微生物有机肥对黄瓜枯萎病及土壤微生物区系的影响

发布时间：2019-01-07 20:29

【摘要】：黄瓜是全世界最重要的蔬菜作物之一,具有极其重要的经济价值。长期不科学的种植方式,如连作、滥用化肥等使黄瓜生产发生严重的连作障碍,其中,黄瓜枯萎病是造成黄瓜减产的最严重的连作障碍之一,且目前没有一种方法可以完全抑制枯萎病的发生。造成黄瓜枯萎病的原因主要是连作导致的土壤微生物区系恶化,土壤中有益菌数量减少,有害菌成为优势菌群等。黄瓜连作障碍的常用防治方法有化学防治,物理防治和生物防治等。其中,生物防治是目前公认最有前景的方法,对可持续农业的发展具有重要的意义。有研究表明,微生物有机肥料(BIO)中含有的活性物质和各类营养元素,可改善作物根系土壤微生态环境和土壤的理化性质。本文以黄瓜枯萎病的生物防治为研究基础,通过盆栽实验和定点实验进行了多方面的探索,得到以下结果:(1)盆栽实验研究了不同浓度BIO生物肥对黄瓜产量,枯萎病发病率以及土壤中致病菌和拮抗菌数量的影响。结果表明:与化肥对照(CK)相比,施用高浓度BIO生物肥能显著降低黄瓜枯萎病发病率,提高产量,增加土壤肥力,而施用低浓度的BIO生物肥并没有明显的改善。其中,BIO10和BIO20组的黄瓜产量约为CK、BI02.5和BI05组的5倍。荧光定量PCR测定黄瓜根际尖孢镰刀菌黄瓜专化型(F.oxysporum f.sp.cucumerinum)和拮抗菌(Bacillus amyloliquefaciens SQR9)相对数量的结果表明,随着BIO生物肥浓度的增加,土壤中F.oxysporum f.sp.cucumerinum的数量减少,SQR9的数量增加。(2)通过对盆栽实验的土壤进行Biolog分析,结果发现,与化肥对照(CK)相比,施用高浓度的BIO生物肥能显著增加土壤微生物的活性及其对31种碳源的整体利用率,而施用低浓度的BIO生物肥反而会使其降低。(3)通过对盆栽实验的土壤基因组提取物进行高通量测序分析,结果显示,与化肥对照(CK)相比,高浓度BIO生物肥的施用能显著增加土壤中Kaistobacter、生丝微菌属(Hyphomicrobium)、曲霉属(Aspergillus)等有益微生物的数量,同时会降低枝孢属(Cladosporium)、Monosporascus、茎点酶属(Phoma)等有害微生物的数量,而施用低浓度BIO生物肥的土壤中的微生物群落并没有明显的变化。(4)通过对常年黄瓜连作地区进行定点实验,结果发现,施用加有BIO生物肥的各处理的平均亩产量比不施肥对照(T1)和加有常规有机肥的处理分别增产23.11%和16.31%;且与其他各组相比,施用加有BIO生物肥的各处理的土壤肥力显著提高,黄瓜枯萎病发病率较低,均低于10%。(5)通过对常年定点实验地区的土壤进行根际微生物测定及对其土壤基因组提取物进行高通量测序分析,结果发现,与不施肥对照(T1)和其他各组相比,施用加有BIO生物肥的各处理的土壤中细菌和放线菌总数增加,且土壤中假单胞菌(Pseudomonas),根瘤菌(Rhizobia)等益生菌数量也显著增加。
[Abstract]:Cucumber is one of the most important vegetable crops in the world. Long-term unscientific planting methods, such as continuous cropping, misuse of chemical fertilizers, etc, cause serious continuous cropping obstacles in cucumber production. Among them, cucumber wilt is one of the most serious continuous cropping obstacles resulting in cucumber yield reduction. And there is no way to completely inhibit the occurrence of wilt. The main causes of cucumber wilt disease were the deterioration of soil microbial flora caused by continuous cropping, the decrease of beneficial bacteria in soil, and the predominance of harmful bacteria. The common control methods of cucumber continuous cropping obstacle include chemical control, physical control and biological control. Biological control is currently recognized as the most promising method, which is of great significance to the development of sustainable agriculture. Some studies have shown that the active substances and various nutrient elements contained in microbial organic fertilizer (BIO) can improve the microecological environment of crop root soil and the physical and chemical properties of soil. Based on the biological control of cucumber wilt, pot experiments and site-directed experiments were carried out in this paper. The following results were obtained: (1) pot experiments were conducted to study the effects of different concentrations of BIO bio-fertilizer on cucumber yield. The incidence of Fusarium wilt and the effect of pathogenic bacteria and antagonistic bacteria in soil. The results showed that the application of high concentration BIO bio-fertilizer could significantly reduce the incidence of cucumber wilt disease, increase yield and increase soil fertility, but the application of low concentration of BIO bio-fertilizer had no obvious improvement. The cucumber yield of BIO10 and BIO20 groups was about 5 times of that of CK,BI02.5 and BI05 groups. The relative quantities of F.oxysporum f.sp.cucumerinum and (Bacillus amyloliquefaciens SQR9 of Fusarium oxysporum in the rhizosphere of cucumber were determined by fluorescence quantitative PCR. The results showed that the concentration of BIO bio-fertilizer increased with the increase of BIO concentration. The amount of F.oxysporum f.sp.cucumerinum in soil decreased, and the amount of SQR9 increased. (2) through the Biolog analysis of pot experiment soil, the results showed that compared with chemical fertilizer control (CK), The application of high concentration BIO bio-fertilizer could significantly increase the soil microbial activity and the overall utilization rate of 31 carbon sources. However, the application of low concentration of BIO bio-fertilizer could reduce it. (3) by high-throughput sequencing analysis of soil genomic extracts from pot experiment, the results showed that compared with chemical fertilizer control (CK), The application of high concentration BIO bio-fertilizer could significantly increase the number of beneficial microbes such as Kaistobacter, (Hyphomicrobium), (Aspergillus), and decrease the number of harmful microbes such as (Cladosporium), Monosporascus, (Phoma) and so on. However, the microbial community in the soil with low concentration of BIO fertilizer did not change significantly. (4) the results showed that: (1) the microorganism community in the soil with low concentration of BIO fertilizer did not change significantly. (4) the results showed that: 1. The average yield increased by 23.11% and 16.31% in the treatments with BIO bio-fertilizer compared with the control without fertilization (T1) and the treatment with conventional organic fertilizer, respectively. Compared with other groups, the soil fertility of the treatments with BIO bio-fertilizer increased significantly, and the incidence of cucumber wilt was lower. (5) the rhizosphere microbes of the soils in the perennial site-directed experimental area and the high-throughput sequencing analysis of the genomic extracts from the soils were determined. The results showed that compared with the control group (T1) and other groups, The total number of bacteria and actinomycetes in the soil treated with BIO bio-fertilizer increased, and the number of probiotics such as (Pseudomonas), rhizobium (Rhizobia) in the soil increased significantly.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S436.421.13;S154.3

【相似文献】