Variations in the esterase expression pattern with respect to different light regimes in Drosophila agumbensis and Drosophila nagarholensis

Circadian clock enables organism's to adapt under fluctuating environmental conditions by coupling of behavioral, physiological and molecular processes in a wide variety of organisms including bacteria, fungi, plants, birds and mammals. The endogenous circadian system functions to organize behavior and physiology to adapt to and anticipate environment changes in light and temperature. The present study is an attempt to understand enzyme profiles (alpha- and beta-esterases) of Drosophila agumbensis and Drosophila nagarholensis under light/dark (LD), constant dark (DD) constant light (LL), conditions over twenty generations. A polyacrylamide gel electrophoresis (7.5% - Native gel) was used to study the esterase expression patterns in two species of the montium subgroup of Drosophila. Alpha- and beta-esterase expression was significantly decreased in LL when compared to LD and DD at both the generations and species. In all the light regimes, females were found to have significantly higher level of alpha- and beta-esterase expression than males. Flies were maintained under different light regimes showed difference in their expression patterns with respect to alpha- and beta-esterases. The present study showed that constant light conditions affect the expression of esterases in D. agumbensis and D. nagarholensis

BIRD FORAGING AND ITS ECONOMIC EFFECT IN THE PADDY FIELDS OF BANGALORE (INDIA)

Birds are often serious pests of rice. The small size of this cereal at all stages of its ripening makes it attractive for the small, seed-eating birds. Considerable damage also is inflicted during early stages of growth when germinating seedlings are depredated by grainivores, and several species of aquatic birds trample the fields in search of food. The migratory blackbirds (Agelaius species and others) eat various grains across the U.S.A. and Mexico, while huge numbers of red-billed weaver bird (Quelea quelea) account for grain losses up to 20% in several rice-growing African countries (Efferson, 1952). Although rice is the staple food for the majority of India, information available on bird damage to paddy is inadequate. Spotted munia (Hamid Ali et aI., 1976; Saha and Mukherjee, 1978; Verghese and Chakravarthy, 1981) and baya (Mathew, 1976; Hamid Ali et aI., 1976) are the recognized pests of rice. A host of insectivorous birds prey upon the abundant insect pests of rice. Studies on ecology of rice field birds and their foraging patterns will aid in formulating the best possible measures to prevent damage. Hence, in this preliminary study, data on the density and diversity of birds visiting a paddy field, their spatial and temporal distribution, feeding behavior, and foraging strategy were collected

Seasonality of suicidal behavior in Mysuru, Karnataka, India: a populace based analysis

Objectives: In India there are very few epidemiological studies that describe the association between suicides and physical factors, which underlie seasonal changes, particularly temperature. We investigated the role of temperature in suicidal behaviors and have analyzed whether the affiliation varies with gender and age in Mysuru, India between 2007 and 2016. Methods: Suicide data, categorized by Month of suicide, age, gender, and method of suicide were provided by 22 Karnataka state police stations. The data was subjected to chi-squared distribution test and the frequency of suicides at each seasons with respect to age and gender were analyzed. Results: A total of 4254 completed suicidal cases were obtained in the examined period. A clear seasonal pattern was observed, with suicidal frequencies being highest between February and May (40%) and lowest between June and January (10%) and the percentage of suicidal incidences in the age group of 21-40 is more (56.2%) compared to other age groups. Conclusion: This study shows that suicides followed a seasonal pattern, with a maximum peak in summer. We have observed that suicidal rates are high among males and this examination also reveals a higher rate of suicidal incidences among younger ones comparatively. Hence we speculate that seasonal changes in temperature account for variations in the number of suicides. Temperature, which increases the concentration of serotonin neurotransmission, may trigger increased impulsivity and promote suicidal behaviors, which require a further more research to clarify the role of temperature in triggering neurobiological changes in brain

Molecular phylogenetic analysis of a few Penaiedae species (Crustacea, Decapoda) using RAPD

Penaiedae species, Penaeus canaliculatus Penaeus indicus, Metapenaeus dobsoni, Metapenaeus monoceros, Parapenaeopsis stylifera, Parapenaeopsis longipes and Trachypenaeus curvirostris from Arabian Sea (Mangalore Coast, India), were genetically examined using RAPD markers. Ten selective primers provided distinct and consistent RAPD profiles in all the seven species. A considerable amount of polymorphism was detected at the interspecific as well as intraspecific levels with all ten primers. A total of 105 fragments were scored. Of these 10 fragments, were monomorphic bands shared by all species. Out of 105 fragments, 95 (90%) bands were polymorphic and shared by at least two species. There are also some fragments, which are highly species specific for a particular primer, which are not at all shared by other species. The range of dissimilarity index is from 0.392 the lowest one to 0.599 the highest one. The least 1-F value is between Metapenaeus dobsoni and Metapenaeus monoceros and the highest dissimilarity index between Penaeus canaliculatus and Trachypenaeus curvirostris

Eclosion behaviour of three species of<i style="mso-bidi-font-style:normal"> Drosophila</i> under different light regimes

660-664The daily patterning of animal behaviour is presumed to be due to changes in responsiveness to external stimuli, as a function of varying internal states which may be oscillating with a 24 h period. The endogenous circadian system functions to organize behaviour and physiology to adapt to and anticipate environmental changes in light, temperature, food and mate availability. Light is most important zeitgeber that influence circadian physiology of several insects. The present study is an attempt to understand the eclosion behaviour of Drosophila melanogaster (Oregon-K strain), Drosophila gangotrii and Drosophila jambulina under light/dark (LD), continuous light (LL), continuous dark (DD) conditions for 30 generations. The stocks were maintained at 20±1 °C with 75% RH. Eclosion behaviour was analyzed at 4 h intervals until complete emergence of flies. Result reveals that in all the species peak of eclosion was found at dawn and on subjective day. Intraspecies comparison shows that there was no significant difference in eclosion at different time point and generations under different light regimes. However, interspecies comparison shows significant difference for hours. The data from experiments showed altered rhythm in the form of phase advance and phase delay in eclosion at different light regimes suggesting the role of photoperiod in the physiology of organisms. </span