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In this study, the Chemical composition and bio-efficacy of essential oils (EOs) from Anethum graveolens, Thymus vulgaris, and Myristica fragrans were assessed. Seventeen, forty-five and twenty-nine compounds were identified in A. graveolens, T. vulgaris, and M. fragrans, respectively by GC-MS analysis. Dillapiole (44.01 %), D-Limonene (19.47 %), and carvotanacetone (13.03 %) in A. graveolen EO; estragole (15.30 %), γ-terpinene (14.49 %), and thymol (10.80 %) in T. vulgaris EO; safrole (14.93 %), α-terpinolene (14.65 %), and elemicin (14.62 %), in M. fragrans EO, were the main compounds. The bio-efficacy of these essential oils was tested against adults of major insect pests namely Callosobruchus maculatus using fumigant toxicity and biological parameters. Results revealed that the A. graveolens EO was the most toxic oil against C. maculatus adults with LC50 and LC90 values of 10.1 and 25.5 μl/l air, respectively after exposure for 24 h. EO of A. graveolens killed C. maculatus adults faster than T. vulgaris and M. fragrans. A. graveolens and T. vulgaris showed the highest effect on biological parameters of oviposition. This study suggests that EO from A. graveolens could be potentially using in IPM programs for suppressing this pest in infesting cowpea seeds. [ABSTRACT FROM AUTHOR]

In order to develop a strategy for the safe management of insect pests in stored agricultural commodities, Anserine (Chenopodium ambrosioïdes (L.)) essential oil was tested against Cowpea weevil (Callosobruchus maculatus) raised on seeds of Chickpea (Cicer arietinum) at 20–30°C and 65 ± 5% relative humidity in storage conditions. The essential oil extracted from Chenopodium ambrosioïdes (L.) was analysed by gas chromatography coupled with mass spectrometry (GC/MS). The chromatogram of the essential oil of Chenopodium ambrosioïdes (L.) contains 13 compounds of which α-Terpinene is the majority constituent with a percentage of 61.04%. The results obtained have shown that the essential oil of Chenopodium ambrosioïdes (L.) has repellent and toxic effects on Callosobruchus maculatus. It causes a high mortality rate in adults and affects its fecundity, fertility and success rate in a very significant way compared to controls. [ABSTRACT FROM AUTHOR]

Citrus which belong to family Rutaceae is one of the most important commercial crops with a growing demand. Outer peel of Citrus fruits of several species is known to possess oil with some insecticidal properties. The one year study was thus carried out to evaluate the repellent and toxic effects of the fruit peel powder of Citrus nobilis and Citrus medica against pulse beetle, Callosobruchus maculatus. Increasing repellent activity against insects was observed with increasing dose for both plants where the highest repellency was elicited by C. nobilis. Significant reduction in oviposition, egg hatchability and adult emergence were observed in both Citrus species. Moreover, no significant effects were observed on seed viability and consumer acceptability between control and treatments. Chemical constituent characterization revealed, d-Limonene to be the major constituent of both C. nobilis (45.3%) and C. medica (68.3%) plant species. Overall results indicate high potential of both Citrus species, particularly C. nobilis as a repellent, toxicant and growth inhibitor to reduce the damage caused to leguminous crops by C. maculatus. [ABSTRACT FROM AUTHOR]

The present study is carried out to evaluate the effect of nine faba bean varieties on certain life aspects of Bruchidius incarnatus (Boh.) (Bruchidae: Coleoptera) in non-choice and free-choice tests. The variables that were determined from the experiment were: the number of laid eggs (fecundity), ovipositional period, incubation period, percentage of hatching eggs and percentage of ovipositional preference. The results for Giza 843 was as following: the numbers of laid eggs were 83.0 ± 2.02 and 40.33 ± 0.33 eggs, the ovipositional periods were 4.66 ± 0.66 and 4.33 ± 0.88 days, the incubation periods were 4.0 ± 0.57 and 5.33 ± 0.33 days, the percentage of hatching eggs were 96.79 ± 0.80 and 90.06 ± 2.53% and the percentage of ovipositional preference were 16.29 ± 0.39 and 15.54 ± 0.09%; respectively for no-choice and free choice tests. Also the results for Giza 3 was the numbers of laid eggs were 34.0 ± 2.08 and 18.66 ± 0.66 eggs, the ovipositional periods were 6.0 ± 0.57 and 7.0 ± 1.0 days, the incubation periods were 7.33 ± 0.88 and 9.0 ± 0.0 days, the percentage of hatching eggs were 87.48 ± 2.22 and 82.40 ± 4.03% and the percentage of ovipositional preference were 6.76 ± 0.48 and 7.19 ± 0.25%, respectively for no-choice and free choice tests. Generally, the study concluded that Giza 843 is the most preferred variety for B. incarnatus, whereas Giza 3 is the undesirable variety to B. incarnatus. [ABSTRACT FROM AUTHOR]

Acetone and chloroform extracts of the seed ofXylopia aethiopica(Dunal) A. Rich (Annonaceae) were evaluated in the laboratory for their insecticidal effect on the adultCallosobruchus maculatus(Fabricius) (Coleoptera: Bruchidae). Adult mortality was assayed using 0.5ml and 1.0 ml of extract per 20 g cowpea. Five dosages (0.2, 0.4, 0.6, 0.8 and 1.0 ml) ofX. aethiopicaextracts per 20 g cowpea seed were used to determine the oviposition, adult emergence and seed damage byC. maculatus. Untreated control and solventtreated control were included. At 3 and 5 days after treatment (DAT),percentage mortality was significantly (p<0.05) higher in cowpea treated with chloroform extract (46.53%, and 62.45%, respectively) than what obtained in acetone extract (34.2% and 52.43%, respectively) ofX. aethiopica. Application of extract at 1.0 ml/20 g seed caused significantly (p<0.05) higher percentage mortality when compared with the solvent treated controls. The LD50(0.42 and 0.02 ml/20 g seed) for chloroform extract at 3 and 5 DAT were smaller than values for acetone (0.78 and 0.17 ml/20 g seed) at the same duration after exposure, respectively. LT for acetone and chloroform extract was 2.21 and 1.76 h, respectively. The number of eggs laid on cowpea treated with 1.0 ml/ 20 g seed was significantly (p<0.05) lower than the number of eggs laid on the solvent-treated control and seeds treated with 0.2 ml/ 20 g. Percentage seed damaged significantly (p<0.05) decreased with increased concentration, while the highest damage was obtained in solvent-treated cowpea seeds. [ABSTRACT FROM AUTHOR]

Bruchid-induced damage, lethal and deterrent indices ofCymbopogon citratus,Alstonia boonei,Hyptis suaveolens,Azadirachta indica,Loranthus brauniiandLycopersicon esculentumwere investigated on Oloyin and IT845-2246 cowpea varieties at 0.00, 0.625, 1.25, 2.50 and 5.00% (w/w) under laboratory conditions (29 ± 3 °C and 65 ± 5% R.H.). The experiment was laid out in 6 × 5 × 2 factorial arrangement fitted into a completely randomised design with four replicates. Results showed that irrespective of cowpea variety, the lowest bioactive concentration at which adult bruchid emergence was significantly deterred was 1.25%. A hundred percent mortality was recorded withH. suaveolensat 1.25% concentration with Oloyin, and withC. citratusandA. booneiat 2.50 and 5.00. The powders also caused outright inhibition and reduction in adult bruchid emergence in the third filial generation. ForH. suaveolensandC. citratus, lethal concentrations (LC50) were 0.073 and 0.080 on Oloyin and IT845-2246, respectively. Also,C. citratusandA. indicahad the highest oviposition deterrence DC50values, 1.42 and 1.68. Results showed that bioactivity which was lower on Oloyin compared to IT845-2246, depended on cowpea’s accession used and was not dose-dependent. Powders of any of the tested plant species may be effectively exploited for bruchid control in stored cowpea grains at reduced concentration of 1.25% provided. [ABSTRACT FROM AUTHOR]

Fumigant activity of essential oil vapours distilled fromZingiber officinale(L.) andMentha pulegium(L.) was tested against eggs, larvae and adults ofCallosobruchus maculatus(F.). Fumigant toxicity was assessed at 27 ± 1 °C and 60 ± 5% RH, in dark condition. The influence of different concentrations of the essential oil vapours on egg hatchability, larval and adult mortality was significant. Data probit analysis showed that lethal concentration of the essential oil to kill 50% of the population (LC50) for egg, larvae and adult was found to be 1.151, 2.336 and 2.183 μl/l air ofZ. officinale, followed by 0.072, 0.113 and 0.093 μl/l air essential oil ofM. pulegium, respectively. Between these essential oils,Z. officinaleis almost more toxic thanM. pulegiumon all growth stages ofC. maculatus. The present study suggests that essential oils from these medicinal plants may be potential grain protectants as botanical alternative fumigants and could be used in the management of various life stages ofC. maculatus. [ABSTRACT FROM AUTHOR]

The development of cowpea weevil,Callosobruchus maculatus(Fabricius) (Col., Bruchidae), and its parasitoid,Anisopteromalus calandrae(Howard) (Hym., Pteromalidae), under nine constant temperatures and the best linear and non-linear models describing the temperature-development relationships of the host and its parasitoid were determined. The pre-imaginal developmental time decreased with increasing temperature from 15° C to 35° C for both species and sexes. Based on the best-fitted linear model, the lower developmental threshold and the thermal constant were determined as 10.4° C and 526.3 degree-days forC. maculatusand 11.5° C and 263.2 degree-days forA. calandrae, respectively. Fifteen non-linear temperature-dependent models were examined to find the best model to describe the relationship between temperature and development rate ofC.maculatusandA. calandrae.Among non-linear models, the Analytis model was the most efficient for the description of temperature-dependent development ofC.maculatusandA. calandrae. [ABSTRACT FROM AUTHOR]

Eighty cowpea accessions comprising both improved and local were assessed for their resistance toCallosobruchus maculatus(F.) attack under laboratory conditions (29 ± 3?°C and 65 ± 5% R.H.). Sixty-nine accessions were derived from the International Institute for Tropical Agriculture breeding programmes, four were local cultivars, while seven were improved cultivars from national research institutes. Results showed that there were significant differences among the accessions in terms of number of initial bruchid eggs laid on them, adult emergence, number of seeds damaged and bruchid-induced seed weight loss at three months after artificial infestation withC. maculatus. On IT04K-334-2, IT04K-343-1, IT06K-141, IT99K-216-48-1, IT99K-494-6 and IT99K-529-2, fewer initial eggs were laid and no adult emergence, seed damage or weight loss and were considered highly resistant toC. maculatus. On the other hand, IT03K-337, IT04K-217-51, IT04K-332-1, IT04K-339-1, IT06K-188-49, IT81D-1137, IT845-2231-15, IT93K-452-1, IT04K-154-1, IT96K-610, IT97K-1069-6, IT97K-390-2, Ife Bpc, IT99K-573-2-1, Ife Modupe, IT845-2246, Drum, Ife Brown and Oloyin were the most susceptible with the highest damage indices values (p?

In this study, the insecticidal effect of Poppy (Papaver somniferum) seed oil was investigated againstCallosobruchus maculatus(Bruchidae) in cowpea, at different concentrations and exposure time. The Poppy seed oil at 2, 4, 6, 8 and 10 ml/kg was tested against adults ofC. maculatus, and the mortality was counted after 24, 48 and 72 h of exposure. All tests were conducted at 27–30 °C and 65 ± 5% r.h. The experiments were carried out based on the factorial experiment by randomized complete design with four replications. Twenty-five insects with 0–24 h old were used for each replication. The effect of Poppy seed oil on the reduction of emergence of insects in next generation (F1) was also assayed. The results of experiments indicate the significant differences between concentrations and exposure time (p < 0.0001), and the increase of concentrations and exposure time increased mortality. The amount of mortality at high concentrations was remarkable, and highest mortality rate (96.91%) was recorded at 10 ml/kg, after 72 h of exposure. The application of oil significantly reduced F1progeny production and even at lowest concentration (2 ml/kg), the amount of F1production was reduced more than 70%, compared with control treatment. Complete (100%) reduction in progeny production was recorded at the rates of 8 and 10 ml/kg. The results of seed germination assay showed no significant differences between control and treated seed, and no harmful effect was observed on the seed germination. These results proved that Poppy seed oil can be used as a controlling agent of storage pests, especiallyC. maculatus, although more detailed studies are necessary. [ABSTRACT FROM PUBLISHER]

Three species of gull-like birds were described by Milne-Edwards in the 19th century from the early Miocene of Saint-Gerand-le-Puy, France, two of which have been since then moved to the genus Laricola. These fossils are redescribed and revised in the present study. We further describe two new species of the taxon Laricola, L. intermedia, sp. nov., and L. robusta, sp. nov., as well as two species of a new taxon Sternalara, S. minuta and S. milneedwardsi, thus substantially increasing the number of charadriiform taxa known from this locality. To find out how Laricola relates to modern taxa, we performed a phylogenetic analysis of 41 osteological characters, which resulted in Laricola being placed outside of Lariidae, as early representatives of the newly designated group Laromorphae, which encompasses terns, gulls, and skimmers. The results of our analysis have additionally enabled us to evaluate relationships between extant taxa of the Laromorphae. [ABSTRACT FROM AUTHOR]

A comparative study on the efficacy of powder and oil extracts from leaves and seed kernels of Azadirachta indica Juss. and Eucalyptus camaldulensis Dehn. against the seed weevil Caryedon serratus Olivier infesting seeds of Acacia seyal Del. was carried out. EO 1, EO 5 and NSKO5% were comparable to BHC 3% in significantly reducing egg laying by C. serratus. With the exception of ELP and NLP, all botanicals significantly reduced egg hatching. Botanicals significantly reduced larval development with the exception of ELP and NLP. EO and NSKO at 3 and 5% were significantly more effective than BHC in reducing larval development by 95-97%. All botanicals had no significant effect on adult emergence which was only affected by BHC. Botanicals caused 4.3-43% mortality of C. serratus adults and the maximum mortality occurred in EO 3% as compared to BHC. It is apparent that oils extracted from E. camaldulensis had a fumigant and knock down effect on adult C. serratus. Extracted oils were more effective than leaf or seed powder. Oils extracted from leaves of E. camaldulensis were volatile and had a knock down effect on adult C. serratus indicating the possibility of using them as alternative fumigants in seed stores. [ABSTRACT FROM AUTHOR]

Plant based insecticides are gaining importance for their environmental safety. But their efficacy is greatly reduced in the field due to several factors. This study was undertaken to assess the insecticidal properties of medicinal plants viz., Cassia tora, Clerodendron enermi, Calotropis gigantea, Aloe vera, Vitex negundo and Andrographis paniculata, commonly found on farmlands and their mixtures. The extracts and mixtures were bio-assayed against a lepidopteran larva (Heliothis armigera) by modified leaf dip bioassay, and its effect on larval growth, development and survival; the oviposition deterrent effect against moths of H. armigera, and efficacy against the sucking pest Aphis gossypii and a stored product pest Callosobruchus chinensis were studied. The insecticidal activity in descending order was as follows: NSKE 10% > NSKE 5%, Botanical mixture II > A. paniculata > V. negundo > Botanical mixture I > C. gigantea > C. tora > C. enermi > A. vera. All botanicals showed greater ovipositional deterrence than insecticidal activity exhibiting 40-100% inhibition compared to untreated control. A. paniculata showed the highest activity against the store product pest C. chinensis. The complex of compounds in botanical mixtures could be synergistically used in eco-friendly pest management and botanical mixtures with neem as one of the ingredients, which could have a potential role as insect growth regulator. [ABSTRACT FROM AUTHOR]

Acanthoscelides obtectus is a bruchid beetle that oviposits into ripening bean pods in the field. More precise data are needed for developing management strategies for small-scale farmers in East Africa. In farmers' fields, an infestation rate of 6.9% infested bean seeds was recorded in dry pods, but in wilting yellow pods there was a lower infestation of 2.5%. No wilting green pod had been infested. After releasing 680 bruchids in an open field, the infestation rate in dry pods increased to 39 and 7% in wilting yellow pods, but again no wilting green pod was found to be infested. In no-choice laboratory trials, however, A. obtectus infests wilting pods; and pod aperture did not influence infestation rates. Stimulants for oviposition were evaluated in no-choice trials. Bean pods containing seeds were as attractive as bean seeds alone, and significantly more attractive as empty opened bean pods. Bean pods without seeds were more attractive than the empty control. The natural infestation rate in fields close to homesteads was higher than in fields more than 1 km away from any habitation. Farmers are advised to be aware of the infestation danger in the field, and to consider early harvest if they have infestation-free storage. [ABSTRACT FROM AUTHOR]

Laboratory assays were carried out to evaluate the effects of fresh Cleome viscosa on the reproduction and survival of Callosobruchus maculatus. Significant control was achieved by the two treatments with the highest quantity of crushed leaf. Fresh crushed C. viscosa also led to complete inhibition of embryonic development of eggs exposed for 48h in all botanical treatments. On-farm storage trials, using 5, 15 and 25 g C. viscosa crushed plant per 1 kg of cowpeas, showed a dose-dependent reduction in bruchid numbers of 35.4, 59.5 and 86.4%, respectively, after 120 days of storage. Moreover, the pea losses were relatively low (≤11%) and pea germination was unaffected (>80%) in all batches where C. viscosa was introduced. Our results indicate that C. viscosa has significant potential for controlling the pest. The conditions for optimal use of the plant in stored cowpea management are discussed. [ABSTRACT FROM AUTHOR]

The nut and shell of cashew ( Anacardium occidentale L.) were evaluated for insecticidal efficacy at concentrations of 2.5, 5.0 and 7.5% per 150 g bambarra groundnut ( Voandzeia subterranea L.) Verde seeds against Callosobruchus subinnotatus (Pic.) (Bruchidae). Cashew nut shell was highly toxic to C. subinnotatus and achieved 100% insect mortality within 48 hours at 7.5% and 100% mortality within 72% hours at 2.5 and 5.0% concentrations. Oviposition and progeny development of the insect were severely suppressed while seeds were protected from damage by the bruchid. Seed germination was, however, impaired at all concentrations, suggesting that seed treated with cashew products may be suitable for consumption but not be suitable as planting stock. [ABSTRACT FROM AUTHOR]

The use of beni seed, Hyptis spicigera Lam. (Labiatae), to protect stored cowpeas from bruchid attacks is a widespread practice in West Africa. More knowledge about its actual effects on storage pests is needed to enhance its effectiveness. In this laboratory study, repellent and lethal effects of powder and essential oil from H. spicigera on Callosobruchus maculatus , the main pest of stored cowpeas, were studied. Repellency tests undertaken with a Y-tube olfactometer showed that powder was repulsive for C. maculatus adults. On the other hand, this product had no insecticidal activity. Essential oil had a dose-dependent insecticidal effect while sublethal doses repelled the adults. Both products reduced oviposition by 15 – 19 and 7 – 78% according to the doses of powder and essential oil, respectively, tested. Similarly, egg viability decreased with increasing doses of powder and essential oil used in a range of 40 – 75 and 24 – 86%, respectively. Only essential oil was lethal to C. maculatus larvae developing within cowpea seeds; however, oil activity was age-dependent, younger instars being more susceptible. These results are discussed with a view of controlling C. maculatus populations in stored cowpeas. [ABSTRACT FROM AUTHOR]

Savalli & Fox (1999) have recently shown that in the bruchid beetle Callosobruchus maculatus, females inseminated by large males lay more eggs than those inseminated by small males. Here we report the results of a very similar experiment, on the same species, which yielded the opposite result; females inseminated by small males laid more eggs than those inseminated by large males. On analysing the methods and results, two differences in experimental design become apparent; male age at first copulation and population origin. We suggest these two differences may have produced the contrasting results and believe they offer important evolutionary and developmental insights into ejaculate composition. [ABSTRACT FROM PUBLISHER]

We use laboratory mating experiments to examine the effect of male size, age, and mating behavior on fecundity selection and sexual selection in the seed beetle, Callosobruchus maculatus (Coleoptera Bruchidae), a species in which females are larger than males. Female C. maculatus gain a fitness advantage, in the form of increased lifetime fecundity, from mating with large males (which contribute larger ejaculates), but the partial correlation between male size and fecundity is weaker than the partial correlation between female size and her fecundity. Large males had a mating advantage relative to small males, both when a single male was presented to a female and when two males were present. However, this did not appear to be due to females rejecting male courtship attempts, but instead may be due to male-male competition. When females were mated to two males sequentially, neither the size of the first male nor the size of the second male influenced whether or how quickly a female remated. None of the other potential bases for sexual selection — male age, male mating experience, and male courtship persistence — appeared to influence male mating success. We discuss how patterns of sexual selection on body size and sexual size dimorphism in C. maculatus differ from patterns of sexual selection and dimorphism in another seed beetle, S. limbatus. [ABSTRACT FROM PUBLISHER]

Abstract. Four bruchid beetle control methods using: corn oil, wood ash, sunning and sieving (S&S) and insecticide (1.6% pirimiphos-methyl/ 0.3% permethrin ), were evaluated to determine their efficacy, effect on germination, seedling vigour and appearance of bean seeds. Efficacy was assessed by the percentage of damaged seeds and number of emerged bruchids in 250 g lots ofbean grain after 4 months ofstorage in glass jars in the laboratory. Germination was assessed by the percentage germination of groups of 10 clean seeds per pot in the greenhouse 7 days after planting. Seedling vigour was estimated by the fresh weight of 7 day old seedlings. There were significant differences among treatments in the percentage of damaged seeds ( P < 0.05) and emerged bruchids ( P < 0.001), but none in the germination and seedling vigour. Corn oil and S&S were as effective as insecticide in bruchid control, however S&S was the better of the two since it did not affect germination, seedling vigour or grain appearance. On-farm testing of S&S in 13 randomly selected farms showed that it was as effective as insecticide in bruchid control, however farmers preferred S&S due to its safety, low cost and maintenance of grain cleanliness. [ABSTRACT FROM AUTHOR]

Root bark powder and extracts of Zanthoxylum zanthoxyloides significantly (t = 0.05) reduced the competitiveness of male cowpea seed bruchid (Callosobruchus maculatus F.). Observed pairings involving males exposed to the root bark powder and acetone, hot water and cold water extracts were 0, 1.6.0, 23.0, and 25.7 percent, respectively. Receptiveness of treated females to courting males was also decreased by exposure to root bark powder and extracts. Constituents in root bark powder, terpenoids, phenolics, alkaloids, and N-oxides, significantly reduced ovipositioning by 39.6 to 63.4 percent, adult emergence by 13.9 to 50.2 percent, and seed attack by 69.3 to 92.8. Zanthoxylum zazthoxyloides root bark products have potential as seed protectants against the cowpea seed bruchid. [ABSTRACT FROM PUBLISHER]

Abstract. Eight local cultivars of cowpea that have been improved for higher yield and pest tolerance which were recently released for cultivation by the International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, were compared with respect to their susceptibility to the cowpea bruchid beetle, Callosobruchus maculatus (F.) under laboratory conditions (30 - 35 C and 45 - 57% RH). Cultivars Kanannado, T189KD391 and Dan`ila with susceptibility indices (SI) of 0.0, 2.2 and 2.6, respectively, were found to be resistant to bruchid attack and cultivars Babura-4, IT89KD-374, Bausse-local, IT89KD-349 and Aloka-local with SI values of 11.2, 10.9, 7.5, 7.2 and 6.5, respectively, were found to be susceptible. Oviposition and egg viability were significantly reduced on seeds of the resistant cultivars. The total mean number of eggs laid on seeds of the resistant cultivars Kanannado, IT89KD-391 and Dan`ila were 16, 15 and 6, respectively, while 50, 44, 36, 35 and 26 eggs were laid on seeds of susceptible cultivars Babura-4, IT89KD-374, Bausselocal, Aloka-local and IT89KD-349, respectively. The proportion of unhatched eggs laid on resistant cultivars was 98.2, 81.5 and 50.0% for Kanannado, IT89KD-391 and Dan`ila, respectively, while 9.2, 13.1 and 14.8% ofeggs remained unhatched on the susceptible cultivars Bausselocal, Babura-4 and IT89KD-374, respectively. [ABSTRACT FROM AUTHOR]