Role in insect resistance

I suggest that phytoalexins play an important role in insect resistance by plants. This role of phytoalexins and phytoalexin elicitation now should be studied further and tested under field conditions. 

As many of the same types of diterpenes play an active role in the resistance of other plants to insect attack (see above), it is interesting to investigate the role of diterpenes in Solidago and its interactions with insects. Solidago has the advantage that the behavior and the ecology of many of the associated insects are well known (80). 

Quinolizidine alkaloids, pure or in mixtures of plant extract, can be used to protect plants against noxious insects. Scientific data has shown that quinolizidine alkaloids play a role in the resistance of some lupine varieties to the pea... 

The use of glucosinolates as bases of resistance against insects seems consistent with their role in disease resistance (39). However, with crops possessing high levels of cyanogens or glucosinolates to effect resistance, the value of these crop plants as food for humans, livestock, and/or poultry is often greatly depreciated because of the toxicity of the end-products (35,36 4Q)-... 

Resistance to py rethroids can also be in part attributed to reduced penetration in insects. Ahmad et al. (2006) found that delayed cuticular penetration played an important role in deltamethrin resistance in Chinese and Parkinson strains of the cotton bollworm, Helicov-erpa armigera. The half-time for applied deltamethrin was 1 hr for the susceptible strain and 6 hr for both of the resistant strains. 

Progress has also been made in molecular studies of cytochrome P-450 monooxygenases that are known to play an important role in insecticide resistance. The cytochrome P-450 gene from the house fly has been cloned, which should enable studies of the genetic regulation of insect cytochrome P-450 and further elucidation of its role in insecticide resistance (fil)-... 

Severson, R.E, A.W. Johnson, and D.M. Jackson Cuticular constituents of tobacco Factors affecting then-production and their role in insect and disease resistance and smoke quality Recent Adv. Tob. Sci. 11 (1985) 105-174. 

Baxter, G. D, and Barker, S. C, (199H). Acetylcholinesterase cDNA ol the cattle tick, Boophilus mk mplits Characicfizaiion and role in nrganophosphaie resistance. Insect, Biochem. Mol. Biol. 28,5S1-5S9. 

The role of insect-resistant transgenic crops in agriculture... 

Potential effects of transgene products on pollinating insects such as honey bees and bumble bees, which play a major role in seed production and fruit set of many crops, are of great importance. They feed on pollen and nectar and therefore it is necessary to determine the toxicity of the entomotoxin expressed in insect-resistant transgenic plants both in the short and long term. To date such studies with honey bees have been performed predominantly using artificial diets where the entomotoxins are... 

Quinolizidine alkaloids, pure or in mixtures of plant extract, can be used to protect plants against noxious insects. Scientific data have shown that quinolizidine alkaloids play a role in the resistance of some lupine varieties to the pea aphid (Acyrthosiphon pisum Harris) due to their ability to inhibit the development of this pest population. Evidence also points out that alkaloid extracts have an important influence on the feeding and development of larvae and on potato beetle mortality. Researchers concluded that the toxicity and restricted larval development was correlated with alkaloid content. In this research, the strongest action of the extract contained 1.6-3.3% alkaloids. Spraying potatoes with lupine extract seems to be... 

Hedin, P.A. and Waage, S.K., Roles of flavonoids in plant resistance to insects, in Plant Flavonoids in Biology and Medicine Biochemical, Pharmacological and Structure Activity Relationship, Cody, V., Middleton, E., and Harbome, J.B., Eds., Alan Liss, New York, 1986, 87. 

The Role of Natural Photosensitizers in Plant Resistance to Insects... 

The behavior of Insects In selecting a host plant for food and shelter is affected by a wide array of physical and chemical stimuli. Chemicals that play a role in resistance mechanisms may interfere with an Insect s orientation, inhibit feeding, or deter ovipositlon. Most of the known mechanisms of resistance involve feeding deterrents, but the most vulnerable phase of the Insect life cycle may prove to be ovipositlon. Environmental factors may influence the ability... 

DDT-dehydrochlorinase is an enzyme that occurs in both mammals and insects and has been studied most intensively in DDT-resistant houseflies. It catalyzes the dehydrochlorination of DDT to DDE and occurs in the soluble fraction of tissue homogenates. Although the reaction requires glutathione, it apparently serves in a catalytic role... 

Despite the relatively low percentage content of extractives (Table II), they very often influence wood properties and thus play a role in utilization. Advantages accrue from the presence of colored and volatile extractives which provide esthetic values. Some of the phenolic compounds provide resistance to insect and fungal attack. Other extractives provide useful products. From tall oil, products such as turpentine, rosin and fatty acids are produced. In addition, tannins, camphor, gum arabic, natural rubber and flavonoids are some of the many products from extractives. 

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