|STOEVA, ATANASKA - Agricultural University Of Bulgaria|
|HARIZANOVA, VILI - Agricultural University Of Bulgaria|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/14/2010
Publication Date: N/A
Technical Abstract: The eriophyid mite Leipothrix dipsacivagus has been recorded from Serbia and Bulgaria on Dipsacus laciniatus and from France on D. fullonum. Host-specificity tests have shown that it can develop and reproduce only on Dipsacus spp., which indicates that it could be regarded as potential biocontrol agent against invasive teasels in North America. The objective of the present study was to study key aspects of the biology of L. dipsacivagus. The mites for the stock colony were collected from D. laciniatus in Klokotnitsa, Bulgaria and reared on rosettes of D. laciniatus under laboratory conditions. The experiments were designed with two variants – using fertilized and unfertilized females. The parthenogenesis of this mite is arrhenotokous. Unfertilized females produced males only, while the offspring of fertilized females consisted of both sexes. The duration of the egg stage from unfertilized females was 6.32 ± 0.85 days. The egg stage from fertilized females was 5.80 ± 0.63 days for male offspring and 6.90 ± 1.14 days for female offspring. The development time for active immature instars (larva and nymph) hatched from eggs laid by unfertilized females was 3.98 ± 0.57 days and for those hatched from eggs laid by fertilized females was 3.43 ± 0.96 (males) and 5.33 ± 1.56 days (females) respectively. The life cycle (egg to adult) was 10.39 ± 1.16 days for progeny of unfertilized females. The development times from egg to adults for progeny of fertilized females averaged 9.56 ± 1.01 days for males and 11.44 ± 1.39 days for females. Fecundity of fertilized and unfertilized females was also measured. The total egg production per female averaged 18.28 ± 5.60 eggs and the daily egg production was about 1.56 ± 0.60 eggs per female. Adult longevity for males and females averaged 9.30 ± 2.00 and 15.91 ± 4.30 days respectively. The results suggest that L. dipsacivagus could be successfully mass produced in the laboratory for possible use as a biological control agent against invasive teasels.