The University of Idaho recently received a grant for research in eradicating a nematode that attacks potato plants in Idaho.
The $436,529 grant is from the U.S. Department of Agriculture National Institute of Food and Agriculture. The project will focus on finding alternative ways to eradicate the nematode — Globodera Pallida. Currently methyl bromide is the primary chemical used to eradicate the nematode.
The pest was first found in Idaho in 2006 and has only ever been in Idaho, said Director of the PCN Project, Louise-Marie
Dandurand.
The nematode only attacks potatoes and can cause an 80 percent yield loss, she said. Management of the nematode is regulated by U.S. Department of Agriculture, Animal and Plant Health Inspection Service (USDA-APHIS) and the Idaho State Department of Agriculture.
“Their main objective for this nematode is to eradicate it, to get rid of it in potato fields in southern Idaho,” Dandurand said.
Currently there are about 2,000 acres of potatoes in southern Idaho infested with the nematode, and about 14,000 acres that are being managed, she said. Many of the fields are not infested with the nematode but they are still managed and tested a couple times a year by the USDA-APHIS because by proximity the plants could receive the infection.
“They (USDA-APHIS) fumigate with methyl bromide but it is being phased out worldwide because it is a fumigant that can cause a lot of environmental problems, such as damaging the ozone layer,” Dandurand said.
The grant addresses a couple alternative ways to reduce methyl bromide and eradicating this nematode, she said.
The PCN Project is proposing to solve the problem by using a trap crop, also known as the litchee tomato, she said.
The nematode survives in the soil through a cyst which looks round and leathery, Dandurand said. These cysts can fall off the potato root and remain in the soil where they can live and reproduce for 20 to 30 years. Within the cyst, there are a number of eggs that hatch when there is a chemical stimulant that is released by the roots of the potatoes. Once the eggs hatch the nematode worms swim through the roots and infect the entire potato plant.
The trap crop produces a chemical stimulant that is called a hatching factor, when released it causes the nematode to hatch,
she said.
“What is different about it is that this trap crop doesn’t allow the nematode to reproduce,” Dandurand said. “So it will hatch but they won’t reproduce so it will eventually decrease the population.”
A problem that has arisen with the trap crop is all the eggs in the cyst will not hatch at the same time, she said. To increase efficiency of the trap crop the PCN Project is introducing a fungal biological control agent that would attack the eggs.
The two fungal biological control agents have a history of good control against the nematode by eating the eggs,
Dandurand said.