scholarly journals Recent introduction and establishment of the leafroller parasitoid Trigonospila brevifacies (Hardy) (Diptera Tachinidae) in Nelson

2001 ◽  
Vol 54 ◽  
pp. 33-36
Author(s):  
P.W. Shaw ◽  
P. Lo ◽  
D.R. Wallis
Keyword(s):  
Fourth Instar ◽  
Biocontrol Agents ◽  
Research Centre ◽  
Epiphyas Postvittana ◽  
Natural Distribution ◽  
Laboratory Colony ◽  
Important Pest ◽  
Successful Establishment ◽  
Lightbrown Apple Moth ◽  
Natural Dispersal

To assist the natural distribution of the leafroller parasitoid Trigonospila brevifacies to horticultural areas in the Nelson region 181 T brevifacies pupae and 329 adults were released in 1999 at four sites adjacent to apple orchards near Motueka Release material was supplied from fieldcollected parasitoids in Hawkes Bay and a laboratory colony held at the Mt Albert Research Centre in Auckland Successful establishment of the parasitoid was recorded at all four sites and at a nearby nonrelease site in 2000 In 2000 319 of fourth instar and older larvae were parasitised by T brevifacies while in 2001 parasitism was 1166 Important pest tortricid species including Epiphyas postvittana (Walker) (lightbrown apple moth) were among the hosts The successful establishment of T brevifacies in Nelson and its further natural dispersal will increase the potential for the reduction of economically important leafroller species by biocontrol agents

A SECONDARY EFFECT OF DDT UPON THE AQUATIC MICROFLORA AND MICROFAUNA

1958 ◽  
Vol 4 (5) ◽  
pp. 445-452 ◽  
Author(s):  
Marshall Laird
Keyword(s):  
Selection Pressure ◽  
Developmental Stages ◽  
Larval Mortality ◽  
Fourth Instar ◽  
Anopheles Maculipennis ◽  
Field Investigations ◽  
Laboratory Colony ◽  
Time Required ◽  
Early Developmental ◽  
Heavy Infestation

Observations were made on the microflora and microfauna of infusions in which larvae of Anopheles maculipennis atroparvus were being subjected to DDT selection pressure (2 μg/ml). Comparisons with controls indicated that the insecticide influenced neither the species representation nor the succession of the organisms concerned. However, heavy initial larval mortality took place. Dead larvae remaining in the containers overnight became centers of very rapid bacterial multiplication, and the maturation of the experimental infusions was accelerated. The larval cultures became polysaprobic after about two weeks, by which time the surviving larvae were in the fourth instar. These survivors were large and healthy, having spent their early developmental period in the presence of a rich supply of infusion organisms answering their food requirements, and successfully withstood the deteriorating environmental conditions and consequent heavy infestation with epibionts (Chlamydobacteriales and peritrichous ciliates). On the other hand, fourth instar larvae from similar infusions in the laboratory colony of A, m. atroparvus were often undersized and sickly because of early overcrowding linked with the initially longer time required for the development of an adequate yield of food organisms. Such larvae, also pupae, frequently died of exhaustion due to undernourishment and complicated by the hampering of their activity by a vestiture of bacteria and ciliates. This explained the paradox that adults derived from the laboratory colony tended to be less robust than those hatching from developmental stages subjected to DDT selection pressure. Besides pointing to the importance of paying due regard to larval environmental factors in resistance studies, these observations suggest the need for field investigations of the significance of similar chains of events in nature.

scholarly journals Parasitoids of leafrollers (LepidopteraTortricidae) from scrub vegetation near horticultural areas in Nelson

2015 ◽  
Vol 68 ◽  
pp. 193-196
Author(s):  
P.W. Shaw ◽  
D.R. Wallis
Keyword(s):  
Host Plants ◽  
Epiphyas Postvittana ◽  
Parasitoid Species ◽  
Lightbrown Apple Moth

Leafroller larvae and pupae were collected during timed searches in January and April 2013 from host plants at six scrub vegetation sites in two Nelson horticultural districts approximately 40 km apart The numbers of leafrollers and parasitoid species recovered were similar in both districts Most of the leafroller larvae collected were Epiphyas postvittana (Walker) (lightbrown apple moth LBAM) and most of these were found on gorse and broom In total 293 larvae and 11 pupae were reared successfully with 39 parasitism A wide diversity of parasitoids was recovered comprising 10 species from five families with Dolichogenidea tasmanica (Braconidae) the most common (80) The diversity of parasitoids and parasitism of leafrollers in unmanaged environments outside orchards may help to reduce leafroller pressure and the risk of fruit infestation in surrounding commercial orchards

Post-harvest disinfestation of apples of the light-brown apple moth Epiphyas postvittana

1978 ◽  
Vol 18 (91) ◽  
pp. 313 ◽  
Author(s):  
A Terauds ◽  
JE Ireson ◽  
PEL Rapley ◽  
JB O'Loughlin
Keyword(s):  
Field Line ◽  
Cold Storage ◽  
Methyl Bromide ◽  
Cold Treatment ◽  
Fourth Instar ◽  
Epiphyas Postvittana ◽  
Artificial Medium ◽  
Post Harvest ◽  
Light Brown Apple Moth

A range of dosages of methyl bromide used according to different chamber and fru:. I+ temperatures, preceded, unaccompanied or followed by cold treatment was found effective in disinfesting apples of the light-brown apple moth, Epiphyas postvittana (Walker), in Tasmania, 1972-1 974. Fumigations were in 1.1 m3 and 14.3 m3 chambers, for 2 or 2+hours, loaded to 40 or 80 per cent of their capacities, and cold storage was for 21 days at 0�C. The disinfestation treatments were tested on apples artificially infested with neonate and fourth instar larvae and on a field line of naturally infested fruit; the onset of fumigation effects on fourth instar larvae in artificial medium was also determined.

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