Role of Various Genetic Concepts and Principles in Crop Improvement
Essential for normal growth and development of living organisms. Leads to production of identical progeny in asexually propagated crop.
It generates variability through recombination and segregation of genes, also maintains chromosome number constant in a species.
3) Chromosome Number:
Useful in transfer of genes from one species to another and structure development of hybrid and development of alien addition and alien substitution lines.
4) Structural Chromosomal:
Play an important role in formation of new species and change transfer of small chromosome segment from one species to another.
5) Numerical Chromosomal:
It is useful in inter specific and inter generic gene transfer, overcoming sterility in such hybrids, conservation of heterosis, development of new crop species etc.
6) Gene Interaction:
It helps in the study of inheritance and gene transfer. Sometimes, it leads to production of new phenotypes.
Linkage affects genetic variances, genetic correlation between characters and efficiency of selection.
8) Chrossing- over:
It releases genetic variability by forming new gene combinations. Variability is essential for improvement by selection.
It affects the efficiency of selection. If the side effects of a gene are desirable, it helps in crop improvement and vice versa.
10) Penetrance and Expressivity:
Help in selection of elite types in the breeding population.
11) Cytoplasmic Inheritance:
It helps in the development of cytoplasmic male sterility for use in development of hybrids. Also adds to variability through mutation of plasma genes. i.e Chloroplast and mitochondria DNA.
They are useful in improving yield, quality, resistance to biotic and abiotic factors, generating new variability developing male sterility , overcoming self incompatibility etc.