In a laboratory bioassay, adult female Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) spent more time near filter paper disks that had been exposed to adult males than near unexposed disks; this effect was not observed on disks exposed to adult females. The response could only partly be explained by the known male-produced aggregation pheromone, neryl (S)-2-methylbutanoate, suggesting the presence of an unknown male-produced compound. In gas chromatography/mass spectrometry analyses, 7-methyltricosane was detected on disks exposed to males, but not on disks exposed to females. Extracts of cuticular lipids also showed relatively large amounts of 7-methyltricosane on males, whereas only trace amounts were found on females and none on larvae. Bioassays of synthetic 7-methyltricosane showed that adults responded only after contact. The response to this compound was clearly different from that to n-tricosane or hexane-only controls. Females that contacted 7-methyltricosane on glass beads stayed in the vicinity and frequently raised the abdomen, a behavior that rejects mating attempts by males. Males stayed in the vicinity and wagged the abdomen sideways, a behavior used in fighting between males. This is the first identification of a contact pheromone in the order Thysanoptera.

Surveys were carried out in five local government areas of Ogbomoso Agricultural Zone Nigeria during planting season in 2010 to investigate rural farmers perceptions and management practices of insect pests of fruit vegetables. The survey involved 150 randomly selected farmers who were interviewed using structured questionnaire. Fruit vegetables planted by the farmers were okra, tomatoes, pepper and garden egg. Reasons given by farmers for cultivating fruit vegetables were significantly favored by age category, educational qualification, and secondary occupation of farmers (x 2 = 4.757, P = 0.029). Field insect pests were perceived as the major production constraint to fruit vegetables in this zone. Majority of the farmer estimated 78.4 % rated insect pest as the most serious pest infesting fruit vegetables, the insect pests were grasshopper (Orthoptera), beetles (Coleoptera) and caterpillar (Lepidoptera). Integrated pest management module consisted basically of chemical and cultural control strategies, with weeding, shifting cultivation and crop rotation as main cultural control methods. More than 76.7 % of the farmers make use of cultural control because of unavailability and cost of chemical insecticides. Only 23.3 % had access to chemical insecticides in controlling insect pest of fruit vegetables.

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Licensed under a Creative Commons Attribution 4.0 International License A field experiment was conducted in 2014 to determine insect pests associated with cucumber in Ogbomoso (Southern Guinea Savanna), Oyo-state Nigeria. Market More and Pointset cucumber varieties were used as treatments. Data were collected at three different phonological growth stages. Data collections commenced at 2 weeks after planting (WAP) and were on weekly basis for six weeks. Four major insect pests were observed namely Phyllotreta cruciferae Fabricius, Diabrotical undecimpunctata Howardi Barber, Epilachna vigintiopunctata Fabricius and Monolepta spp Coquilletta on the two varieties. Except Epilachna vigintiopunctata,which belong to the family Coccinellidae others are from the family Chrymesolidae. Also, all the insect pests recorded the highest population at seedling and the population reduces at flowering to fruiting stage while Epilachna recorded the highest population at fruiting stage. The same trend was also observed for distribution across the age of the plant.

The field study was conducted during the planting season of cowpea to evaluate the natural toxicant from Tephrosia vogelii and Petiveria alliacea and their mixture against Megalurothrips sjostedti and Apion varium at three different concentrations (5, 10, and 20% v/v). The experiment was set up in randomized complete block design. The field observations showed that the two insect pests were effectively controlled by the botanical insecticides compared with untreated plants. Also, the plant extracts at 20% and 10% v/v significantly protected cowpea pods and grains from the damage. However, higher grain yield was obtained from the plant treated with 20% v/v compared to those treated with 10%, 5% v/v and untreated plants. Combination of the two plant extracts at 20% v/v had the same efficacy with synthetic insecticide (Decis). Thus, these plant extracts can be used in organic farming.

Surveys were carried out in five local government areas of Ogbomoso Agricultural Zone Nigeria during planting season in 2010 to investigate rural farmers perceptions and management practices of insect pests of fruit vegetables. The survey involved 150 randomly selected farmers who were interviewed using structured questionnaire. Fruit vegetables planted by the farmers were okra, tomatoes, pepper and garden egg. Reasons given by farmers for cultivating fruit vegetables were significantly favored by age category, educational qualification, and secondary occupation of farmers (x2 = 4.757, P = 0.029). Field insect pests were perceived as the major production constraint to fruit vegetables in this zone. Majority of the farmer estimated 78.4 % rated insect pest as the most serious pest infesting fruit vegetables, the insect pests were grasshopper (Orthoptera), beetles (Coleoptera) and caterpillar (Lepidoptera). Integrated pest management module consisted basically of chemical and cultural control strategies, with weeding, shifting cultivation and crop rotation as main cultural control methods. More than 76.7 % of the farmers make use of cultural control because of unavailability and cost of chemical insecticides. Only 23.3 % had access to chemical insecticides in controlling insect pest of fruit vegetables.

ABSTRACT. Organochlorine pesticide residues in dried cocoa beans from selected towns in Ondo and Osun States, Nigeria were determined. Four towns Ondo and Idanre (Ondo State) and Ife and Ilesa (Osun State) were selected to represent cocoa producing areas in the states. Samples were extracted and cleaned-up on silica gel adsorbent. Pesticide residues were detected using Gas Chromatography -Mass Spectrometry (GC-MS). Five organochlorine pesticides were detected in the samples from Ondo state which includes alpha-HCH, beta-HCH, delta-HCH, endrin and p p' DDT. The levels of p p' DDT (0.108 mg/kg and 0.107 mg/kg) detected in samples from Ondo and Idanre towns were lower than the EU MRL (0.5 mg/kg), while other detected organochlorine pesticide residues from the State were higher than the EU MRL. In Osun State, alpha-HCH, lindane, dieldrin, endrin, heptachlor-epoxide, endosulfan I and p p' DDT were organochlorine pesticide residues detected, with lindane (0.074 mg/kg), endosulfan I (0.099 mg/kg) and p p' DDT (0.235 mg/kg) being lower than EU MRLs. Higher levels of organochlorine pesticide residues than the EU MRLs suggest that the produce were not safe for human consumption because of the tendency of the pestsides to persist for a long period of time and as well bioaccumulate within the environment. The produce can also face trade threat in international market. Measures were suggested to ameliorate this situation.