Selection parameters in tapioca (Manihot esculenta Crantz)

Abstract

During a biometrical study conducted on 20 divergent types of tapioca (Manihot esculenta Crantz) in the premises of Central Tuber Crops Research Institute at Trivandrum, as a postgraduate programme of the Kerala Agricultural University, useful informations on the selection parameters become available. Accordingly, it was found that harvest index should be the best reliable criterion for effecting selection in favour of a desirable genotype from among others in a genetically heterogenic base population. Further, it is proposed that potentially high tuber yielders in the crop could be identified among relatively short statured ones with more number of large sized leaves that have become completely developed sufficiently early during development of the shoot. In addition , a tendency for relatively more number of leaves to become abscissed towards the time of harvest should also be considered as a positive sign of high tuber yield