Factors determining the use of botanical insect pest control methods by small-holder farmers in the Lake Victoria basin, Kenya

A farm survey was conducted in three representative administrative districts of the Lake Victoria Basin (LVB), Kenya to document farmers’ indigenous knowledge and the factors that influence the use of botanicals instead of synthetic insecticides in insect pest management. A total of 65 farm households were randomly sampled using stratified sampling procedure. The maximum likelihood log model was used to determine factors that influence use of botanical and synthetic insect pest control methods (PCM). Results revealed that female gender as household head (HH) and age significantly (P < .001) increased the likelihood of a household using botanical PCM in the field by 0.15 and 0.021, respectively. In storage, female gender and severity of pest infestation significantly (P < .001) increased the probability of a household using botanical insecticide by 0.814 and 0.738, respectively. On the contrary, education of HH (0.342) and ownership of title to land (0.512) significantly (P < .001) reduced the likelihood of using botanical PCM in the field, while traditional rank (0.910) and cash rank (0.744) of the crops reduced the likelihood of using botanical insecticides in the store. With respect to synthetic pesticides, gender (3.407), area cultivated (0.295) and expected yield (5.315) significantly (P < .001) reduced likelihood of their use in the field, while food rank (3.967) reduced the probability of use in storage. In storage, female gender, crop type, food and traditional rank of crops were also the most important factors determining the use of botanical control methods. In conclusion, the study established that female gender, literacy levels, wealth endowments in form of land and old age are key determinants of botanical insecticides use in small-holder farming systems in the LVB, Kenya. It is recommended that the Government of Kenya enacts policies that empower youth and female gender economically in subsistence farming with the aim of improving their educational levels and farming skills to modernize agriculture among the rural communities.Key words: Botanical, Synthetic pesticide, Insects, Pest control method, Determinants, Small-holder farmers

Pesticidal Activity of Wild Mushroom Boletus satanas Lenz Extracts against Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) in Stored Maize Grains

Boletus satanas Lenz (Boletaceae) is a basidiomycete fungus reported to contain monomeric glycoproteins (lectins) which are known to possess insecticidal, larvicidal, ovicidal and anti-nutritional activities. This study was carried out to assess the toxicity, anti-feedant and repellence potential of the crude methanol extract of the mushroom in stored maize grains. Six levels of concentration ranging from 0.05 to 0.5% w/w were used during the assessments. Untreated grains and grains treated with 2% Actellic gold TM dust (0.05% w/w) were used as negative and positive controls, respectively. The experiments were carried out in a completely randomized design with three replicates made for each treatment level and controls. The 0.5% w/w methanol extract exhibited the highest mean mortality of 68.3% and 94.2% inhibition in F1 progeny. Moreover, 89.7% reduction in grain damage and 98.3% pest repellence were observed. These findings render credence to the use of B. satanas as a potential biopesticide by subsistence farmers to preserve grains and corroborate the ongoing IPM strategies

Levels and Exposure Risks of Lead, Arsenic and Mercury from Selected Lipstick and Nail Polish Cosmetics Marketed in Dar es Salaam, Tanzania

Abstract Presence of Pb, As and Hg in selected lipstick and nail polish cosmetics sold at different shopping malls and retail outlets in Dar es Salaam was determined by microwave plasma atomic emission spectrometry due to their public health effects. Pb was detected in 100% (n = 25) of lipsticks and 53.3% (n = 15) of nail polishes. Arsenic was detected in 36% of lipsticks and 86.7% of nail polishes, and Hg was detected in 44% of lipsticks and 80% of nail polishes. All metal levels in both cosmetics were below the World Health Organisation (WHO) and Tanzania Bureau of Standards (TBS) maximum recommended limits. Health-based risks were evaluated using chronic daily intake (CDI), non-carcinogenic hazard quotient (HQ), hazard index (HI) as well as carcinogenic total risk. CDI values in all cosmetics were lower than maximum tolerable daily intake (MTDI). HQs of all metals in most of the lipsticks and all nail polishes were < 1, indicating little health risks. Both HI and carcinogenic risk were lower, indicating that they are relatively safe and have little potential carcinogenic risk. Determined potential carcinogenic risks were lower, indicating little carcinogenic risk. Awareness of potential effects and continuous monitoring are recommended to raise awareness of consumers and control quality of cosmetics as metals are cumulative toxicants

Residual contact toxicity and repellence of Cupressus lusitanica Miller and Eucalyptus saligna Smith essential oils against major stored product insect pests

In an effort to find eco-friendly alternatives to synthetic pesticides in grain storage, residual contact toxicity and repellence of Cupressus lusitanica and Eucalyptus saligna leaf essential oils were evaluated against adult Tribolium castaneum, Acanthoscelides obtectus and Sitophilus zeamais. In bioassays, oil was applied at 0.00, 0.05, 0.10, 0.15 and 0.20% v/w to wheat and bean grains and stored for 30–120 days after which test insects were introduced into sub-samples of treated grains. Both oils at 0.20% v/w and 120 days grain storage duration caused a mortality of 5.0–65.0% in test insects whereas in the repellence bioassay, at same doses and grain storage duration produced percent repellence values of 34–52.4% of test insects. Considering other pesticidal properties of C. lusitanica and E. saligna oils, current results point oils as potential residual contact toxicants and repellents for possible integration into insect pest management practices

Chemical composition of Cupressus lusitanica and Eucalyptus salignaleaf essential oils and bioactivity against major insect pests of storedfood grains

The leaf essential oils from Cupressus lusitanica, Miller and Eucalyptus saligna, Smith obtained by hydrodis-tillation were analyzed by GC/MS and also screened for their insecticidal and repellent effects against adultTribolium castaneum, Acanthoscelides obtectus, Sitotroga cerealella and Sitophilus zeamais. The C. lusitanicaoil contained mainly umbellulone (18.38%) and �-pinene (9.97%) whereas the E. saligna oil was domi-nated by �-pinene (24.40%) and 1,8-cineole (24.26%). Bioassays showed that of the four insect speciestested, A. obtectus and S. cerealella were the most susceptible to the oils, with LC50values of 0.05–0.11%v/w in contact toxicity and 4.07–7.02 �l/L air in space fumigation. Except in T. castaneum with percentagerepellence (PR) values of 65–92.5%, the other test insects recorded PR values less than 30%. The PR valuesdecreased with exposure time in all insects except in T. castaneum. Our results show that C. lusitanica andE. saligna essential oils are promising insecticides and repellents to be used against insect pests of storedfood grains