土壤微生物区系破坏的原因：大田粮食作物由过量化学氮肥导致土壤酸化和土壤结构 破坏，而使土壤微生物区系破坏；经济作物由于长期连作、植物化感物质和过量化学 氮肥等原因，同样导致土壤微生物区系破坏 Cause: for grain crop soils, over application of chemical N fertilizers that cause significant decrease of pH, and thus destroyed soil microbial population; for cash crop soil, continuous monoculture where over application of chemical N fertilizers and allopathic substance prevail, which cause destroyed soil microbial population.
SQR9 ΔDegQ
WT SQR9
SSQQRR99
SQR9
(p(pUUBBCC1199:-ddeeggQQ)) (pUBC19: degQSU)
DegS-P DegQ DegU-P
Biofilm formation of SQR9 was significantly
affected by the phosphoraylation level of DegU
SQR9+degSU +degQ
DegS-P DegQ DegU-P
Relative expression of yqxM gene (log10 RQ)
Transcription of biofilm-related gene (yqxM) was regulated by DegU-P
1.4 1.3 1.2 1.1
Deletion of the global regulator (AbrB) enhanced the chemotaxis toward cucumber root exudates of SQR9
Finally, deletion of the global regulator (AbrB) enhanced the cucumber root colonization of SQR9 by CLMS
mutant
developed
biofilm as
wild type
strain
24h
Addition of purified Bacillomyci n D restored biofilm formation
log10 RQ(Relative quantification)
1.6 1.4 1.2
ΔDegQ
WT SQR9
SQR9
SQR9
(pUBC19: degQ) (pUBC19: degQSU)
12h
DegS-P DegQ DegU-P
ΔDegQ
WT SQR9
SQR9 (pUBC19: degQ)
SQR9 (pUBC19: degQSU)
24h
DegS-P DegQ DegU-P
Relative expression of yvcA gene (log10 RQ)
D mutant+ Bacillomycin D)
Wild type
yqxM
kinC
epsD
文章被AEM编辑推荐为当期Spotlight article, “An antibiotic that acts as both a weapon and a signal for a beneficial rhizosphere bacterium” 一种抗生素能同时作 为杀菌武器和有益菌根际定植的信号物质 。
Transcription of biofilm-related gene (yvcA) was regulated by DegU-P
1.6 1.4 1.2
1 0.8 0.6 0.4 0.2
0 -0.2 -0.4 -0.6 -0.8
-1 -1.2 -1.4 -1.6
ΔdegQ
WT
SQR9+degQ
(1) 芽孢杆菌生物膜形成的分子作用模型 Molecular acting model for biofilm formation in bacillus
Environmental signals
Quorum sensor
√
Environmental signals
(2) 解淀粉芽孢杆菌SQR9的全基因组 Genome of Bacillus amyloliquefaciens SQR 9
1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1
0 -0.1 -0.2
ΔdegQ
SQR9+degQ
WT
SQR9+degSU+degQ
DegS-P DegQ DegU-P
11.5 土壤微生物区系特征与调控 Characteristics of soil microbial population and management
(Water)
Bacillomycin D minus-mutant biofilm formation capacity is sharply decreased
Bacillomy
cin D
minus-
wild
Hale Waihona Puke mutant cannot
develop
biofilm
Fengycin
minus-
12h
(1) 农田土壤土壤微生物区系特征与调控 Characteristics of microbial population and management of grain cropping soil
细菌多样性第一 细菌多样性第二 细菌多样性第三 细菌多样性第四 细菌多样性第五 细菌多样性第六 细菌多样性第七 细菌多样性第八 细菌多样性第九
11.3 高附加值有机（类）肥料 High value-added organic-based fertilizers
11. 4 根际有益微生物（PGPR, SQR9）与根表形成生物膜相关的遗 传改良 Genetic improvements related to biofilm formation of PGPR, SQR9 on roots
不同施肥处理土壤的酶活性比较
Relative Taxonomic Abundance at Phylum Level
(2) 大棚黄瓜土壤土壤微生物区系特征与调控 Characteristics of microbial population and management of cucumber planting soil
有机肥
生物肥
通过功能性微生物有机肥调控后健康土壤与导病型土壤微生物区系的比较 Comparison of soil microbial populations and structure in the two treatments, which implies that organic fertilizers rather than bio-organic fertilizers can not improve the soil microbial population if the soil is diseased.
(5) DegU is a global regulator and its different levels of phosphoraylation controls different genes in Bacillus strains
Different mutant strains of SQR9 with different level of DegU-P
11.5 土壤微生物区系特征与调控 Characteristics of soil microbial population and management
11. 4 根际有益微生物（PGPR, SQR9） 与根表形成生物膜相关性状的遗传改良 Genetic improvements related to biofilm formation of PGPR, SQR9 on roots
目 录 Content
11.1 发展有机肥料的意义 Significance of organic fertilizer development
11.2 堆肥(商品有机肥生产)工艺与技术 Technology of composting (to produce commercial organic fertilizers)
Only Bacillomycin D showed strong activity against pathogen Fusarium oxysporum , Fengycin showed weak antagonistic activity.
Bacillomycin D mutant lost the antagonistic activity against Fusarium oxysporum 1. WT 2. SQR9M1 (Bacillomycin D mutant) 3. Water control 4. SQR9M2 (Fengycin mutant)
“ 土壤微生物区系被破坏”成为中国土壤肥力 的新的“木桶短板”。 Destroyed soil microbial population and structure has been or is becoming a new limiting factor in crop production in China.
SQR9