Rooting of the Nursling Seedlings of Rice Exposed to Low Temperature and Wind after Transplanting

[摘要] The effect of wind and low temperature on the growth after transplantation of nursling seedlings of rice was examined. Three kinds of seedlings were raised under different conditions; (1)raised in the dark for 3 days after emergence, (2)raised under natural day light for 3 days after emergence, and (3)raised under natural day light for 5 days after emergence including a 2-day hardening. The seedlings were grown in temperature-controlled greenhouse with 24 / 19°C and 17 / 12°C day / night cycle after trasplanting. Elongation growth of the seedlings was poor under 17 / 12°C condition especially in the seedlings night cycle after transplanting. Elongation growth of the seedlings was poor under 17 / 12°C condition especially in the seedlings raised in the dark. When the seedlings reaised in the dark ware exposed to wind and low temperature, leaf elongation was severely inhibited. It was considered that the growth of the seedlings raised in thedark depended on the energy from the endosperm reserves under low temperature conditions even though at the 7th day after transplanting. This may be due to the inhibition of leaf elongation and chlorophyll formation by low temperature. On the other hand, the growth of the roots of the seedlings raised in the dark was similar or slightly inferior to that of the seedlings raised under natural day light. However, the degree of the suppression of root growth by wind and low temperature was similar in all kinds of seedlings.

[学科分类] 农业科学（综合）

[关键词] Growth;イネ;Leaf elongation;風;Low temperature;活着;Nursling seedling;生長;Rice;æ–­æ ¹;Rooting;低温;Root pruning;乳苗;Wind;葉伸長