What is Plant Breeding
Plant Breeding
Plant breeding in a simple
language is genetic improvement of plants for the best economic productivity.
It could also be defined in terms of art and the Science of changing and
improving the heredity of plants.
Plant breeding was practiced
first when people learned to look for superior plants to harvest for seed; thus
selection became the earliest method of plant breeding. Primitive efforts in
plant selection contributed much to the evolutionary development of each of the
cultivated crops. These all efforts were done unintentionally. As human
knowledge about plants increased, people were able to select more intelligently
with the discovery of sex in plants, hybridization was added to breeding
techniques. Although hybridization was practiced before the time of Mendel’s
experiments provided a basis for understanding the mechanism of heredity and
how it may be manipulated in the development of improved varieties. A more
precise explanation of the heredity mechanism has become possible in recent
years with the explanation in our knowledge of molecular genetics.
The art of plant breeding lies in
the ability of the breeder to observe differences that may have economic value
in plants of the same species. The breeders of the old times relied largely on
their skill and judgment in selecting the superior types. Many breeders were
good observers, quick to recognize variations among plants of the same species,
which could be used as the basis for the establishing new varieties. For them,
plant breeding was largely an art. Many of the early breeders use to grow and
multiply the plants that accidently appeared as off-type in their fields or
gardeners. Some, like Luther Burbank, were professionals who searched far and
wide for unusual plant types that could be developed and exploited commercially.
As the breeder’s knowledge of
genetics and related plant sciences progressed, plant breeding became less of
an art and more of a science. No longer was it necessary for breeders to rely
so completely on their skill in finding chance variations with which to
establish new varieties. It now has become possible to plan and create new
types more or less at will. Through scientific knowledge breeders have the
background to manipulate and to direct the inheritance of plants. Although
skill in the art of selection is important to the modern plant breeder just as
it was to the breeder of the past, now skill alone is not enough. Modern plant
breeding is based on a thorough understanding and utilization of genetic
principles. It presuppose knowledge of the botanical characteristics of the
species, of plant disease and their epidemiology of insect pests that feed upon
the different plant species, of physiological factors related to adaptation of
plants, and of biochemical characteristics affecting utilization and nutritive
value. Without this precise knowledge and background, modern breeders could
neither explore nor comprehend the vast range of the breeding problems
involved. A modern plant breeder therefore, at a time, needs to be a
geneticist, cytogeneticist, botanist, pathologist, entomologist, physiologist,
biochemist and statistician. This age has no room for hit and miss methods in
breeding, which are costly, inefficient and time consuming. It is essential
that the modern breeder have training in important areas of knowledge related
to plant breeding. These sciences are the tools with which the plant breeders
work. The plant breeder uses his knowledge obtained from these disciplines of
science to evolve new varieties and the plant germplasm available to the
breeder acts as raw material for this purpose.
