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Dengue fever is a vector-borne infectious disease that spreads swiftly and threatens human lives in several tropical countries. Most of the strategies employed for the control of Aedes albopictus (Skuse) involve synthetic chemicals. The indiscriminate use of synthetic chemicals has led to the development of resistance and is unsafe for human and environmental health. Therefore, there is a need to develop ecologically safe tactics, such as the use of the entomopathogenic fungus (EPF) Metarhizium anisopliae (Metchnikoff 1879) (Met-11.1). The following study investigated the effectiveness of EPF-Met-11.1 on different demographic parameters of Ae. albopictus. Mortality bioassays showed 92.5% mortality when adult Ae. albopictus were treated with M. anisopliae. Metarhizium anisopliae absorbs the hemolymph sugar which results in retarded development. Metarhizium anisopliae LC50 not only affected the parental generation (F0) but also affected the demographic parameters of the offspring (F1). Transgenerational results (F1) with Met-11.1 showed decreased net reproductive rates (Ro), intrinsic rates of increase (r), and mean generation times (T) compared to those of uninfected controls. The larval developmental duration in the treatment group was 8.22 d, compared to 8.00 d in the control. There was a significant decrease in mean fecundity in the treated group (208.87 eggs) compared to that of the control group (360.27 eggs), and adult longevity was also significantly reduced in the treated group. Therefore, it is concluded that M. anisopliae can have lasting effects on the developmental parameters of Ae. albopictus, indicating that it can be an integral part of mosquito control strategies.

The sap and heart wooden stakes of Acacia nilotica var. indica, after seasoning and castor bean (Ricinis communis) oil application for exposure to workers of the termites, Odontotermes obesus (Ramb.), were placed in soil pits in completely randomised design with three replications. In each of seasoning and oil application, per cent weight loss of the wooden stakes were recorded and statistically analysed. Minimum per cent weight loss of sap and heart wooden stakes was observed in maximum period of seasoning (100°C for 15 days in oven drying and 60 days in sun drying method) and highest concentration of castor bean oil (20%) by vacuum pressure application. These results are discussed in relation to seasoning and castor bean oil application for wood protection against subterranean termites.

Symbiotic bacterial communities that colonize the digestive tract of tephritid fruit flies interact with nutrient intake to improve the flies' fitness and immunity. Some bacterial species consistently inhabit the tephritid guts and are transmitted to the next generation vertically. These species contribute significantly to some aspects of their host's physiology. In the current study, we examined the role of four vertically transmitted bacteria (Citrobacter, Enterobacter, Klebsiella, and Providencia) on the fitness parameters and immunity of Bactrocera dorsalis larvae that were fed a nutritionally manipulated diet. For this purpose, eggs were collected from axenic, gnotobiotic, and symbiotic adult flies, and larvae were reared on four types of diets in which carbohydrate and/or protein contents were reduced and then compared with larvae raised on a control diet. The diet and bacterial interactions significantly affected the fitness and immunity of B. dorsalis. Larvae of axenic flies grew slower and displayed weaker immune-based responses (PO activity, antibacterial activity, survival) than larvae of gnotobiotic and symbiotic flies. Overall, larvae reared on the low-protein diet grew slower than those reared on the control or low-carbohydrate diets. Survival, PO activity, and antibacterial activity were significantly lower in the hemolymph of larvae reared on low-protein diets. Our results also revealed that the levels of hemolymph protein, glucose, trehalose, and triglyceride in larvae from axenic flies were significantly lower than those in larvae of the symbiotic group after they fed on most of the tested diets. These results strongly infer that diet and vertically transmitted bacteria are both essential contributors to the fitness and immunity of B. dorsalis.