Microbial infection, insect

St. Leger, R. J. (1991). Integument as a barrier to microbial infections. In Physiology of the Insect Epidermis, ed. K. Binnington and A. Retnakaran. East Melbourne, Victoria, Australia CSIRO Publications, pp. 284-306. 

Wink, M. (2007) Importance of plant secondary metabolites for protection against insects and microbial infections, in Advances in Phytomedicine, Vol. 3 Naturally Occurring Bioactive Compounds (eds C. Rai and M. Carpinella). Elsevier, Amsterdam, pp. 251-68. 

The parasites which cause plant diseases may be spread by wind, rain, insects, birds, snails, slugs, and earthworms, transplant soil, nursery grafts, vegetative propagation (especially in strawberries, potatoes, and many flowers and ornamentals), contaminated equipment and tools, infected seed stock, pollen, dust storms, irrigation water, and people. Figure 3.8 illustrates the effects of microbial infection of various fruit trees. 

The cuticular waxes of insect species may contain the following chemical classes hydrocarbons, fatty acids, alcohols, triacylglycerols and wax esters (Golgbiowski et al., 2011 Nelson Blomquist, 1995). The waxes of some species also contain aldehydes, ketones, esters and sterols. The wax compositions of insects can vary depending on stage, sex, age, and their position in the colony hierarchy. Cuticular waxes can also vary within species as a response to living conditions such as temperature, dryness and available food. The major function of insect waxes is protection against desiccation, but they also prevent microbial infections, affect the adsorption of chemicals and play a role in chemical communication... 

Studies of the potential costs associated with xenobiotic resistance in the absence of the selective agent can suffer from several confounding experimental factors. First, fitness costs associated with strains in which resistance has been repeatedly selected for in the laboratory are unlikely to represent fitness costs associated with resistance mechanisms found in the field. Second, the resistant and susceptible strains compared are also often genetically unrelated and any observed costs may therefore be independent of the resistance trait itself Third, when insects are used they are often not checked for the presence of microbial pathogens, such as Wolhachia, which can influence the outcome of crosses between infected and uninfected strains. 

In Egypt, mixture from roots of Amaryllis belladonna and Cltvia miniata were used to treat and prevent infection of wounds such as insect and snake bites. The anti-microbial activities are achieved by virtue of eertain types of AAs namely lycorine, homolycorine, haemanthamine and tazettine present in the root mixture [10, 15, 19]. 

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