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Objectives of the current work were to investigate the role of photoperiod and melatonin in the alteration of immune responses in a reptilian species. Animals were kept on a regimen of short or long days. Blood was obtained and leucocytes were isolated to study various innate immune responses. Lymphocytes were separated from blood by density gradient centrifugation and were used to study proliferation. Respiratory burst activity was measured through nitrobluetetrazolium reduction assay while nitric oxide production by leucocytes was assayed by nitrite assay. Lymphocytes were isolated and used to study proliferation with and without B and T cell mitogens. Photoperiodic manipulation acted differentially on leucocyte counts. Nitrite release was increased while superoxide production was decreased in cultures obtained from the snakes kept on the short day regimen. Significant enhancement of mitogen induced lymphocyte proliferation was observed in cultures from the animals kept in either long or short days compared to cultures from the animals kept in natural ambient day length. Use of in vitro melatonin showed that lymphocytes from the animals, kept in long days, were more reactive. Photoperiod induces changes in immune status which may permit adaptive functional responses in order to maintain seasonal energetic budgets of the animals. Physiological responses (like elevated immune status) are energetically expensive, therefore, animals have evolved a strategy to reduce immune functions at times when energy is invested in reproductive activities. Natrix piscator breeds from September to December and elevated pineal hormone in winter suppresses reproduction while immunity is stimulated.In freshwater environments the rotifer group may be divided into microphagous and raptorial species regarding their feeding patterns, and such guilds differently interact with other community components. Here, we analyzed the influence of cladocerans, cyclopoid nauplii, temperature, food resources and an exotic species on rotifer guilds, based on weekly samplings for 1 year. We have identified rotifer species and their trophi types in order to separate them into the raptorial and microphagous functional groups. The ratio raptorialmicrophagous rotifers (Guild ratio, GR) was used in interaction analyses with cladocerans, nauplii, temperature, food resources and the exotic species Kellicottia bostoniensis. Correlations between total rotifers and food (phytoplankton carbon) and temperature were negative and significant, therefore, these factors did not lead to the increase of rotifer community. On the other hand, microphagous rotifers had opposing relation to cladoceran densities, as GR values showed that they became predominant when cladoceran populations declined. The use of density-based GR was adequate, with similar results compared to biomass-based studies regarding interactions with other organisms. Furthermore, we have found no invasive characteristics for the exotic microphagous rotifer, Kellicottia bostoniensis, and it seems to be outcompeted by the native microphagous species.The whitebacked planthopper (WBPH), has become a devastating pest for rice crops, causes serious yield losses each year, and urgently needs biological control. Here, we developed a WBPH-resistant rice cultivar by overexpressing the OsF3H gene. A genetic functional analysis of the OsF3H gene confirmed its role in facilitating flavonoid contents and have indicated that the expression of the OsF3H gene is involved in regulation of the downstream genes (OsDFR and OsFLS) of the flavonoid pathway and genes (OsSLR1 and OsWRKY13) involved in other physiological pathways. OxF3H (OsF3H transgenic) plants accumulated significant amounts of the flavonols kaempferol (Kr) and quercetin (Qu) and the anthocyanins delphinidin and cyanidin, compared to the wild type, in response to the stress induced by WBPH. Similarly, OsF3H-related proteins were significantly expressed in OxF3H lines after WBPH infestation. The present study, indicated that the regulation of JA in OxF3H plants was suppressed due the overexpression of the OsF3H gene, which induced the expression of downstream genes related to anthocyanin. Similarly, the OsWRKY13 transcriptional factor was significantly suppressed in OxF3H plants during WBPH infestation. Exogenous application of Kr and Qu increased the survival rates of susceptible TN1 lines in response to WBPH, while decreased the survival rate of first instar WBPHs, indicating that both flavonols exhibit pesticide activity. Phenotypic demonstration also affirms that OxF3H plants show strong resistance to WBPH compared with wild type. Collectively, our result suggested that OsF3H overexpression led to the up-regulation of defense related genes and enhanced rice resistance to WBPH infestation.Dogs live in 45% of households, integrated into various human groups in various societies. This is certainly not true for wolves. We suggest that dogs' increased tractability (meant as individual dogs being easier to control, handle and direct by humans, in contrast to trainability defined as performance increase due to training) makes a crucial contribution to this fundamental difference. In this study, we assessed the development of tractability in hand-raised wolves and similarly raised dogs. We combined a variety of behavioural tests fetching, calling, obeying a sit signal, hair brushing and walking in a muzzle. Wolf (N = 16) and dog (N = 11) pups were tested repeatedly, between the ages of 3-24 weeks. In addition to hand-raised wolves and dogs, we also tested mother-raised family dogs (N = 12) for fetching and calling. Our results show that despite intensive socialization, wolves remained less tractable than dogs, especially in contexts involving access to a resource. Dogs' tractability appeared to be less context dependent, as they followed human initiation of action in more contexts than wolves. We found no evidence that different rearing conditions (i.e. intensive socialization vs. mother rearing) would affect tractability in dogs. ABT-263 molecular weight This suggests that during domestication dogs might have been selected for increased tractability, although based on the current data we cannot exclude that the differential speed of development of dogs and wolves or the earlier relocation of wolves to live as a group explains some of the differences we found.