NOTICIAS DEL SECTOR

Posted on Friday, 08.07.09 Recommend (0)shareemailprintcommentreprint .SOUTH MIAMI-DADE
South Florida avocado crops at risk of laurel wilt disease
Beetles from the north are carrying a disease that could wipe out South Florida's avocado industry.


Richard Lyons shows off one of his fresh Avocados. A tree-killing fungus has made its way down to Homestead from Georgia and is now threatening avocado trees countywide at Richard Lyons Nursery in Miami. CHRIS CUTRO / FOR THE MIAMI HERA / CHRIS CUTRO / FOR THE MIAMI HERA
Photo Similar stories:•Fast-moving fungus threatens South Florida avocado trees
Fast-moving fungus threatens South Florida avocado treesA tree-killing fungus has made its way down to Homestead from Georgia and is now threatening avocado trees countywide.
According state agriculture officials, the disease could harm South Florida's $12.7 million avocado industry and kill trees that have become a staple of Miami backyards.
Florida Department of Agriculture and Consumer Services spokesman Mark Fagan's description of the situation was grim and concise.

•Avocado trees threatened
Avocado trees threatenedThe Miami-Dade Cooperative Extension Division is alerting South Floridians about a fungus-carrying beetle that is on its way south from North Florida and poses a serious threat to avocado trees, and related species.
Look out for signs of rapid leaf wilting in avocado trees, which may be caused by the laurel wilt fungus.
The redbay ambrosia beetle, a non-native insect, carries and feeds off the laurel wilt fungus that kills avocado, redbay and other trees in the laurel family. While the beetle itself does not harm trees, the fungus it carries stops the flow of water in host trees, causing leaves to wilt and turn brown and the tree to eventually die.

•Tiny exotic beetles threaten Florida crops
Tiny exotic beetles threaten Florida cropsGuacamole lovers, beware: An Asian beetle half the size of a rice grain is spreading a fungus fatal to avocados and red bay trees and is working its way south, toward 6,500 acres of avocados in Miami-Dade County.
University of Florida researchers told the County Commission Tuesday they needed funding to find a way to eradicate the insects and disease before they reach commercial groves. The beetles have spread as far south as Okeechobee County.
Most of the state's commercial avocado groves -- a $12.7 million industry -- are in Miami-Dade and are so far untouched by the fungus, as is the national avocado collection at the USDA Subtropical Horticulture Research Station in Coral Gables. But scientists already know the damage it can do because it has killed many red bay trees -- a close relative of the avocado -- as it creeps south from Savannah, Ga., where it was discovered in 2002.

•Blueberry virus strikes Michigan research center
Blueberry virus strikes Michigan research centerThe bloom could be off Michigan's $124 million per year blueberry industry after two destructive viruses infected bushes in three locations.
Particularly upsetting to scientists is where one of the outbreaks occurred - Michigan State University's agricultural research station in southwestern Michigan. An outbreak of blueberry shock is forcing scientists to destroy plants that represent two decades and millions of dollars of research.
It will take years for new plants to mature so research can resume, said Annemiek Schilder, an associate professor of plant pathology and blueberry researcher. Still, she said, "We can't risk having that spread its way through Michigan's blueberry industry."

•Disease may threaten Florida's avocado crop
Disease may threaten Florida's avocado cropFlorida's avocado industry, the nation's second-largest, could lose millions of dollars if a new disease reaches Miami-Dade County, say University of Florida experts.
The state's avocado crop brings in about $30 million wholesale each year, according to the co-authors of a new paper expected to be published later this year.
Commercial avocados grow almost exclusively in Miami-Dade County, and about 60,000 Floridians have at least one avocado tree their yards, the UF researchers said.
BY JOSE PAGLIERY
jpagliery@MiamiHerald.com
Driving his burgundy-colored golf cart between rows of fruit trees inside his large grove, Richard Lyons spots a fallen avocado, its dark green skin shining in the afternoon sun.

Reaching for his phone, he calls one of several men who help maintain his plant nursery, located just northwest of Goulds.

``Juan, could you come? There are fallen avocados, and it would be a shame if they went to waste,'' he said in Spanish, then hung up.

``They will be salvaged,'' he said proudly.

If only the trees themselves were as fortunate.

Lyons and hundreds of growers in South Dade are worried that little will be left of their crops now that a wave of disease-carrying bugs has made its way to South Florida and threatens to wipe out avocados everywhere.

If the fungus spreads quickly, it could destroy the state's lucrative avocado industry, which makes up an estimated 6,500 acres of production in Miami-Dade County, according to the Florida Department of Agriculture and Consumer Services.

Gone would be an industry worth $12.7 million, according to a conservative estimate by state officials. Avocado growers contest that figure, valuing the crops closer to $40 million.

All of it could be destroyed by laurel wilt disease, a fungus that kills trees in the laurel family. A case of it was found in the county recently by scientists working with the University of Florida's Tropical Research and Education Center in Redland.

Included on the blacklist are redbay and avocado trees -- both susceptible to the fungus that infects the sapwood, restricts the flow of water and causes leaves to wilt.

The fungus is carried by the redbay ambrosia beetle, a tiny Asian insect that spreads the disease from its mouth. Federal and state agriculture experts have tracked its rapid movement south along Florida's east coast since 2005.

Trevor Smith, an entomologist with the state's agriculture department, is a member of the multiagency team attempting to halt the spread of the disease. They inspect fruit cargo, interstate shipments of wood and held public service announcements -- to no avail.

``It moved naturally,'' he said. ``It got into the natural ecosystem and it worked its way south. There was nothing anyone could do to stop it.''

Local growers kept a close eye on the spreading disease, which eradicated large swaths of redbay trees in Duval County after its appearance there in 2005.

On Wednesday, those who feared the bug would do the same in South Dade gathered at the John D. Campbell Agricultural Center only to receive grim news from UF researcher Randy Ploetz: The fungus is here.

Tree samples taken by researchers last week show that the disease-carrying insect is now present in the county, marking the first time laurel wilt has been found in an area of commercial avocado-growing.

For growers in Redland and Homestead, the discovery is tragic.

Delores Fox is a grower whose Redland home is surrounded by thousands of avocado trees. For the 63-year-old woman and her husband, the fruit trees have been their source of income since 1992's Hurricane Andrew tore their 2,500 seedless Persian limes from the ground and scattered them across the land.

Determined to continue farming, Fox and her husband planted avocados instead, braving the scorching sun and the thick, sizzling humid air. It took them five years to start making revenue.

Nearly two decades later, tiny beetles now threaten to match the destruction that the historic Category 5 storm once did to Fox Farms.

``The potential is there to decimate a livelihood,'' Delores said. ``You're going from a dollar sign to zero -- and you have to go into the negative because you have to pay taxes and disposal fees.''

The industry includes hundreds of growers, packers, farm hands, landscapers and transport companies that rely on the yearly avocado crops. The disease is catching them all in the midst of a recession and a lousy crop year, as rising costs and light yields have halved their incomes.

Making matters worse: The disease is hard to spot and difficult to stop from spreading.

Signs of infection -- such as the appearance of dead, dry and curled leaves -- mimic the aftermath of lightning hitting a tree.

``This pathogen is a brand-new science,'' Ploetz told growers on Wednesday. ``We are now threatened with some serious problems.''

Tree owners everywhere are urged to stop pruning, hedging and topping their avocado trees because the infected bugs can cling to mechanical equipment. That equipment should be disinfected and trees should be checked regularly, Ploetz warned.

State officials are urging county residents to not transport any avocado, sassafras, redbay, swamp bay, pondberry or pondspice trees unless they are purchased directly from a registered nursery.

Owners of those trees should also watch for leaves that change color from light green to dark green to brown, which is one sign of infection. Other signs include the appearance of small holes on the bark and dark streaks in the sapwood.

If a tree turns out to be infected, the only remedy is to burn it, a process that requires a permit from the county's department of environmental resources management.

However, residents who suspect that their trees may be infected are urged to first contact the state's Division of Plant Industry, which will take samples in order to further advise any worried commercial avocado growers.

The agency can be reached at 1-888-397-1517.