
pp. 186-195 ◽  
Author(s):  
GERT BONNIER

1. The time of development at 25°C. up to the moment of pupation is found to be for females and males respectively 116.62 ± 0.19 and 116.78 ± 0.20 hours. During the pupal stage the two times are 111.36 ± 0.15 and 115.46 ± 0.13 hours. 2. At 30° C. the corresponding figures are (in the same order): 99.95 ± 0.49, 103.37 ± 0.43, 78±15 ± 0.50 and 84.26 ± 0.34 hours. 3. These figures show that there is a statistical significance in the differences of the times of development of the two sexes for both the periods at 30°C. but only for the pupal stage at 25° C. It is pointed out that the fact that the longer time of male development as compared with female development at 25° C. is confined to the pupal stage, may be correlated with the other fact that the essential parts of the secondary sexual characters are developed during this stage. 4. It is shown that there is a negative correlation between the pre-pupal and pupal times of development, indicating that the longer the first time is, the shorter is, as a rule, the other time and vice versa. 5. With the aid of statistical methods it is shown that the shortening of the time of development at 30°C. as compared with the time at 25° C. is much more pronounced for the pupal than for the pre-pupal stage. 6. This last fact is discussed and it is emphasised that the ordinary methods of studying the influence of temperature on development are too rough to be of more than of a descriptive value, the only way of getting a deeper insight into the processes of development by temperature studies being the separate studies of a number of short intervals.


2019 ◽  
Vol 22 (10) ◽  
pp. 494-501
Author(s):  
Abo Iso Nta ◽  
Ann Afamefuna Jerry Mofunanya ◽  
Victoria Barrong Ogar ◽  
Theresa Ebia Omara-Acho ◽  
Patience Amara Azuik .

2000 ◽  
Vol 51 (1) ◽  
pp. 85 ◽  
Author(s):  
C. J. Lambrides ◽  
B. C. Imrie

Twenty-six mungbean varieties and accessions were screened for resistance to 4 bruchid species (Coleoptera : Chrysomelidae). On the basis of the percentage of seeds damaged all Australian commercial mungbean varieties tested here were highly susceptible to strains of Callosobruchus maculatus and C. chinensis, the 2 species that cause most damage worldwide to mungbean in storage. In addition, 3 accessions of wild mungbean appeared to have bruchid resistance. The texture layer present on the seed coat of some mungbean varieties and small seed size may act as oviposition deterrents. Consequently, these assays for determining resistance to bruchid infestation may not be suitable for identifying biochemical resistance of some mungbean genotypes.


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