Mass Selection

Desirable plants are selected purely based on phenotype and pooled. They are allowed to be grown in mass in next generation. Further selections are made in 3-4 such generations to consolidate desirable characters by ignoring plants with undesirable character at each selection. Individual progeny is not tested and propagated. This method is generally suitable for highly cross pollinated crops like maize.

Pure Line Selection

Single plant with desirable characters from genetically divergent population is selected and it is selfed. In second generation, the seeds of individual selfed plants are sown in separate lines and further selections are made. Pure line selection consolidates a particular character and results in substantial improvement of desirable trait. This method is usually followed in self pollinated crops.

Selfing

Process of covering the flower or inflorescence by paper covers in order to avoid fertilization by external pollen. This makes only self pollination possible.