Current and planned research for managing the risk of Xylella fastidiosa to New Zealand

Xylella fastidiosa (Xf), a xylem-limited bacterium native to the Americas, has a devastating impact on many crops internationally. In California, Xf causes over USD 100 million in yearly losses to the grape industry and infects an estimated 200 million citrus trees in Brazil. More recently, Xf killed around one million olive trees on the Italian peninsula of Salento. Xylella fastidiosa is not known to be present in New Zealand. The glassy-winged sharpshooter (Homalodisca vitripennis), an important vector of Xf in California, is also not present in New Zealand. However, the meadow spittle bug (Philaenus spumarius), an important vector of Xf in Italy, is present. Many economically important horticultural, viticultural, agricultural, amenity and indigenous/native plant species, including taonga, are likely to be susceptible to Xf. Aspects of our research on Xf to understand the impact, reduce the likelihood of entry into New Zealand and/or minimising its impact in New Zealand will be presented. The research listed on the poster spans risk assessment, diagnostics, surveillance and biological control but could certainly be increased across the biosecurity continuum given the magnitude of the threat from Xf to New Zealand’s valuable plant systems.

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Biological and Host Range Characteristics of Lysathia flavipes (Coleoptera: Chrysomelidae), a Candidate Biological Control Agent of Invasive Ludwigia spp. (Onagraceae) in the USA

Insects ◽

10.3390/insects12050471 ◽

2021 ◽

Vol 12 (5) ◽

pp. 471

Author(s):

Angelica M. Reddy ◽

Paul D. Pratt ◽

Brenda J. Grewell ◽

Nathan E. Harms ◽

Ximena Cibils-Stewart ◽

...

Keyword(s):

Biological Control ◽

Host Range ◽

Plant Species ◽

Biocontrol Agent ◽

Biological Control Agent ◽

Control Agent ◽

Native Plant ◽

Native Plant Species ◽

The Usa ◽

Physical And Chemical

Exotic water primroses (Ludwigia spp.) are aggressive invaders in aquatic ecosystems worldwide. To date, management of exotic Ludwigia spp. has been limited to physical and chemical control methods. Biological control provides an alternative approach for the management of invasive Ludwigia spp. but little is known regarding the natural enemies of these exotic plants. Herein the biology and host range of Lysathia flavipes (Boheman), a herbivorous beetle associated with Ludwigia spp. in Argentina and Uruguay, was studied to determine its suitability as a biocontrol agent for multiple closely related target weeds in the USA. The beetle matures from egg to adult in 19.9 ± 1.4 days at 25 °C; females lived 86.3 ± 35.6 days and laid 1510.6 ± 543.4 eggs over their lifespans. No-choice development and oviposition tests were conducted using four Ludwigia species and seven native plant species. Lysathia flavipes showed little discrimination between plant species: larvae aggressively fed and completed development, and the resulting females (F1 generation) oviposited viable eggs on most plant species regardless of origin. These results indicate that L. flavipes is not sufficiently host-specific for further consideration as a biocontrol agent of exotic Ludwigia spp. in the USA and further testing is not warranted.

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Current and planned research for managing the fruit fly threat to New Zealand

New Zealand Plant Protection ◽

10.30843/nzpp.2019.72.326 ◽

2019 ◽

Vol 72 ◽

pp. 279

Author(s):

David A.J. Teulon ◽

John M. Kean ◽

Karen F. Armstrong

Keyword(s):

Risk Assessment ◽

Risk Management ◽

New Zealand ◽

Fruit Fly ◽

Fruit Flies ◽

Bactrocera Tryoni ◽

The World ◽

Increasing Risk ◽

Management Diagnostics ◽

The Impact

Fruit flies (Family Tephritidae), in particular the Queensland fruit fly (Bactrocera tryoni; QFF), areone of the biggest biosecurity risks for New Zealand horticulture. New Zealand has one of the bestscience-based biosecurity systems in the world, based on years of experience and sound research. Theintroduction of fruit flies to New Zealand is now well managed in commercial fruit imports, but the riskis rising from growing trade and travel and, in the case of QFF, climatic adaptation and spread to moresouthern localities. Smarter solutions are continually needed to manage this increasing risk, and to dealwith such pests when they arrive. We present a brief summary of current and anticipated research aimedat reducing the likelihood of entry into New Zealand and/or minimising the impact for the fruit flyspecies of greatest threat to New Zealand. Research spans risk assessment, pathway risk management,diagnostics, surveillance and eradication.

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Extended distribution and host plants of Nameriophyes sapidae Xue & Zhang 2008 (Acari: Eriophyidae) in New Zealand

Zootaxa ◽

10.11646/zootaxa.2796.1.6 ◽

2011 ◽

Vol 2796 (1) ◽

pp. 67

Author(s):

NICHOLAS A. MARTIN ◽

ZHI-QIANG ZHANG

Keyword(s):

New Species ◽

New Zealand ◽

Plant Species ◽

Host Plants ◽

Mite Species ◽

Native Plant ◽

Native Plant Species ◽

The North ◽

A New Species

Nameriophyes sapidae Xue & Zhang (Acari: Eriophyidae) was found on transplanted nikau palms, Rhopalostylis sapida (H. Wendl. & Drude) in Auckland, New Zealand and described as a new species (Xue & Zhang 2008). Although R. sapida is a native plant species, it was not known if this mite species was indigenous or adventive because it was collected only from transplanted palms in unnatural gardens in Auckland. A survey was undertaken of R. sapida and the Kermadec Island palm, Rhopalostylis baueri (Hook. f.) Wendl. & Drude in the northern part of the North Island and Chatham Island.

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Response of endemic and exotic earthworm communities to ecological restoration

10.7287/peerj.preprints.2017v1 ◽

2016 ◽

Author(s):

Stéphane Boyer ◽

Young-Nam Kim ◽

Mike H Bowie ◽

Marie-Caroline Lefort ◽

Nicholas M Dickinson

Keyword(s):

New Zealand ◽

Exotic Species ◽

Environmental Changes ◽

Farming Systems ◽

Native Vegetation ◽

Native Plant ◽

Plant Restoration ◽

Exotic Earthworms ◽

Study Sites ◽

The Impact

New Zealand has 23 exotic and more than 200 endemic earthworm species. Endemic earthworms disappeared quickly after vegetation clearance and land conversion to agriculture from the early C19th. Environmental changes associated with agronomic practices are believed to have been the main drivers for their disappearance. Exotic earthworms introduced from Europe have since largely replaced endemic earthworms into farming systems and have been intentionally propagated to increase production. Little is known about potential competition between endemic and exotic earthworms in New Zealand, and the capacity of exotic earthworms to extend their range into native habitats. Using two sites in the South Island of New Zealand, we investigated the impact of restoring native vegetation on earthworm communities. The study sites were Quail Island (Banks Peninsula), which has been undergoing native plant restoration for more than 30 years, and the Punakaiki Coastal Restoration Project (West Coast) where 130,000 native trees have been planted in retired pasture in the last seven years. At each site, soil samples (20 x 20 x 20 cm) were collected and hand sorted for earthworms. Sequential restoration plantings revealed that recolonisation by endemic earthworms increases with time after restoration at the two sample sites. With increasing age of the restoration, the biomass of endemic earthworm significantly increased, as did abundance at Punakaiki. However, exotic species did not disappear after restoration of native vegetation, even after 30 years in Quail Island. The persistence of exotic species leads to the cohabitation of the two communities and potential for interspecific competition.

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Do Cultivars of Native Plants Support Insect Herbivores?

HortTechnology ◽

10.21273/horttech03957-18 ◽

2018 ◽

Vol 28 (5) ◽

pp. 596-606 ◽

Cited By ~ 3

Author(s):

Emily C. Baisden ◽

Douglas W. Tallamy ◽

Desiree L. Narango ◽

Eileen Boyle

Keyword(s):

Disease Resistance ◽

Food Webs ◽

Native Plants ◽

Fruit Size ◽

Common Garden ◽

Insect Herbivores ◽

Native Plant ◽

Genetic Changes ◽

Native Plant Species ◽

The Impact

Native plants are becoming widely used in built landscapes to help mitigate the loss of biodiversity caused by urbanization. The primary advantage of native plant species over introduced ornamentals is their ability to support the development of the insects that fuel vertebrate food webs as well as specialist pollinators. The horticultural industry has introduced many cultivars of native plants to improve their aesthetic value and disease resistance, but there has been little work that measures the impact of these genetic changes on insect herbivores and pollinators. Here we measure how six desirable traits in native woody plant cultivars (leaf color, variegation, fall color, habit, disease resistance, and fruit size) compare with their wild types in terms of their ability to support insect herbivore development, abundance, and species richness. Using a common garden experiment, we quantified the abundance and diversity of insect herbivores using each species and its cultivars for growth and development over a 2-year period, as well as cumulative feed damage over the entire season. We also conducted feeding tests with evergreen bagworm (Thyridopteryx ephemeraeformis) to measure the preference of hatchling caterpillars for cultivars vs. straight species. We found that cultivars that had leaves altered from green to red, blue, or purple deterred insect feeding in all three experiments, a preference for variegated cultivars in one of our three experiments, but no consistent pattern of use among the species and cultivars chosen for other traits. These results suggest that the usefulness of native cultivars in restoring insect-driven food webs depends on the cultivar trait that has been selected.

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Current status of classical biological control of Cirsium arvense in New Zealand

New Zealand Plant Protection ◽

10.30843/nzpp.2010.63.6580 ◽

2010 ◽

Vol 63 ◽

pp. 273-273

Author(s):

M.G. Cripps ◽

G.W. Bourd?t ◽

S.V. Fowler ◽

G.R. Edwards

Keyword(s):

Biological Control ◽

New Zealand ◽

Natural Enemies ◽

Classical Biological Control ◽

Growth Characteristics ◽

Cirsium Arvense ◽

Current Status ◽

Perennial Herb ◽

Rust Pathogen ◽

The Impact

Cirsium arvense (L) Scop (Californian Canada or creeping thistle) is an exotic perennial herb that successfully established in New Zealand (NZ) approximately 130 years ago and is now considered one of the worst invasive weeds in NZ arable and pastoral systems Two insects Cassida rubiginosa and Ceratapion onopordi were recently released for classical biological control Studies carried out from 2006 to 2009 in both the native (Europe) and introduced (NZ) ranges of the plant aimed to quantify C arvense growth characteristics and assess incidence of the specialised rust pathogen Puccinia punctiformis in regions with and without the supposed pathogen vector C onopordi In permanent field plots natural enemies were excluded with insecticides and fungicides and compared with controls The impact of C rubiginosa was also assessed under different pasture competition scenarios The survey data indicate that C arvense expresses similar growth characteristics in both ranges and that incidence of the rust pathogen is similar in both ranges regardless of the presence of C onopordi The data suggest that the overall suite of natural enemies is capable of exerting some regulating influence on the plant in its native range but that the released biocontrol agents will not likely have a significant impact on this weed in NZ

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Biosafety testing and risk assessment for biological control of forest insect pests in New Zealand

10.1603/ice.2016.94667 ◽

2016 ◽

Author(s):

Toni M. Withers

Keyword(s):

Risk Assessment ◽

Biological Control ◽

New Zealand ◽

Insect Pests ◽

Forest Insect

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Postrelease Evaluation of Mecinus janthinus Host Specificity, a Biological Control Agent for Invasive Toadflax (Linaria spp.)

Weed Science ◽

10.1614/ws-06-093.1 ◽

2007 ◽

Vol 55 (2) ◽

pp. 164-168 ◽

Cited By ~ 10

Author(s):

Nehalem C. Breiter ◽

Timothy R. Seastedt

Keyword(s):

Biological Control ◽

Host Specificity ◽

Plant Species ◽

Field Experiments ◽

Biological Control Agent ◽

Control Agent ◽

Native Plant ◽

Weed Biological Control ◽

Native Plant Species ◽

Mecinus Janthinus

Toadflax invasion into natural areas has prompted interest in weed management via biological control. The most promising biological control agent currently available for the control of Dalmatian toadflax is Mecinus janthinus, a stem-boring weevil that has been shown to significantly reduce toadflax populations. Some land managers, however, are reluctant to release approved weed biological control agents based on concerns about possible nontarget impacts. Few postrelease examinations of biocontrol impact and host specificity have been performed, despite the call for such information. This study examined the host specificity of Mecinus janthinus, postrelease, in relation to Colorado sites to provide information to managers about its relative safety as a weed biological control agent. This study employed three components: (1) greenhouse choice and no-choice experiments; (2) no-choice caged field experiments; and (3) release-site evaluation of nontarget use of native plant species where this weevil has been released and has established. Both greenhouse and field experiments failed to demonstrate nontarget use of native plant species by M. janthinus in the region where it was studied, even in no-choice starvation tests. We found no evidence of nontarget herbivory on native plants growing at toadflax sites where M. janthinus was well established. These results support the continued use of M. janthinus as a low-risk biological control agent for the management of toadflax in the Rocky Mountain Front Range.

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