Bulk Breeding Method

it is also one of the breeding method in which bulking done for several generation i.e upto 6 generation, selection will start after F6 generation

1. Handling of Segregation Population: Bulk Breeding Method Dr. Rajendragouda Patil Assistant professor Genetics and Plant Breeding School of Agricultural Sciences and Technology (SAST), NMIMS, MPTP Shirpur

2. Hybridization: crossing between genetically dissimilar plants. Intervarietal (two varieties or genotypes of same species) Interspecific (two species of the same genus) Intergeneric (two genera of the same family) Hybridization uses- 3 ways To combine several desirable traits in to single genotype To create vast genetic variability To develop hybrid varieties for commercial cultivation Methods to handle segregating population Pedigree breeding method Back cross breeding method Bulk breeding method

3. Bulk breeding method In this method F2 and subsequent generations are grown in bulk up to F5 without artificial selection is known as Bulk breeding method This method is given by Nilson Ehle in 1908. Also known as mass method or population method or evolutionary method of crop improvement method. After F6 generation individual plant selection is practiced.

4. Features Mainly used to self pollinated crops (when both the parents have good agronomic traits) Population handled by bulk method (F1 to F5) and IPS from F6 onwards. Usually 5-6 years of bulking practiced In this method natural selection (bulking period) and artificial selection (IPS) operates It changes gene frequencies in population, hence it is called as “evolutionary method of crop improvement” Genetic constitution: homozygous and homogenous

5. Procedure Steps: Bulking period (F2-F5) Progeny selection and isolation of superior progeny (F6-F8) Multilocation trials of superior progeny (F9-F14) Release of best progeny as variety

6. Variety A Variety B Procedure Parents F 1 F 2 F 3 F 4 F 5 Bulk plot Bulk plot Bulk plot Bulk plot Bulk plot Bulking Period

7. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - F5 F 6 F 7 F 8 F 9 -F 14 Space Planted Preliminary yield trials Head to rows Yield trials Progeny selection (Multi-location tastings) Release of Variety

8. Merits and demerits SN Merits Demerits 1. Simple, convenient and less expensive Longer time to develop new variety 2. Natural selection (deletes undesirable traits) Due to short term bulking, natural selection has little effective 3. Chance of obtaining transgressive segregants more than pedigree method Large number of progenies have to be selected at the end of bulking 4. No chance of gene elimination There is chance of natural selection acts against superior traits 5. Progeny selection gives better variety 6. No pedigree record maintained

9. Achievements Barley in USA: ARIVAL, BEECHER,GLACER & GEM ( Altas X Vaughn) Brown Mustard: Narendra Rai

10. Single seed descent method (SSD) A breeding method used for segregating populations of self pollinated crops in which plant are advanced by single seeds from on generation to other referred as SSD Suggested by Goulden (1939) Later it was applied by Grafius (1965) in oats, Brim (1966) in Soybean. It is modified bulk breeding method

11. Variety A Variety B Procedure Parents F 1 F 3 Bulk plot Bulk plot F 2 F 5 IPS F 6 - F 8

12. Merits and demerits SN Merits Demerits 1. Simple , convenient and less expensive Not provide opportunity for to select superior plant till F 5 2. Crosses can be evaluated through this method Frequency of getting desirable genotypes in advanced generation is reduced 3. Able to remain considerable variability Applicable to self-pollinated crops . 4. The material can be advanced by growing the same in green house