Isozyme characterization and indexing of in-vitro raised nucellars in Citrus rootstocks

In 3 recommended Citrus rootstocks, viz. Cleopatra, Pectinifera and Rough lemon, in-vitro raised nucellar seedlings have been reliably characterized on the basis of peroxidase and amylase isozyme systems. Both anodal and cathodal bands were observed for peroxidase, while only one cathodal band was observed for amylase in all the nucellar seedlings. The nucellars could be distinguished from the zygotic seedlings on the basis of banding pattern of different isozymes. The nucellars were serologically indexed and found to be free from CTV, Exocortis and Greening BLO. Hence, isozyme studies can be used as a powerful tool for the characterization of in-vitro raised nucellar seedlings in Citrus as well as for other fruit plants. The uniform and disease-free nucellars can further be utilized for economic and commercial Citrus production.