The document outlines various plant breeding methods, including inbreeding, hybrid breeding, backcrossing, mutation breeding, and genetic engineering, aimed at enhancing crop yield and resistance to pests and environmental stress. It highlights significant contributions from scientists in the field, such as Gregor Mendel and Norman Borlaug, and key innovations in plant breeding techniques throughout history. Additionally, it discusses concepts like gene pools and resistance mechanisms that are important in breeding practices.

1. PLANT BREEDING
INNOVATIONS AND SCIENTISTS IN PLANT BREEDING
Dr. K. Vanangamudi
Formerly Dean (Agriculture),
Dean Adhiparasakthi Agricultural College,
Professor & Head,
Seed Science & Technology, TNAU, Coimbatore

2. PLANT BREEDING
 Manipulation of plants qualities to create new
varieties with desired characteristics.
Objectives
 To enhance crop yield.
 To cultivate plants with desired characteristics.
 To impart a pest & disease resistance.
 To develop plants to tolerate extreme environmental
stress.

3. Plant Breeding Types
1.Inbreeding
 Self-fertilization method is followed
 Progeny produced is the same generation after
generation.
 Helps to preserve the original traits.
2. Hybrid Breeding
 Two different plants (varieties/species/genus) are crossed
to produce the offspring that is better in productivity and
qualities than the parents.

4. 3. Backcrossing
 Plant with desired traits is crossed with a plant that does
not have the desired traits, but has several other traits.
4. Mutation Breeding
 Mutations in plant genes result in new varieties.
 Mutations be induced by exposing them to chemicals and
radiation.
5. Genetic Engineering
 Production of crops with desirable traits by inserting the
gene of interest within the crop DNA.
 Known as genetically modified crops (Bt crops)

5. INNOVATIONS & SCIENTISTS
 Gregor Mendel (1822–84) is the father of genetics and plant breeding
 Gregor Mendel (1866) experimented with plant hybridization and
discovered laws of inheritance while working with garden pea.
 First to develop inter – specific hybrid between Sweet William and
carnation (Dianthus barbatus x D.caryophyllus) – Fairchild’s mule -
Thomas Fairchild (1717).
 Vilmorins principle of progeny testing - used progeny test in
improvement of sugarbeet - Vilmorins (1856)

6.  Rimpu (1890) made first inter generic cross between bread wheat and
rye resulted in triticale (DT-46 variety of triticale).
 In 1900, De Vries (Holland), Correns (Germany) & Tschermark (Austria)
rediscovered Mendel’s law of inheritance independently.
 In 1903, Johannson (Danish botanist) developed pure – line concept.
Terms genotype and phenotype was coined in 1909 by Johannson.
 Shull, G.H & East, E.M. (1908) – over dominance hypothesis of
heterosis in maize.
 Devenport, C.B. (1908) proposed dominance hypothesis of heterosis.

7.  Jones, D.F. (1917): Made first double cross in maize. First used male
sterility in the development of hybrids.
 Vavilov, N.I. (Russian Geneticist) (1926) identified centres of crop
diversity (Centre of origin) and Law of homologous series of
variation/Law of parallel variation. Identified 8 main centers and 3 sub
centers of crop diversity.
 Karpechenko (Russia) – 1928 –developed first inter generic hybrid
between radish and cabbage.
 Nagaharu, U. (1935) – Proposed origin of tetraploid species of Brassica
using a triangle i.e. U’s triangle.

8.  Painter, R.H. (1951) –Found three mechanisms – Non-
preference, Antibiosis, Tolerance of insect resistance in
crop plants.
 Flor, H.H. (1956) proposed gene for gene hypothesis in flax
(Line seed) for flax rust caused by Malampsora lini.
 Vander Plank, J.E. (1963) proposed concept of vertical and
horizontal resistance.
 Norman, E. Borlaug (1964): Developed high yielding semi –
dwarf varieties of wheat – Father of Green revolution.

9.  In 2000, genome sequencing of Arabidopis thaliana was done. First
genome sequenced plant.
 While in 2002, genome sequencing of Rice.
 2005 – GOI – Approved cultivation Bt cotton in Punjab, Haryana and
Rajasthan.
 Nobilisation of Indian canes by C.A. Barber and T.S. Venkatraman, SBI,
Coimbatore) Saccharum officinarun (Noble cane) x Saccaharum barberi
(Indian cane).
 Transferred thick stem and high sugar contents from tropical noble
cane to north Indian cane. This is known as Nobilisation of Indian
canes.
 Saccaharum spontaneum – wild species resistant of diseases.

10.  Term apomixis – Winkler (1908)
 Self-incompatibility was coined by Stout (1917).
 Koelreuter, first reported self-incompatibility in Verbascum
phoenceum.
 Gametophyte system of SI was discovered by East and Mangeosdorf
(1925) in Nicotina sanderae.
 Sporophytic self incompatibility system was first discovered by
Hughes and Babcock (1950) in Crepis foetida and Gerstel (1950) in
Parthenium argentatum (Guayule)
 Koelreuter (1763) first reported male sterility in flowering plants.

11.  Gene pool concept proposed by Harlan and De Wet (1971).
 Gene pool consists of all the genes and their alleles present in all
such individuals which hybridize with each other.
 Primary gene pool (GP1): Intermating is easy leads to production
of fertile hybrids.
o GP1 – Easily crossable
 Secondary gene pool (GP2): Partial fertility on crossing with GP1
plants.
 Tertiary gene pool (GP3): Sterile hybrids on crossing with GP1
plants.

12.  Term micro centre by Harlan, 1951
 Term primary centres of origin was proposed by Vavilov.
 Mega centre theory was proposed by Zhukovsky.
 Centre and noncentre concept was proposed by Harian
 Vander Plank, J.E. (1963): Developed the concept of vertical and
horizontal resistance.
 Pure line selection: Given by Johansen (Danish biologist.
 Single seed descent method was suggested by Goulden (1939).
 Concept of SSD in oats in 1965 by – Graphius and in soybean by
C.A.Brim (1966).

13.  Bulk breeding method Concept was developed by Nilsson Ehle (1908).
 Recurrent selection” was coined by Hull (1945).
 Procedure of recurrent selection was described by Jenkins (1940).
 Recurrent selection for SCA (Narrow based test cross) was proposed
by F.H.Hull (1945).
 Recurrent selection for GCA (Broad based test cross) was first
suggested by Jenkins
 Reciprocal recurrent selection proposed by R.E. Comstock, H.F.
Robinson and P.H.Harvey (1949).

14.  In progeny selection (Ear to row method) in maize was first proposed
by Hopkins.
 Modified ear to row method was proposed by Lonquist.
 Commercial cultivation of synthetics first suggested in maize by
Hayes and Garber (1919).
 G.H.Shull was the first to produce a single cross hybrid in maize.
 Top cross method was suggested by Davis (1927). Exploitation of
hybrids in tobacco was carried out by Koelreuter.
 Heterosis was coined by G.H. Shull (1914).
 First hybrid rice was developed in 1976 at China by Yuan Long Ping
(Father of hybrid rice).

15.  Term mutation was coined by Hugo De vries in 1900.
 The scientific study of mutation was started in 1910
by Morgan and his workers.
 Mutagenic action of X-rays was discovered by
Muller (1927) on Drosophila and awarded noble prize
in 1946.
 Mutations action of gamma rays given by Stadler
(1928) in barley and maize.

16.  Heterobeltiosis, term first coined by Fonseca (1965) in wheat
diallel analysis
 Useful Heterosis was used by Meredith and Bridge (1972)
 Overdominance was coined by Hull (1945) in Maize.
 Ideotype was proposed by Donald (1968) in wheat.
 Epistasis is a term originally proposed by Bateson (1909).

17.  Clone – Webber
 Genome – Winkler
 Amphimixis – Weismann
 Polyembryony – Leewenhock
 Parthenocarpy – Null
 Parthenogenesis – Owen
 Selection and heterstyly – Darwin
 Tripel fusion – Strausburger
 Colchincine discovered by Blakslee