South American beetle introduced to control weed

A tiny Chilean beetle has been introduced to New Zealand in a bid to control a weed that if left unchecked could potentially become as big a problem as gorse.

Landcare Research recently provided Environment Southland with about 70 barberry seed weevils to release just north of Invercargill as a biocontrol agent for Darwin’s barberry. The fast-spreading orange-flowered thorny shrub has become a huge problem across the country, threatening to overrun native plants and farmland – particularly in Southland.

It is the first time this species of weevil, a type of beetle, has been used as a biocontrol agent anywhere in the world.

There are plans to release several thousand more early next year.

The pilot release of the beetles comes after years of research by Landcare Research, led by researcher Lindsay Smith, and collaboration with Chilean scientists.

The adult weevils will assist in controlling the weed by feeding on the plants’ new growth. However, it is the larvae – that feed on the seeds – which are expected to have the biggest impact, Smith said. Darwin’s barberry produces large numbers of viable seed that can be spread hundreds of meters by birds that consume the fruit on the weed.

“The larvae are the ones that will do the most damage as they will destroy the seeds and reduce the spread of the weed,” Smith said.

Extensive tests were carried out on both the adult weevils and their larvae to ensure they could not damage any other plant species.

Landcare Research scientist Simon Fowler said to destroy the existing Darwin’s barberry infestations would require the addition of other biocontrol agents.

However, researchers are currently focused on establishing the barberry seed weevil first before deciding whether another weevil which attacks the flowers is needed.

Plant pathogens, which could potentially damage the plants themselves, are also being studied to assess their potential.

Fowler said the release of the barberry seed weevil had been a milestone after facing a range of challenges.

Among these hurdles was finding the imported adult beetles were suffering from an unwanted disease. But researchers discovered the disease was not transmitted to the larvae. So they imported the weed’s fruit which contains only the larvae.

However, they then ironically faced difficulties growing the weed in containment. It would quickly drop its flowers and fruit, Fowler said. To overcome this, researchers sought permission from the Ministry for Primary Industries to release the beetles soon after they emerged from the imported fruit once tests had shown them to be free from the disease.

The release of the weevils was approved by the Environmental Protection Authority in 2012. Environment Southland applied for the consent on behalf of the National Biocontrol Collective.

Biopesticides being tested against moth pest

Scientists working under the banner of the Lincoln University based New Zealand Bio-Protection Research Centre are examining how to harness naturally occurring fungi and bacteria as biopesticides capable of killing insect pests.

Centre Director Professor Travis Glare says they are currently performing field trials against the diamondback moth, a caterpillar pest, which has become a major problem worldwide attacking cruciferous crops such as broccoli, cabbage, cauliflower and bok choy.

“About $1 billion per year is spent on trying to control this pest. One of the key challenges posed by the diamondback is its ability to quickly become resistant to chemical pesticides.”

Researchers working on the project are tapping into the expertise of specialists at New Zealand Genomics Ltd (NZGL), a genomics infrastructure provider established in 2010 by three universities – Massey University, The University of Auckland and University of Otago – with support from the Government. NZGL provides an integrated suite of genomic services involving gene sequencing, bioinformatics and genomics appropriate information technology.

Professor Glare says the Bio-Protection Research Centre, a Government-funded Centre of Research Excellence (CoRE), is working with strains of Beauveria, a fungus that acts as a parasite and can kill or seriously disable insects. They are testing chemicals released by the fungus for their potential as active agents in biopesticides.

“Beauveria has a lot of strain variations which generate different toxins capable of killing insect pests. We are particularly interested in working out which genes encode for those toxins.”

“So far we have sequenced four strains of Beauveria, and we plan to compare these with strains from elsewhere in the world to find variations that may be even better.”

Professor Glare says NZGL has proved to be an incredible resource for their research, providing not only gene sequencing services but also bioinformatics so the massive amounts of data generated can be analysed fully.

“As a Centre of Research Excellence we rely on NZGL to help us handle the large datasets and bioinformatics that drive our science. It is also incredibly useful to have someone you can talk to and work over results with.”

The research has attracted commercial partner interest and Professor Glare says the spray tests they are now doing are to test their efficacy in field situations.

Non-chemical pest control method showing exciting results

Research on using non-chemical methods to control potato pests is delivering groundbreaking results.

A newly published paper from the Biology Husbandry Unit (BHU) Future Farming Centre and Lincoln University, detailing the results of field trials, shows the use of a mesh cover over the plants was very effective in controlling tomato potato psyllid, or TPP, as well as reducing potato blight

One of the authors of ‘A field evaluation of the effectiveness of mesh crop covers for the protection of potatoes from tomato potato psyllid’, Dr Charles Merfield, says TPP can potentially cause severe crop loss due to phytotoxic saliva and transmission of the bacteria Candidatus Liberibacter Solanacearum.

The bacterium is believed to cause diseases such as ‘psyllid yellows’ in tomatoes and potatoes, and ‘zebra chip’ symptoms in potato tubers.

“The potential in the developed world to use mesh which is very safe, in place of chemicals, is very exciting,” Dr Merfield says.

The arrival of TPP in New Zealand led to potato, tomato and pepper growers increasing their frequency of insecticide use, which disrupted integrated pest management programmes that were already in place, he says.

Over two growing seasons in Canterbury, potatoes growing under mesh covers were found to have much reduced numbers of TPP nymphs and adults, increased tuber size, increased overall yield and enhanced storage potential compared to uncovered plots.

There had been no effective TPP controls for purely organic growers.

The mesh can also control a wide range of pests on many different field crops, for example, it is already being used by organic growers to control root fly on carrots, Dr Merfield says.

The mesh crop covers are made of monofilament plastics, such as polyethylene and polypropylene, woven in a plain weave. They form a barrier between insect and crop.

Dr Merfield says the mesh covers appear to be an ideal way of controlling TPP on potatoes and are preventative rather than curative like agrichemicals. However, there will be more work to validate the results for which funding is already in place.

Lincoln University Agricultural Sciences senior lecturer Dr Simon Hodge, another author of the paper, says mesh crop covers have been widely used in Europe for nearly two decades for control of a large number of pests, both insects and vertebrates on a wide range of crops.

Notice of hearing on fungi to protect cereal crops

The Environmental Protection Authority is holding a hearing to decide on an application to release non-toxic Epichloe fungi. Epichloe endophytes could improve the resistance of cereal plants to insect pests, fungal diseases and drought.

The EPA has previously approved the import and release of 45 strains of asexual Epichloe fungi. Grasslanz Technology Ltd has applied to add a further 18 strains to the approved list of endophytes.

The hearing will be held on Monday in the Lambton Room 1, at the Terrace Conference Centre, St John’s House, 114 The Terrace, Wellington. It will begin at 10am and is expected to adjourn around 2pm.

The hearing will focus on the benefits, risks and costs of the Epichloe fungi in new cereal-endophyte associations for applications in agricultural systems.

The EPA’s role is to oversee applications for new organisms under the Hazardous Substances and New Organisms Act. We assess the benefits, risks and costs of releasing new organisms to safeguard people and the environment.

You can read more about this application and the hearing process here on the EPA website.

Lincoln student in frontline of battle against stink bug

Lincoln University PhD student Laura Nixon is working on the development of a weapon in the fight to stop the brown marmorated stink bug coming into the country.

The bug is regarded by New Zealand’s horticulture industry as one of the top six pests of concern.

Ms Nixon’s research is funded through a multiorganisational research collaboration, Better Border Security (B3) and she is based at the Bio-Protection Research Centre on Lincoln’s Te Waihora campus.

Her aim is to come up with a way to chemically detect an infestation of the bugs in a confined space such as a shipping container, one of the ways it is envisaged the insect could make its way into the country.

The brown marmorated stink bug is an agricultural pest found in Asia, but it has invaded the United States and it is considered highly likely it could successfully establish in New Zealand if it gets here.

Since the insect arrived in the United States in the mid-1990s it has occasionally multiplied into plague proportions. In 2010 it caused US$37 million damage to apple crops across several states.

It feeds on more than 300 hosts, primarily fruit trees and woody ornamentals but also field crops. Almost any crop can be at risk.

Ms Nixon says the chemical compound, or the stink, the bugs emit when disturbed has been identified but she will work on trying to distinguish it from amongst other naturally emitted odours.

Initially she will work with native stink bugs, which are not considered pests, and then travel to the United States to see if her results can be used on the pest species.

She says the bugs are closely related so it is expected they will.

Ms Nixon says the bugs tend to live in big groups or aggregations, so if one container gets through then there could be a problem.

Hopefully her work will ensure it is stopped at the border, she says.

She says the method could be used to detect other insects such as ants and harlequin ladybirds which are also considered pests, though they present other challenges as they give of lower odour levels.

Her role involves developing the chemistry to the stage the odour can be detected and the commercial application may be undertaken by others.

Nominations sought for mentoring award

Applications are open for the Miriam Dell Award for Excellence in Science Mentoring.

This is the second time the award has been offered. The inaugural award was presented to Dr Judith O’Brien of the University of Auckland in 2013.

The Miriam Dell Award is awarded on a biennial basis to someone who demonstrates outstanding mentoring efforts to retain females in science, mathematics or technology.

Nominees can be from any part of the science system – including teachers at primary or secondary schools, lecturers or supervisors in tertiary education, or from commercial science-based organisations. They may have mentored, formally or informally, females at any stage in their career – from school age to the science workforce.

The award is named for Dame Miriam Dell, Patron of the Association for Women in the Sciences, botanist, secondary school teacher and advocate for women’s advancement.

“Encouraging women in science is incredibly important,” says Emma Timewell, National Convenor of AWIS.

“Having females across the science system provides a much-needed mix of viewpoints, skills and cultures that will allow New Zealand to excel in its endeavours. One of the key actions that supports this is ensuring females are adequately mentored at every stage of their career, from school to retirement. This Award acknowledges those mentors, particularly those who go beyond the call of duty to ensure girls and women are supported in meeting their scientific potential.”

Nomination forms and more information on the award are available on the awis.org.nz website.
Nominations for this year’s Award close on 30 June.

Female scientists eligible for inaugural $25,000 award

Australasia’s premier women in science award is expanding with the addition of a NZ$25,000 fellowship specifically for early-career female scientists in New Zealand.

In 2015 the L’Oréal Australia & New Zealand For Women in Science Fellowship programme comprises four $25,000 awards, three for Australian scientists and one dedicated to a Kiwi.

The addition of an inaugural dedicated New Zealand Fellowship boosts the total grants in Australia and New Zealand to around $100,000. Previously scientists from both countries competed for A$75,000 in grants.

The L’Oréal For Women in Science Fellowships have been open to New Zealanders only since 2012 when University of Otago, Christchurch, senior lecturer Dr Suetonia Palmer was awarded a fellowship.

Applications for the inaugural $25,000 L’Oréal New Zealand For Women in Science Fellowship are now open and close on 7 April.

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