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Fitness and behavioral traits are optimized according to the rearing environment to ensure survival of most organisms including fruit flies Drosophila melanogaster . Fruit flies are known to uphold various trade-offs in their lifespan, development time, fecundity, etc., to confer better survival in the particular exposed environment. The diet of D. melanogaster plays a major role between larval and adult fitness or fitness related traits; its role in the regulation of correlations between pupation height, pre-adult development and adult fitness has not been studied empirically. In our study, we assayed the effect of restricting dietary protein alone from the larval stage to adult stage in fruit flies and studied development time, pre-adult survivorship, pupation height, larval feeding rate and their corresponding lifespan under a light/dark cycle (LD12:12 h). We found that under very low protein concentration in diet, development time and lifespan of the flies increased significantly, along with decreased pupation height and vice versa, while pre-adult survivorship remained unchanged across diets. The results from our study can be taken to suggest that development time is negatively and positively correlated with pupation height and adult lifespan respectively. Thus, a higher protein restriction decreases pupation height and increases development time and vice versa, thereby emphasizing differential alterations taken up by various fitness traits, probably to enhance the overall organismal fitness.

Drosophila melanogaster has been used in Diet Restriction (DR) studies for a few decades now, due to easy diet implementation and its short lifespan. Since the concentration of protein determines the trade-offs between lifespan and fecundity, it is important to understand the level of protein and the extent of its influence on lifespan, fecundity and activity of fruit flies. In this study, we intend to assess the effect of a series of protein restricted diets from age 1 day of the adult fly on these traits to understand the possible variations in trade-off across tested diets. We found that lifespan under different protein concentrations remains unaltered, even though protein restricted diets exerted an age-specific influence on fecundity. Interestingly, there was no difference in lifetime activity of the flies in most of the tested protein restricted (PR) diets, even though a sex-dependent influence of protein concentrations was observed. Additionally, we report that not all concentrations of pR diet increase activity, thereby suggesting that the correlation between lifespan and the lifetime activity can be challenged under protein-restricted condition. Therefore, the PR does not need to exert its effect on lifespan and fecundity only but can also influence activity levels of the flies, thereby emphasizing the role of nutrient allotment between lifespan, fecundity and activity. Lifespan and fecundity are major fitness parameters that can assess the rate of aging and healthspan of organisms. It is suggested that lifespan and healthspan are no longer equivalent parameters and hence do not allow us to use lifespan alone to assess aging and fitness of an individual 1. For the past two decades, studies on the role of nutrition in the regulation of fitness and its related traits have been studied to understand the intricate process of aging. Nutritional studies employ techniques like calorie restriction, Diet Restriction (DR; henceforth), food dilution, intermittent feeding, etc., for a long time in a variety of animal models such as mice, fruit flies and nematodes 2-4. Since the validity of calorie restriction and food dilution has been debatable 5,6 , intermittent feeding and DR (involving restriction of one or more nutrients in the food, without causing malnutrition) have gained momentum in nutritional geometry studies. Numerous DR and aging studies have been done using fruit flies Drosophila melanogaster because of their ability to cater to a wide range of researches due to its shorter lifespan, well-understood genetics, and the presence of many equivalent genes in humans. Implementing reduced yeast (protein source in fly food) can be termed as Protein Restriction (PR; a type of DR). Several studies have shown that PR can extend lifespan and also result in a possible trade-off in fecundity 2,5. PR imposed on fruit flies D. melanogaster enables us to assess the effect of protein alone on fitness and fitness-related traits. Apart from the interplay between lifespan and fecundity upon DR, the locomotor activity of fl...

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Pesticide resistance is a common concern. It exerts close association with economic and health associated problems in various plants and other organisms. Several approaches have been trialled for attracting and trapping the insects and flies that are acting as vectors for transmission of communicable diseases. Although Drosophila melanogaster (fruit flies) is not an agricultural pest, its presence in consumer dwelling areas is an objection to human, as it indicates signs of an unhealthy environment or products. The current study focuses on the development of nanoemulsion with synthetic attractants and entrapping in sticky glue formulation that could provide prolonged effect for attracting and trapping the fruit flies. The results of our study showed the efficient attractive ability of exposed nanoemulsion (A3E1T) containing amyl acetate, ammonia, ethanol and Tween 80 compared to that of control. While the sex-based effect was not very prominent, the nanoemulsion showed a higher relative response index to the flies and increased activity even during their siesta time. Therefore, the nanoemulsion-based approach could be identified as one of the promising lines of attack and a suitable alternative for the existing fruit fly control measures. The present study is the first of its kind in reporting the ability of nanoemulsion formulation to attract and influence the activity of fruit flies D. melanogaster , up to our best of knowledge.