Davidsoni

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-... 

Bartelt, R. J. and Weisleder, D. (1996). Polyketide origin of pheromones of Carpophilus davidsoni and C. mutilatus (Coleoptera Nitidulidae). Bioorganic and Medicinal Chemistry 4 429 138. 

Another biosynthetic issue is the origin of complex hydrocarbon blends, such as the 11 different tetraenes of Ca. hemipterus (Figure 19.3). While there could be separate biosynthetic systems for each of the Ca. hemipterus tetraenes, a more parsimonious explanation, which fits the data, is that a single biosynthetic system exists with imperfect selectivity for acyl units (Bartelt et al., 1992b). If the most abundant tetraene, 5, represents the normal product, then tetraenes 6,7,14, and 18 represent instances of one acyl substitution (or biosynthetic mistake ). There are six possible ways in which two of these substitutions could exist in one compound, and these are represented by 8,15,16,19,20, and 21. Occurrence of two substitutions would be rarer than just one, and the observed abundances reflected this expectation. Tetraenes with three or four substitutions would be even rarer, and these were not detected. Substitutions were never observed for the second acyl unit, which was unfailingly propionate. Related arguments can be made for the patterns of hydrocarbons in Ca. freemani and Ca. davidsoni (Bartelt et al., 1990b Bartelt and Weisleder, 1996). 

Ca. davidsoni (James et al., 1997). Abreu (1997) demonstrated in Brazil that Ca. dimid-iatus and Ca. obsoletus could be detected in cocoa warehouses with pheromone traps. Monitoring traps have also been used to survey beetles in different habitats for infestation by natural enemies such as nematodes (Dowd et al., 1995) these efforts resulted in the discovery of a new nematode species (Poinar and Dowd, 1997). Dowd (2000) used the pheromone of Ca. lugubris to compare infestations of these beetles in Bt and non-Bt sweet com in Illinois. Dispersal of oak wilt fungus by Co. truncatus and Ca. sayi has been investigated with the aid of pheromone traps (Amboum et al., 2005). 

The most intensive effort to use pheromones in insect management has been in Australia, where an attract-and-kill strategy has been developed for protecting stone fruit crops. Historically, the Oriental fruit moth, Grapholita molesta Busck, was the major stone fruit pest, and heavy insecticide applications kept both this moth and, coincidentally, the Carpophilus beetles at acceptable levels. However, the widespread adoption of pheromone-based mating disruption for G. molesta control released the Carpophilus beetles from insecticide pressure, and these beetles, Ca. davidsoni in particular, became the dominant stone fruit pests (James et al., 1994). Late applications of broad-spectrum insecticides often... 

Bartelt, R. J. and Hossain, M. S. (2006). Development of synthetic food-related attractant for Carpophilus davidsoni and its effectiveness in the stone fruit orchards in southern Australia../. Chem. Ecol., 32, 2145-2162. 

James, D.G., Vogele, B., Faulder, R. J. and Moore, C. J. (2000c). Efficacy of multispecies pheromone lures for Carpophilus davidsoni Dobson and Carpophilus mutilatus Erichson (Coleoptera Nitidulidae). Aust. J. Entomol., 39, 83-85. 

E Terebratulina crossei Terebratulina pacifica Gryphus davidsoni... 

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