Skip to main content

Taiwan Agricultural Research Institute, Council of Agriculture, Executive Yuan(back to Home)

Taiwan Agricultural Research Institute, Council of Agriculture, Executive Yuan--Achievements-Innovative techniques

Innovative techniques

print  |
Prevention of Growth Retardation and Adjustment of the Production Period of Manchurian Wild Rice (‘Jiaobai’)
A field of Manchurian wild rice in the winter (A). Note stunting growth of plants (A, B) with formation of small stem base galls (D, right), whereas plants with normal growth are tall (C) with large edible stem base galls or Jiaobai Shun (D, left).
A field of Manchurian wild rice in the winter (A). Note stunting growth of plants (A, B) with formation of small stem base galls (D, right), whereas plants with normal growth are tall (C) with large edible stem base galls or Jiaobai Shun (D, left).
Plants of Manchurian wild rice grown under short day length (<14 hr/day) (left) and under extended lighting conditions (>14 hr/day) (right). Note the difference in plant height between the treatments.
Plants of Manchurian wild rice grown under short day length (<14 hr/day) (left) and under extended lighting conditions (>14 hr/day) (right). Note the difference in plant height between the treatments.

    Manchurian wild rice (Zizania latifolia) or ‘Jiao-Bai’ is grown in shallow water. It is an important vegetable crop produced mainly in Nantou county, Taiwan. Infection of stem base of wild rice plants by the smut fungus (Ustilago esculenta) resulted in formation of swollen basal stems called a gall or ‘Jiaobai Shun’ which are harvested and used as vegetable. Traditionally, the Manchurian wild rice was planted in January and the swollen basal stems or Jiaobai Shun were harvested in April. However, Manchurian wild rice planted earlier than January resulted in poor yields of Jiaobai Shun due to poor growth, stunting of plants and high incidence of abnormal galls or of no commercial value. Studies at TARI showed that extending the light period to over 14 hr/day with the aid of artificial illumination not only prevented growth retardation of plants but also caused wild rice plants to produce edible Jiaobai Shun 30 days earlier than the conventional cultural practices without the illumination treatment. This lighting treatment technique is now widely used for the commercial production of stem base galls or Jiaobai Shun from plants of Manchurian wild rice in Taiwan.

Night lighting in a field of Manchurian wild rice to extend the winter lighting period (>14 hr/day) (A) for maintaining normal plant growth (B) and producing large edible stem basal stem galls or Jiaobai Shun of high commercial value.
Night lighting in a field of Manchurian wild rice to extend the winter lighting period (>14 hr/day) (A) for maintaining normal plant growth (B) and producing large edible stem basal stem galls or Jiaobai Shun of high commercial value.