Production and performance of potato mini-tubers

Abstract

Production of mini-tubers as a source for seed potato was investigated by growing in soil micropropagated plants and micro-tubers produced from micropropagated plants . Cultures of several cultivars were initiated from indexed tubers and multiplied on modified MS medium . Cultures were micropropagated by using a modular system which allowed batch handling . Micropropagated plants produced mini-tubers in glasshouse after 70-115 days of growth in soil . A large proportion of the mini-tubers produced were between 9 and 15 mm diameter . Several factors, e.g ., explant number, duration of in vitro culture and genotype influenced mini-tubers production . Micropropagated plants after culture of 86 days or longer produced micro-tubers ca . 2 to 10 mm diameter. Plants, which formed micro-tubers in vitro, produced less number of mini-tubers in soil . Micro-tubers produced 1 to 3 mini-tubers when grown in soil in chain-type paper pots, but produced conventional sized tubers when grown in soil under plastic polytunnel . Mini-tuber number varied widely between potato cultivars ; cvs. Bintje and British Queen produced more mini-tubers than the other cultivars . Mini-tubers developed green hard skins when kept in light for 3 weeks, and could be stored in dark at 4° C upto 6 months . In a field trial, small mini-tubers ca . 5-10 mm diameter produced more but smaller tubers than mini-tubers ca . 15-20 mm diameter. The micropropagated plants and the plants grown from mini-tubers were genetically stable, and did not show any morphological aberrations except for one variegated plant among the several thousand produced . It is concluded that the production of mini-tubers by soil planting of micropropagated plants is a rapid and efficient method for producing seed potato tubers .

Production of min-seed tubers using a modular system of plant micropropagation

“…Moreover, the 10 mm diameter mini-tubers produced a large number of small sized tubers between 25-34 mm than from 22 mm diameter (Table 4). This confirms the previous report that mini-tubers have tendency to produce many more small-sized tubers than the large mini-tubers or conventional tubers (Ahloowalia, 1994c). …”

“…Cultivars differ widely in their capacity to produce mini-tubers, some being much more prolific than others. Bintje produces an exceptionally high number of mini-tubers, 46 per pot (Ahloowalia, 1994c). Minitubers, 13 to 16 per pot, were obtained in British Queen, Red Pontiac, D6sir6e, Cara and Home Guard in which micropropagated plants were cultured for 6 to 9 weeks, and grown in soil for 12 to 13 weeks.…”

“…Claimer: Watson Module TM system used for mini-tuber production is a patented system (Ahloowalia, 1994c) but is available for use on a cost-free basis to all the Developing Member States of the United Nations (Ahloowalia, 1995) Disclaimer: The mention of any company, product, trade mark, patent or equipment does not constitute a formal approval or recommendation by the author or by the International Atomic Energy Agency or any agency of the United Nations.…”

“…In the system described below, in vitro produced microplants are grown in soil and produce small tubers of 5 to 25 mm diameter, referred to as mini-tubers (Ahloowalia, 1994c). The system of micropropagation is based on the use of pre-sterilized, disposable plastic containers which allows batch handling of micropropagules at all stages of in vitro culture and ex-vitro growth.…”

In-vitro Techniques and Mutagenesis for the Improvement of Vegetatively Propagated Plants

“…This system can be used both for the rapid multiplication and mutagenesis of vegetatively propagated plants; for example, the subculture of irradiated microplants to form micro-tubers and their subsequent soil planting has been used for obtaining several desirable mutants in potato cultivars (Ahloowalia, 1990). The system allows production of potato mini-tubers as a source of seed in large numbers (Ahloowalia, 1994). Similarly, explants of chrysanthemum and carnation were irradiated and multiplied using this system to obtain new floral types.…”