INTRODUCING PUNICOLOGY IN THE XXI CENTURY

1. Liquidation or dissociation of actively working punicologists; 2. Creation of an International Punicological Center; 3. Creation of international periodic punicological editions; 4. The periodic organization of international conferences and seminars of which the purpose should be to exchange results of pomegranate research, of new grades, training for new techniques, etc.

A special problem lies in revealing the preserved centers of concentrations of wild pomegranates within the limits of their natural area as a source of variability in the future, defining the necessity of their protection, studying the characteristics and properties of pomegranate plants within the structure of these populations and drawing up a list of them. Special interest goes to the populations along the borders of an area, and behind those borders it is necessary to achieve their legislative inclusion within the structure of protected territories.

Among the potential core problems of studying pomegranates are the following: 1. creation of a uniform databank; 2. creation of a world collection of a genofund of various pomegranate grades and forms; 3. creating, on the basis of a world collection of a core-collection of pomegranate grades and forms, its duplication in different regions and ecological conditions in the basic regions of pomegranate culture and regional centers of its research and selection; 4. creation of a uniform technique of studying collections of pomegranate grades and forms; 5. studying this core-collection of pomegranate grades and forms by a uniform technique in various regions and ecological conditions that will allow the influence of geographical and ecological factors on variability of the basic attributes and properties of various pomegranate grades to be revealed; 6. studying distinctions of width of norm of reactions in various ecological and geographical groups of pomegranate grades and forms, from a uniform background and in various conditions; 7. regional division into territorial districts, revealing the optimum culture of pomegranates of different areas and their specialization and concentration in industrial plantings; 8. revealing the limited number of the best industrial pomegranate grades for various purposes and terms of maturation for each region and area of industrial culture; 9. revealing existing mutations and creating new mutations of pomegranates, and drawing up a list of these; 10. revealing, on the basis of studying a world collection of pomegranate grades and forms, sources and donors of attributes and properties valuable to selection, and characteristics of their inheritance during crossing; 11. creation of zonal and regional models of pomegranate grades; 12. development and use of genetic engineering methods to accelerate the pomegranate selection in a number of directions, including: an increase of stability with regards to abiotic factors (winter frosts, spring frosts, salt-tolerance) and biotic factors (wreckers, illnesses); the reception of grades with a prolonged period of winter rest; an increase of a degree of soft-seededness or seedlesness and its stability at grades of various terms of maturing; deducing of pomegranate grades, giving juice while keeping a complex of biologically active substances stable.

Among selection problems the basic directions of deducing new grades are represented: seedlessness, various maturation terms, taste, duration of keeping the fruit; with a high % of output and quality of juice and keeping this stable; with a consistently limited number of trunks; forming a limited number of radical shoots; with raised keeping of fruits; absence of layers between piths inside of the fruit, with easily separable grains (juicy seeds).

The development of methods is represented as follows: a) the accelerated allocation of sources and donors of attributes and properties valuable to selection; b) an acceleration of terms of introduction into fructification selection of seedlings as a reduction of the virginal period; c) the accelerated breeding and propagation of new grades.

A continuation of research is necessary, such as: a) Technological: 1. an expansion of a spectrum of foodstuff from pomegranate fruit processing and methods for long storage of pomegranates without loss of quality; 2. products from recycling all the waste of pomegranate fruit processing; b) Pharmacological, the use of products obtained from processing various pomegranate bodies in pharmaceutical and medical practice.

Domestication of pomegranate, one of the most ancient fruit crops, and the beginning of its spontaneous selection are separated from our time by not less than 50 centuries. During this time from initial selection numerous and various grades in various regions have all been allocated.

From the start of its culture and selection centuries ago a cultural evolution of pomegranates has led to changes in many directions: 1. the sizes: a) increase (fruit, grains) and b) minimization (the sizes of plants, fruits, thickness of pericarp, hardness and sizes of seeds); 2. stability: a) abiotic factors (frost resistance, drought resistance, salt-tolerance, solar burn of fruits, cracking of fruits) and b) biotic factors (wreckers, illnesses); 3. increase of efficiency; 4. improvement of fruit quality; 5. increase in the duration of keeping the fruit.

It is possible to unite the modern achievements of pomegranate selection into groups, considered as a microevolutionary shift: 1. new changes of habitus, the size and the form (determinant forms, dwarfs, decumbent forms); 2. soft-seeded grades: a) acid-sweet taste and b) super-early term of maturation; 3. rather cold-resistant grades; 4. decorative forms (doubling flowers, colour of flowers and fruits, the sizes of plants and fruits).

The necessity of the reception of new grades is obvious. Scientific selection of pomegranates is a young science. Its modern level, despite the certain achievements, does not yet meet the needs of fruit production and potentialities of a science. Modern selection comes from a principle of development of grade models. They are theoretically achievable ideal types of plants of which genetic opportunities answer problems of selection. Models of grades are caused historically and by permanent change in time, depending on the problems put by time. The question of the creation of models of pomegranate grades had been posed by us in 1979 (Levin, 1979). Various models of pomegranate grades differ in a few attributes: frost resistance, the sizes of crowns, durability of branches and keeping of fruits. We allocate a number of stages of pomegranate selection (which can be disconnected in time and space): 1. Gathering and studying initial material for selection: a) expedition inspection of genetic resources of pomegranates in their centers of diversity (coenopopulations of wild-growing pomegranates, the age-old centers of culture, the centers of modern culture, the selection centers); b) the introduction of a genofund; c) the organization of a genofund collection (as introduction populations); d) studying the samples of a genofund collection; e) the creation of a core-collection; f) the allocation, from a genofund collection, of sources and donors of attributes and properties valuable to selection; 2. Development of grade models in directions of use and regions of culture; 3. Change of genome (formation of new mutants or recombinant genotypes) and creation of selection populations (including formation from free pollination); 4. The accelerated use of the sources of genetic variability (receptions, grafting, use of pollen after cryoconservation, etc.); 5. The accelerated cultivation of hybrid material; 6. Early diagnostics at roguing (a combination of natural and artificial selections); 7. The transplantation of selected hybrid seedlings (segregants) in a hothouse or in a garden in a constant place; 8. The accelerated ontogenesis and selection at the level of individuals or embryoids (in use of somaclonal variability) in a laboratory, a hothouse, and in a garden: a) modelling phenotypes (average individuals), as the most adapted; b) “nonconventional” genotypes; c) transgressive individuals; 9. The accelerated and microclonal duplication of new grades in a laboratory, a hothouse, a nursery; 10. Ecological tests (screening) for study of new grades in an environment; levels: a) a collection of a genofund; b) collection tests in various scientific research establishments in different ecological conditions and geographical zones; c) tests by a technique of state strain testing by transplantation of elite seedlings to a constant place (the accelerated station test); d) state strain testing; e) industrial test; f) pioneer culture on the northern border of a cultural area and behind its limits.

To work on pomegranate selection it is necessary to concentrate in the region having a natural provocative background for selection to many attributes and properties. Selection from regions that are close to the centers of origin and from a diversity of plants is most successful. These regions often differ in the increased natural radiobackground that promotes increased natural mutagenesis. It has rather evidently come to light in the comparison of results of selection work on the Turkmen experimental station of VIR and in Azerbaijan and Tajikistan.

The breeder should have the extensive and studied genofund "near at hand", to have an opportunity to choose the necessary initial material for selection in the chosen direction according to the developed grade model, including sources and donors of the major economic-biological attributes and properties, to test hybrid seedlings on different environments.

It is more economical to do similar work in a region of natural growth of wild pomegranates along the northern border of its area, in an area of uncovered cultures or in a region with similar climatic conditions. In similar conditions where intensity of selection increases, its productivity increases. One of such potential regions for pomegranate selection has appeared in Southwest Kopet Dagh (Turkmenistan), where on the former Turkmen Experimental Station of VIR in Garrygala (former Kara-Kala) there were all the above-listed favorable conditions. This station, as a basis for the introduction of pomegranates, possessed the world's largest introductory population of pomegranates and a provocative background for its selection in stability to abiotic and biotic factors, and had all the preconditions to transform into the largest selection center of pomegranates.

Among the methods used in selection work with pomegranates, it is possible to allocate 4 blocks:

1. Sowing of seeds from free pollination; 2. Intervarietal hybridization and its variants (heterosis selection, transgressive selection, introgressive selection); 3. Mutagenesis: use of chemosupermutagens, radiating selection, selection of somatic mutants from clonal selection; 4. Bioengineering, set genoengineering and biotechnological methods.

The intensification of the selection process requires the specialization and association of efforts of scientists of different structures (breeders, variety investigators, cytologists, phytopathologists, entomologists, biochemists, physiologists, agricultural technicians, technologists, etc.) for the decisions about the problems connected with the creation, propagation and introduction in production of new pomegranate grades. The experimental hybrid populations are created in the first stage, they differ by a regime of selection. The selection process intensifies rigid rejection of seedlings at early stages of development on provocative backgrounds both overlapping in time and space of stages of primary study and state strain testing.

The intensification of selection reduces its duration and the period of rotation of seedlings and their sizes. There is an opportunity to increase the number of hybrid seedlings per unit of the area. Duration of the period from hybridization before division into production of a grade takes 24-30 years. The use of various receptions of acceleration allows the considerable reduction of the whole process, or to facilitate reception and use of the initial material necessary in concrete cases.

The grafting of a cutting for bark of new grades-introducents on a strong perennial stock allows their use for crossing in a year of reception. In 1994 such grafting had been done by us on 5 May, flowering on scion at horizontal orientation of shoots had begun in 115 days on 30 August. Fruits had been removed in 70 days on 8 November (at the presence of green leaves on scion). Experiences in 1985-1986 have shown that germinating seeds as a result of hybridization are formed at duration of growth of fruits not less than 60-75 days (germination of seeds reaches 0,32-10,63%). The pollen of a pomegranate prepared in April-June loses viability quickly enough. Late terms of crossing are possible: 1. Storing of pollen in an exicator with chloride calcium in a refrigerator; 2. Preparation of pollen in July-August at late flowering, especially on non-fructified plants; 3. Use of the pollen stored in a regime of cryoconservation at a temperature of -196ºС.

To test the suitability of a pomegranate for some methods promoting acceleration of the selection process is necessary. These methods are: 1. Reception of seeds by entering pollen directly into the ovary, bypassing the stigma (“interovarious” pollination); 2. Cultivation of ovules in vitro, especially in selection of earliness; 3. Increase of hybrid seed germination from unripe fruits at late terms of hybridization (by storage of such fruits at the lowered positive temperatures, for example, in a refrigerator); 4. Allowing germination of unripe seeds (in our experiences to allow the germination of pomegranate seeds collected in August) and the further cultivation of seedlings in closed ground during the cold period in conditions of photoculture; 5. Culture of hybrid seedlings by hydroponics (in accordance with the experience of hydroponic pomegranate cultures of E.A.Gabrieljan-Beketovsky in the Institute of Gardening and Wine Growing in Yerevan in Armenia) and aeroponics.

Growth and development of hybrid seedlings can considerably accelerate the sowing of seeds and cultivation of seedlings in containers in a hothouse in photoculture (a similar experiment under our request, with use of our seeds, has been put in the Institute of Biophysics of the Siberian Branch of the Russian Academy of Science in Krasnoyarsk).

The term of allocation of elite seedlings before state strain testing of grades is considerably reduced in plants transplanted to a garden in a constant place and their study by accepted techniques in state strain testing. The following can serve as material and a place for selection of segregants of pomegranates:1. Local coenopopulations; 2. The centers of age-old culture of local grades; 3. Collections of a genofund of various regional scientific institutes; 4-5. Hybridogen and mutagen populations of these establishments; 6. Populations of seedlings from free pollination; 7. Populations of cryptoclones; 8. Populations of somaclones, allocated in culture in vitro.

The great value should be in the creation of essentially new initial material: radiomutants and chemomutants, polyploids, etc. The basic material for plant breeders is represented by sources and donors of attributes and properties valuable to selection. The author was allocated as sources 20 attributes and properties valuable to selection 271 grades and forms (24,3% from an aggregate number of samples of a collection), as donors to 5 attributes - 7 grades and forms in a collection of a pomegranate genofund of the Turkmen Experimental Station of Genetic Resources of Plants (former Turkmen experimental station of VIR).

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