低温下土壤水分对籼稻及粳稻根系生长的影响

Effects of the Soil Moisture at Low Temperature on the Growth of Roots

用籼稻品种浙 92 48,湘早籼 2 4号和粳稻品种胆振早稻 ,早雪 ,探讨低温及不同土壤水分条件下水稻根系生长及与根系活性变化的关系 .结果如下 :低温下籼稻品种湿润处理的增加根数、种子根伸长量、种子根的一次侧根、粗大一次分枝根增加数以及根系伤流量优于淹水区 ,并且籼稻品种少于粳稻品种 ,根系生理活性的大小与根的生长量具有密切关系 .恢复常温后的增加根数、剪根移栽后的发根数、伤流量的恢复程度也以湿润处理的为优 ,这与低温时根的生长及伤流量的变化有密切的对应关系 .认为在根的生长界限温度条件下 ,由于湿润处理增加了分枝根的数量 ,特别是粗大分枝根的数量 ,提高了根的生理活性维持能力 ,这与低温处理后生长恢复的优势密切相关 .

This paper is a probe into the effect of soil moisture content at a low temperature on the growth of roots with indica varieties Zhe 9248, Xiangzaoxian24 and japonica varieties Tanshinwase,hayayuki. The result was as follows: After the exposure to a low temperature(11 ℃), the number of roots, the length of seminal root,the number of lateral roots and the bleeding rate were higher in the wet soil plots(WP) than in flooded soil plots(FP). These tendencies were remarkable in indica varieties. The superior growth of the seminal root and development of the lateral roots might be responsible for the superior root activities. After the seedlings returned to the normal temperature, the recovery of the root number,the bleeding rate and the rooting ability was higher in WP.Based on these results, it is considered that the higher recovery of root growth and activities of the root in WP compared to FP after returned to the normal temperature might be due to the less damage to root growth and activity in WP during the low temperature exposure.