Sap beetles

Attractive Compounds. The male-produced pheromones of sap beetles, known so far, show the rather stereotypic structures 125-147 (Scheme 15) methyl- and ethyl-branched hydrocarbons with three or four (T)-configured conjugated double bonds [4]. Up to now, 23 compounds could be identified, forming species specific mixtures. Major components in the bouquets are (2E,4E,6E)-5-ethyl-3-methyl-2,4,6-nonatriene, 128, in Carpophilus davidsoni [268] as well as in C.freemani [269], (2 ,4 ,6 )-4,6-dimethyl-2,4,6-nonatriene, 129,in C. truncatus [270], (3 ,5 ,7 )-5-ethyl-methyl-3,5,7-undecatetraene, 132, in C. mutillatus [271],(2 ,4 ,6 ,8 )-3,5,7-trimethyl-2,4,6,8-decatetraene, 134,in C. hemipterus [272] as well as C. brachypterus [273], (2 ,4 ,6 ,8 )-3,5,7-tri-... 

The biosyntheses of the sap beetle pheromones has been carefully investigated by Bartelt and his co-workers [47,48]. The typical methyl-branching of the compounds originates from propanoate (or methylmalonate) units that form the principal structures (see Fig. 2). Replacement of propanoate by butyrate during chain elongation yields ethyl-branching. In about half of the compounds (125-128,133-136,138-140, and 144) the structures suggest acetate to act as a starter while in 133 and 147 the starter should be butyrate. The chains... 

Bartelt RJ (1999) Sap beetles. In Hardie J, Minks AK (eds) Pheromones of non-lepi-dopteran insects associated with agricultural plants. CABI Publishing, Oxford, UK... 

The male-produced volatiles eficiting responses from male and female antennae of the sap beetle, Colopterus truncatus Randall (Coleoptera Nitidulidae), were identified as (2A ,4A ,6A )-3,5-dimethyl-2,4,6-octa-triene, 2E, AE, 6T )-4,6-dimethyl-2,4,6-nonatriene and 2E, AE,6E,SE) 3,5,7-trimethyl-2,4,6,8-decatetraene. A fourth male-specific compound... 

Bartelt R. J. (1999a) Sap beetles. In Pheromones ofNon-Lepidopteran Insects Associated with Agricultural Plants, eds J. Hardie and A. K. Minks, pp. 69-89. CABI Publishing, New York. 

Dowd P. F. and Bartelt R. J. (1993) Aggregation pheromone glands of Carpophilus freemani (Coleoptera Nitidulidae) and gland distribution among other sap beetles. Ann. Entomol. Soc. Am. 86, 464 -69. 

Bartelt, R. J., Dowd, P. F., Vetter, R. S., Shorey, H. H. and Baker, T. C. (1992a). Responses of Carpophilus hemipterus (Coleoptera Nitidulidae) and other sap beetles to the pheromone of C. hemipterus and host-related coattractants in California field tests. Environ. Entomol., 21,1143-1153. 

Bartelt, R. J. and James, D. G. (1994). Aggregation pheromone of Australian sap beetle, Carpophilus davidsoni (Coleoptera Nitidulidae)../. Chem. Ecol., 20, 3207-3219. 

Connell, W.A. (1991). Sap beetles (Nitidulidae, Coleoptera). In Insect and Mite Pests in Food, Vol. 1, ed. J. R. Gorham. Agricultural Handbook Number 65, United States Department of Agriculture and United States Department of Health and Human Services. Washington, DC United States Government Printing Office, pp. 151-174. 

Dowd, P. F. (2000). Dusky sap beetles (Coleoptera Nitidulidae) and other kernel damaging insects in Bt and non-Bt sweet com in Illinois../. Econ. Entomol., 93, 1714-1720. 

Dowd, P.F., Bartelt, R. J. and Wicklow, D.T. (1992). Novel insect trap useful in capturing sap beetles (Coleoptera Nitidulidae) and other flying insects. J. Econ. Entomol., 85, 772-778. 

Semiochemical-mediated flight responses of sap beetle vectors of oak wilt, Ceratocystis fagacearum. J. Chem. Ecol., 28,1527-1547. 

Pena, J.E., Castineiras, A., Bartelt, R. and Duncan, R. (1999). Effect of pheromone bait stations for sap beetles (Coleoptera Nitidulidae) on Annona spp. fruit set. Fla. Entomol., 82,475 180. 

Nematoda Mermithidae) from sap beetles (Coleoptera Nitidulidae) with biological observations and a key to the species of Psammomermis. Fund. Appl. Nematol., 20, 207-211. 

Kernels at tips or upper half of ears hollowed out. Cause Sap beetles. These small black beetles with yellow spots invade ears after the silks turn brown. Handpick beetles, or spray ear tips with a commercial pyrethrin solution for severe infestations. Sap beetles can be trapped in containers baited with fermenting fruit. 

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