Rootworm

The com rootworms Diabrotica barberi and D. virgijera were controUed in the U.S. com belt from 1954 to 1964 by soil appHcations of heptachlor and aldrin. A resistant race of the western com rootworm D. virgijera was first characterized in southeastern Nebraska in 1961 and spread rapidly throughout the entire com belt. Successive introductions of carbamate and organophosphate soil insecticides have increased the cost of com rootworm control from... 

The Diabrotica spp. com rootworm beetles are specifically attracted to a variety of plant-produced phenylpropanoids, eg, ( )-cinnamaldehyde [14371-10-9] for the southern com rootworm D. undecimpunctata howardr, ( )-cinnamyl alcohol [4407-36-7] for the northern com rootworm D. barberi and indole [120-72-9] for the western com rootworm, D. virgifera virgifera. Especially powerflil lures for these rootworm beetles are 2-(4-methoxyphenyl)ethanol for the northern com rootworm and 4-methoxycinnamaldehyde [71277-11-7] (177) for the western com bootworm. 

Meinke, LJ USDA To study the influence of methyl parathion on western corn rootworm behavior and population dynamics. 

Meinke, LJ USDA Western corn rootworm resistance to methyl parathion-development of resistance management strategies... 

Wright, RJ USDA To document the extent of adult corn rootworm beetles resistence to methyl parathion throughout Nebraska. 

The compounds that we will consider here, in contrast, serve quite specific needs of various organisms, and for this reason we will call them special chemical compounds. Different species may employ the same special compound, in some cases for the same purpose and in other cases for different ends. For example, the carbon dioxide arising from the respiration of a crowd of ants is an aggregation signal that invites solitary ants to join their nestmates. Corn rootworms, however, use the carbon dioxide that living corn roots emit into the soil as a signal, leading them to their food. Different species may also employ diverse compounds for essentially the same purpose. Various ant species mark their food trails with different chemicals to keep their food sources secret from one another. 

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. 

Symptoms Southern corn rootworms feed on corn roots, often killing young plants and weakening older ones. Striped cucumber beetle larvae feed on the roots of squash-family plants only, killing or stunting the plants. Adults of both species feed on leaves, stems, flowers, and fruit of squashes and other crops. 

Because of their similar life cycles, habits, damage to corn, and apparent resistance to conventional corn rootworm insecticides, we could expect both the PSB and HBV to increase their densities and/or range throughout the Midwest much as the PSB has (9,12). These concerns are evident in the 1985 establishment of a multistate regional research effort entitled "Impact of integrated crop management practices on European corn borer and related stalk boring insects". 

Lin, S. and Mullin, C.A., Lipid, polyamide and flavonol phagostimulants for the adult Western com rootworm from sunflower pollen, J. Agric. Food Chem., 47, 1223, 1999. 

Insecticides Vetch aphid (Megoura viciae) bollworm (Helicoverpa zea) army worm (Spodoptera littoralis) diamondback moth (Plutella xylostella) mustard beetle (Phaedon cochleariae) corn rootworm (Diabrotica undecimpunctata) whitefly Bemisia tabaci) red spider mite (Tetranychus urticae). 

Jaspamide (17), previously mentioned in Section 17.3, is a modified peptide isolated from a Jaspis sponge. Jaspamide shows insecticidal activity against Heliothis virescens with an LCS0 of 4 ppm, as compared to 1 ppm for azadirachtin. Jaspamide (17), showed more than 72% mortality at 100 ppm to both southern com rootworm and tobacco budworm. Iso-domoic acids A (40), B, and C are novel amino acids from the red alga Chondria armata. They... 

The macrolide halichondramide (3)62 showed more than 75% mortality (100 ppm) against newly hatched larvae of the southern com rootworm, Diabrotica undecimpunctata howardi, and the tobacco budworm, Heliothis virescens.44 The dimeric macrolides swinholide A and... 

We mentioned earlier the in vitro antimalarial activity of halichondramide and swin-holide A.22 The initial testing of compounds 3 to 5 displayed 75 to 100% mortality of both corn rootworm and tobacco budworm. On titration, they displayed an LCS0 range of 10 to 100 ppm, and induced 30, 85, and 30% corn rootworm larval stunting, respectively. Both halichondramide and swinholide A caused 85% tobacco budworm larval stunting. The significant insecticidal activity of these compounds (3 to 5) indicates that further QSAR studies of the compounds would be valuable. These compounds illustrate the necessity to examine various marine macrolides as potential prototype insecticides. 

The homochiral f -branched carboxylic acids (13 or enf-13 Table 1) have been used for the synthesis of a variety of natural products21 such as California red scale pheromone,14 a-skytanthine,22 the southern com rootworm pheromone,15 and norpectinatone.16 Pure (5)-3-trichloromethylbutyric acid (a structural subunit of some sponge metabolites) was prepared via conjugate addition of ClaCMgCl to the chiral cro-tonate (16) followed by hydrolysis (Scheme S).23... 

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). 

The entire subject has been reviewed in detail several times.32,56,57,65 Recently, a new adsorptive method for the isolation of DIMBOA has been reported.49 The impact of benzoxazinoids on the western corn rootworm (Diabrotica virgifera LeConte) development has been studied.17 The allocation of a hydroxamic acid and biomass during vegetative development of rye has been investigated.27 Effects of benzoxazinoids from maize on survival and fecundity of aphids have been explored.13 DIMBOA concentrations have been measured in various isolines of wheat and corresponding plant introduction lines.55 The variation of the content of several benzoxazinoids in relation to the age and plant organ has been determined in maize plants.12... 

Davis, C. S., Ni, X. Z., Quisenberry, S. S. and Foster, J. E. 2000. Identification and quantification of hydroxamic acids in maize seedling root tissue and impact on western corn rootworm (Coleoptera Chrysomelidae) larval development. J. Econ. Entomol. 93, 989-992... 

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. 

It should be clear to us that the development of resistance is always to be expected to any insecticide we may choose to apply, but it is not inevitable. DDT stayed effective against the European corn borer for at least 15 years (Table VIII) and there are several other examples, including diazinon and the western corn rootworm in Nebraska. Some of the species of beneficial insects which formerly suffered from insecticide damage, such as braconid parasites, lady beetles, mayfly nymphs and honeybees, have now developed certain tolerances, while several of the Phytoseiid mites which feed on the plant-feeding spider mites are becoming as resistant as their prey to OP s and carbamates. 

W. Spruce Budworm W. Corn Rootworm mexacarbate diazinon Idaho Neb. 1963-73 14 gen 5... 

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