CAJ | 학술논문

为探索外来入侵植物假高粱（Sorghum halepense (L.) Pers）根系分泌物对入侵地土壤细菌群落的影响，在室内采用盆栽模拟试验进行了研究。为消除假高粱根系分泌物对土壤的微生物的影响，实验中分别设计添加活性炭的组以及未添加活性炭的组分别培养。应用PCR-DGGE技术，通过细菌16S rDNA V3区片段的变形梯度凝胶电泳（DGGE）来研究土壤细菌群落结构的影响。研究结果表明：添加活性炭的假高粱根系土壤微生物多样性水平显著低于没有活性炭影响的组，在生长160 d时，其Shannon指数分别是2.54和3.24，表明假高粱根系分泌物可以显著提高土壤微生物多样性水平和丰富度。在假高粱不同生长时期，土壤微生物群落结构呈现出差异，其抽穗开花期后土壤细菌群落结构发生较大变化，与对照组的相似性指数仅为50%左右。这可能是因为随着假高粱的生长，根系分泌物的种类和释放量均有所增加，从而对土壤微生物的影响也较大。对 DGGE 图谱差异条带分析结果显示，假高粱根系分泌物对部分细菌类群有显著促进作用，而对部分细菌类群则显示抑制作用，这表明假高粱根系分泌物对土壤微生物种群的影响具有选择性。由此我们认为，假高粱可能通过根系分泌物影响入侵地的土壤微生物群落结构和多样性，并且随着假高粱生长，影响越来越显著，这可能成为假高粱成功入侵的重要原因之一，该研究为进一步研究明确假高粱对土壤微生物的影响奠定了基础。
위탐색외래입침식물가고량（Sorghum halepense (L.) Pers）근계분비물대입침지토양세균군락적영향，재실내채용분재모의시험진행료연구。위소제가고량근계분비물대토양적미생물적영향，실험중분별설계첨가활성탄적조이급미첨가활성탄적조분별배양。응용PCR-DGGE기술，통과세균16S rDNA V3구편단적변형제도응효전영（DGGE）래연구토양세균군락결구적영향。연구결과표명：첨가활성탄적가고량근계토양미생물다양성수평현저저우몰유활성탄영향적조，재생장160 d시，기Shannon지수분별시2.54화3.24，표명가고량근계분비물가이현저제고토양미생물다양성수평화봉부도。재가고량불동생장시기，토양미생물군락결구정현출차이，기추수개화기후토양세균군락결구발생교대변화，여대조조적상사성지수부위50%좌우。저가능시인위수착가고량적생장，근계분비물적충류화석방량균유소증가，종이대토양미생물적영향야교대。대 DGGE 도보차이조대분석결과현시，가고량근계분비물대부분세균류군유현저촉진작용，이대부분세균류군칙현시억제작용，저표명가고량근계분비물대토양미생물충군적영향구유선택성。유차아문인위，가고량가능통과근계분비물영향입침지적토양미생물군락결구화다양성，병차수착가고량생장，영향월래월현저，저가능성위가고량성공입침적중요원인지일，해연구위진일보연구명학가고량대토양미생물적영향전정료기출。
The aim of the present study is to investigate the effects of invasive plant Johnsongrass (Sorghum halepense (L.) Pers) root exudates on soil bacteria. In a greenhouse experiments, activated carbon was used to investigate root exudates of Johnsongrass because it adsorbs and thereby neutralizes root exudates. The experiment consisted of two combined soil treatments:with or without activated carbon. 16S-rDNA-V3-fragnent-base DGGE (denaturing gradient gel electrophoresis) was applied to explore variation of the soil bacterial structure. To calculate the diversity parameter, Shannon algorithm was used. The results showed that activated carbon led to a considerable decrease in the soil bacterial diversity level and abundance compared to the without activated carbon treatments. The Shannon diversity index is 2.54 and 3.24 separately in the 160 days. This indicates that Johnsongrass root exudates alter community structure and increase diversity of soil bacteria in rhizobacterial communities. It is different in the bacterial structure with the growth of the plant. The bacterial community showed a high difference with the 50%Jaccard's index of similarity in the florescence, suggesting that increases in root exudates support an increased soil bacterial population. DGGE analysis results show that Johnsongrass root exudates promoted some kinds of rhizobacterial, and show inhibition to some other kinds of the communities. This study establishes root exudates as a mechanism through which a plant is able to regulate soil bacterial community composition, and could be related to the invasive of exotic invasive plants and the soil microbes in rhizosphere.