DEVELOPMENT AND ROOTING CAPACITY OF RICE NURSLING SEEDLINGS GROWN UNDER DIFFERENT RAISING CONDITIONS

To reduce the raising period of rice nursling seedling and to obtain e nough plant length (7 cm) for mechanical transplanting, nursling seedl ings were raised under different light conditions and for different ra ising periods. The length of nursling seedlings which was raised in th e dark (yellow nursling seedlings; YNS) for 7 days was 9.6 cm long. Wh ile that raised in the natural light (green nursling seedlings; GNS) f or 2 days at 25 degrees C and then placed in a vinil house for 3 days was 5.5 cm long. The length of YNS raised for 4 days was 4.1 cm, which is not the adequate size required for mechanical transplanting. The d ifferences between root numbers as well as that between the longest ro ot length of YNS and GNS at 5 and 10 days after transplanting were not significant. The amount of dry weight increase of YNS until 10 days a fter transplanting was lower than that of GNS. There was high correlat ion (r = 0.984) between the increase of dry weight and consumption of endosperm nutrient for all kinds of seedlings. In all treatments, a h igh correlation (r = 0.994*) was also observed between the increase o f total dry weight and consumption of endosperm nutrient until 5 days after transplanting. The growth and development of seedlings at this i nterval depended on the nutrient in the endosperm. Based on these resu lts, yellow nursling seedling might have been used as rice seedling.