New varieties are the results of Plant breeding experiments
The main aim of plant breeding is to produce new crops or varieties superior to the existing ones.
Classical plant breeding uses deliberate interbreeding (crossing) of closely or distantly related individuals to produce new crop varieties or lines with desirable properties. Plants are crossbred to introduce traits/genes from one variety or line into a new genetic background. The new varieties are being developed to incorporate following desirable characteristics:
- Resistance to diseases
- Resistance to pests
- Higher yield
- Short duration and early maturing quality.
Plant breeding experiments provides improved variety
The plant breeder achieves this by artificial crossing or hybridization. Using this technique, two or more varieties of plants can be combined. Let us assume that one variety of a crop plant may be resistant to a particular disease, while another variety of the same crop may be high–yielding. By artificially crossing the two varieties, a new plant variety combining the two desirable characteristics, high–yielding as well as resistant to disease, can be produced.
For example, a mildew–resistant pea may be crossed with a high–yielding but susceptible pea, the goal of the cross being to introduce mildew resistance without losing the high–yield characteristics. Progeny from the cross would then be crossed with the high–yielding parent to ensure that the progeny were most like the high–yielding parent, (backcrossing). The progeny from that cross would then be tested for yield and mildew resistance and high–yielding resistant plants would be further developed. Plants may also be crossed with themselves to produce inbred varieties for breeding.