直根系

这一研究成果打破了长期以来认为苏铁类植物为直根系植物的结论，是苏铁类植物研究的一个新的、重大的发现。

This finding is contrary to the conclusion that Cycads belong to taproot system for a long time , and is a new discovery in Cycads research .

采用解剖学的方法对分布于广西的9种野生苏铁和1种栽培苏铁植物的根系类型及肉质根的结构进行解剖研究，结果表明：（1）苏铁属植物的根系属须根系而不是直根系。

The method of anatomy is used to study the root system and fleshy root structure of 9 species of wild Cycas and 1 species of cultivated Cycas in Guangxi . The results show that : ( 1 ) Cycas belong to fibrous root system but not taproot system .

经过对比研究发现，单子叶植物根际对PAHs的降解效率更高，直根系植物其根际降解作用能力较低。

The efficiency of PAHs degradation in monocot rhizosphere was higher than that in dicotyledon rhizosphere . The ability of rhizosphere PAHs degradation was low in straight-root plants .

脂肪含量相近时，表面粗糙或具有细密绒毛的叶片富集PAHs的能力较强，须根系根吸收PAHs的能力强于直根系根。

With close lipid concentrations , leaves with pubescence or rough surface were found to have stronger capability in uptaking PAHs than the others , and the capability of the fibre was stronger than the taproot .

以胡萝卜直根系为材料，分别研究了不同培养基、不同外植体及培养条件对愈伤组织诱导的影响，以及培养基对愈伤组织分化的影响。

The effects of different media , explant , culture condition on callus induction and media on regeneration of carrot main root were studied .

花生的根系是典型的直根系，按照定根的生长规律进行生长与分根。

The root system of peanut was a typical straight root system ; the growth and branching of root system followed the rule of fixed root .