Premium
The effects of floral understoreys on parasitism of leafrollers (Lepidoptera: Tortricidae) on apples in New Zealand
Author(s) -
Irvin N. A.,
Scarratt S. L.,
Wratten S. D.,
Frampton C. M.,
Chapman R. B.,
Tylianakis J. M.
Publication year - 2006
Publication title -
agricultural and forest entomology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.755
H-Index - 55
eISSN - 1461-9563
pISSN - 1461-9555
DOI - 10.1111/j.1461-9555.2006.00285.x
Subject(s) - biology , tortricidae , lepidoptera genitalia , braconidae , botany , horticulture , mating disruption , biological pest control , parasitoid
1 Field and laboratory experiments on the conservation biocontrol of lepidopteran leafroller pests were carried out in apples at Lincoln, New Zealand. 2 Apple understoreys were planted with replicated treatments of alyssum ( Lobularia maritima ), phacelia ( Phacelia tanacetifolia ) and buckwheat ( Fagopyrum esculentum ). 3 Rates of parasitism of experimentally released larvae of the light‐brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), by Dolichogenidea tasmanica (Cameron) (Hymenoptera: Braconidae) were significantly lower in phacelia and control treatments, and leafroller pupae were significantly more abundant in controls than in buckwheat and alyssum treatments. 4 Naturally occurring leafroller damage was up to 29% lower above all the floral understorey treatments compared with controls and there were more than twice as many D. tasmanica cocoons in the alyssum and buckwheat treatments than in controls. 5 Suction sampling of the understoreys gave D. tasmanica adult densities that were significantly more abundant in alyssum compared with other treatments. Numbers of Anacharis zealandica (Hymenoptera: Figitidae) (a parasitoid of larvae of the predatory brown lacewing) did not differ between treatments. 6 In the laboratory, flowering buckwheat and alyssum enhanced D. tasmanica longevity by up to 78% compared with the control, and buckwheat also enhanced potential fecundity by 62%. 7 In choice experiments, leafroller larvae in the laboratory consumed more than three‐fold more apple leaf material than they did of the three understorey species, although alyssum increased leafroller fecundity and longevity. 8 The use of floral understoreys for conservation biocontrol of apple pests is discussed, along with the potential negative effects of some flowering species on pest populations and orchard agronomic practices.