In Vitro Corm Formation and Growth Habit of Propagated Seed Corm in Taro (Colocasia esculenta Schott.)
1992 Volume 61 Issue 1 Pages 55-61
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1992 Volume 61 Issue 1 Pages 55-61
Factors favorable for in vitro corm formation in 'Ishikawa-wase', an early maturing taro (Colocasia esculenta Schott.) cultivar and the subsequent growth of propagated seed corm were investigated. The morphology of plants grown from seed corms derived by 4 cultural treat-ments, their yield of cormels, and cormel size, shape, and weight were also studied to clar-ify growth factors.
1. Plantlets transplanted to MS liquid medium containing 8% sucrose and held at 25°C under light intensity of 30 μmol•m-2•sec-1 for 16 hr formed corms of about 1 g and 10 mm in diameter after 40 days.
2. Corms produced in vitro served as seed corms without any acclimation process. The use of in vitro propagated corms may be useful for mass propagation of virus-free seed plants as compared with the current method.
3. Top growth and corm size were less in plants grown from in vitro propagated seed corms weighing 1 g (IP plants) than plants grown from standard seed corm weighing 60 g (ST plants). Cormel yield of IP plants was nearly equal to that of ST plants. Hence, the fresh weight ratios of a) cormel to whole plant and b) cormel to corm + cormel of IP plants were greater than those of ST plants. The size and shape of cormels in IP plants were more uni-form than those of ST plants.
4. Top growth of IP plants was less than that of ST plants and that of plants grown from corms weighing 1.6 g that were obtained by withholding irrigation after the 6th leaf stage of IP plants (DT plants). The initial size of the seed corm affected the final harvest weight of the main corm and the number of cormels produced there from.
5. DT plants showed a similar growth pattern to plants grown from small ST corms weigh-ing 2 g (SST plants).
6. Top growth and cormel shape of IP plants were clearly different from those of plants derived from DT, SST, and ST plants. These results reveal that tissue culture techniques affected the subsequent growth habit of IP plants and that the IP corm could serve as seed corms without acclimation.
