StatusThe thesis was presented on the 28 April, 2011
Approved by NCAA on the 8 July, 2011
Abstract– 0.53 Mb / in romanian
The structure of the thesis: introduction, 6 chapters, general conclusions and recommendations, bibliography of 340 sources, 5 annexes, 164 pages of base text, 48 figures, 44 tables, 20 photographs.
The obtained results are published in 70 scientific works.
The domain of studying: the population biology.
The purpose: the establishing of the population and morfo-fiziologic peculiarities of the oak species having in view the maintenance of the genetic diversity in the forest stands; the determination of the termotolerance and the adaptation at high temperatures for the appreciation of the spreading specific charter of the principal species of oak from the Republic of Moldova.
The objectives: the revealing of the tendencies in the display of the variability in the natural populations at the pedunculata oak and the fluffy oak; the establishment of the growth dynamics of the pedunculata oak posterity depending on the genitors specificity of the sowing period; the estimation of the heredity, the characters of the growing energy and the quality features of the trunk at the pedunculata oak posterities; making evident the laws of the terms inheritance of the covering with foliage the oak sapling in polymorphic and consanguine population; the establishment of stability to heats of various kinds at different species of oak on the basis of methods of electrolytes leakage and fluorescence; the establishment of the leaves thermotolerance at genotypes of a pedunculata and a fluffy oak with the help of electrolytes leakage; the characterization of the adaptive potential to the influence of heats over the oak species with the help of the fractiotion method of doses.
The scientific novelty and originality. Laws referring to the display of the phonotypical variability of leaves, generative bodies, trunk and crone at trees in populations of oak species were revealed. It was proved that the signs and properties of the individuals are characterized by a certain level inside the population variability and that the morphological, phenological and physiological properties of the parent trees are descended to the posterity. The methodology of planning the experiments which allow to reveal the quantitative distinctions between the thermotolerance of species and genotypes on the basis of the specificity electrolytes leakage from the leaves segments which were exposed to various doses of thermal shock. On the basis of the given method the thermotolerance and the adaptive potential at high temperatures of oak species from the Republic of Moldova were established.
The theoretical significance. It was proved that the intraspecific structure of the pedunculata oak consists of subordinate mendelian populations which differ in morphogenesis and the adaptive capacity of the leaves. Because of this fact, at the application of regeneration works of the oak forests it was motivated that the necessity of a choice of specific genotypes of oak that will allow keeping the heterozygosity of the acorns for the preservation of the complex of signs characteristic proper to the local population. New methods were applied to determine the thermotolerance at the oak species: 1) the method based on the properties of the cellular membranes of the leaves to maintain the electrolytes, with the help of the conductivmetres; 2) the fractionation method of the thermal shock doze; 3) the determination method of the thermotolerance on the base of the photosistem II activity with the help of the fluorimetry.
The applicative method of the work. We consider that the territory occupied by a group of populations must make a separate zone of gathering and utilization of the acorn. The transfer of the seed material (seeds, seedling) in the boundary of a group of population provides the forest plantation of oak the capacity of adaptation, productivity and resistance in relation to the influence of adverse natural factors. Of great practical value are the results of research which had revealed the growth features of the pedunculata oak posterities depending on the nature of genotypes and the period of sowing. It is recommended in action of afforestation the gathering of acorns to be made from a big number of phenotipical oak trees from natural populations while the sowing to be realized early in spring with stratified seeds.
The implementation of scientific results. On the basis of studying the population variability of the pedunculate oak were elaborated “Recommendations about the creation of seminological bases in the state fund from the Republic of Moldova”, published and distributed to the Silvic Entreprises for execution. The received results are used in the course of students training from the speciality “forestry and parks” of the “Botany, Ecology and Forestry Chair” from MSU. Some results are included in the methodical guide-book dedicated to students for the elaboration of course thesis at the discipline “Forest nurseries”. At practice carried out on “wood cultures” in the reservation “Plaiul Fagului” the students study the cultures of maternal descent of the pedunculata oak.