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24

CHAPTER 2

selection practices to produce farmer-selected varieties, evidence of deliberate plant manipulation for
the purposes of improvement are few. Archeological
findings occasionally reveal some ancient practices
which indicate that plant manipulation beyond phenotypic selection among natural variability occurred.
Babylonians are said to have perceived the role of
pollen in successful fruit production and applied it
to the pistils of female date palms to produce fruit.
The Assyrians did likewise in about 870 BC, artificially
pollinating date palms.

2.4 Early pioneers of the theories and
practices of modern plant breeding
Plant breeding as we know it today began in earnest
in the nineteenth century. Prior to this era, a number of groundbreaking discoveries and innovations
paved the way for scientific plant manipulation.
Some of the early pioneers of plant breeding
include the following:
Rudolph Camerarius (1665–1721). Rudolph
Camerarius was a professor of philosophy at the
University of Tubingen in Germany. He conducted research that contributed to establishing
sexual differentiation, defining the male and
female reproductive parts of the plant. His seminal work, De sexu plantarum (On the sex of
plants), was published in 1694 in a letter to a colleague. Camerarius’s work also described the
functions of the reproductive parts in fertilization
and showed that pollen is required for this key
process in heredity.
Joseph Gottlieb Koelreuter (1733–1806). German
botanist, J.G. Koelreuter became professor of
natural history and director of the botanical gardens
in Karlsruhe in 1764. He was a pioneer in the
application of the discovery of sex in plants as a
vehicle for their genetic manipulation. He observed
that the hybrid offspring generally resembled the
parent that supplied the pollen as closely as the parent on which seed was borne. Koelreuter conducted
the first systematic experiments in plant hybridization, using the tobacco plant as subject. He recognized the role of insects and wind in pollination of
flowers, and also conducted experiments to study
artificial fertilization and development in tobacco
plants. The golden rain tree genus (Koelreuteria) is
named in his honor.

Louis de Vilmorin (1902–1969). Louis de Vilmorin
was a noted French seedsman. His experiments in
heredity contributed to our understanding of the
cause of variation. Vilmorin conducted studies in
plant improvement in vegetables using a method
called genealogical selection, which is the modern
breeding equivalent of progeny testing. He recognized that new varieties of plants could be developed by selecting certain characteristics, which
would then be transmitted through genealogy to
the progeny. In 1856, he published his “Note on
the Creation of a New Race of Beetroot and Considerations on Heredity in Plants”, which laid the
theoretical groundwork for the modern seed breeding industry. The modern day company Vilmorin is
a major player in the global seed industry; along
with its international subsidiaries it is ranked among
the top five largest seed companies in the world.
The company is also credited with producing the
first seed catalog for farmers and academics, among
other significant publications.
Thomas Andrew Knight (1759–1838). This British
horticulturalist and botanist conducted basic
research in plant physiology that led to the discovery of the phenomenon of geotropism, the
effects of gravity on seedlings. He also showed
how decay in fruit trees was transmitted through
grafting. In terms of practical crop improvement,
Knight conducted research in the breeding of
horticultural plants, including strawberries, cabbages, peas, apples and pears. The “Downton”
strawberry that he developed is noted in the pedigree of most of the important modern strawberries. He is credited with pioneering work in
the science of fruit breeding. In 1797 he published a Treatise on the culture of apple and pear.
Knight is also said to have demonstrated segregation for seed characters of the garden pea but,
unfortunately did not offer an explanation for the
event as Mendel eventually did.
Carl Linnaeus (1707–1778). A Swedish botanist,
physician, and zoologist, Carl Linnaeus is most
noted for his work in plant taxonomy, which led to
the development of his enduring conventions for
naming living organisms, the universally accepted
binomial nomenclature, also called Linnaean taxonomy or the scientific classification of organisms.
The binomial nomenclature classifies nature within
a hierarchy, assigning a two-part name to an individual, a genus and a species (specific epithet). His
work was published in his most noted publication
Species Plantarum. There are specific rules and