The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, W... more The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, West Auckland in May 1999, prompted an area-wide eradication programme by the New Zealand Ministry of Agriculture and Forestry Biosecurity Authority. The Australian painted apple moth is a polyphagous pest of horticulture and plantation forestry and threatened New Zealand's native vegetation. The economic and ecological impact of the moth's incursion was estimated at NZD 50-350 million (approximately USD 30.5-212.9 million) over 20 years if no action was taken to eradicate the insect. The eradication programme (1999-2006) used a combination of tactics, including the first use of the sterile insect technique (SIT) in New Zealand. The SIT component was added to the eradication programme in 2002 but releases started in 2003 as an end game tactic once the pest population was brought down to ca 1% of the population level in 2001-2002, as indicated by trap catches. The aerial spray prog...
Different combinations of shoots of 30 Salix species, clones or identified hybrids, were exposed ... more Different combinations of shoots of 30 Salix species, clones or identified hybrids, were exposed to Nematus oligospilus to determine which were preferred for oviposition. Single N. oligospilus, enclosed in gauze cages, chose from 9 -12 terminal shoots in which to oviposit. There was wide variation in fecundity (49.3±4.3 eggs/female; range 0-100). Sawflies oviposited in all tree-willows (subgenus Salix) screened -a selection dominated by clones of S. matsudana x S. alba hybrids, but wide variation in the number of eggs laid/shoot prevented a significant preference ranking. Shrub willows (subgenus Caprisalix) were, with one exception, not selected for oviposition. INTRODUCTION Nematus oligospilus Förster (Hymenoptera: Tenthredinidae), a sawfly that feeds exclusively on willows (Salix spp.), was discovered in Auckland on 19 February 1997 (Berry 1997). Adult N. oligospilus disperse rapidly by flight, and by the autumn of 1997 the species was widespread throughout the Auckland isthmus (B...
Between January 2002 and May 2004 a series of aerially applied sprays of Btk (Bacillus thuringien... more Between January 2002 and May 2004 a series of aerially applied sprays of Btk (Bacillus thuringiensis var. kurstaski) were made to areas of Auckland and Hamilton, New Zealand. The purpose of the sprays was to eradicate the painted apple moth (PAM; Teia anartoides) from Auckland and the Asian gypsy moth (AGM; Lymantria dispar) from Hamilton. In both operations, bioassays were used to test the effectiveness and consistency of spray applications. Bioassays were undertaken by placing foliage samples (Acacia mearnsii) at a selection of locations in the spray zone next to cards on which spray deposition was measured. After spraying, PAM larvae were placed on each plant and mortality recorded. Results indicated that there was a strong relationship between droplet density on cards and PAM mortality on plants. Once this relationship was determined, further bioassays were of limited additional value to simply measuring deposition on cards. INTRODUCTION Painted apple moth (PAM; Teia anartoides ...
Citrus red mite (CRM) populations can reach high levels in citrus orchards in New Zealand after t... more Citrus red mite (CRM) populations can reach high levels in citrus orchards in New Zealand after the application of broad-spectrum pesticides to control other pests. It is important to know which are the key biological control agents of CRM in New Zealand in order to minimize the use of pesticides toxic to these natural enemies. CRM and natural enemies were monitored in seven orchards from January 2004 to March 2005. Ladybirds, Stethorus sp. and Halmus chalybeus, and predatory mites, Agistemus longisetus, Amblyseius largoensis and Phytoseiulus persimilis, were observed consuming CRM. Stethorus sp. and A. longisetus were the most abundant natural enemies found with CRM. The presence of 0.5 live Stethorus sp. per leaf and 0.5-1 A. longisetus per leaf was associated with the decline of CRM populations (15 eggs and 15 juvenile/adults per leaf) to 'trace' levels in 4-5 weeks. The use of neonicotinoid products can disrupt the predatory activity of Stethorus sp. against CRM.
ABSTRACT The ladybird Stethorus sp. and the predatory mite Agistemus longisetus are the most abun... more ABSTRACT The ladybird Stethorus sp. and the predatory mite Agistemus longisetus are the most abundant natural enemies found with high populations of citrus red mite (CRM) ( Panonychus citri). To enable the continued use of pesticides that may be toxic to one or both of these predators, knowledge of their roles in regulating CRM populations is required. In laboratory bioassays, both natural enemies alone and in combination reduced the number of eggs and immature CRM. However, A. longisetus alone did not reduce the number of CRM adults as effectively as Stethorus sp. alone or in combination. In a glasshouse trial, predation by a combination of Stethorus sp. and A. longisetus reduced CRM populations faster than predation by Stethorus sp. alone. Stethorus sp. is the more effective of the two common CRM natural enemies at reducing high populations of CRM, but the combined predation of the two predators may be complementary in highly dispersed populations where there are a large number of leaves with few eggs.
ABSTRACT The incursion of the native Australian painted apple moth Teia anartoides Walker into Gl... more ABSTRACT The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, West Auckland in May 1999, prompted an area-wide eradication programme by the New Zealand Ministry of Agriculture and Forestry Biosecurity Authority. The ...
ABSTRACT Cohorts of willow sawfly (Nematus oligospilus) were reared in the laboratory on crack wi... more ABSTRACT Cohorts of willow sawfly (Nematus oligospilus) were reared in the laboratory on crack willow (Salix fragilis) at seven constant temperatures between 11.3 and 28.8°C. Larvae developed through 5–7 instars. Body size (length) of adult females was influenced by temperature and was strongly correlated with fecundity (R = 0.8973). The developmental threshold (to), determined through linear regression, was calculated to be 8.1°C, and the thermal accumulation above to required to complete one generation was 321 degree‐days. The number of degree‐days available for seasonal development of the sawfly at 10 sites throughout New Zealand was calculated. Allowing for the period of diapause, it was estimated that N. oligospilus might potentially develop through up to seven generations per year in the North Island and three generations per year in the south of the South Island.
The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, W... more The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, West Auckland in May 1999, prompted an area-wide eradication programme by the New Zealand Ministry of Agriculture and Forestry Biosecurity Authority. The Australian painted apple moth is a polyphagous pest of horticulture and plantation forestry and threatened New Zealand's native vegetation. The economic and ecological impact of the moth's incursion was estimated at NZD 50-350 million (approximately USD 30.5-212.9 million) over 20 years if no action was taken to eradicate the insect. The eradication programme (1999-2006) used a combination of tactics, including the first use of the sterile insect technique (SIT) in New Zealand. The SIT component was added to the eradication programme in 2002 but releases started in 2003 as an end game tactic once the pest population was brought down to ca 1% of the population level in 2001-2002, as indicated by trap catches. The aerial spray prog...
Different combinations of shoots of 30 Salix species, clones or identified hybrids, were exposed ... more Different combinations of shoots of 30 Salix species, clones or identified hybrids, were exposed to Nematus oligospilus to determine which were preferred for oviposition. Single N. oligospilus, enclosed in gauze cages, chose from 9 -12 terminal shoots in which to oviposit. There was wide variation in fecundity (49.3±4.3 eggs/female; range 0-100). Sawflies oviposited in all tree-willows (subgenus Salix) screened -a selection dominated by clones of S. matsudana x S. alba hybrids, but wide variation in the number of eggs laid/shoot prevented a significant preference ranking. Shrub willows (subgenus Caprisalix) were, with one exception, not selected for oviposition. INTRODUCTION Nematus oligospilus Förster (Hymenoptera: Tenthredinidae), a sawfly that feeds exclusively on willows (Salix spp.), was discovered in Auckland on 19 February 1997 (Berry 1997). Adult N. oligospilus disperse rapidly by flight, and by the autumn of 1997 the species was widespread throughout the Auckland isthmus (B...
Between January 2002 and May 2004 a series of aerially applied sprays of Btk (Bacillus thuringien... more Between January 2002 and May 2004 a series of aerially applied sprays of Btk (Bacillus thuringiensis var. kurstaski) were made to areas of Auckland and Hamilton, New Zealand. The purpose of the sprays was to eradicate the painted apple moth (PAM; Teia anartoides) from Auckland and the Asian gypsy moth (AGM; Lymantria dispar) from Hamilton. In both operations, bioassays were used to test the effectiveness and consistency of spray applications. Bioassays were undertaken by placing foliage samples (Acacia mearnsii) at a selection of locations in the spray zone next to cards on which spray deposition was measured. After spraying, PAM larvae were placed on each plant and mortality recorded. Results indicated that there was a strong relationship between droplet density on cards and PAM mortality on plants. Once this relationship was determined, further bioassays were of limited additional value to simply measuring deposition on cards. INTRODUCTION Painted apple moth (PAM; Teia anartoides ...
Citrus red mite (CRM) populations can reach high levels in citrus orchards in New Zealand after t... more Citrus red mite (CRM) populations can reach high levels in citrus orchards in New Zealand after the application of broad-spectrum pesticides to control other pests. It is important to know which are the key biological control agents of CRM in New Zealand in order to minimize the use of pesticides toxic to these natural enemies. CRM and natural enemies were monitored in seven orchards from January 2004 to March 2005. Ladybirds, Stethorus sp. and Halmus chalybeus, and predatory mites, Agistemus longisetus, Amblyseius largoensis and Phytoseiulus persimilis, were observed consuming CRM. Stethorus sp. and A. longisetus were the most abundant natural enemies found with CRM. The presence of 0.5 live Stethorus sp. per leaf and 0.5-1 A. longisetus per leaf was associated with the decline of CRM populations (15 eggs and 15 juvenile/adults per leaf) to 'trace' levels in 4-5 weeks. The use of neonicotinoid products can disrupt the predatory activity of Stethorus sp. against CRM.
ABSTRACT The ladybird Stethorus sp. and the predatory mite Agistemus longisetus are the most abun... more ABSTRACT The ladybird Stethorus sp. and the predatory mite Agistemus longisetus are the most abundant natural enemies found with high populations of citrus red mite (CRM) ( Panonychus citri). To enable the continued use of pesticides that may be toxic to one or both of these predators, knowledge of their roles in regulating CRM populations is required. In laboratory bioassays, both natural enemies alone and in combination reduced the number of eggs and immature CRM. However, A. longisetus alone did not reduce the number of CRM adults as effectively as Stethorus sp. alone or in combination. In a glasshouse trial, predation by a combination of Stethorus sp. and A. longisetus reduced CRM populations faster than predation by Stethorus sp. alone. Stethorus sp. is the more effective of the two common CRM natural enemies at reducing high populations of CRM, but the combined predation of the two predators may be complementary in highly dispersed populations where there are a large number of leaves with few eggs.
ABSTRACT The incursion of the native Australian painted apple moth Teia anartoides Walker into Gl... more ABSTRACT The incursion of the native Australian painted apple moth Teia anartoides Walker into Glendene, West Auckland in May 1999, prompted an area-wide eradication programme by the New Zealand Ministry of Agriculture and Forestry Biosecurity Authority. The ...
ABSTRACT Cohorts of willow sawfly (Nematus oligospilus) were reared in the laboratory on crack wi... more ABSTRACT Cohorts of willow sawfly (Nematus oligospilus) were reared in the laboratory on crack willow (Salix fragilis) at seven constant temperatures between 11.3 and 28.8°C. Larvae developed through 5–7 instars. Body size (length) of adult females was influenced by temperature and was strongly correlated with fecundity (R = 0.8973). The developmental threshold (to), determined through linear regression, was calculated to be 8.1°C, and the thermal accumulation above to required to complete one generation was 321 degree‐days. The number of degree‐days available for seasonal development of the sawfly at 10 sites throughout New Zealand was calculated. Allowing for the period of diapause, it was estimated that N. oligospilus might potentially develop through up to seven generations per year in the North Island and three generations per year in the south of the South Island.
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