logging in or signing up Plant Genetic Resources plantbreeding Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1653 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: July 13, 2010 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... By: KVN01 (8 month(s) ago) good presentation; touches on all important aspects Saving..... Post Reply Close Saving..... Edit Comment Close By: sekhar_gpb (16 month(s) ago) very nice presentation Saving..... Post Reply Close Saving..... Edit Comment Close By: sekhar_gpb (18 month(s) ago) very nice Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: Prepared for II BSc(Agri). COS,Chintamani Lecture-3 and 4 Domestication & germplasm conservation Slide 2: Prepared for II BSc(Agri). COS,Chintamani Key points for this lecture Domestication Selection under Domestication: 1. Natural i) Environmental selection ii) Environmental selection 2. Artificial Population Types of Selection: (1) directional selection, (2) stabilizing selection and (3) disruptive selection. Germplasm: (1) land races, (2) obsolete varieties, (3) varieties in cultivation, (4) breeding lines, and (5) wild forms and wild relatives. Gene pool concept: (1) primary (GP,), (2) secondary (GP2) and (3) tertiary (GP)) gene pools. Genetic erosion; features Germplasm activities Gene banks Gene sanctuaries Slide 3: Prepared for II BSc(Agri). COS,Chintamani Domestication is the process of bringing wild species under human management Gopher plant (Hevea sp.) Milkweed (Euphorbia lathyrus), Kala jeera (Bunium persicum), Slide 4: Prepared for II BSc(Agri). COS,Chintamani Selection under Domestication When different genotypes present in a population reproduce at different rates, it is called selection. A population may be simply defined as the group of individuals, which mate or can mate freely with each other. Selection is grouped into two types, on the basis of the agency responsible for it. natural and (2) artificial Slide 5: Prepared for II BSc(Agri). COS,Chintamani Natural Selection. The selection that occurs due to natural forces like climate, soil, biological factors (e.g., diseases, insect pests, etc.) and other factors of the environment is called natural selection. In 1962, Nichlson proposed that natural selection may be seen to operate through two mechanisms, viz.; (l) environmental selection and (2) competition. Environmental selection acts against all such genotypes that are unable to cope with the environmental stresses. Slide 6: Prepared for II BSc(Agri). COS,Chintamani Natural selection through competition occurs in crop populations where a plant takes up more water, nutrients or light than another at the expense of the other. Artificial Selection. is carried out by man and is confined to domesticated species. It allows only the selected plants to reproduce, ordinarily .makes plants more useful to man and generally leads to a marked decline in genetic variability in the selected progenies/populations. Types of Selection directional selection, stabilizing selection and (3) disruptive selection. Slide 7: Prepared for II BSc(Agri). COS,Chintamani Directional Selection. When individuals having the extreme phenotype for a trait or a group of traits are selected for, it is called directional selection. Stabilizing Selection. When selection favours the intermediate phenotype and acts against the extreme phenotypes, it is termed as stabilizing selection Disruptive Selection. In each 'ecological niche' a different 'phenotypic optima' is selected for so that the population ultimately consists of two or more recognizable forms; such a selection is called disruptive selection.. Slide 8: Prepared for II BSc(Agri). COS,Chintamani GERMPLASM The germplasm of a crop may be defined as the sum total of hereditary material, i.e., all the alleles of various genes, present in a crop species and its wild relatives. Germplasm consists of the following five types of materials: land races, (2) obsolete varieties, (3) varieties in cultivation, (4) breeding lines, and (5) wild forms and wild relatives. Slide 9: The sum total of genes in crop species important features of PGR Represents the entire genetic variability or diversity available in a crop species. Consists of land races, modern cultivars, obsolete cultivars, breeding stocks, wild forms and wild species of cultivated crops. Includes both cultivated and wild species and relatives of crop plants. Prepared for II BSc(Agri). COS,Chintamani Slide 10: Collected from the centers of diversity, gene bank, gene sanctuaries, farmers fields, markets and seed companies. Basic material for launching a crop improvement programme. May be indigenous (collected within country) or exotic (collected from foreign countries). Prepared for II BSc(Agri). COS,Chintamani Classification of Gene pool : Classification of Gene pool Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation and (4) cross ability in breeding programmes. Slide 12: Area of collection (1) Indigenous and (2) exotic Domestication (1) Cultivated and (2) Wild. Duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation and (4) cross ability in breeding programmes. Slide 13: Prepared for II BSc(Agri). COS,Chintamani Duration of conservation…….. : Duration of conservation…….. (a) Base collections: Plant materials meant for long term storage or conservation are referred to as base collections. For the purpose of regeneration. Regeneration is carried out after a long time depending on the viability of seeds. The seed viability should not drop to less than 95% before regeneration. Base collections contain seeds with 5+1 % moisture content. Seeds are stored in sealed containers at – 18 to – 20 C. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Duration of conservation…….. : Duration of conservation…….. (b) Active collections: The germplasm meant for medium term storage (10 to 15 years) Subjected to regeneration, multiplication, evaluation, distribution and documentation after every 10-15 years. In these collections, routine germination tests are carried out after every 5 to 10 years to assess the reduction in germination percentage. Large samples (50 to 100) have to be grown for regeneration to prevent genetic drift. Stored at around zero degree Celsius temperature and seed moisture should be around 8%. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Duration of conservation…….. : Duration of conservation…….. (c) Working collections. The genetic resources which are stored for short term (3 to 5 years) Regularly used in crop improvement programmes. There is no need to grow such material every year. The seed is stored at 50 C to 100 C with seed moisture content of 8 to 10%. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Slide 17: Prepared for II BSc(Agri). COS,Chintamani Slide 18: Utilisation in breeding (crossability) 1. Primary gene pool : easy to cross, fertile hybrids, useful for breeding 2. Secondary gene pool : partial fertile hybrids with primary gene pool 3. Tertiary gene pool: sterile hybrids with primary pool Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Slide 19: Prepared for II BSc(Agri). COS,Chintamani Slide 20: Prepared for II BSc(Agri). COS,Chintamani Land races : Land races Primitive cultivars selected and cultivated by the farmers from many generations. Features of land races: Land races were not deliberately bred like modern cultivars. Land races have high level of genetic diversity with resistance to biotic and abiotic stresses. Land races have broad genetic base for wider adaptability. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 22: Prepared for II BSc(Agri). COS,Chintamani They differ in adaptation to type, time of seeding, date of maturity, height, nutritive value and other properties. Little response to selection for high yield They are less uniform and low yielders. Obsolete cultivars : Obsolete cultivars Improved varieties of recent past are known as obsolete cultivars. They are the varieties which were popular earlier and now have been replaced by new varieties. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Modern cultivars : Modern cultivars currently cultivated high yielding varieties also known as improved cultivars or advance cultivars. used as parents in the breeding programmes high yield potential and uniformity as compared to obsolete varieties and land races. modern cultivars have narrow genetic base and low adaptability compared to land races. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Advanced breeding lines : Advanced breeding lines advanced cultures which are not yet ready for release to farmers Sometimes they are not very much productive, but valuable for various economic characters. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Wild forms of cultivated species : Wild forms of cultivated species High degree of resistance to biotic and abiotic stresses They can easily cross with cultivated species. Wild forms of many crop species are extinct. They constitute small part of gene pool. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 27: Those naturally occurring plant species which have common ancestry with crops can cross with crop species important sources of resistance to biotic abiotic stresses It is used as last resort in crop improvement programmes, (1) hybrid sterility (2) hybrid viability and (3) transfer of several undesirable genes to the cultivated species along with desirable alleles. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Mutants : Mutants When the desired character not found in cultivated and their wild relatives Natural and induced mutations Extra variability created through induced mutations May not be released as a variety, but they are added in the gene pool. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 29: Prepared for II BSc(Agri). COS,Chintamani Slide 30: Prepared for II BSc(Agri). COS,Chintamani 1. EXPLORATION AND COLLECTION : 1. EXPLORATION AND COLLECTION Exploration : collection from various sources and assembling the same at one place. Collection is essential to reduce the loss of genetic diversity due to genetic erosion and extinction. (1) Sources of collection, (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. Gene bank or germplasm bank: (1) Exploration and collection (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Sources of collection : Sources of collection (1) centers of diversity (2) gene banks (3) gene sanctuaries : tribal areas (4) seed companies and (5) farmers fields. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 2. Priority of collection : 2. Priority of collection Some areas of diversity have been threatened more than others by the danger of extinction. some crop species have more risk of extinction than others. Hence, endangered areas and endangered species should be given priority for germplasm collection. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 3. Agencies of collection : 3. Agencies of collection For Indigenous collections. Crop Research institutes State Agricultural Universities with National Bureau of Plant Genetic Resources, New Delhi For global collection, : collaboration with International Plant Genetic Resources Institute (IPGRI), Rome Italy. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 4. Method of collection. : 4. Method of collection. (1) through expeditions to the areas or regions of genetic diversity (2) by personal visit to gene bank centre (3) through correspondence (4) through exchange of material. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 5. Method of sampling : 5. Method of sampling (1) random sampling, (2) biased sampling. Random sampling: effective in capturing of alleles for biotic and abiotic stresses, Biased sampling : useful in collection of morphologically distinct genotypes. Both procedures should be adopted to tap the maximum genetic diversity of a crop species. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 6. Sample size : 6. Sample size 95% of the total genetic diversity should can be captured from the area of collection. Hence, 50 to 100 individuals should be collected per site with 50 seeds per plant. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Merits and demerits of exploration and collection : Merits and demerits of exploration and collection Merits It helps in tapping crop genetic diversity and assembling the same at one place. It reduces the loss of genetic diversity due to genetic erosion. Material of special interest during exploration trips New plant species during the process of collection Collection also helps in saving certain genotypes from extinction. Slide 39: Prepared for II BSc(Agri). COS,Chintamani Demerits Collection from other countries, sometime leads to entry of new diseases, new insects and new weeds. Collection is a tedious job: uncultivated areas like hills, mountains, river valleys and forests, where the collector faces problems of boarding, lodging and transportation. In the remote areas, the collector, sometimes has to encounter with risk of life. Transportation of huge collections also poses difficulties Slide 40: Prepared for II BSc(Agri). COS,Chintamani 2. CONSERVATION : 2. CONSERVATION Conservation refers to protection of genetic diversity of crop plants from genetic erosion. Two methods: (1) in situ conservation (2) ex situ conservation. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. In situ Conservation : In situ Conservation Conservation of germplasm under natural conditions It requires establishment of natural or biosphere reservoir, national parks or protection of endangered areas or species Main disadvantages. covers only very small portion of total diversity of a crop species, hence several areas will have to be conserved for a single species. Management of such areas also poses several problems This is a costly method of germplasm conservation. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Ex situ Conservation : Ex situ Conservation It refers to preservation of germplasm in gene banks. This is the practical method of germplasm conservation. Main advantages. 1. It is possible to preserve entire genetic diversity of a crop species at one place 2. Handling of germplasm is also easy 3. This is a cheap method of germplasm conservation Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Ex situ Conservation…….. : Ex situ Conservation…….. The germplasm is conserved either (1) in the form of seed, (2) in the form of meristem cultures. Seed conservation is relatively safe, requires minimum space (except coconut, etc) and easy to maintain. Glass, tin or plastic containers are used for preservation and storage The seeds can be conserved under long term (50 to 100 years), medium term (10 to 15 years) and short term (3-5 years) storage conditions. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Types of seeds for storage purpose : Types of seeds for storage purpose (1) Orthodox can be dried to low moisture content and stored at low temperature without loosing their viability seeds of corn, wheat, rice, carrot, beets, papaya, pepper, chcickpea, lentil, soybean, cotton, sunflower, various beans, egg plant and all the brassicas. (2) Recalcitrant. very drastic loss in viability with a decrease in moisture content below 12 to 13% cocoa, coconut, mango, tea, coffee, rubber, jackfruit and oil plam seeds. cannot be conserved in seed banks and, therefore, require in situ conservation. Crop species with recalcitrant seeds are conserved in field gene banks. Conservation of meristem cultures, : Conservation of meristem cultures, meristem or shoot tip bank Advantages: Exact genotypes can be conserved indefinitely free from virus or other pathogens and without loss of genetic integrity It is advantageous for vegetatively propagated crops like potato, sweet potato, cassava, etc., because seed production in these crops is poor. Vegetatively propagated material can be saved from natural disasters or pathogen attack. Long regeneration cycle can be envisaged from meristem cultures. Perennial plants which take 10 to 20 years to produce seeds can be preserved any time by meristem cultures. Regeneration of meristems is extremely easy Plant species having recalcitrant seeds can be easily conserved by meristem cultures. Table . Gene banks of various crops in India : Table . Gene banks of various crops in India Gene banks maintained by various International Crop Research Institutions : Gene banks maintained by various International Crop Research Institutions 3. EVALUATION : 3. EVALUATION Evaluation refers to screening of germplasm in respect of morphological genetical, economic, biochemical, physiological, pathological and entomological attributes. To identify gene sources for resistance to biotic and abiotic stresses viz, earliness, dwarfness, productivity and quality characters. To classify the germplasm into various groups To get a clear picture about the significance of individual germplasm line Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Evaluation…….. : Evaluation…….. requires a team of specialists from the disciplines of plant breeding, physiology, biochemistry, pathology and entomology. list of descriptors (characters) for which evaluation: IPGRI, Rome, Italy. The variation for polygenic characters is assessed by three different methods as given below: By simple measures of dispersion (range, standard, deviation standard error and coefficient of variation) By metroglyph analysis of Anderson (1957) and By D2 statistics of P.C. Mahalanobis (1936) Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 4. DOCUMENTATION : 4. DOCUMENTATION Documentation refers to completion, analysis, classification, storage and dissemination of information. It provides information about various activities of plant genetic resources It provides latest information about characterization, conservation, distribution and utilization of genetic resources It helps explorers, evaluators and curators in the conservation of genetic resources It helps in making genetic resources accessible to plant breeders and other users Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 5. DISTRIBUTION : 5. DISTRIBUTION one of the important activities of genetic resources centres. specific germplasm lines are supplied to the users on demand for utilization in the crop improvement programmes. Distribution of germplasm is the responsibility of the gene bank centre where the germplasm is maintained and conserved. The germplasm is usually supplied to the workers who are engaged in the research work of a particular crop species Germplasm samples are generally supplied free of cost to avoid cumbersome work of book keeping The quantity of seed samples to be sent is usually small, depends on the availability of seed material and demands received for the same and several other factors Proper records are maintained about the distribution of material. After evaluation users should send a report about important characters of the accessions to the distributor who will record the information in the germplasm register for documentation purpose. The germplasm is usually distributed after evaluation by collection centre for one or two crop seasons. It helps in acclimatization and purification of the material. Without distribution to the actual users, there is no point in collection the germplasm. 6. UTILIZATION : 6. UTILIZATION Utilization refers to use of germplasm in crop improvement programme Cultivated germplasm can be used in three main ways (1) as a variety, (2) as a parent in the hybridization, and (3) as a variant in the gene pool. Wild germplasm used to transfer resistance to biotic and abiotic stresses, wider adaptability and sometimes quality such as fibre strength in cotton. main problem viz (1) hybrid inviability - inability of a hybrid to survive, (2) hybrid sterility – inability of a hybrid to produce off spring, and (3) linkage of undesirable characters with desirable ones. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Slide 54: Prepared for II BSc(Agri). COS,Chintamani Slide 55: Achieving Self-Sufficiency in Cereals, Pulses and Oilseeds in India : The Way Forward B.B. Singh, Visiting Professor, GBPUA&T Pantnagar We need political will and innovative science Indeterminate Habit – Pod Maturity : Indeterminate Habit – Pod Maturity Indeterminate plant 123 cm 7 Clusters 6 9 No. of Pods 18 1 + 3 53 + 0 98 + 19 56 98 No. of grains 41 0 + 70 219 + 27 497 + (Immature & black grains % ) 24.22 5.16 100.00 Quality of Grain Produce : Quality of Grain Produce Traditionally grown guar has indeterminate growth habit causes continual flowering and heterogeneous pod maturation, thus resulting in poor grain quality Immature and black seeds in the grain produce of indeterminate cultivars can be as high as 16 % Slide 58: Leaf Determinate Guar GDM – 1 GLDM - 1 You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Plant Genetic Resources plantbreeding Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1653 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: July 13, 2010 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... By: KVN01 (8 month(s) ago) good presentation; touches on all important aspects Saving..... Post Reply Close Saving..... Edit Comment Close By: sekhar_gpb (16 month(s) ago) very nice presentation Saving..... Post Reply Close Saving..... Edit Comment Close By: sekhar_gpb (18 month(s) ago) very nice Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: Prepared for II BSc(Agri). COS,Chintamani Lecture-3 and 4 Domestication & germplasm conservation Slide 2: Prepared for II BSc(Agri). COS,Chintamani Key points for this lecture Domestication Selection under Domestication: 1. Natural i) Environmental selection ii) Environmental selection 2. Artificial Population Types of Selection: (1) directional selection, (2) stabilizing selection and (3) disruptive selection. Germplasm: (1) land races, (2) obsolete varieties, (3) varieties in cultivation, (4) breeding lines, and (5) wild forms and wild relatives. Gene pool concept: (1) primary (GP,), (2) secondary (GP2) and (3) tertiary (GP)) gene pools. Genetic erosion; features Germplasm activities Gene banks Gene sanctuaries Slide 3: Prepared for II BSc(Agri). COS,Chintamani Domestication is the process of bringing wild species under human management Gopher plant (Hevea sp.) Milkweed (Euphorbia lathyrus), Kala jeera (Bunium persicum), Slide 4: Prepared for II BSc(Agri). COS,Chintamani Selection under Domestication When different genotypes present in a population reproduce at different rates, it is called selection. A population may be simply defined as the group of individuals, which mate or can mate freely with each other. Selection is grouped into two types, on the basis of the agency responsible for it. natural and (2) artificial Slide 5: Prepared for II BSc(Agri). COS,Chintamani Natural Selection. The selection that occurs due to natural forces like climate, soil, biological factors (e.g., diseases, insect pests, etc.) and other factors of the environment is called natural selection. In 1962, Nichlson proposed that natural selection may be seen to operate through two mechanisms, viz.; (l) environmental selection and (2) competition. Environmental selection acts against all such genotypes that are unable to cope with the environmental stresses. Slide 6: Prepared for II BSc(Agri). COS,Chintamani Natural selection through competition occurs in crop populations where a plant takes up more water, nutrients or light than another at the expense of the other. Artificial Selection. is carried out by man and is confined to domesticated species. It allows only the selected plants to reproduce, ordinarily .makes plants more useful to man and generally leads to a marked decline in genetic variability in the selected progenies/populations. Types of Selection directional selection, stabilizing selection and (3) disruptive selection. Slide 7: Prepared for II BSc(Agri). COS,Chintamani Directional Selection. When individuals having the extreme phenotype for a trait or a group of traits are selected for, it is called directional selection. Stabilizing Selection. When selection favours the intermediate phenotype and acts against the extreme phenotypes, it is termed as stabilizing selection Disruptive Selection. In each 'ecological niche' a different 'phenotypic optima' is selected for so that the population ultimately consists of two or more recognizable forms; such a selection is called disruptive selection.. Slide 8: Prepared for II BSc(Agri). COS,Chintamani GERMPLASM The germplasm of a crop may be defined as the sum total of hereditary material, i.e., all the alleles of various genes, present in a crop species and its wild relatives. Germplasm consists of the following five types of materials: land races, (2) obsolete varieties, (3) varieties in cultivation, (4) breeding lines, and (5) wild forms and wild relatives. Slide 9: The sum total of genes in crop species important features of PGR Represents the entire genetic variability or diversity available in a crop species. Consists of land races, modern cultivars, obsolete cultivars, breeding stocks, wild forms and wild species of cultivated crops. Includes both cultivated and wild species and relatives of crop plants. Prepared for II BSc(Agri). COS,Chintamani Slide 10: Collected from the centers of diversity, gene bank, gene sanctuaries, farmers fields, markets and seed companies. Basic material for launching a crop improvement programme. May be indigenous (collected within country) or exotic (collected from foreign countries). Prepared for II BSc(Agri). COS,Chintamani Classification of Gene pool : Classification of Gene pool Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation and (4) cross ability in breeding programmes. Slide 12: Area of collection (1) Indigenous and (2) exotic Domestication (1) Cultivated and (2) Wild. Duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation and (4) cross ability in breeding programmes. Slide 13: Prepared for II BSc(Agri). COS,Chintamani Duration of conservation…….. : Duration of conservation…….. (a) Base collections: Plant materials meant for long term storage or conservation are referred to as base collections. For the purpose of regeneration. Regeneration is carried out after a long time depending on the viability of seeds. The seed viability should not drop to less than 95% before regeneration. Base collections contain seeds with 5+1 % moisture content. Seeds are stored in sealed containers at – 18 to – 20 C. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Duration of conservation…….. : Duration of conservation…….. (b) Active collections: The germplasm meant for medium term storage (10 to 15 years) Subjected to regeneration, multiplication, evaluation, distribution and documentation after every 10-15 years. In these collections, routine germination tests are carried out after every 5 to 10 years to assess the reduction in germination percentage. Large samples (50 to 100) have to be grown for regeneration to prevent genetic drift. Stored at around zero degree Celsius temperature and seed moisture should be around 8%. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Duration of conservation…….. : Duration of conservation…….. (c) Working collections. The genetic resources which are stored for short term (3 to 5 years) Regularly used in crop improvement programmes. There is no need to grow such material every year. The seed is stored at 50 C to 100 C with seed moisture content of 8 to 10%. Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Slide 17: Prepared for II BSc(Agri). COS,Chintamani Slide 18: Utilisation in breeding (crossability) 1. Primary gene pool : easy to cross, fertile hybrids, useful for breeding 2. Secondary gene pool : partial fertile hybrids with primary gene pool 3. Tertiary gene pool: sterile hybrids with primary pool Classified on the basis of: (1) area of collection, (2) domestication, (3) duration of conservation (a) Base collection, (b) Active collection, and (c) Working collections. (4) cross ability in breeding programmes. Slide 19: Prepared for II BSc(Agri). COS,Chintamani Slide 20: Prepared for II BSc(Agri). COS,Chintamani Land races : Land races Primitive cultivars selected and cultivated by the farmers from many generations. Features of land races: Land races were not deliberately bred like modern cultivars. Land races have high level of genetic diversity with resistance to biotic and abiotic stresses. Land races have broad genetic base for wider adaptability. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 22: Prepared for II BSc(Agri). COS,Chintamani They differ in adaptation to type, time of seeding, date of maturity, height, nutritive value and other properties. Little response to selection for high yield They are less uniform and low yielders. Obsolete cultivars : Obsolete cultivars Improved varieties of recent past are known as obsolete cultivars. They are the varieties which were popular earlier and now have been replaced by new varieties. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Modern cultivars : Modern cultivars currently cultivated high yielding varieties also known as improved cultivars or advance cultivars. used as parents in the breeding programmes high yield potential and uniformity as compared to obsolete varieties and land races. modern cultivars have narrow genetic base and low adaptability compared to land races. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Advanced breeding lines : Advanced breeding lines advanced cultures which are not yet ready for release to farmers Sometimes they are not very much productive, but valuable for various economic characters. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Wild forms of cultivated species : Wild forms of cultivated species High degree of resistance to biotic and abiotic stresses They can easily cross with cultivated species. Wild forms of many crop species are extinct. They constitute small part of gene pool. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 27: Those naturally occurring plant species which have common ancestry with crops can cross with crop species important sources of resistance to biotic abiotic stresses It is used as last resort in crop improvement programmes, (1) hybrid sterility (2) hybrid viability and (3) transfer of several undesirable genes to the cultivated species along with desirable alleles. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Mutants : Mutants When the desired character not found in cultivated and their wild relatives Natural and induced mutations Extra variability created through induced mutations May not be released as a variety, but they are added in the gene pool. Components of Genetic Resources (1) Land races, (2) Obsolete cultivars, (3) Modern cultivars, (4) Advanced breeding materials, (5) Wild forms of cultivated species, (6) Wild relatives and (7) Mutants. Slide 29: Prepared for II BSc(Agri). COS,Chintamani Slide 30: Prepared for II BSc(Agri). COS,Chintamani 1. EXPLORATION AND COLLECTION : 1. EXPLORATION AND COLLECTION Exploration : collection from various sources and assembling the same at one place. Collection is essential to reduce the loss of genetic diversity due to genetic erosion and extinction. (1) Sources of collection, (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. Gene bank or germplasm bank: (1) Exploration and collection (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Sources of collection : Sources of collection (1) centers of diversity (2) gene banks (3) gene sanctuaries : tribal areas (4) seed companies and (5) farmers fields. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 2. Priority of collection : 2. Priority of collection Some areas of diversity have been threatened more than others by the danger of extinction. some crop species have more risk of extinction than others. Hence, endangered areas and endangered species should be given priority for germplasm collection. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 3. Agencies of collection : 3. Agencies of collection For Indigenous collections. Crop Research institutes State Agricultural Universities with National Bureau of Plant Genetic Resources, New Delhi For global collection, : collaboration with International Plant Genetic Resources Institute (IPGRI), Rome Italy. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 4. Method of collection. : 4. Method of collection. (1) through expeditions to the areas or regions of genetic diversity (2) by personal visit to gene bank centre (3) through correspondence (4) through exchange of material. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 5. Method of sampling : 5. Method of sampling (1) random sampling, (2) biased sampling. Random sampling: effective in capturing of alleles for biotic and abiotic stresses, Biased sampling : useful in collection of morphologically distinct genotypes. Both procedures should be adopted to tap the maximum genetic diversity of a crop species. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 6. Sample size : 6. Sample size 95% of the total genetic diversity should can be captured from the area of collection. Hence, 50 to 100 individuals should be collected per site with 50 seeds per plant. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Merits and demerits of exploration and collection : Merits and demerits of exploration and collection Merits It helps in tapping crop genetic diversity and assembling the same at one place. It reduces the loss of genetic diversity due to genetic erosion. Material of special interest during exploration trips New plant species during the process of collection Collection also helps in saving certain genotypes from extinction. Slide 39: Prepared for II BSc(Agri). COS,Chintamani Demerits Collection from other countries, sometime leads to entry of new diseases, new insects and new weeds. Collection is a tedious job: uncultivated areas like hills, mountains, river valleys and forests, where the collector faces problems of boarding, lodging and transportation. In the remote areas, the collector, sometimes has to encounter with risk of life. Transportation of huge collections also poses difficulties Slide 40: Prepared for II BSc(Agri). COS,Chintamani 2. CONSERVATION : 2. CONSERVATION Conservation refers to protection of genetic diversity of crop plants from genetic erosion. Two methods: (1) in situ conservation (2) ex situ conservation. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. In situ Conservation : In situ Conservation Conservation of germplasm under natural conditions It requires establishment of natural or biosphere reservoir, national parks or protection of endangered areas or species Main disadvantages. covers only very small portion of total diversity of a crop species, hence several areas will have to be conserved for a single species. Management of such areas also poses several problems This is a costly method of germplasm conservation. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Ex situ Conservation : Ex situ Conservation It refers to preservation of germplasm in gene banks. This is the practical method of germplasm conservation. Main advantages. 1. It is possible to preserve entire genetic diversity of a crop species at one place 2. Handling of germplasm is also easy 3. This is a cheap method of germplasm conservation Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Ex situ Conservation…….. : Ex situ Conservation…….. The germplasm is conserved either (1) in the form of seed, (2) in the form of meristem cultures. Seed conservation is relatively safe, requires minimum space (except coconut, etc) and easy to maintain. Glass, tin or plastic containers are used for preservation and storage The seeds can be conserved under long term (50 to 100 years), medium term (10 to 15 years) and short term (3-5 years) storage conditions. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Types of seeds for storage purpose : Types of seeds for storage purpose (1) Orthodox can be dried to low moisture content and stored at low temperature without loosing their viability seeds of corn, wheat, rice, carrot, beets, papaya, pepper, chcickpea, lentil, soybean, cotton, sunflower, various beans, egg plant and all the brassicas. (2) Recalcitrant. very drastic loss in viability with a decrease in moisture content below 12 to 13% cocoa, coconut, mango, tea, coffee, rubber, jackfruit and oil plam seeds. cannot be conserved in seed banks and, therefore, require in situ conservation. Crop species with recalcitrant seeds are conserved in field gene banks. Conservation of meristem cultures, : Conservation of meristem cultures, meristem or shoot tip bank Advantages: Exact genotypes can be conserved indefinitely free from virus or other pathogens and without loss of genetic integrity It is advantageous for vegetatively propagated crops like potato, sweet potato, cassava, etc., because seed production in these crops is poor. Vegetatively propagated material can be saved from natural disasters or pathogen attack. Long regeneration cycle can be envisaged from meristem cultures. Perennial plants which take 10 to 20 years to produce seeds can be preserved any time by meristem cultures. Regeneration of meristems is extremely easy Plant species having recalcitrant seeds can be easily conserved by meristem cultures. Table . Gene banks of various crops in India : Table . Gene banks of various crops in India Gene banks maintained by various International Crop Research Institutions : Gene banks maintained by various International Crop Research Institutions 3. EVALUATION : 3. EVALUATION Evaluation refers to screening of germplasm in respect of morphological genetical, economic, biochemical, physiological, pathological and entomological attributes. To identify gene sources for resistance to biotic and abiotic stresses viz, earliness, dwarfness, productivity and quality characters. To classify the germplasm into various groups To get a clear picture about the significance of individual germplasm line Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Evaluation…….. : Evaluation…….. requires a team of specialists from the disciplines of plant breeding, physiology, biochemistry, pathology and entomology. list of descriptors (characters) for which evaluation: IPGRI, Rome, Italy. The variation for polygenic characters is assessed by three different methods as given below: By simple measures of dispersion (range, standard, deviation standard error and coefficient of variation) By metroglyph analysis of Anderson (1957) and By D2 statistics of P.C. Mahalanobis (1936) Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 4. DOCUMENTATION : 4. DOCUMENTATION Documentation refers to completion, analysis, classification, storage and dissemination of information. It provides information about various activities of plant genetic resources It provides latest information about characterization, conservation, distribution and utilization of genetic resources It helps explorers, evaluators and curators in the conservation of genetic resources It helps in making genetic resources accessible to plant breeders and other users Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. 5. DISTRIBUTION : 5. DISTRIBUTION one of the important activities of genetic resources centres. specific germplasm lines are supplied to the users on demand for utilization in the crop improvement programmes. Distribution of germplasm is the responsibility of the gene bank centre where the germplasm is maintained and conserved. The germplasm is usually supplied to the workers who are engaged in the research work of a particular crop species Germplasm samples are generally supplied free of cost to avoid cumbersome work of book keeping The quantity of seed samples to be sent is usually small, depends on the availability of seed material and demands received for the same and several other factors Proper records are maintained about the distribution of material. After evaluation users should send a report about important characters of the accessions to the distributor who will record the information in the germplasm register for documentation purpose. The germplasm is usually distributed after evaluation by collection centre for one or two crop seasons. It helps in acclimatization and purification of the material. Without distribution to the actual users, there is no point in collection the germplasm. 6. UTILIZATION : 6. UTILIZATION Utilization refers to use of germplasm in crop improvement programme Cultivated germplasm can be used in three main ways (1) as a variety, (2) as a parent in the hybridization, and (3) as a variant in the gene pool. Wild germplasm used to transfer resistance to biotic and abiotic stresses, wider adaptability and sometimes quality such as fibre strength in cotton. main problem viz (1) hybrid inviability - inability of a hybrid to survive, (2) hybrid sterility – inability of a hybrid to produce off spring, and (3) linkage of undesirable characters with desirable ones. Gene bank or germplasm bank: Exploration and collection (1) Sources of collection (2) Priority of collection (3) Agencies of collection (4) Methods of collection (5) Methods of sampling and (6) Sample size. (2) Conservation, (3) Evaluation (4) Documentation (5) Distribution and (6) Utilization. Slide 54: Prepared for II BSc(Agri). COS,Chintamani Slide 55: Achieving Self-Sufficiency in Cereals, Pulses and Oilseeds in India : The Way Forward B.B. Singh, Visiting Professor, GBPUA&T Pantnagar We need political will and innovative science Indeterminate Habit – Pod Maturity : Indeterminate Habit – Pod Maturity Indeterminate plant 123 cm 7 Clusters 6 9 No. of Pods 18 1 + 3 53 + 0 98 + 19 56 98 No. of grains 41 0 + 70 219 + 27 497 + (Immature & black grains % ) 24.22 5.16 100.00 Quality of Grain Produce : Quality of Grain Produce Traditionally grown guar has indeterminate growth habit causes continual flowering and heterogeneous pod maturation, thus resulting in poor grain quality Immature and black seeds in the grain produce of indeterminate cultivars can be as high as 16 % Slide 58: Leaf Determinate Guar GDM – 1 GLDM - 1