剪根对杂交稻苗期生长及生理特性的影响

Effects of Root Pruning on Physiological Characteristics and Growth of Hybrid Rice Seedlings

以杂交稻F优498和德香4103为材料,砂培育秧35 d后,设置4种不同程度的剪根处理[分别将整株根系剪去1/3、剪去2/3、全部剪除、不剪根（对照）],研究剪根对杂交稻苗期生理特性及养分吸收和植株生长的影响。结果表明,剪根后0~24 h,各剪根处理的秧苗丙二醛含量、可溶性糖含量、脯氨酸含量均呈先升高后降低的变化趋势,且其含量均高于不剪根的对照;剪根程度越大,各生理指标的峰值越大,达到峰值的时间越短。剪根后1~14 d,各剪根处理的根长、根表面积、地上和地下部分干物质重、植株含氮量和氮积累量均不同程度低于对照,且随剪根程度的增大呈下降趋势。不同水稻品种受剪根影响的程度不同,F优498受剪根伤害的影响小于德香4103。

Two hybrid rice varieties（ F You 948 and Dexiang 4103） were used as the materials to study the effects of root pruning on the physiological characteristics,nutrient intake and growth of hybrid rice seedlings raised on sand medium for 35 days with four root pruning treatments,i. e.,whole root pruning（ A1）,2 /3 root pruning（ A2）,1 /3 root pruning（ A3） and no root pruning（ CK）. The results showed that,within 24 hours after root pruning,all treatments with root pruning had a rise at first but a reduction later in the contents of MDA,soluble sugar and proline（ Pro）; the contents of MDA,soluble sugar and Pro were all greater than those of the control with no root pruning; and the more roots were pruned,the earlier the peak of these physiological traits reached and the greater the peak values were. Within 1 ~ 14 days after root pruning,all treatments with root pruning decreased to some extent in root length,root surface area,shoot and root dry matter accumulation,plant nitrogen content and nitrogen accumulation with a greater degree for heavier pruning. Different rice varieties were affected by root pruning to a different extent. It is found that F You 498 was superior to Dexiang 4103 after root pruning in this study.