Biometric analysis of phenotypic characters of potato shoot-tips recoveredfrom tissue culture, dimethyl sulphoxide treatment and cryopreservation

A biometric approach partly involving principal component analysis has been used to examine the changes in phenotypic characters of shoot-tip derived potato plants recovered from tissue culture, dimethyl sulphoxide (DMSO) and cryopreservation in comparison with field-grown tuber-derived plants. Ther e were significant differences in the quantitative characters height and tu ber weight in the cryopreserved plants compared to those derived from DMSO treatment and tissue culture. These three experimental groups were shown to significantly differ from field-grown plants in the characters, tuber weig ht followed by height and length of petiole. The use of biometrics as an an alytical approach in genetic stability assessments of plants recovered from cryopreservation to relatively small sample sizes is discussed.