Interaction between photoperiod and seed tuber weight on the development of the main shoot, spikes, and new tubers in Chinese yam (Dioscorea opposita Thunb. cv. Ichoimo), plants were investigated. Growth of the main shoot was promoted by a 24-hr photoperiod (continuous light) in combination with a large seed tuber weight, but inhibited by an 8-hr photoperiod in combination with a small seed tuber weight. Cessation of shoot elongation was advanced by the short photoperiod in combination with light seed tubers. Flowering spikes were initiated on plants with seed tuber weighing 25 g or more under both 8- and 24-hr photoperiods. The proportion of plants developing spikes increased with tubers weighing in excess of 25 g. The node positon of the first spike was shorter under the 8-hr photoperiod than that under the 24-hr photoperiod. The date of flower bud emergence under the 8-hr photoperiod was earlier than that in the 24-hr photoperiod. The large tubers produced more spikes under a 24-hr photoperiod than with an 8-hr photoperiod. Early development of aerial and new tubers was promoted by an 8-hr photoperiod when the tubers weighed between 10 and 50 g, but they were inhibited under both 8- and 24-hr photoperiods if the tuber weighed 100g. The large final fresh weights of aerial and new tubers under the 24-hr photoperiod is attributed to the extensive shoot growth. However, dry weight ratios of total tubers to leaves were high in plants derived from small seed tubers under 8- and 24-hr photoperiods. These results indicate that the early development of aerial and new tubers is promoted by a small seed tuber weight.
|Number of pages||5|
|Journal||Journal of the Japanese Society for Horticultural Science|
|Publication status||Published - 2000 Jul|
- Dioscorea opposita
- Seed tuber weight
ASJC Scopus subject areas