Tobacco bud worm

In some resistant strains, both types of resistance mechanism have been shown to operate against the same insecticide. Thus, the PEG87 strain of the tobacco bud worm (Heliothis virescens) is resistant to pyrethroids on account of both a highly active form of cytochrome P450 and an insensitive form of the sodium channel (Table 4.3 and McCaffery 1998). 

With the introduction of the carbamate insecticides in 1956, resistance to carbaryl appeared between 1963 and 1966 in an orchard leafroller in New Zealand, in the cotton leafworm (Spodoptera) of Egypt, and in Heliothis virescens (the so-called tobacco bud-worm) on American cotton (Table VI). Resistance developed to OP compounds had already given some cross-tolerance to carbamates... 

Anthocyanidins may also be important factors - with other flavonoids - in the resistance of plants to insect attack. Thus, the complete cyanidin 3-/3-glucoside (2)(0 Scheme 2) and not only the aglycon itself was shown to protect cotton leaves against the feeding of tobacco bud-worm [1]. 

A new member of the tartrolon series of macrodiolides, tartrolon C (17), was isolated from a Streptomyces species on the basis of its insecticidal activity [56]. The producing organism was isolated in 1990 from a soil sample collected near Braunschweig, Germany. Tartrolon C was active on the beet army worm and tobacco bud worm, with minimum emergent larvicide concentration of 125 ppm on both insects, approximately 40 x and 310 x less active than a standard of spinosyn A. 

Pyrethrins and PBO in combination with methoprene showed lOO ft control of feline fleas 35 days after treatment, with a satisfactory residual effect up to 2 months (Donahue, 1992). In addition (here is evidence that PBO is an 1GR in its own right. In a laboratory study PBO added lo three major cotton plant al 1 Biochemical s in the diet of tobacco bud worm larvae significantly decreased the growth rate of the 5-day-old larvae, and was found to be toxic to the 1- and 3-day-old larvae (Hey din t i u/.. 1988). 

Heydin, P A,. Parrott, W.L., Jenkins, J.N., Mulrocn, J,b. and Menn, J.J. (19881. Elucidating mechanisms of tobacco bud worm resistance io alleloehemieals by dietary tests with inseuicitie synergists. Panic. Siocfienr. Physiol. 32. 55-61. 

Another approach is to breed plants with large amounts of antifeedant in them. Breeders have succeeded in producing cotton containing high levels of gossypol in the leaves but not in the seeds.141 This deters the tobacco bud-worm (Heliothis virescens) while still allowing the seeds to be used as a source of edible cottonseed oil. 

B.A. Bierl-Leonhardt, J.R. Plimmer, A.N. Sparks, N. Primiani, O.L. Chapman, G. Lepone, and G.H. Lee Sex Pheromone Chemistry of the Female Tobacco Bud-worm Moth Heliothis virescens. J. Chem. Ecol. 6,177-183 (1980). 

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