不同品种小麦与蚕豆间作对蚕豆枯萎病发生、根系分泌物和根际微生物群落功能多样性的影响

通过田间小区试验和盆栽试验，研究了3个不同品种小麦［云麦42（YM42），云麦47（YM47）和绵阳29（MY29）］与蚕豆间作对蚕豆枯萎病发生、 根系分泌物和根际微生物群落功能多样性的影响。结果表明，云麦42与蚕豆间作处理（YM42//B）和云麦47与蚕豆间作处理（YM47//B）使蚕豆枯萎病病情指数分别降低47.6%和33.3%，而绵阳29与蚕豆间作处理（MY29//B）对蚕豆枯萎病病情指数无显著影响。与蚕豆单作相比，YM42//B和YM47//B处理显著增加了根系分泌物中有机酸的含量，显著降低了根系分泌物中可溶性总糖和游离氨基酸含量; 显著提高了蚕豆根际微生物对碳源的利用强度，明显改变了蚕豆根际微生物群落结构，并且YM42//B处理的影响大于YM47//B; 而MY29//B处理对碳源利用强度、 根际微生物群落结构和根系分泌物中有机酸、 可溶性总糖和游离氨基酸含量均无显著影响。 YM42//B处理根际微生物利用碳源的种类比YM47//B处理多，同时YM42//B和YM47//B处理利用的糖类、 氨基酸类和羧酸类碳源种类完全不同。表明云麦42和云麦47与蚕豆间作通过增加有机酸含量，从而提高根际微生物活性和多样性，促进了根际微生物利用更多的碳源，同时云麦42和云麦47与蚕豆间作抑制了氨基酸和总糖的分泌，而最终控制了蚕豆枯萎病的发生。表明不同品种小麦与蚕豆间作系统根系分泌物-根际微生物的互作是影响蚕豆枯萎病抗性的重要原因。小麦与蚕豆间作控病效果受小麦品种的影响，以云麦42与蚕豆间作效果最好，其次为云麦47与蚕豆间作，而绵阳29与蚕豆间作无显著控病效果。

Effects of different wheat cultivars intercropped with faba bean on faba bean Fusarium wilt,root exudates and rhizosphere microbial community functional diversity

Field and pot experiments were conducted to examine effects of three different wheat cultivars［Yunmai 42（YM42），Yunmai 47（YM47） and Mianyang 29（MY29)］and faba bean intercropping on occurrence of faba bean Fusarium wilt,  root exudates content and rhizosphere microbial community functional diversity. Results show that compared with the faba bean monocropping,  the disease index of faba bean Fusarium wilt is significantly decreased by 47.6%in the yunmai 42 intercropped with faba bean system (YM42//B) and decreased by 33.3% in the yunmai 47 intercropped with faba bean system (YM47//B),  while the disease index of faba bean Fusarium wilt is not significantly changed in the mianyang 29 intercropped with faba bean system (MY29//B). Compared with the faba bean monocropping,  the YM42//B and YM47//B treatments significantly increase the total content of organic acids and significantly reduce the total content of soluble sugars and free amino acids in the root exudates. The total utilization ability of carbon sources is significantly increased and the microbial community structures of faba bean rhizosphere are altered under the YM42//B and YM47//B treatments,  and the YM42//B treatment has more obvious effect than the YM47//B treatment. The MY29//B treatment has no significant effects on substrate utilization,  total content of soluble sugars,  free amino acids and organic acids in the root exudates and microbial community structures. The rhizosphere microbe of the YM42//B treatment could use more types of carbon source than the YM47//B treatment,  and the carbon source types of sugars,  amino acids and carboxylic acids used by rhizosphere microbe of the YM42//B treatment are quite different from the YM47//B treatment. The total content of organic acids in the root exudates is increased under YM42 and YM47 intercropped with faba bean,  thus the rhizosphere microbial activity and diversity are improved,  and more carbon sources are utilized by rhizosphere microorganisms. Meanwhile secretion of soluble sugar and  free amino acid is inhibited by the YM42//B and YM47//B treatments. Our result illustrates that the interaction of root exudates and rhizosphere microbes is the main reason of affecting faba bean Fusarium wilt control. Effects of the intercropping on diseases control are influenced by wheat cultivars,  and the YM42//B is the best,  the YM47//B shows the medium effect and the MY29//B has no significant disease control effect.