Effect of In Vitro Calcium Fortification on Regeneration and Microtuberization of Three Selected Irish Potato Varieties

Potato is an important tuber crop that plays a key role in food security in sub-Saharan Africa. However, potato production faces challenges including limited clean seed and nutrient deficiencies of microplants. The availability of clean and viable seed is the most constraining challenge hence necessitating the development of new strategies for enhancing production. Understanding the link between in vitro nutrient enhancement and seedling vigor under field conditions may mitigate these challenges after microplant transplanting. In vitro experiments were set up to investigate the effect of calcium (Ca) fortification on potato varieties Shangi, Unica and Dutch Robjyn regeneration and microtuberization. Cuttings were subcultured onto modified MS media with five levels of Ca ۸.۸g/L, ۱۰.۴g/L, ۱۲g/L, ۱۳.۶g/L and ۱۵.۲g/L CaCl۲. Microtubers were initiated on media with ۶۰g/L brown sugar and ۶mg/L ۶-Benzylaminopurine. The experiment was set up in a completely randomized design replicated three times. The regeneration capacity of the tested varieties differed significantly, evidenced by shoot (p=۰.۰۰۰۲) and root number (p=<.۰۰۰۱). Response to fortification was variably dependent with ۱۰.۴-۱۳.۶g/L leading to a significant increase (p<۰.۰۵) in root number in the three varieties. ۱۳.۶g/L CaCl۲ led to an increase in root-zone and mid-stem Ca content by ۴۵%, ۲۰۲% and ۱۶۵% for Shangi, Unica and Dutch Robjyn respectively compared to the control. Dutch Robjyn and Shangi showed better regeneration and microtuberization in comparison to variety Unica under ۱۰.۴-۱۳.۶g/L CaCl۲. Results confirm the optimization of MS regeneration protocol by Ca enhancement as a potential technology for scaling up the production of clean quality seed.

کلیدواژه ها:

Micropropagation ، Calcium ، Clean seed ، potato ، Fortification ، Microtuberization