VARIABLE RESPONSE OF THREE MORPHOTYPES OF TECOMELLA UNDULATA (SM.) SEEM TOWARDS HUMAN PATHOGENIC BACTERIA

Objective: Medicinal Tree Tecomella undulata [Sm.] Seem belonging to family Bignoniaceae has three distinct morphotypes. Present study was undertaken to assess antimicrobial potential of the three morphotypes of Tecomella undulata against human pathogenic bacteria to select suitable morphotype for medicinal use.Methods: Disc diffusion method was used to test and compare the antimicrobial activity exhibited by 13 populations belonging to three morphotypes of this tree against five human pathogenic bacteria i. e. Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus.Results: Methanol and acetone extract of bark of the tree showed considerable activity against all the five bacteria tested. Differences were observed in the activity not only between the morphotypes but also within the morphotypes against the bacteria tested. Out of the three morpho types yellow morphotypes showed the highest antimicrobial action against all the five bacteria which were comparable to standard antibiotic Chloramphenicol. The trend in antibacterial activity observed was yellow>red>orange in acetone extract and yellow>orange>red in methanol extract towards all microbes except against bacillus bacteria where it was yellow>orange>red [acetone] and orange>yellow>red [methanol].Conclusion: The experimental results of the present study revealed that Tecomella undulata plants show great intraspecific variability in their antibacterial potential. Hence there is need to evaluate germplasm to select superior genotype for medicinal, multiplication, conservation or plantation purpose.Â

Neonicotinoid Insecticides and Their Impacts on Bees: A Systematic Review of Research Approaches and Identification of Knowledge Gaps

It has been suggested that the widespread use of neonicotinoid insecticides threatens bees, but research on this topic has been surrounded by controversy. In order to synthesize which research approaches have been used to examine the effect of neonicotinoids on bees and to identify knowledge gaps, we systematically reviewed research on this subject that was available on the Web of Science and PubMed in June 2015. Most of the 216 primary research studies were conducted in Europe or North America (82%), involved the neonicotinoid imidacloprid (78%), and concerned the western honey bee Apis mellifera (75%). Thus, little seems to be known about neonicotinoids and bees in areas outside Europe and North America. Furthermore, because there is considerable variation in ecological traits among bee taxa, studies on honey bees are not likely to fully predict impacts of neonicotinoids on other species. Studies on crops were dominated by seed-treated maize, oilseed rape (canola) and sunflower, whereas less is known about potential side effects on bees from the use of other application methods on insect pollinated fruit and vegetable crops, or on lawns and ornamental plants. Laboratory approaches were most common, and we suggest that their capability to infer real-world consequences are improved when combined with information from field studies about realistic exposures to neonicotinoids. Studies using field approaches often examined only bee exposure to neonicotinoids and more field studies are needed that measure impacts of exposure. Most studies measured effects on individual bees. We suggest that effects on the individual bee should be linked to both mechanisms at the sub-individual level and also to the consequences for the colony and wider bee populations. As bees are increasingly facing multiple interacting pressures future research needs to clarify the role of neonicotinoids in relative to other drivers of bee declines