New tool predicts risk of plant disease

A newly developed technique can predict the risk of plant disease or infestation across the globe. Described in open-access journal Frontiers in Applied Mathematics and Statistics, the technique considers pest-host interactions and the geographical distribution of vulnerable plants to provide maps of potential disease hotspots. This could help governments to understand the risk of outbreaks before they happen.

Diseases and pests can have a devastating impact on plants, the surrounding ecosystem, and food supplies. These effects can be particularly damaging when a pest or pathogen invades a new territory, in which native plants have little natural resistance and the destructive invader has few native predators or competitors. Continue reading

Repellent emitted by redbay may be key to fighting beetles

in Growing Produce

by Paul Rusnak, Growing Produce

UF/IFAS scientists might have just tracked down the right scents to help deter a beetle that’s been delivering disease and devastation to Florida avocado growers.

According to a recently published study, UF/IFAS researchers found when infected with the laurel wilt fungus, redbay trees (a close cousin to the avocado) emit methyl salicylate to repel redbay ambrosia beetles, the vector of the deadly pathogen. Continue reading

Invasive insects turn forests into wasteland

by Michael Casey and Patrick Whittle, Associated Press

In a towering forest of centuries-old eastern hemlocks, it’s easy to miss one of the tree’s nemeses. No larger than a speck of pepper, the Hemlock woolly adelgid spends its life on the underside of needles sucking sap, eventually killing the tree.

The bug is one in an expanding army of insects draining the life out of forests from New England to the West Coast. Aided by global trade, a warming climate and drought-weakened trees, the invaders have become one of the greatest threats to biodiversity in the United States. Continue reading

Biology, Ecology, and Management of Laurel Wilt in the Southeastern U.S.

This webinar will discuss biology, ecology, and management of laurel wilt, a disease caused by the fungus Raffaelea lauricola) and disseminated by the redbay ambrosia beetle (Xyleborus glabratus). The webinar is being put on by the Southern Regional Extension Forestry.

This webinar is designed to help woodland owners, foresters, researchers, and concerned citizens to learn how to identify laurel wilt disease in the forest and residential landscape.  This disease impacts several woody plant species, mostly in the Family Lauraceae.  In addition, the webinar will describe the disease biology, susceptible hosts and current management options. Click for more information. Continue reading

Scientists find possible biological control for redbay ambrosia beetle

Scientists at the University of Florida have discovered a few fungal biological control options that show promise for fighting the redbay ambrosia beetle. They discuss the results of their experiments in a refereed article in Biological Control.

The redbay ambrosia beetle (RAB) was first discovered in southeast Georgia in 2002. A native of Asia, the beetle transmits a pathogen that causes laurel wilt, a disease that can kill an infected tree in just a couple of years. The beetle attacks trees in the family Lauracea, which includes redbay, swampbay, sassafras and avocado.

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Laurel wilt confirmed in Louisiana sassafras trees

Laurel wilt, a devastating disease of a number of Louisiana trees in the Lauraceae family, has recently been confirmed in sassafras trees in Union Parish.

The disease is caused by a fungus that clogs the water-conducting tissue of the tree. As a result, the affected tree wilts and eventually dies, according to LSU AgCenter “Plant Doctor” Raj Singh.

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SIPMC Funds 11 IPM Enhancement Grants this year

Home gardeners, farmers and others will have new tools and educational opportunities thanks to 11 projects recently funded by the Southern IPM Center. Out of a total of 20 proposals, these 11 projects, totaling $300,000 in funding, will provide new crop profiles on turfgrass, ornamentals and agricultural crops; delve into complex pest issues with avocadoes, sorghum and other crops; and provide information for home gardeners on how to use IPM in small vegetable gardens.

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Research indicates new hosts for two major plant diseases

The Plant Management Network highlights two research projects this month that have uncovered new possible hosts for two deadly forest diseases: laurel wilt and Phytophthora ramorum.

Vectored by the redbay ambrosia beetle, laurel wilt attacks species in the Lauraceae family, causing death within a few years. Recently, scientists tested Persea indica, a tree species native to the Madeira and Canary Islands, for its attractiveness to the redbay ambrosia beetle. The beetle preferred P. indica over Persea borbonia (redbay), its primary host in the U.S.

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Beneficial Fungi Examined for Battle against Destructive Beetles

In ARS News

An experimental foam containing insect-killing fungi is being tested by U.S. Department of Agriculture (USDA) scientists in the fight against ambrosia beetles, wood-boring pests that threaten the nation’s $322 million avocado crop.

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ARS Scientists Devising New Ways to Protect Avocados

U.S. Department of Agriculture (USDA) scientists are coming up with new strategies to combat a beetle threatening the nation’s avocado trees.

Laurel wilt disease is caused by the fungus Raffaelea lauricola, and is vectored by the redbay ambrosia beetle, an invasive pest from Asia that has spread to the Carolinas, Florida and west to Mississippi. The disease kills 90-95 percent of infected trees. Scientists are concerned that it will soon reach Mexico and California, which are major avocado production areas. Its victims also include several other types of laurel trees.

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