Understanding apples' ancestors

Dec 11, 2009
Researchers study wild Malus orientalis in the Caucasus region. Credit: Photo by Phil Forsline

Wild Malus orientalis -- species of wild apples that could be an ancestor of today's domesticated apples -- are native to the Middle East and Central Asia. A new study comparing the diversity of recently acquired M. orientalis varieties from Georgia and Armenia with previously collected varieties originating in Russia and Turkey narrows the large population and establishes a core collection that will make M. orientalis more accessible to the breeding and research communities.

To identify and record the genetic diversity of these wild apples, Gayle Volk and Christopher Richards at the National Center for Genetic Resources Preservation, U.S. Department of Agriculture (USDA), performed genetic diversity analyses on grown from Malus orientalis seeds collected in Georgia, Armenia, Russia, and Turkey. The trees are located at the USDA-ARS Plant Genetic Resources Unit (PGRU) in Geneva, New York. Seedling trees were evaluated for resistance to critical diseases such as fire blight, , and cedar apple rust. The full report was published in a recent issue of the Journal of the American Society for Horticultural Science.

Seeds from wild Malus orientalis trees were collected from 1998 during explorations to Armenia, Georgia, Turkey, and Russia. Seedling orchards with between eight and 171 "individuals" from each collection location were established, and data were collected for 776 trees. The of the 280 individuals from Armenia and Georgia was compared with results obtained for individuals from Russia and Turkey. A total of 106 alleles were identified in the trees from Georgia and Armenia. The average gene diversity ranged from 0.47 to 0.85 per locus. The researchers concluded that "the genetic differentiation among sampling locations was greater than that found between the two countries."

Six individuals from Armenia exhibited resistance to fire blight, apple scab, and cedar apple rust. According to Volk; "The data suggest wild populations of M. orientalis from regions around the Black Sea are genetically distinguishable and show high levels of diversity."

A core set of 27 trees that captures 93% of the alleles in the PGRU M. orientalis collection will be maintained in the field at the PGRU in Geneva, New York.

More information: The complete study and abstract are available on the ASHS Journal of the American Society for Horticultural Science electronic journal web site: journal.ashspublications.org/c… t/abstract/134/4/453

Source: American Society for Horticultural Science

Explore further: From dandruff to deep sea vents, an ecologically hyper-diverse fungus

add to favorites email to friend print save as pdf

Related Stories

Conserving historic apple trees

Nov 04, 2009

The apple trees of yesteryear are slowly disappearing. Many apple varieties common in the United States a century ago can no longer be found in today's orchards and nurseries. But some historic apple trees ...

Scientists Cryopreserve Pest-Imperiled Ash Trees

Oct 28, 2009

(PhysOrg.com) -- Using cryopreservation methods, Agricultural Research Service (ARS) scientists have devised a procedure for storing frozen budwood from ash trees (Fraxinus) and thawing the delicate buds for ...

'TRAP' preserves genetic properties of popular geranium

Nov 05, 2007

Reseachers at The Ohio State University have demonstrated that Target Region Amplification Polymorphism, or TRAP, is an effective method for preserving the important genetic diversity of ornamental flower collections.

Recommended for you

Of bees, mites, and viruses

8 hours ago

Honeybee colonies are dying at alarming rates worldwide. A variety of factors have been proposed to explain their decline, but the exact cause—and how bees can be saved—remains unclear. An article published on August ...

Genetically tracking farmed fish escaping into the wild

Aug 20, 2014

European sea product consumption is on the rise. With overfishing being a threat to the natural balance of the ocean, the alternative is to turn to aquaculture, the industrial production of fish and seafood. ...

France fights back Asian hornet invader

Aug 20, 2014

They slipped into southwest France 10 years ago in a pottery shipment from China and have since invaded more than half the country, which is fighting back with drones, poisoned rods and even chickens.

User comments : 0