中文摘要：

通过对丹参红叶病株与健康株根区土养分含量及根区土和根表土中的微生物区系比较，探索丹参红叶病发生的微生态机制．结果表明：丹参红叶病株叶片中N、P、K、Mn含量均显著低于健康株（P〈0．05）；根区土中速效P与健康株根区土无显著差异，速效N、K含量均显著高于健康株根区土（P〈0．05），表明丹参红叶病害发生与P缺乏有关，但植株缺磷不是由于土壤供磷不足所致．丹参红叶病株根区土细菌数量较健康株减少41．3％，真菌和放线菌数量分别较健康株增加156．6％和189．5％，差异均达显著水平（P〈0．05）；丹参红叶病株根表土细菌、真菌和放线菌数量变化趋势与根区土一致．在丹参红叶病株根区、根表土壤中，6种优势真菌、4种优势放线菌及2种优势细菌可能为有害微生物．优势真菌为腐皮镰刀菌、露湿漆斑菌、三线镰刀菌、焦曲霉、尖孢镰刀菌及座囊菌；优势放线菌为砖红链霉菌、威威达湖伦茨氏菌、马铃薯疮痂病原链霉菌及山丘链霉菌；优势细菌为阿氏芽孢杆菌及水生细菌．这些优势微生物可能通过影响根系生长及根系对土壤养分吸收引起丹参出现缺磷现象．表明丹参红叶病的发生与丹参根区土和根表土中微生物区系异常密切相关．

英文摘要：

A comparative study was made on the nutrient content in rhizosphere soil and the micro- flora in rhizosphere soil and on rhizoplane of healthy and red-leaf diseased Salvia miltiorrhiza plants, aimed to approach the microeeologieal mechanisms of red-leaf disease occurrence in S. miltiorrhiza. The N, P, K, and Mn contents in the diseased plant leaves were significantly lower than those in the healthy plant leaves （P〈0.05）. No significant difference was observed in the available P content in the rhizosphere soils of diseased and healthy S. miltiorrhiza, but the available N and K contents were significantly higher （ P 〈 0.05 ） in the rhizosphere soil of diseased S. miltiorrhiza. These results indicated that the red-leaf disease occurrence in S. miltiorrhiza was related to plant P deficiency, but the lack of P in the plants was not caused by the insufficient soil P supply. As compared with those in healthy S. miltiorrhiza rhizosphere, the bacterial number in diseased S. miltiorrhiza rhizosphere soil decreased by 41.3% , while the fungal and actinomycetes numbers increased by 156.6% and 189.5% （P〈0. 05）, respectively. Similar variations in the numbers of bacteria, fungi, and actinomycetes were observed on diseased S. miltiorrhiza rhizoplane. In the rhizosphere soil and on the rhizoplane of diseased S. miltiorrhiza, the predominant microbial species that might be harmful included six fungi （Fusarium solani, Myrothecium roridum, F. tricinctum, Aspergillus calidoustus, F. oxysporum, and Dothideomycetes sp. ） , four aetinomycetes （Streptomyces lateritius, Lentzea waywayandensis, S. stelliscabiei and S. collinus ） , and two bacteria （Bacillus aryabhattai and Piscinibacter aquaticus）. These predominant soil microbes likely caused plant P deficiency via negatively affecting the growth of roots and their absorption of soil nutrients. It was suggested that the red-leaf disease occurrence in S. miltiorrhiza was closely related to the plant P deficiency caused by the abnormality of soil microflora in