Insect resistance genes

Bell, H. A., Down, R.E., Fitches, E.C., Edwards, J.P. and Gatehouse, A.M.R. (2003). Impact of genetically modified potato expressing plant derived insect resistance genes on the predatory bug, Podisus maculiventris (Heteroptera Pentatomidae). Biocontrol Science and Technology 13 729-741. 

Insect-resistant transgenic crops 271 Table 13.1 Classes of insect resistance genes expressed in transgenic crop plants... 

V.A. (1990). Additive protective effects of different plant-derived insect resistance genes in transgenic tobacco plants. Crop Prot. 9, 351-354. 

Factual knowledge is the knowledge of what actually happens (quantitative data or empirical, observed data). Examples gene flow species by species or region by region facts about insect resistance in agriculture. 

Different lines, each with Insect resistance, may possess different ratios of antibiotic compounds. Thus, It may be possible to Increase resistance by crossing lines where each contributes genes for biosynthesis of different antibiotic compounds. The tobacco budworm was selected for study In preference to the cotton bollworm because It Is easier to rear and use In the laboratory, Is more resistant to Insecticides In the field, and It Is approximately as susceptible to cotton constituents Incorporated In laboratory diets (14). This present study was carried out to Identify and analyze for cotton constituents that were toxic In laboratory feeding tests, and to determine whether there were positive correlations of their content In leaves and/or other tissue with field resistance. From this Information, the generation of lines with multiple factors for resistance could be Initiated. 

Recall in our discussion of routes of biotransformation we considered species differences using malathion as an example. Insects convert this compound to its toxic oxidation product more quickly than they detoxify it by hydrolysis. Humans do the conversions in the opposite priority. However, the insects which might be different from the general population and perform detoxification reactions at a faster rate would survive pesticide application and their "resistant" genes would be selectively passed on to the next generations. 

Ashok M., Turner C. and Wilson T. G. (1998) Insect juvenile hormone resistance gene homology with the bHLH-PAS family of transcriptional regulators. Proc. Natl. Acad. 

Breeders have selected celery with relatively high amounts of psoralens because farmers prefer to grow insect resistant plants and consumers prefer to buy undamaged produce. Unfortunately, workers who harvest such celery sometimes develop a severe skin rash (NAS 2004), an unintended consequence of this conventional breeding. It is possible that if the gene encoding the toxic protein had been cloned and studied before being introduced into the new varieties, farm workers would have learned of the harmful effects before exposure. 

Resistance to insecticides in insects and mites is preadaptive i.e., the genes controlling the resistance mechanism are already present in very low frequencies in the population prior to any use of insecticides. Therefore, the resistant genes are mutants from some earlier era in the insect s history, or were selected by other toxicants in its earlier environment, and... 

Pyrethroids are widely used to control many agriculturally and medically important insect pests. Due to intensive use of pyrethroids in pest control, many pest populations have developed resistance to these compounds. One major mechanism of pyrethroid resistance, conferred by the knock down resistance gene (Mr), is reduced target site (sodium channel) sensitivity to DDT and pyrethroids. Studies on the molecular basis of Mr and Mr-type resistance in various insects are enhancing our understanding of the structure and function of insect sodium channels and the molecular interaction between insect sodium channels and pyrethroids. In this chapter, I will review recent advances in... 

Zhang, Z.-Y., Ober, J.A. and Kliebenstein, D.J. (2006) The gene controlling the quantitative trait locus Epithiospecifier modifier 1 alters glucosinolate hydrolysis and insect resistance in Arabidopsis. Plant Cell, 18,1524—36. 

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