Breeding of Vegetable, Spice and Tuber crops (2+1)

Improvement of Local Varieties

• Pureline selection is the favourite method for the improvement of local varieties that have considerable genetic variability.
• A large number of varieties have been developed by this method.
  
• Some example of such varieties are, NP4 and NP52 wheat, NP11 and NP12 linseed (Linum usitatisssimum), T1 cowpea (Vigna unguiculata) and T1 mung (V.radiata); these are pureline selection from old local varieties.
  
• Pusa Sawani bhindi (Okra; Abelmoschos esculentus) is a selection from a local variety collected from Bihar; it showed an acceptable level of field resistance to yellow mosaic virus.

Improvement of Old Pureline Varieties

• Purelines become variable with time. Often selection is used to isolate new pureline varieties from such genetically variable purelines.
  
• Some examples of pureline varieties isolated from old pureline are, Chafa (from No. 816) gram; Jalgaon 781 (from China Mung 781), Khargone 1 (from K119-56), Pusa Baisakhi (from T44), CO2 (From PLS 365/3) and CO3 (From PLS367) mung; and CO2 (from P160, CO3 (from PLS364) and B76 (from No. 1766) urd (Vigna mungo).
• Sometimes off – type plants appear in purelines. Such off-type plants may be selected to develop new pureline varieties.
• A dwarf off-type plant was selected from the tall scented pureline variety of rice Kalimoonch 64, and released as a new pureline variety Shyama.