Corn rootworm, control

Harris CK, Chapman RA, Tolman JH, et al. 1988. A comparison of the persistence in a clay loam of single and repeated annual applications of seven granular insecticides used for corn rootworm control. J Environ Sci Health [B] 23 1-32. 

Field Evaluation of Chemical Rotations. During 1985-1988, experiments were conducted at the Univ. of 111. Northwest Illinois Agricultural Research and Development Center near Monmouth, Illinois. A single 2-acre field was used over the 4 years of research. The soil was a Muscatine silt loam and the slope was 2% (soil 69, Table I). The cropping history prior to 1985 was soybeans, 1980-82 wheat, 1983 corn, 1984. No soil insecticide had been used for at least three years prior to 1985. Chlorpyrifos (Lorsban 4E) was used for adult corn rootworm control during 1984. 

EL-499 is a potent uncoupler of oxidative phosphorylation in vitro and exhibits hydrolytic lability under conditions involving either heating with base in solution or incubation in soil. The small differences observed in acute toxicity with isomers (1) and (2) and a wide variety of alpha-branched perfluorinated alkyl substituents reported earlier (8) further indicates that there exists only a generalized lipophilic structural requirement for activity/ ie. alpha-branching. Indeed, if there is an uncoupler binding site, (17/18) it is expected that molecular recognition is associated principally with the aniline ring and its substituents. Under more severe hydrolytic conditions, differentiation of even the alpha-branched perfluorinated carboxanilides is observed, which manifests itself in differential residual corn rootworm control. 

Al-Deeb, M.A., G.E. Wilde, J.M. Blair, and T.C. Todd. 2003. Effect of Bt corn for corn rootworm control on non-target soil microarthropods and nematodes. Environ. Entomol. 32 859-865. 

Higgins, L. and D. Wright. 2003. Evaluation of the Impact of Corn Rootworm Control Strategies on Non-Target Arthropods. Project Number PHI/2001/020. Unpublished study prepared by Pioneer Hi-Bred International, Inc. 85 p. 

The peak period for the use of aldrin and dieldrin was between the late 1960s and the early 1970s throughout various parts of the world (WHO, 1989). The use pattern of aldrin and dieldrin are quite similar. They act as effective contact and stomach poisons for insects. They are used to control soil insects (e.g. grasshoppers and corn rootworm), and protect crops and wooden structures from termites (WHO, 1989). The production of aldrin and dieldrin has decreased since the early 1960s. In the United States, the peak use of aldrin from 19 million pounds in 1966 decreased to 10.5 million pounds in 1970 (USEPA, 1980). During this same period (1966-1970), annual dieldrin use dropped from 1 million to 670,000 pounds. These decreases were primarily due to increased insect resistance to the aldrin and dieldrin, and to the development and availability of more effective and environmentally friendly pesticides (USEPA, 1980). 

Other plant-feeding insects, such as the cabbage looper, have piled one resistance upon another, so that we must look to pheromones and chemosterilants for their control. The western corn rootworm has now joined the onion maggot in going OP-resistant. Resistance problems on pests of rice in Japan are becoming as severe as those on cotton in the Americas. 

Trimethacarb is a stomach poison insecticide with some contact activity used for controlling corn rootworm larvae and other insects, and mollusk pests. Its oral LD30 in rats is 125 mg/kg. 

This report summarizes the synthesis, insecticidal activity, and field performances of some S cyanoalkyl phosphorodithioates related to terbufos. Replacement of one of the methyl groups of terbufos with a nitrile yielded an insecticide more active than terbufos but lacking its soil persistence. However, addition of a methyl group to the carbon between the two sulfur atoms of this S-cyanoalkyl phosphorodithioate produced a compound that was almost as active as Terbufos as an insecticide and gave economic control of corn rootworms at 1 lb/A. 

Will the insect spectra be changed compared to terbufos which only controls corn rootworms ... 

Despite their weaker performance In the laboratory Dlabrotlca jar test when compared to terbufos, two of the best compounds of Table 4 were taken to the Midwest for evaluation as soil Insecticides for control of corn rootworm. The compounds were placed In the soil at planting as a band application at 1 lb/A. During late July and early August the roots were evaluated for corn rootworms damage. A summary of those tests Is collected In Table 6 along with terbufos as a standard. 

This is a review of synthetic efforts made at these laboratories in recent years. Stereoisomers of sex pheromones of various insect species were synthesized in order to facilitate identification and permit more thorough evaluation of their potential in insect control programs. Syntheses are described for pheromones of the stable fly, tsetse fly, southern and western corn rootworms, and the Mediterranean fruit fly attractant, trimed-lure. In each instance centers of asymmetry were generated that made use of diastereomer formation using readily available (R)- and (S)-a-methyl-benzylamine. Resolutions were achieved either by preparative HPLC, or fractional crystallization of amides. The latter technique was rendered synthetically useful for the preparation of configurationally pure acids by virtue of transformations wrought upon the amides that made them subject to cleavage under very mild conditions. 

Control of corn rootworm was obtained in a unique way by the spraying of tiny plastic tubes dropped by plane or helicopter. The tubes were coated by a three-part mixture consisting of a synthetic sex pheromone to lure the male beetles, compounds from the squash and cucumber family to encourage feeding, and a minute amount of an appropriate insecticide. 

Aldrin from Corn. The most important use of aldrin is as a soil insecticide under corn. Here it is usually incorporated in the soil at application rates of 1-2 lb./acre to a depth of 3-4 inches. In muck soils the rate may be as high as 5 lb./acre. It is used to control the com rootworm and wireworm complexes plus other soil insects. 

Because rootworm insecticides are most commonly applied at planting, 4-8 weeks prior to rootworm egg hatch, it was early recognized that the inherently rapid degradation rate of some of these insecticides precluded their effective use (5). However, most provided effective control without the undesirable environmental impact of the chlorinated hydrocarbons. By 1973 roughly 20-30 million acres of midwest corn were treated annually with soil insecticides (6), and corn had become the leading crop for use of soil Insecticides. 

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