Indigenous fungus may help to control wilding pines

An indigenous New Zealand fungus may help to control wilding pines – one of the country’s most ecologically damaging weed species – a student’s research project shows.

Wilding pine control costs New Zealand millions of dollars a year and involves the costly and time-consuming methods of cutting down the trees and spraying herbicide from the air. Control seldom totally eradicates the pines, which often reinvade sites some years later.

Armillaria novae-zealandiae, also known by Māori as harore, is a fungus that feeds on decaying wood. It is common in native forests, where it is a natural part of the ecosystem, helping to decay fallen trees. But if it gets into pine plantations it is seriously destructive, killing seedlings and reducing growth.

In a Bio-Protection Research Centre student research programme, biology student Genevieve Early investigated how well A. novae-zealandiae and two closely related species established on wilding pine species.

Supervised by BPRC principal investigator and University of Canterbury Professor Ian Dickie and his colleague Dr John Pirker, she tested what age of wood it grew best on (ranging from live and freshly harvested wood to old and decayed wood). Continue reading

Native plants may be weapon against soil contamination

New Zealand’s native plants may help to reduce bacterial contamination caused by dairy effluent, a new study suggests.

Researchers from the Bio-Protection Research Centre, ESR, and the University of Canterbury have shown northern rātā (Metrosideros robusta) and swamp mānuka (Leptospermum scoparium) can reduce the amount of Escherichia coli (E. coli) in soil by 90%, compared with ryegrass (Lolium perenne), and in less than one-third of the time. They worked in partnership with Ngaa Muka Development Trust and Matahuru Marae in Waikato.

The research, published in Applied Soil Ecology, aimed to investigate the antimicrobial properties of New Zealand native plant extracts and test if they were effective in soil. Continue reading

Distinguished Professor Steve Wratten notches PhD supervision milestone

Professor Steve Wratten, the recipient of many awards in an illustrious academic career that has spanned almost five decades, is about to notch up another remarkable milestone.

When Lincoln University PhD students Emiliano Veronesi and Joel Faulkner achieve their PhD qualifications, they will be the 89th and 90th PhD students to have been supervised by Professor Wratten during their doctorates.

He will have guided those 90 PhD students through at least an accumulated 270 years of doctoral study.

Beginning his academic career as a lecturer in Zoology at London University in 1971, Professor Wratten moved to Cambridge University in 1972, lecturing in Applied Entomology. In 1975 he joined Southampton University as a lecturer in Biology, where he first supervised PhD students.

He moved to New Zealand and Lincoln University in 1993 and has become a Distinguished Professor of Ecology in the Bio-Protection Research Centre, hosted at Lincoln University. Continue reading

Lincoln makes several courses free to help maintain NZ’s food and fibre trade advantage

Lincoln University is offering fee waivers for a number of its post-graduate qualifications  – but only for domestic students – essentially making the courses free except for some student levies.

The aim is to meet the food and fibre sector’s need for skilled and qualified workers, as it benefits from a trade advantage identified by Lincoln experts.

Professor Stephen Goldson, Deputy Director of the Lincoln-based Bio-Protection Research Centre, and Dr Caroline Saunders, Director of the Agribusiness and Economics Research Unit at Lincoln University, said in an article on the Centre’s website New Zealand is one of a small group of countries which have been international beacons of hope, through protecting their citizens with science-based responses to the new virus.

“That admiration is translating into a trade advantage for our primary sector exporters.” Continue reading

New Zealand is losing the war against weeds

New research* highlights how the lack of success in controlling weeds on agricultural and conservation land is challenging New Zealand’s position as a global leader in biosecurity.

Weeds are costing the country billions of dollars every year.

In a state-of-the-art review of how weeds are managed in New Zealand, Professor Philip Hulme has called for a paradigm shift in our approach.

“Unfortunately, we have rather little to show for the vast amount of time and effort government and landowners invest in the management of weeds,” said Professor Hulme, of the Bio-Protection Research Centre based at Lincoln University. Continue reading

Study shows pathogens lurking in farm and forest soil

Science has revealed for the first time what microbes are lurking in our soil – and that there are many more harmful ones on farms and in plantation forests than in natural forests.

In his PhD research with the Bio-Protection Research Centre, based at Lincoln University, and Manaaki Whenua – Landcare Research, Andi Makiola studied how land uses such as farming and plantation forestry affected the variety of plant pathogens in the soil and on plant leaves and roots.

Pathogens are organisms that can cause plant disease.  They include fungi, bacteria, and oomycetes (for example, Phytophthora agathidicida, which causes kauri dieback).

Dr Makiola and colleagues used a new method called next-generation sequencing to extract and amplify DNA from soils and plants across New Zealand, revealing what plant pathogens lived in them.
Continue reading

Exotic insects found in NZ are not known in their home countries

The discovery and description of two new insects suggests  New Zealand may be home to more exotic insects than those we know about.

Scientists from the Bio-Protection Research Centre have described and named two new exotic insects present in New Zealand that weren’t previously known about – not even in their native countries.

A paper published in the journal PLOS ONE, written by former Bio-Protection Research Centre PhD student Francesco Martoni and BPRC senior research scientist Dr Karen Armstrong, describes two psyllids (also called jumping plant lice), Acizzia errabunda and Ctenarytaina insularis.

These extremely small insects, no more than 3 mm long, are not easy to detect. Continue reading

Lincoln professor is honoured for science communication

Professor Steve Wratten, a Principal Investigator at the Bio-Protection Research Centre and Professor of Ecology at Lincoln University, has won the John Taylor Award for leadership in horticulture.

The award from the Canterbury Horticultural Society was given for his ability to communicate complex ideas to the non-scientific community.

“In doing so, people have become empowered to make a difference at a local level, which in time becomes regional, national and international,” his citation reads.

“His research and dissemination of knowledge to horticulturists and gardeners has and will continue to enable people to follow his lead and improve our production systems.”

Professor Wratten, a Fellow of the Royal Society Te Apārangi, specialises in biological control of pests. He advocates using companion planting to provide SNAP (Shelter, Nectar, Alternative food, and Pollen) for the natural enemies of insect pests.

He used this method to develop the Greening Waipara programme, which uses native plants to control pests and increase biodiversity in North Canterbury vineyards.

Accepting the award, Professor Wratten said university researchers had to produce both outputs, such as scientific publications, and outcomes, which were about making a difference – in this case to gardeners and professional horticulturalists.

Source:  Bio-Protection Research Centre

Sundar helps change Nepalese agriculture

PhD student Sundar Tiwari’s PhD research is helping to change the face of Nepalese agriculture.

Sundar, who comes from a rural Nepalese village, did his BSc and MSc in agricultural entomology at Tribhubhan University, Nepal. He works as an assistant professor at the Nepal Agriculture and Forestry University, focusing on integrated pest management

With the help of a PhD scholarship from New Zealand’s Ministry of Foreign Affairs and Trade, Sundar joined the Bio-Protection Research Centre at Lincoln University in 2016 and began research into sustainable intensification of Nepalese agriculture.

In his New Zealand-based research Sundar is seeking an alternative approach to pest management, looking to identify “trap plants” that can draw the wheat bug (Nysius huttoni) away from kale seedlings.

His experiments show that the popular garden plant alyssum (Lobularia maritima) has the highest potential as a trap plant for the bug, and it also provides many other ecosystem services (such as providing nectar for beneficial insects).

Working in Nepal on radish crops, he showed how to reduce aphid populations without pesticides, using alyssum flower strips around the fields.

“This technique is very simple and poor farmers can easily adopt it, especially because it costs less than using pesticides,” Sundar says.

Sundar has introduced many Nepalese farmers, students, and others in the agriculture sector to the concept of habitat management and multiple ecosystem services, and his work is influencing Nepalese agricultural policy.

“This work in my home country has made a real difference and is one of the many factors which have made my PhD training at Lincoln University so enjoyable,” he says.

Sundar’s supervisor is Professor Steve Wratten; his co-supervisor is Professor Nick Dickinson.

Source:  Lincoln University

Pine and pasture may harbour kauri dieback

The Government should be cautious about planting pine near northern kauri forests because research suggests they may act as reservoirs for kauri dieback, says an expert in the disease.

Dr Amanda Black, of the Bio-Protection Research Centre, says pine plantations and agricultural pasture may have a role in incubating and spreading the disease – as revealed by research for a Master’s thesis, completed by her student, Kai Lewis.

But at the same time, the Government is promoting an increase in commercial forestry – including radiata pine – as part of its 1 billion trees programme.

“We urgently need further research to clarify the role pine forests, pasture, and other plants play in incubating and spreading Phytophthora agathidicida – the organism that causes kauri dieback,” says Dr Black, who supervised the study and thesis by Mr Lewis.

“Until we are sure of what role they play, we should be very careful about planting any further pine plantations anywhere near kauri forest.”

For his thesis at Lincoln University Mr Lewis studied how well P. agathidicidareproduced in three types of soil: kauri forest, pasture, and pine forest. He collected samples near Waipoua Forest in Northland and one of the original mainland sites from which kauri dieback has spread.

Results showed that in its early stages of development P. agathidicida reproduces much more rapidly in pine forest and pasture soil than it does in kauri forest soil. In pine forest soil it also produces more long-lived spores (oospores).

Other research reported earlier this year showed P. agathidicida infected other native plants, including tanekaha, suggesting more potential hosts need to be examined.

Mr Lewis’s research also showed that P. agathidicida could infect Pinus radiata and several common pasture plants, even those that show no symptoms. This suggested other plants and soil may act as a reservoir for P. agathidicida.

“This raises the possibility that kauri dieback may be moving from pine plantations and pasture into kauri forests, carried by people, animals, and even on machinery,” says Dr Black.

“We urgently need further research to find out if this is happening and how. Until we know the answer, we need to be very careful.”

In his thesis Mr Lewis said investigating the role of unfenced pasture next to kauri forests was a high priority for further research.

He also found two other species of Phytophthora (P. pini and P. gregata), which can infect several plant species, were present in kauri forest and pasture soils. Their possible role in infecting native trees is another high priority for further research.

A paper submitted to an academic journal as a result of this research is under review. Another is about to be submitted.

One of the papers outlines the discovery of the two new species of Phytophthora in New Zealand, the other looks at the effects of fragmented landscapes on the growth and survival of P. agathidicida.

The full thesis from Lincoln University’s Research Archive can be downloaded HERE.

Source: Bio-Protection Research Centre