Grape Crop Germplasm Committee Genetic Vulnerability Statement
November, 2001
Enhanced governmental funding is needed to upgrade and strengthen the National
Clonal Germplasm Repository (NCGR) system. The Davis and Geneva centers need
to lead and direct efforts on grape germplasm characterization, acquisition,
maintenance and distribution. Grape is the most valuable horticultural crop
in the world and the US, yet its germplasm resources are only modestly supported.
Because permanent and consistent support is required for the preservation and
maintenance of a collection of such high importance, it is essential that this
responsibility be borne at the federal level by the US Department of Agriculture.
The Grape Crop Germplasm Committee has met several times to discuss grape germplasm
vulnerability and needs. We have also considered the severe and imminent threat
that Pierce's disease poses to the Grape Industry and the Davis Repository.
The following recommendations will protect the Davis Repository, greatly enhance
the utility of the current collections, and promote germplasm research to correct
deficiencies.
· Immediately construct screen-houses at the Davis Repository to house
Vitis vinifera accessions and prevent their loss due to the potential
spread of Pierce's Disease by the glassy-winged sharpshooter.
· Complete a comprehensive characterization of the NCGR collections
including passport information, and morphological and molecular characterization.
Continue to collect, maintain, and distribute accessions.
· Develop and utilize tools to evaluate genetic diversity within Vitis
so the need for additional acquisition can be evaluated.
· Vitis germplasm from Asia, Mexico, Central America and the
Middle East carry the highest priorities for collection.
· Assess the diversity, range and taxonomic relationships of all Vitis
species. Respond by collecting endangered and under-represented germplasm, and
revising collection priorities as needed.
· Complete a thorough analysis of grape germplasm that are threatened
by habitat loss and abandonment of national and international breeding programs
and collections. Respond by collecting endangered and under-represented germplasm.
· Evaluate the NCGR collections for completeness and begin systematic
re-collection of species from North American regions to include a broad representation
of genetic variation both within and among species. Few of the species collections
in the NCGR system have adequate passport information, which inhibits their
rational use.
· Enhance access at the national and international level to plants and
databases and develop a national germplasm database of repositories, herbaria
specimens, and breeding collections.
· Develop cryopreservation and/or other methods to store grape buds,
seeds and pollen.
· Provide leadership to harmonize grape certification within and among
the various States, and participation in the development of international standards
for grape germplasm exchange.
· Facilitate the safe importation of grape germplasm for evaluation
and utilization through revision of importation restrictions on materials destined
for the NCGR stations.
· Encourage and develop interactions between breeders and germplasm
experts to enable the above needs.
National and International Grape Germplasm Organizations: Background and Statistics
Grapes are one of the most widely planted and economically successful crops
in the United States. California is the most important producer of grapes and
wine in the nation with almost 1,000,000 acres in production. Washington, New
York and Oregon complete the top four producers with about 100,000 acres altogether.
Given the importance and different needs of grape production in the various
states it is not surprising that there are two National Clonal Germplasm Repositories
(NCGR), one in Geneva, NY and the other in Davis, CA, and three USDA grape breeders
(Geneva, NY [2] and Fresno, CA [1]). In addition to these national efforts there
are public grape breeding and genetics programs at the University of California,
Davis; Cornell University, Geneva; the University of Minnesota; the University
of Arkansas, Fayetteville; University of Georgia, Tifton; and Florida Agricultural
and Mechanical University, Tallahassee. Many other publicly supported grape
breeding programs have been discontinued including those in: Florida, Illinois,
Maryland, Missouri, Virginia, and British Columbia. At least four private grape
breeding programs emphasizing development of fresh market grapes operate in
California. Several other private corporations are utilizing genetic engineering
and other tissue culture approaches to develop improved grape cultivars. There
are also numerous research programs across the country focused on germplasm
evaluation, cultivation, and pest control.
There are a variety of public advisory and regulatory organizations that affect
grape germplasm. The Grape Crop Germplasm Committee is made up of public and
private grape breeders, geneticists, pathologists, entomologists and viticulturists
and was established to advise the national plant germplasm system. The North
American Grape Breeders group is composed of breeders and geneticists, both
public and private, from across the country and has direct input into the CGC.
At a national level, the Bureau of Alcohol, Tobacco and Firearms (BATF) regulates
the sale of wine and naming of wine grape cultivars. Across the country, state
agencies are in charge of regulating their industries. Within California there
are two agencies with grape responsibilities. The California Department of Food
and Agriculture (CDFA) regulates the grape certification program, the nursery
industry, and growers with responsibilities directed at pest control and the
sale of grapes. The Foundation Plant Materials Service (FPMS) is a service branch
of the University of California, Davis responsible for providing certified plant
material (disease tested and true to variety) to the grape nurseries. FPMS is
also the site of the National Grape Importation Program (NGIP), a program sanctioned
by the USDA Animal and Plant Health Inspection Service (APHIS) to import grape
germplasm. Whereas APHIS regulates importation of germplasm from overseas, the
Dept. of Agriculture in each state regulates interstate movement of grapevines.
There are international organizations that have interest in cataloging and
preserving the world's grape collections. The International Plant Genetic Resources
Institute (IPGRI) has addressed grape germplasm issues in the past and voiced
its concern for the conservation and documentation of grape species and collections,
and their coordinated description (http://www.ipgri.cgiar.org/). The Office
International de la Vigne et du Vin (OIV) is an international body that oversees
wine and grape issues. Its primary focus is on international trade, including
trade in germplasm. A major contribution to the world's grape germplasm was
made by Alleweldt and Dettweiler who compiled world collections and grape authorities
in "The Genetic Resources of Vitis", which documents the genetic
and geographic origin of grape cultivar names and synonyms (http://www.dainet.de/genres/idb/vitis
and http://www.dainet.de/eccdb/vitis). This document was a monumental undertaking
and points to the continued need to identify and document not only cultivar
names, but also places where grape germplasm is maintained.
Most important cultivated grape cultivars are Vitis vinifera. They make
up not only the majority of U.S. plantings, but are also the dominant cultivars
in the world. Vitis vinifera cultivars are widely regarded as having
the highest quality for fresh and dried fruit and wine production. The world's
grape acreage was listed at 7,453,269 acres in 2000 (FAO Statistical Service);
about 98% of these acres are V. vinifera cultivars. However, these cultivars
possess few of the resistance genes needed to defend against a host of biotic
and abiotic stresses that confront viticulture around the world. Fungicides
and pesticides effectively control many of these problems, but environmental,
safety and economic concerns are beginning to limit the utilization of these
products. Resistance from other species will have to be utilized. Solutions
to environmental stresses such as cold, air pollution and soil problems will
depend on utilization of other germplasm.
The recent introduction of the glassy-winged sharpshooter into California,
and its potential to dramatically expand and intensify Pierce's Disease (PD)
in this State (see http://plant.cdfa.ca.gov/gwss/ and http://www.aphis.usda.gov/oa/pubs/fsglassy.html)
dramatically highlights the importance of the Nation's grape repositories. This
bacterial disease is native to the southern U.S. and breeders have been developing
new selections and cultivars for many years in efforts to combat PD. Many resistant
species and breeder selections exist at the Davis Repository and are being utilized
by the University of California, Davis and USDA Fresno grape breeding programs.
These sources of resistance are critical to breeding efforts focused on cultivar
development and identification of resistance genes.
The Davis Repository also houses one of the world's most extensive collections
of V. vinifera cultivars all of which are susceptible to PD. Given the
tremendous importance of grape to the economy of California, and the key role
of the Davis Repository in maintaining a world-renown V. vinifera collection,
it is essential that screenhouses be constructed at the Davis Repository to
protect this collection before the inevitable spread of the glassy-winged sharpshooter.
Pierce's Disease is limited by cold winter temperatures, as is the cultivation
of V. vinifera. However, V. vinifera survive lower temperatures
than does PD. Research into the range of PD needs to be encouraged and evaluated
in the event that the Davis Repository needs to be relocated to a colder region
of the State.
A collaborative research project on crown gall disease has been underway for
a number of years at the Geneva Repository. This bacterial disease, caused by
Agrobacterium vitis, results in galls capable of girdling trunks and
killing vines. The disease cycle is initiated as tumorigenic genes from the
bacteria's plasmid are incorporated into grape cells. Galling is induced after
trunks are damaged by cold weather, severe pruning or equipment. Because the
bacterium is systemic in grape and easily transmitted by herbaceous and woody
cuttings, this disease is often nascent until some form of tissue damage occurs.
The Geneva Repository collection has been surveyed and resistance to this disease
has been identified in accessions of V. amurensis, V. riparia, and various
interspecific hybrids. Examinations of the breadth of resistance and efforts
to characterize the inheritance of resistance and the genes involved continue.
The soil-borne pests that attack grape, including the root aphid phylloxera
and a range of nematodes, are controlled with resistant rootstocks. However,
pest populations change and the choice of resistant rootstocks with resistance
to multiple pests is limited. Fortunately, there are many sources of disease
and pest resistance among the Vitis species. Some of these resistant
species and traits have been utilized for over 100 years while the resistance
of other species is known, but has not been exploited. Perhaps as many as 60
grape species exist and relatively few have been utilized in grape breeding.
This germplasm represents tremendous genetic diversity and in many cases is
threatened by habitat loss.
The main charge of the Grape CGC is to advise and assist the NCGR curators.
However, this group also plays an important role in the National Plant Germplasm
System given their expertise in grape germplasm, its utility, and its vulnerability.
It is this latter area that this document addresses.
Grapevine Species: Important Traits and Vulnerability to Loss
Vitis vinifera is by far the most important grape species world wide,
although it could be argued that the species used in rootstocks are at least
as important, and without these, V. vinifera culture would be extremely
restricted. Vitis vinifera originated in the Middle East and spread with
the aid of birds and human migration across northern Africa to northern Europe.
Vitis vinifera has one subspecies V. vinifera spp. sylvestris
that is found in north Africa, and in widely scattered regions from Germany
to Spain and across to Eastern Europe. However, these populations are very rare
and have been declining due to introduced foliar diseases such as downy and
powdery mildew, and to the introduced grape phylloxera. It is often difficult
to separate the remaining populations of V. sylvestris from feral vines
or local land races; however, true V. sylvestris and land races both
are likely sources of important genes. Among these are better cold hardiness
in northerly accessions, shortened growth cycle in accessions from higher elevations,
and other climatically conditioned traits.
The world's native grape habitat is threatened in all areas of its range. Expanding
populations and agriculture have eliminated large expanses of habitat, and political
instability and economic decisions have limited both habitat and critical germplasm
collections. A key example of such potential loss was the collapse of the Soviet
Union and the inability of local governments to continue to fund some of the
most important collections of grape and other perennial fruits. These collections
were founded by Vavilov, the source of the key grape germplasm collections in
Crimea and Turkmenistan. There are many other important collections of grape
cultivars around the world with the primary ones located in Montpellier and
Pont-de-la-Maye, France; Geilweilerhof, Germany; Bet Dagan, Israel; Bari, Italy;
and Merbein, Sunraysia-Irymple and Victoria, Australia.
The collection of Vitis vinifera from its Middle Eastern center of origin
is of extreme importance given the tremendous genetic diversity still present.
Among the vinifera grapes from the Middle East are regional cultivars, distinctive
clones, and land races found no where else. Although this region is not known
for its wine grapes, it is a center for table and raisin grape production. Worldwide
table grape production is a major horticultural industry. In California there
are about 80,000 A of table grapes producing crop valued at about $1 billion.
The vast majority of California table grapes are seedless and the seedlessness
in these cultivars originates from a very narrow genetic base; primarily Thompson
Seedless (Sultanina or Kishmish in the Middle East, and Sultana in Australia),
an ancient Middle Eastern grape. Collections from this region are likely to
have other alleles for seedlessness that might reside in genetic backgrounds
with larger berries, different phenological traits, skin color, and flesh texture
- all traits growers and breeders desire.
Cultivars from this region may also have resistance or tolerance to a number
of diseases, pests and environmental conditions. Fanleaf degeneration is the
world's most serious grape viral disease. Fanleaf is caused by grapevine fanleaf
virus (GFLV) and spreads through the soil by the feeding of the dagger nematode,
Xiphinema index. This disease causes a slow vine decline, but is considered
serious because GFLV interrupts normal berry set and can eliminate fruit harvests.
Fanleaf degeneration originated in the Middle East and therefore, sources of
resistance to GFLV and perhaps its nematode vector should be found here. The
origin of other grape viruses is less well understood; however, it is likely
that others also co-evolved with grape in the Middle East, and resistance to
these may also be found there.
Middle Eastern Vitis vinifera cultivars may also possess other desirable
traits, drought and salinity tolerance being key among these. This species is
regarded as one of the most drought tolerant, having evolved in a very arid
region. Drought tolerance is becoming an increasingly important trait in rootstocks.
The world's population pressures will likely force viticulture into more xeric
areas and require rootstocks to have better forms of drought tolerance. The
form of drought tolerance that currently exists in rootstocks is adaptive -
these rootstocks survive because of their very large foraging root systems.
When soils are fertile or water supply is adequate such rootstocks promote excessive
vigor in scions. Middle Eastern V. vinifera may possess actual drought
tolerance whereby the roots are capable of surviving very dry soil without producing
a huge root system.
Asia is another center of origin for Vitis species. However, there is
little known about Asian grape species because most of the literature is in
Chinese and is largely unavailable outside of Asia. Accounts of the number of
Asiatic species range from about 10 to more than 50. They inhabit many areas
of China from the dry southwest, the foothills of the northern and southern
side of the Himalayas, the very cold northeast near Korea and the hot and humid
southeast. Chinese cultivars based on V. amurensis are grown in the northeast
of China. These cultivars have relatively large berries, very good cold tolerance
and some disease resistance. This species has been utilized in the former Soviet
Union as well as Eastern Europe in crosses with V. vinifera to produce
numerous hybrid series, widely known for their good cold tolerance and Plasmopara
resistance. These hybrids were produced in an attempt to extend the northern
range of viticulture, and have also been utilized for breeding in Minnesota,
Canada, Germany and Eastern Europe. Such cultivars do not offer the same wine
quality as V. vinifera, but they are much more cold hardy and could be
improved further.
Perhaps the most important attribute of Chinese grape germplasm is its potential
to have very strong resistance to fungal diseases. Grape species from the very
humid subtropical area should be challenged by many fungi and may possess strong
resistance. Few English studies have been published on the resistance of these
species, but they do provide a valuable germplasm resource. Access to Chinese
grape germplasm is limited and these species represent the most poorly collected
of all Vitis. The Chinese government is very hesitant to release grape
germplasm, and our importation laws preclude easy acquisition of these grapes.
However, there are increasing numbers of contacts with Chinese scientists and
controlled crosses and seed populations may provide the avenue for collection
of these grapes.
The lack of documentation, study and concern about grape germplasm is not limited
to the Middle East and Asia. The third center of origin of Vitis exists
in North America, and this region is also beset by relatively poor documentation
of its grape species, in terms of taxonomy, characterization and availability.
North American grape species are divided into two taxa; either as sub-genera
or as separate genera (Vitis and Muscadinia by some accounts).
Current GRIN-accepted taxonomy puts the 40 chromosome species formerly known
as Muscadinia rotundifolia (and others) into the genus Vitis.
This determination is unclear due to conflicting taxonomies. Species from these
two taxa are found throughout North America from southern Canada to northern
South America. There are about 20 species in North America, although that number
may be as high as 40 by some accounts. All the species within Vitis are interfertile
and they freely hybridize where they are sympatric and their bloom dates overlap.
Such opportunities make the occurrence of natural hybrids and hybrid zones common
and can lead to confusing taxonomic delineations. The exception to this rule
is that the 38 and 40 chromosome species are not interfertile, only rarely produce
viable progeny when crossed.
Almost all North American grape species grow near a permanent source of water
- either a stream, river or spring. All but one are vines and grow supported
on trees and fences to various heights. Most of these species are primary successors
and they tend to die out as forest canopies produce enough shade to limit their
growth. Some of the species are plentiful and are commonly found throughout
their range, while others are quite rare and survive in endangered habitats.
Vitis rupestris was once found in gravelly and sandy creek beds from
Tennessee to Texas. This species is shrubby in nature and has been grazed to
near extinction across much of its range since the opening of the south central
US to agriculture and cattle. It is only relatively common in southern Missouri.
Vitis rupestris has a deep penetrating root system to hold itself in
rapidly flowing, highly erosive streambeds. It also propagates very readily
from dormant cuttings and resists the root aphid phylloxera. It has been widely
used in rootstock development and is a likely parent in future rootstock breeding.
A recent survey of this species by Lamboy and Pavek (Am. J. Enol. Vitic. 49:356,
Hortscience 36:232-235) found it scattered, but rare across its range where
it occupies habitat that is threatened by grazing, development and flooding.
Other Vitis species that are threatened include V. acerifolia, V.
aestivalis, V. monticola, V. palmata, V. shuttleworthii and two natural
hybrids V. X champinii and V. X doaniana. Vitis
acerifolia grows in southern Kansas and Oklahoma into north Texas and New Mexico.
It is relatively uncommon and its habitat suggests that it should have strong
drought tolerance. It roots well from dormant cuttings and some accessions have
been shown to resist root-knot nematodes (Olmo, Walker).
Vitis aestivalis is found across the eastern US from Texas to Florida
and north to New England. Perhaps the most valuable form of this diverse species
is V. aestivalis var. glauca. This form of V. aestivalis
has good fruit quality, large berries and good resistance to foliar diseases
such as powdery and downy mildew, and Pierce's disease. Pierce's disease (PD)
is of particular importance. This bacterial disease rapidly kills V. vinifera
cultivars and has the potential to dramatically impact California vineyards
due to the introduction of a new more efficient vector, the glassy winged sharpshooter.
Vitis aestivalis var. glauca has been used to produce fruiting
hybrids (the Munson hybrids) as it lacks the strong fruit flavors of the grape
cultivars based on V. labrusca, while possessing valuable disease resistance.
Urbanization and agriculture also threaten this species.
Vitis monticola is found across the central and northern parts of the
Edwards Plateau in Texas, although it is not abundant. This weak-growing species
is usually found in extremely droughty areas on juniper or mesquite and without
an obvious source of permanent water. Although it roots poorly, it may be an
excellent choice for drought tolerant rootstock breeding because its progeny
might tolerate drought while possessing a smaller, less vigor promoting root
system. It should also be an outstanding source of lime tolerance since it is
often found growing on limestone deposits.
Vitis palmata is a relatively rare species that inhabits the south central
United States and is found in swampy conditions. Although virtually all grape
species are associated with permanent water, their root crowns are rarely found
in standing water. Vitis palmata is one of the few species that appears to tolerate
these low oxygen swampy conditions. Phytophthora root rot is a fungal disease
of grape most often found in overly wet soils. Resistance to this disease may
be more related to how well a given rootstock tolerates wet, low oxygen soils.
If so, V. palmata would be a useful parent in the breeding of such rootstocks.
This species is not common and its habitat is becoming more restricted with
the growth of agriculture, spread of cities, and draining of wetlands.
Vitis shuttleworthii is native to central and southern Florida, where
it is rapidly facing extinction from land development. This species is closely
related to V. mustangensis (V. candicans), which is found from
Texas across to the southeast. Vitis shuttleworthii has relatively large
berries and high levels of resistance to Pierce's disease and a host of damaging
foliar fungal diseases, as well as moderate resistance to dagger nematodes.
It has been used to produce fruiting hybrids for the southeastern US in the
past (Fennell), and remains valuable.
Two relatively rare Vitis species are natural hybrids with restricted
ranges due to human population expansion and limited opportunity to reform these
hybrids. Vitis X champinii is found in central Texas on the Edwards
Plateau where it formed through hybridization of V. mustangensis X
V. rupestris. Vitis rupestris is now very rare in Texas and the opportunity
for this natural hybrid to reform is restricted. True V. X champinii
is already rare and there are few populations to maintain the species. There
are other natural hybrids between V. candicans and V. monticola
and with V. cinerea var. helleri, (V. berlandieri), which
resemble V. X champinii, but they may not possess the excellent and broad
nematode resistance of V. X champinii. Vitis X doaniana
is a second natural hybrid with V. mustangensis as one of its parents and V.
acerifolia as the other. This species is found from northern Texas to southern
Oklahoma. It grows in very dry areas, should have good adaptation to drought
(with a deep root system), and may possess good nematode resistance. Both of
these natural hybrid species are in need of taxonomic revision and both have
value as rootstock parents.
Although grape species in the US are relatively well characterized, confusion
as to which are valid taxa remains. This confusion results from conflicting
taxonomic descriptions and from the tendency of these species to form hybrid
zones where they are sympatric. There have been several relatively recent efforts
to delineate and describe Vitis in the south and east (SIDA 19:123-131, SIDA
14:339-367; SIDA 12:279-286), but an overall work is badly needed. The grapes
from south of the US border to northern South America are very poorly characterized
and several new species have been described (SIDA 12:273-277). Some of these
species are native to tropical areas and should contain high levels of resistance
to Pierce's disease. Much of the resistance to PD comes from Vitis rotundifolia,
a species with peculiar fruit and horticultural characters, and genetically
incompatible with most Vitis species. Additional forms of PD resistance from
bunch grapes species native to the southeastern U.S. would greatly benefit breeders.
Grape breeders acquire germplasm to enable their breeding efforts. These collections
are held at the breeder's station and are relatively unavailable to others because
of poor centralized documentation and limited funds for distribution. The greatest
danger such collections face is retirement. In the past 40 years, grape breeding
programs have been eliminated at Southwest Missouri State University (Mountain
Grove), University of Missouri, Rutgers University, Virginia Polytechnic Institute,
North Carolina State University, University of Florida, Clemson University,
University of South Dakota, Oklahoma State University, and USDA programs in
Illinois, Mississippi, and Beltsville, Maryland. Much of the germplasm developed
in these collections has been lost. Ron Lane retired in 1997 from the University
of Georgia. He was a muscadine grape breeder and had acquired an excellent collection
of this unusual and highly disease and insect resistant grape. When he retired
his position was not replaced and this collection is now endangered due to uncertain
future funding. John Mortensen retired in 1993 from the University of Florida.
He spent most of his career developing bunch grape cultivars. As in the case
of Dr. Lane, his position was not replaced, and the collection of germplasm
he developed also faces an uncertain future. These collections contain resistance
from a variety of species to a wide range of fungal and bacterial diseases.
In addition, very strong resistance to phylloxera and nematodes is also present.
They contain germplasm that may be irreproducible and would greatly benefit
grape breeders in the US and around the world.
Other unique and valuable germplasm from private breeding programs is in danger
of being lost. Fennel developed some very disease resistant germplasm from V.
tiliifolia, 'Tamiami' being one example of a cultivar with high levels of
resistance to PD and fungal diseases, with large fruit clusters and good fruit
quality. Dunstan developed a number of Vitis x Muscadinia hybrids
that were backcrossed to interspecific Vitis hybrids. The offspring from these
difficult to accomplish crosses have many characteristics of both parents and
restored fertility (often lost in Vitis x Muscadinia hybrids).
The above collections primarily contain breeder selections from various hybrid
progeny. There are also collections of species germplasm that need to be preserved.
In addition to a large private germplasm repository of North American Vitis
species accessions, Barry Comeaux has amassed the world's largest collection
of North American Vitis herbarium sheets during his collection trips
over the past 20 years. His collections of species from across North America
have been sent to both Repositories and need to be encouraged with funding and
maintenance. His collection material is well documented with detailed collection
data and accurate taxonomic descriptions, something often missing from the USDA
Repository collections, which contain limited passport data.
The imperiled nature of grape germplasm collections is not limited to the
United States. The collection of wine grape cultivars at the Agriculture Canada
Research Station in Summerland, British Columbia, is also at risk due to changes
in research focus and the reprioritization of Agriculture Canada funding. The
collection at Summerland was unique in its focus on cold hardy V. vinifera
cultivars, and hybrid materials from Eastern Europe. Agriculture Canada also
withdrew support for maintenance of their vineyard at the Certification and
Importation Center in Saanichton, British Columbia. Many of these materials
are now located at a consortium of four private nurseries in eastern Canada.
They have been preserved, but a large collection of germplasm with limited direct
economic value may not be safe in private hands.
Germplasm Needs
There are a wide variety of research activities and funding efforts needed
to improve the grape germplasm status of the US. A primary goal of the NCGR
sites should be to fully document and characterize their collections. These
efforts should include complete, as far as possible, passport information, evaluation
of critical traits such as sex expression, fruit characteristics, vine morphology,
and molecular descriptors. This information should be documented in the Germplasm
Resource Information Network (GRIN). Much of this work is underway or complete,
and efforts are now shifting towards additional characterization through DNA
analysis (Genome 44:432-438).
There is a strong need for complete taxonomic description and revision within
grape. This includes not only the obvious areas where information is lacking
such as Asia and Central America, but also the United States. These efforts
should also focus on documenting diversity within and distribution of the various
grape species, preliminary analysis of their vulnerability to habitat loss,
and the development of plans to complete NCGR collections. Most importantly,
these studies should promote increased efforts to characterize the resistance
and horticultural traits of these species.
New collections of grape species are badly needed. These should focus on areas
where grape species are endangered and the many under-collected and under-documented
areas of the world such as Asia, Mexico, Central America and the Middle East.
Many of these species may be adequately represented in collections around the
world, but information regarding these collections is rarely accessible. Efforts
to document and catalog international collections are critical. To do this,
NCGR personnel should actively cooperate in international grape characterization
efforts.
One of the greatest limitations to collection efforts is the grape importation
quarantine. This restriction prevents ready collection of germplasm making it
difficult to respond to breeder needs or to acquire endangered collections and
species. This situation has improved with the institution of a Research Evaluation
Quarantine at the USDA Plant Genetic Resources Unit in Geneva, New York, but
other such systems should be encouraged in California and at public institutions
across the country. The Geneva facility has worked smoothly, while safeguarding
the industry from potential pathogens from overseas. Quarantined vines are now
fruiting and available to breeders for evaluation and use in hybridization.
Vulnerability of Germplasm Collections and Access to Herbaria Specimens
Grape breeders are the primary holders of grape germplasm. They not only amass
genotypes of immediate interest to the specific goals of their breeding program,
they also acquire almost anything. Much of this acquired germplasm has no immediate
or even future use in these programs, but it might be very valuable in other
programs. However, these collections are poorly documented and catalogued. A
database detailing what is available and where it exists would be very valuable
to both NCGR programs in terms of acquisition and assistance with distribution.
Collections also exist at many public universities and colleges such as those
mentioned above in relation to breeder retirements and at such places as Grayson
County College in Denison, Texas where many of T.V. Munson's hybrids are assembled.
Databases of these collections should become subsets of the NCGR collections
to facilitate the use of this germplasm. Germplasm in these collections also
needs to tested and treated for the important grape viruses so that restrictions
to movement and utility are eliminated.
Preservation of germplasm collections is also critical. The germplasm of retired
breeders is frequently at risk and once such collections are cataloged, they
should be examined to preserve what may be of value in the future. Funding the
acquisition of valuable material and its establishment at NCGR sites is very
important. Availability of space and funding for maintenance are always important
issues surrounding germplasm maintenance. Efforts towards cryopreservation and
storage of in vitro plants need to be intensified, with documentation that these
forms of germplasm maintenance will serve the user community. Funding should
also be made available to preserve grape habitat for in situ germplasm maintenance,
although given the role of grape species as a primary successor species these
habitats will have to be managed. Typical grape habitat could also be maintained
and stocked with germplasm, as an alternative to preserving in situ collections.
Both forms of conservation might help alleviate the concerns of space availability
and maintenance costs at the NCGR sites.
There is also need for research on the preservation of genetic reserves through
seed and or pollen collections. Grape seed and pollen lose their viability in
relatively short periods of time. If viability could be extended and collections
and distribution of these grape germplasm sources facilitated it would be very
beneficial. It is relatively easy to amass collections of grape seed and pollen,
and in so doing preserve a region's genetic diversity. Importation restrictions
on these materials are relatively uncomplicated making acquisition of genetic
diversity from international sources possible and convenient.
Finally, grape herbaria resources need to be catalogued. These herbarium sheets
record the existence of grape species and hybrids over time. Changes can be
observed and genetic change measured through DNA analysis. However, the existence
of these resources is poorly documented and a centralized organizational structure
is needed. The NCGR sites could catalog collections and provide information
on their location, species composition and availability, and make these databases
available on GRIN. These nationwide and hopefully international resources would
greatly benefit the knowledge of Vitaceae and help direct where resources for
germplasm acquisition should be spent.
Respectfully submitted by the Grapevine Crop Germplasm Committee
Membership, 2000/2001:
Bruce Reisch, Chair, Cornell University
Andrew Walker*, Vice Chair, University of California, Davis
Kendra Baumgartner, USDA-ARS Crops Pathology and Genetics Unit, Davis
David Cain, International Fruit Genetics, California
Carmo Candolfi, Oregon State University
Peter Cousins, USDA-ARS-PGRU, Geneva
Gregory English-Loeb, Cornell University
Phil Freese, Winegrow, Inc., California
Richard Gahagan, Bureau of Alcohol, Tobacco and Firearms, U.S. Dept. of the
Treasury
Charles Hossom, AgriVitis, California
Nancy Irelan, E&J Gallo Winery, Modesto
Jiang Lu, Florida A&M University
James Luby, University of Minnesota
Carole Meredith, University of California, Davis
Robert Pool, Cornell University
Andrew Reynolds, Brock University, Ontario
Robert Wample, California State University, Fresno
Wayne Wilcox, Cornell University
* Primary author of vulnerability statement
Ex-Officio:
Warren Lamboy, USDA-ARS-PGRU, Geneva
Charles Simon, USDA-ARS-NCGR, Davis
Bernard Prins, USDA-ARS-NCGR, Davis
J. Scott Cameron, USDA-ARS, National Program Leader, Hort/Sugar
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