Miglioramento genetico e biotecnologie del seme
The course aims to give the basic principles of plant breeding, of cultivar selection and of seed production. To this aim, theoretical and practical aspects of reproductive biology of higher plants are addressed including those modifications of the reproductive system that are of practical interest. Additional teaching objectives are the collection, storage and evaluation of genetic resources, the development of plant breeding schemes, the characterization, reproduction, conservative selection of plant varieties, the adoption of advanced strategies for the control of reproductive biology and the co-existence of conventional and genetically modified crops.
- Introduction, history and aim of plant breeding, concept of ideotype. - Biology of plant reproduction: floral morphology, macro and microsporogenesis, macro and microgametogenesis, pollination, progamic phase, fertilization, embryogenesis, seed and fruit development. Molecular biology of flowering induction and flower development, genes controlling inflorescence, flower and floral organs identity, ABC(DE) model. Mode of reproduction (sexual reproduction, vegetative propagation, apomixis), sex determination (hermaphroditism, monoecism, dioecism), mating system (autogamy and allogamy), experimental characterization of plant reproductive system and of outcrossing rate. Male sterility (genetic, cytoplasmic and genetic-cytoplasmic, functional and conditional). Self-incompatibility (sporophytic and gametophytic). Apomixis, cytoembryological bases, genetic control, breeding of obligate and facultative apomictic species, perspectives of transferring apomixis to sexual species. Fruit set and development, parthenocarpy, biotechnological approaches to control fruit set. Fruit ripening, mutants affected in ripening and in pigment accumulation. - Sources of genetic variability: gene pool concept, germplasm collection and storage, seed banks, germplasm evaluation, variability induced by mutagenesis, somaclonal variation. - Intra and interspecific cross, sexual interspecific barriers, biotechnologies to facilitate interspecific crossing, in vitro fertilization and embryo rescue. - Theory of selection: principles of theory of selection for monogenic and polygenic characters, penetrance and expressivity. - Genetic population structure in autogamous, allogamous, vegetatively propagated and apomictic species. - Breeding schemes for autogamous species: selection in existing populations: mass selection and pure line selection. Selection in segregating populations: pedigree, bulk and single seed descent methods, double haploids. Backcross method to transfer a dominant and a recessive allele, linkage drag, principles of marker assisted selection, multiline varieties, F1 hybrids in autogamous species. - Breeding schemes for allogamous species: mass selection, recurrent selection, synthetic varieties, F1 hybrids in allogamous species, use of male sterility in hybrid production schemes. - Principles of genetics of seed production: evaluation of new varieties, subscription to the Register of Varieties, maintenance selection and seed production, isolation, generations of seed multiplication. Legislation related to seed production and marketing. Biotechnologies for the protection of plant varieties (molecular markers for distinctiveness), estimation of genic flux and gene flux containment in conventional and genetically modified varieties.
Seminars: students will be invited to attend one or two seminars focussing on technical and/or scientific aspects related to topics of the course. Practical activities: practical activity will be dedicated to the knowledge of genetic variability in a crop species, to the examination of mutants involved in reproductive biology, to technicalities to carry out controlled crosses and to a visit to a company or experimental station involved in breeding and/or seed production of crop species.
- Barcaccia G. e Falcinelli M., Genetica e genomica, vol. II, 2005, Miglioramento genetico, Liguori. - Lorenzetti F. et al., Miglioramento genetico delle piante agrarie, 2018, Edagricole. - Materiale fornito dal docente tramite il Portale Docente.
Dates of beginning and end of teaching activities
Objectives of the course
Università degli Studi della Tuscia - Rettorato, Via S.M. in Gradi n.4, 01100 Viterbo, ITALY - Tel. 0761.3571