CORRELATION OF 1-OCTEN-3-ONE WITH ANTIXENOTIC RESISTANCE IN SUBTERRANEAN CLOVER COTYLEDONS TO RED-LEGGED EARTH MITE, HALOTYDEUS DESTRUCTOR (ACARINA, PENTHALEIDAE)
Y. Jiang et al., CORRELATION OF 1-OCTEN-3-ONE WITH ANTIXENOTIC RESISTANCE IN SUBTERRANEAN CLOVER COTYLEDONS TO RED-LEGGED EARTH MITE, HALOTYDEUS DESTRUCTOR (ACARINA, PENTHALEIDAE), Journal of chemical ecology, 22(2), 1996, pp. 369-382
Artificially damaged cotyledons of subterranean clover (Trifolium subt
erraneum L.) released several volatile metabolites, including 1-octen-
3-one, arising from lipid peroxidation. The amount of 1-octen-3-one pr
oduced was negatively correlated with feeding damage caused by the red
-legged earth mite (Halotydeus destructor) in nine out of 10 resistant
and susceptible T. subterraneum varieties tested. The EC(50) of this
compound in deterring mites from feeding in a membrane bioassay was 50
ppm. Cotyledon toughness was also involved in resistance. The resista
nt variety, S3615D, which has the lowest toughness value among the res
istant varieties, produced the highest amount of 1-octen-3-one recover
ed from the headspace in 1 hr. Artificially damaged cotyledons of both
susceptible Dalkeith and resistant DGI007, growing in shade, showed l
ower toughness, but had enhanced production of C-8 volatile compounds
and were avoided by mites during a 3-hr feeding test. When both 1-octe
n-3-one content and cotyledon toughness value were taken as cofactors
in resistance, the resultant multiplication value yielded a more signi
ficantly negative correlation with mite feeding damage scores within t
he 10 varieties than either factor alone. We conclude that 1-octen-3-o
ne has a role in resistance of subclover cotyledon to the mite.