This study was carried out in 2015 to assess the level of resistance of sibling species of Anopheles gambiae complex the principal malaria vector from Bichi in Kano state to three classes of insecticides; (DDT, Permethrin and Bendiocarb) approved by World Health Organization (WHO) for vector control with the aim of obtaining baseline susceptibility and resistance data by evaluating the potency of brands of insecticides used against the mosquito vector in the area where the disease is prevalent. An. gambiae larvae collected from ecologically contrasting breeding sites were reared to adults in the laboratory. Adults from the F1 progeny were assayed for resistance using the WHO adult insecticide susceptibility bioassay protocol. The mosquitoes were exposed to DDT, permethrin and bendiocarb belonging to 3 classes of insecticides. The individual sibling species were identified molecularly and the molecular resistance mechanisms characterized by SINE and kdr PCR methods respectively. The An. gambiae populations tested revealed high level of resistance to DDT and permethrin but less resistant to bendiocarb. Analysis of the genetic composition of the vector population revealed predominance of An. coluzzii (> 77%). L1014F and L1014S kdr mutations correlated to insecticide resistance phenotype expression. This study indicates differential distribution of the resistant genotype of Anopheles malaria vector between ecologically different habitats in the area. This insecticide resistance represents a threat to vector control tool and should be monitored. The information obtained could be useful in decision and planning making for vector control programs in the region.

Malaria is an Anopheline mosquito-borne parasitic disease endemic to sub -Saharan Africa, which causes nearly 600,000 deaths every year. The distribution and transmission pattern are known to be affected by the ecological condition of the environment especially water and mesophilic conditions. Accordingly, irrigation-based rice producing system at Bunkure local government area of Kano state, Nigeria was followed up to assess malaria transmission rates. Four hundred and twenty-four (424) adult female Anopheles mosquitoes attracted to man were collected between August, 2010 and January, 2011 in wet and dry seasons in Bunkure Kano State. They were identified with a hand lens and taxonomic keys. The frequency of isolated Anopheline species constitutes 170 (33.2%) Anopheles gambiae and 129 (25.2%) Anopheles funestus for the wet season (August to October) vis-à-vis 72 (32.6%) Anopheles gambiae and 53(23.9%) Anopheles funestus for the dry season (November to January). Anopheline abundance were found in wet season. Mosquitoes that received blood meal were used to determine man biting rate. Blood fed were seen in both mosquitoes' species in irrigation system with man biting rate (MBR) per day, per month and per year 8.03, 240.6 and 2887.2 respectively. It was concluded that Bunkure LGA irrigation system area has high malaria transmission rate. The main entomological factors influenced malaria transmissions were the vector abundance, human blood index and daily survival rate. These factors were influenced by temperature, humidity, rainfall etc. This study provides information required for formulating vector control programmes to curtail malaria transmission in irrigated areas.

Pigeon pea's productivity has been stagnant over the years because of the devastating pest Helicoverpa armigera which causes major yield losses. The present study explored different responses of various defense strategies in leaves and pods of four pigeon pea cultivars (ICP-12142, ICP-11543, LRG-41 and CO-8) after infestation. Two pigeon pea cultivars viz; ICP-11543 and CO-8 were ascertained to be susceptible to infestation with excessive leaf and pod damage compared to the other two cultivars. Decreased activities of defensive enzymes/compounds like peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO) and total phenols were reported following infestation in cultivars of ICP-11543 and CO-8 which resulted in intensification of infestation. The cultivars; LRG-41 and ICP-12142 were found to be moderately resistant to pest infestation because of the up-regulation of PPO, POD and SOD along with accumulation of total phenols which might be held accountable for shifting the oxidative status of the respective cultivars.

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