|Analytical review of the current status and maintenance of fruit and berry germplasm accessions at Pavlovsk Experiment Station of the Vavilov Institute of Plant Industry (VIR)
Developed by Vavilov Institute of Plant Industry (VIR)
The lands whereon Pavlovsk Experiment Station is now situated were previously used by the local population for cultivation of fruit and berry plants and are one of the oldest centers of boreal horticulture. Soil and climate conditions in this area are exceptionally favorable for growing a wide diversity of different crops, including demanding ones, such as cherry, sour cherry, pear, etc. It was not by chance that Acad. N.I. Vavilov chose this very site for preservation of fruit and berry germplasm diversity.
Formation of the collection of fruit-bearing plants, largest in Northern Europe, was started under Vavilov’s leadership in 1926. The ex situ plant genetic repository was built up on the basis of local landraces from European Russia, Siberia and the Far East as well as the accessions collected in the late 19th/early 20th centuries by E. Regel (1815 – 1892) and J. Kesselring, plant scientists and botanists. By the beginning of the 1940s, the collection comprised 2027 accessions, including 1759 accessions of berries, 148 of apple-tree, 45 of pear, and 75 of plum and cherry. Between 1937 and 1941 the scientists working at the station bred 16 cultivars of fruit and berry plants and selected 33 more as the best for practical utilization.
In spite of the severe winters in the beginning of the 1940s, when all the orchards in the North-West of Russia perished, and temporary occupation of Pavlovsk by the German Nazi forces in 1941 – 1944, more than 70% of the collection was saved. It became possible because of a correct collection management strategy and unique soil and climate environments at this site. These accessions, maintained at the station up to now, deserve to be called a “gold reserve” on a global level, as they have a potential to solve the problems arising in the present-day situation of changing climate.
After World War II, the efforts went on to accumulate at Pavlovsk Station genetic resources of:
− apple-tree from 35 countries of the world (USA, Canada, Great Britain, France, China, Scandinavian countries, Baltic republics, CIS countries);
− strawberry from 40 countries (all continents);
− black currant from 30 countries (North America, Western and Eastern Europe. Far East, West and East Siberia);
− honeysuckle (Kamchatka, Primorsky Region, Khakassia, Altai and other areas in Russia; Canada);
− plum and cherry plum 12 countries (Western and Eastern Europe, Altai, North America, Baltic republics and CIS, central regions of Russia).
At present, the collection maintained at Pavlovsk Experiment Station, consists of over 5,700 accessions of various fruit, berry and ornamental plants, including 634 accessions of apple (gen. Malus); 75 of pear (Pyrus); 19 of serviceberry (Amelanchier); 39 of rowan (Sorbus); 320 of plum, cherry plum, sloe (Prunus); sweet and sour cherry, microcerasus, bird cherry (Prunus); 232 of red currant and 893 of black currant (Ribes); 240 of gooseberry (Grossularia); 145 of raspberry and dewberry (Rubus); 273 of honeysuckle (Lonicera), actinidia, magnolia vine, viburnum; 986 of strawberry (Fragaria); and 1587 of ornamental plants. This is the largest field genebank in Europe and, among those situated on northern latitudes, in the whole world.
Among the collection accessions there are wild species, old landraces, and most widespread and promising cultivars of domestic and foreign breeding. Part of them have been irretrievably lost to the world, so Pavlovsk Experiment Station is the only place where they may be found.
The genetic diversity preserved at the station is an unmatched source of donors and useful genes for domestic and worldwide breeding practice. Continuous in-depth studies of the germplasm accessions make the collection even more unique: each of them obtains detailed characteristics of major economic and biological traits. This process results in publishing catalogues. For example, in the past 10 years 4710 accessions were studied. Among these, 1464 accessions underwent complex research (assessment of fruit’s nutritional value, resistance to abiotic and biotic environmental factors, etc.). As a result, 591 sources of the most important breeding characters (winter hardiness, disease and pest resistance, high palatable quality, increased content of bioactive substances) have been identified, and 1314 accessions have been passed over to domestic and foreign breeders and other users. In the State Variety Register of the Russian Federation there are 42 cultivars developed at Pavlovsk Experiment Station (7 crops: plum, cherry plum, honeysuckle, viburnum, gooseberry and strawberry). The most impressive example of efficient germplasm utilization is the release of the strawberry cultivar Festivalnaya – it has been cultivated in 11 out of 12 existing regions of Russia and was grown over the whole territory of the former Soviet Union (from Murmansk in the north to Transcaucasus in the south, and from Kaliningrad in the west to the lake Baikal in the east). It became the main cultivar for large-scale production and retained this status for several decades. Even now, despite intensive breeding efforts, this variety remains listed in the State Variety Register. Besides, a vast majority of present-day strawberry cultivars have been bred on its basis. If we take black currant only, over 60% of domestic cultivars have been bred at Pavlovsk Experiment Station. Similar amount of source materials was identified by the station’s staff for apple, sour and sweet cherry, honeysuckle and other crops.
It will be an irretrievable loss if part of the lands possessed by Pavlovsk Experiment Station of VIR (approximately 10 hectares) is conveyed to the Federal Fund of Residential Real Estate Development. This territory is currently occupied by all in vivo collections of berry crops (232 accessions of red currant; 893 of black currant; 240 of gooseberry; 145 of raspberry and dewberry; 986 of strawberry; 273 of honeysuckle, actinidia, magnolia vine and viburnum), stone fruit plants (320 accessions of plum, cherry plum and sloe; 302 of sweet and sour cherry, microcerasus and bird cherry), rowan (39 accessions) and ornamental plants (920 accessions), which amounts to 75% of all the accessions maintained in the field genebank of Pavlovsk Experiment Station.
Within the estate belonging to Pavlovsk Station, the acreage of horticulture-friendly areas is extremely limited. Moreover, such areas are already occupied by apple and pear collection orchards. All other lands are unsuitable for horticulture.
If the resolution passed by the Russian Ministry of Economic Development becomes a reality, all unique collections of fruit crops will be irrevocably lost. A transfer of the collection plantings with the use of modern technologies and international experience that may warrant total safety of the collections will take no less than 15 years and require additional investments amounting to several dozens of millions of U.S. dollars. Safe relocation of the fruit germplasm collections could be carried out only under the following conditions:
The collections may be safely relocated only to a prearranged site with horticulture-friendly land with the having acreage of 70 hectares.
Preparation of such site for relocation should include: phytopathological examination of the soil in order to trace soil pathogens; preliminary land reclamation, including irrigation; application of organic and mineral fertilizers at a plentiful dosage rate; establishment of shelter belts for the orchards; construction of access roadways and interconnecting roads; setting up temporary waterways for irrigation; building of fences; procurement of security guarding services; development of logistic infrastructure, including sheltered ground, laboratory facilities, management buildings, machinery and tractor stock, etc.
Uprooting of the old collection plantings can be accomplished only after fruit tests are performed in order to guarantee that a newly planted accession is identical to the initial one in the old collection. This process will require considerable time – from 2 to 12 years, as the period from planting to fruiting varies in different crops.
A regeneration nursery for fruit and berry plants needs to be laid out (3 hectares).
From 3 to 5 years will be needed for germplasm regeneration (depending on the crop). Some of the accessions require preliminary sanitation by tissue culture methods, which will considerably raise the costs of regeneration.
If the directives of the government are to be followed, the lands should be vacated in the first half of 2010, while the Vavilov Institute is expected to bear the burden of relocation alone. Such relocation measures as described earlier are extremely costly and will require a lot of equipment and qualified manpower. At present, neither VIR nor Pavlovsk Station is able to endure such expenditures.
The unique genetic diversity preserved at Pavlovsk Station cannot be maintained anywhere within VIR’s experimental network. Because of its northern location the station specializes in maintaining, first of all, winter-hardy accessions and those adapted to the specific regional environments. According to the estimates, from 70% to 90% of the accessions (depending on the crop) currently preserved in Pavlovsk may not be maintained anywhere else. Possibilities of duplicating the collections by tissue culture or cryoconservation techniques are now very limited. At present, VIR’s Biotechnology Department is able to maintain in vitro no more than 40 accessions of such crops as cherry, currant, strawberry, raspberry, honeysuckle or rowan. Their capacities at this moment allow them to preserve 150 accessions. As for cryogenic storage, currently it is possible to place honeysuckle, black currant or gooseberry germplasm into liquid nitrogen at a rate of 150 – 180 accessions per year, provided that such placement may be performed only while the plants are in dormant state, i.e. from October through February.
Any duplication techniques cannot exclude the risk of losses in the germplasm preserved. Therefore, maintenance of the accessions in the field genebank is mandatory for safe conservation of fruit plant genetic diversity.
The plant germplasm maintained at Pavlovsk Experiment Station of VIR is a “gold reserve” on a global scale, because it contains effective donors and genetic sources needed for the development of modern intensive-type cultivars able to solve the tasks of food and bioresource security in the present-day situation of changing climate.
The lands under fruit collection plantings at Pavlovsk Experiment Station of VIR are a unique focus of boreal horticulture due to the exceptionally favorable combination of soil and climate conditions beneficial for cultivating a vast diversity of fruit, berry and ornamental crops.
Pavlovsk Station preserves in vivo a unique genetic diversity of fruit and berry plants, the largest in Northern Europe, including wild species, landraces, most widespread and promising cultivars of domestic and foreign breeding, many of which are not maintained anywhere else except Pavlovsk.
Relocation of the collections is impossible because of the tremendous risk of losing the accessions, much greater part of which being unduplicated. Besides, such relocation will require considerable financial resources (several dozens of millions in U.S. dollars), while in the region there are no horticulture-friendly lands suitable for a field genebank.