In this report seven different commercial potato cult ivars (Solanum tuberosum L.) were used to determinate the proper size of meristem in order to eradicate potato virus X (PVX). Using the larger meristem (0.4 mm), the survival, number of plantlets developed and their relative growth rate were higher than the shorter ones (0.2 mm). However, potato cultivars reacted differently.
On the other hand, PVX - free plants resulting from the small apical meristem size was greater (47.4 %) than those of large size (21.2 %).
Shoot tips 1.0 mm long excised from renewed growth of nodal segments incubated under complete darkness for 2 weeks resulted in highest percentage of PVX- eradication in most tested potato cvs. compared with continuous light.
Potato cvs. Cara, Spunta and Foundal were able to pro¬duce in vitro Microtubers. The productivity of microtubers initiated from plantlets either infected with or free from PVX were evaluated. Elimination of PVX leads to great increase in total numbers, weight and diameter of microtub¬ers compared to those produced from infected cultures. Both size of microtubers and frequency of diameter equal to or larger than 5 mm were greatly improved by elimination of PVX . Results confirmed that potato plantlets as well as micro-tubers produced from virus-free tissue were remain unconta¬minated (virus-free) and vice versa. |
