铁棒锤根系生长动态研究

Growth dynamics of root system of Aconitum pendulum Busch

采取田间抽样调查的方法,对铁棒锤根系的生长动态进行了研究.结果表明,生长150 d左右子根开始形成,240 d左右子根个数达到最大,270 d左右生长量达到最大（干质量11.47 g/株）;在整个生长周期内,母根生长量逐渐减小,生长的后期伴随新母根的形成原母根消失;根系含水量在生长的前期较高（70%～80%）,后期较低（62%）;根系体积和生长量的变化趋势一致.据此认为,生长210～240 d（6月25日～7月25日）是水肥管理的关键时期.生长270 d（8月25日）为最佳采收期.铁棒锤根系统中全根鲜质量、子根鲜质量、全根干质量、子根干质量、根系体积、子根体积均能建立良好的生长曲线,且相关系数（r≥0.934 5）均达到极显著水平,确定系数高于0.976 5.

Based on the field and lab tests,the growth dynamics of root system of Aconitum pendulum Busch were studied in order to provide the theoretic basis for optimal harvesting. The results showed that the daughter roots initially formed after the root tuber had been grown for about 150 days. The daughter roots reached its highest number after about 240 days and its highest growth amount （11.47 g dry weight per plant） after 270 days. However,the growth amount of the mother roots gradually reduced in the whole growth period. At the end of growth, the primary mother roots vanished after the young mother roots formed. The water content of root system was higher （70 %-80 %）in the early growth stage than that in the late growth stage （62 %）. The change trends of the cubage of roots was consistent with that of the growth amount of roots. All the results above indicated that the growth period from 25th June to 25th July was regarded as the key stage in water and fertilizer management of Aconitum pendulum ,and the optimal harvesting date of the roots was determined as after 270 days （25th August）. The good growth curves of fresh weight, dry weight and cubage of the whole roots and the daugther roots could be established （r≥0. 934 5,P〈0.01 ;R^2≥0. 976 5,P〈0.01）.