Mass selection and pure-line selection are two important breeding methods used for soybeans in the last five years. Hybridization techniques like pedigree method, bulk population method, single seed descent method, and backcrossing are also used. These methods involve crossing parental lines to create variation, then self-pollinating and selecting progeny over multiple generations to develop pure lines with desired traits.

1. SOYBEAN BREEDING METHODS USED IN THE LAST FIVE YEARS
By
MUHAMMAD ANAS
Roll No.250 BSc (Hon) 7th
semester
Departmentof Plant Breedingand Genetics
Submittedto
Prof. Dr. FARHATULLAH SIR
Acting Deanin the Faculty of Crop ProductionSciences
The University of Agriculture Peshawar Pakistan

2. Table of Content
S. No Title Page
1. SOYBEANBREEDING
1. Setting objectives
2. Form the genetic base
3. Genetic variation in soybean
2. BREEDIND METHODS IN SOYBEAN
 Introduction
 Selection
 Types of Selection
- Mass Selection
- Pure line Selection
 Hybridization
 Pedigree method
 Bulk population
 Single SeedDecentMethod
 Back cross
3. Conclusion
4. References

3. Basic steps in plant breeding:
 Objectives
 Germplasm
 Selection
 Evaluation
Breeding objectives:
 Food (yield and nutritional value),
 Feed,
 Fiber,
 Pharmaceuticals,
 Landscape,
 Industrial need (e.g. Crops are being produced in regions to which they are not native).
BREEDING METHODS OF SOYBEAN USED IN THE LAST FIVE YEARS
Introduction:
 Introduced from another geographical region.
Selection:
 Individual plants or groups of plants are selected from heterogeneous plant introductions
and a new number is assigned and released for commercial use.
 The second major phase of soybean breeding in the U.S.
 For example, the variety Flambeau was the result of selection from the within the PI
Manchu.
Types of Selection:
 Mass Selection and
 Pure-line selection.
 Mass Selection:
 In mass selection, a group of homozygous plants are selected on the basis of
phenotype, and harvested.
 The seed are combined without progeny testing.
 The resulting mixture is known as a mass selection.

4. The variety developed by mass selection is generally uniform for physical
features like maturity, but varies in yield, size, quality, or other quantitative
inherited characters (Poehlman, 1987).
 Pure-line selection(theory):
 Established by the Danish Botanist Johannsen in 1903 working with a mixed
lot of common bean.
 Also known as single plant selection.
 The progeny descendant solely by self-pollination from a single homozygous
plant – pure line.
Characteristics/significance of pure line:
 A variety developed by pure line selection is more homozygous
than a variety developed by mass selection, because….
 All plants in the variety will have the same genotype. (poehlman,
1987).
Hybridization:
 The most important aspect of modern soybean breeding: Successful and efficient
artificial hybridization.
 Artificial hybridization is a breeding method that involves a cross between two parental
lines.
Hybridization in soybean:
 A self-pollinated crop, has <1% natural outcrossing.
 Parental lines of the initial crosses are PI’s or selections from PI’s.
 Selection of a pure line is made from an advanced generation following the cross
(poehlmn, 1987).
Pure lines after hybridization:
 Hybrid populations are inbred for several generation to obtain homozygous plants.
 Progeny of each individual plant is evaluated to find transgressive segregates, and
 Superior homogeneous lines are released as pure lines.
Several methods are used for advancing progenies to homozygosity after hybridization
Pedigree method:
1. Selecting superior recombinant pure lines for release as new
cultivars.

5. 2. Selection for the desirable traits is started in F2 generation
and…
3. The pedigree of the individual selected plants is maintained in
successive generations until genetic purity is reached.
Bulk population:
Exploitation of natural selection for adaptation to new
environments (and sometimes for disease resistance) as plants
are grown in bulk for several generations in the selective
environment and then the individual F2 or F6 selections are made
to established new pure lines.
Selection seed descent:
A method originallyproposedfor soybeans(brim,1966)
1. One seed from each F2 plant is advanced to the next
generation, and
2. The process is repeated in succeeding generations, and as
rapidly as possible using the greenhouse or winter nurseries
until the desired level of inbreeding is attained and new pure
line cultivars are selected.
Back cross:
1. A form of recurrent hybridization used to incorporate a single
superior gene to an otherwise desirable variety.
2. A soybean strain with a desirable gene is crossed as a donor
parent to an otherwise superior variety (recurrent parent) that
lacks that specific gene, and the F1 is the backcrossed to the
recurrent parent.
3. This process is continued for several backcross generations
selecting for the desired trait at each generation until the
homozygosity reaches to 97-99% of the genes of the recurrent
parent in addition to the incorporated gene (Wilcox, 1983;
Poehlman, 1987).
CONCLUSIONS
 Soybeanisan importantplantfor humansand animal nutritiondue toit’slarge amountsof
protein,lipid,carbohydrates,minerals,vitamins,andfibers.
 Soybeanoil isthe majoredible oil usedinthe USforproducingsaladdressings,bakingand
fryingfats,margarines,saladandcooking oils.
 Soybeanare the most significantdietarysource of isoflavones,whichare naturallyoccurring
plantcompoundscommonlyreferredtoas phytoestrogenandnamedfortheirsimilarityin
structure to the estrogenmoleculeandabilitytobindtothe estrogenreceptor.
 Soybeanisa majorworldwide commodity,the thirdmostvaluable cropandthe most important
legume globally.

6.  Soybeanmeal isthe number-oneproteinsource usedinthe poultryandlivestockindustries
throughoutthe world.
 Soyflouris a goodsubstitute for10 to30% of the wheatflourinsweetandrichbakedgoods,
such as cookies,softyeastbreadsandquickbreads.
 Soybeanmeal isthe primarysource of inexpensive dietaryproteinandnutrientsforfarm
animals’ production.
 References
 "Glycine max". Encyclopedia of Life. Retrieved February 16, 2012.
 ^ Generally written in katakana, not kanji.
 ^ "Glycine max". Multilingual Multiscript Plant Name Database. Retrieved February 16,2012.
 ^ a b Riaz, Mian N. (2006). Soy Applications in Food. Boca Raton, FL: CRC Press. ISBN 978-0-8493-
2981-4.
 ^ "Soybean meal". Retrieved April 16, 2019.
 ^ a b Hymowitz, T.; Newell, C.A. (July 1, 1981). "Taxonomy of the genusGlycine, domestication and
uses of soybeans". Economic Botany. 35 (3): 272–88. doi:10.1007/BF02859119. ISSN 0013-0001.
 ^ Singh, Ram J.; Nelson, Randall L.; Chung, Gyuhwa (November 2, 2006). Genetic Resources,
Chromosome Engineering, and Crop Improvement: Oilseed Crops, Volume 4. London: Taylor &
Francis. p. 15. ISBN 978-0-8493-3639-3.
 Bhattacharya and Ram (1995)
 Singh et al. 1993
 Hartwig (1993)
 Dr. P.S Shukla soybean breeder
 Qian et al. (1996)
 Singh et al. (1974b)