Introduction of plant breeding

Definition

Plant breeding is the art and science of improvement of agricultural crops in order to feed the ever-increasing population. Improvement of crop means changing in genetic makeup/heredity of a plant.
The one who is engaged in plant breeding is called as plant breeder. The role of plant breeder is to combine the desired characters in one plant in order to make high-yielding, input-responsive, disease resistant, drought resistant, etc.
Plant breeding is practiced since ancient time. It was more an art, however, after the Mendel’s work (during 1800s) it is more a science.

Scope of plant breeding

Plant breeding has vast scope in enhancement of productivity of crop plants.
Plant breeding can improve the quality as well as production of seed crops, oil seed, pulses and vegetables.
Through the plant breeding the desired alleles in a population can be accumulated in crop plant.
It has scope to improve the crop management practices.

Objectives of plant breeding

Plant breeding has following (but not limited to) objectives

Improvement in quantity

Grain in maize, jowar, bajra, etc.

Improvement in quality

Size, shape and color of grains
Cooking quality of rice
Milling and baking qualities of wheat
Malting in barley
Protein content in pulses
Shape, size and flavor of fruits
Keeping quality of vegetable
Oil content in oilseeds
Length, strength and fitness of fiber in cotton

Abiotic stress

Drought
Salinity
Temperature
Frost

Disease and pest resistance

Rust resistance in wheat
False smut resistance in rice

Elimination of toxic substances

Lathyrogen (neurotoxin) content in Lathyrus sativus (Khesari lentil)
Hydrogen cyanide in jowar
Cucurbitacin in cucurbits
Erucic acid in Brassicas

Synchronizing maturity

In pulses, e.g., Black gram, mung bean several pickings are required.

Development of photo and thermo-insensitive varieties of wheat and rice to extend their cultivation on new areas.
Change in maturity duration
Desirable changes in agronomic traits