Role of Kairomones in The Management of Sal Borer (Hoplocerambyx Spinicornis) Population

Hoplocerambyx spinicornis is a major pest of Sal which causes extensive damage to the Sal trees. As regard to the chemical control there is any likelihood of chemical control. The grub bores very deep into the heartwood and lodges itself inside chambers and galleries. Thus the present study deals with the multidisciplinary approach like the use of biocontrol agents (natural enemies), testing of kairomones, use of olfactrometer and the use of variously designed traps to manage the borers’ population. Kairomone is the alternate chemical attractant which contain flavanoids, terpenoids and amine compounds. Such methods avoid felling of trees which are used in controlling pest population since decades. Above methods being eco friendly and environmentally sound could manage the pest population up to certain economic threshold level.

Diversity and population dynamic of Tabanidae (Diptera) in the cerrado-pantanal ecotone

Tabanid (Diptera) species are associated with the mechanical transmission of several pathogens to both domestic and wild animals around the world. The aim of this study was to evaluate the diversity, abundance, and seasonal dynamic of tabanids in the Cerrado-Pantanal ecotone in Miranda, state of Mato Grosso do Sul, Brazil. Tabanids were collected once a month, from June 2001 to May 2003, for seven consecutive days per collection, using canopy and nzi type traps baited with a chemical attractant (1-octen-3-ol). A total of 6,492 individuals from 39 species and 18 genera was collected, which increases from 25 to 34 the number of tabanid species reported for the studied region. Tabanus occidentalis Linnaeus, 1758 (62.21%) was the most abundant species throughout the collection period, followed by Lepiselaga crassipes (Fabricius, 1805) (7.19%) and Tabanus sorbillans Wiedemann, 1828 (5.68%). The peak of the tabanid population was reached during the rainy season, which is the period of the highest potential risk of mechanical transmission of pathogens by these insects in the studied region.

Exploiting the Synergistic Effect of Kairomones and Light-Emitting Diodes on the Attraction of Phlebotomine Sand Flies to Light Traps in Brazil

The synergistic effect of light-emitting diodes (LEDs) and kairomones on the attraction of sand flies to light traps was evaluated. Octenol and lactic acid were used as chemical attractants. Green LEDs and the incandescent lamps were used as light attractants. Five CDC-type light traps with the respective combination of attractants (incandescent lamp, incandescent lamp + chemical attractant, green LED, green LED + chemical attractant, and chemical attractant alone [without light]) were set between 18:00 and 06:00 following a Latin square design. A total of 6,536 sand flies and 16 species were collected. The most frequent species collected was Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera, Psychodidae) accounting for 43.21% of all individuals. Order of success (mean, SD) of lactic acid attractant fly capture was as follows: LED + lactic acid (36.83 ± 4.74), LED alone (34.87 ± 4.61), incandescent lamp + lactic acid (22.80 ± 3.19), incandescent lamp alone (12.67 ± 2.03), and lactic acid (0.46 ± 0.13). Order of success of octenol attractant fly capture was as follows: LED + octenol (37.23 ± 5.61), LED alone (35.77 ± 5.69), incandescent lamp + octenol (18.63 ± 3.28), incandescent lamp alone (14.67 ± 2.86), and octenol alone (1.80 ± 0.65). With exception of lactic acid + incandescent light, chemical synergists played no part in significantly increasing light trap capture of phlebotomine sand flies. However, the use of LEDs, with or without such attractants, provided significantly higher capture compared to the incandescent lamp with or without such chemicals, showing that LEDs are suitable and efficient light sources for surveillance and monitoring of phlebotomine sand flies in Brazil.

A System for Harvesting Eggs from the Pink-Spotted Lady Beetle

We describe a system for harvesting eggs from a predatory insect, the pink-spotted lady beetle,Coleomegilla maculataDe Geer (Coleoptera: Coccinellidae). Adult beetles placed in square, transparent containers that included oviposition substrates hanging from the top of the cage deposited eggs on the materials provided. We harvested eggs from these substrates in quantities sufficient for either destructive sampling or synchronous development of larvae. We evaluated effects of crowding inside cages; effects of a chemical attractant on oviposition behavior; egg cannibalism. Females preferred a textured surface rather than a smooth, waxy one for laying eggs. Crowding inhibited oviposition of beetles. Presence of a chemical attractant (methyl salicylate) did not significantly improve oviposition. This paper describes an inexpensive system for harvesting eggs fromC. maculata. Refinement of this system should improve oviposition and reduce cannibalism.

THE SET OF CONCENTRATION FOR SOME HYPERBOLIC MODELS OF CHEMOTAXIS

Chemotaxis models are typically able to develop blow-up in finite times. For some specific models, we obtain some estimates on the set of concentration of cells (defined roughly as the points where the density of cells is infinite with a non-vanishing mass). More precisely we consider models without diffusion for which the cells' velocity decreases if the concentration of the chemical attractant becomes too large. We are able to give a lower bound on the Hausdorff dimension of the concentration set, one in the "best" situation where the velocity exactly vanishes for too large concentrations of attractant. This in particular implies that the solution may not form any Dirac mass.