本文選題：小麥條銹病 + 內(nèi)生細菌��； 參考：《廣西大學(xué)》2016年博士論文

【摘要】：小麥條銹病是由Puccinia striiformis west.f.sp.tritici Eriks et Henn引起的真菌性病害,也是世界上小麥最嚴重的病害之一。由于其發(fā)生區(qū)域廣,流行頻率高,危害損失重等特點已成為影響小麥穩(wěn)產(chǎn)高產(chǎn)的主要因素。目前對小麥條銹病的防治主要采用抗性品種、化學(xué)藥劑和農(nóng)業(yè)綜合防治措施。但由于小麥條銹病菌生理小種變異快及施用農(nóng)藥造成藥劑污染等原因,生產(chǎn)上迫切需要一種可持續(xù)、環(huán)保的方法來進行小麥條銹病的防治。內(nèi)生細菌因其特有的優(yōu)點及多樣的生物學(xué)特性,受到眾多植物病理學(xué)家的關(guān)注。但是用小麥內(nèi)生細菌防治小麥條銹病還鮮有報道。作者對小麥內(nèi)生細菌的種群多樣性進行了調(diào)查,從分離的內(nèi)生細菌中篩選出對小麥具有顯著促生、防病和增產(chǎn)效果的菌株,并對其防病促生和增產(chǎn)機理進行了研究,主要結(jié)果如下：1、本研究對采自不同地區(qū)、不同時期、不同器官的健康小麥樣品進行內(nèi)生細菌的分離并對其種群多樣性進行分析。結(jié)果表明：從小麥體內(nèi)共分離出內(nèi)生細菌313株,其中從南陽市臥龍區(qū)樣品中分離出的內(nèi)生細菌數(shù)為101株,占總細菌數(shù)的32.27%；不同小麥器官的內(nèi)生細菌數(shù)量存在差異,在整個生長期,根部內(nèi)生細菌的數(shù)量最多達11.5×105cfu/g,莖、葉片和籽粒中內(nèi)生細菌數(shù)量分別為688×105cfu/g、4.77×105cfu/g 和 3.47× 105 cfu/g;不同時期內(nèi)生細菌分離也存在差異,抽穗期內(nèi)生細菌數(shù)量為10.48×105cfu/g,分蘗期、拔節(jié)期和蠟熟期內(nèi)生細菌數(shù)量分別為2.73×105cfu/g、6.65×105cfu/g和9.3× 105cfu/g。經(jīng)過16S rDNA序列比對分析,內(nèi)生細菌群落共包含23 Operational taxonomic units (OTU),歸屬于9個屬。芽孢桿菌屬(Bacillus)為優(yōu)勢菌群,占細菌總數(shù)的76.37%,假單胞屬次之,占細菌總數(shù)的10.23%。蠟樣芽孢桿菌(B. cereus)和枯草芽孢桿菌(B.subtilis)在小麥整個生長過程中具有較高的分離頻率,分別為9.7%和4.37%。Stenotrophomonas maltophilia作為小麥內(nèi)生菌為首次報道。2、以127株小麥內(nèi)生細菌為研究對象,通過室內(nèi)和室外試驗就內(nèi)生細菌對小麥幼苗促生作用進行研究,采用聚類分析、判別分析和相關(guān)分析等綜合統(tǒng)計分析法,對實驗結(jié)果進行分析。結(jié)果表明：6株內(nèi)生細菌(SB127, LD161、RA135、JD204、 RC79、RB132)對小麥的生長指標(葉長、莖葉干重、根干重)、解無機磷與有機磷能力、產(chǎn)生長素量等8個觀察指標都較高,且生長指標與解磷能力及產(chǎn)生長素量有顯著的正相關(guān)性,內(nèi)生細菌的解磷能力及產(chǎn)生長素量對小麥生長有顯著的影響。不同的內(nèi)生細菌促進小麥生長的作用不同。選擇生長素分泌量高、解磷能力強的內(nèi)生細菌菌株,對促進小麥生長,防治小麥病害有積極意義。3、根據(jù)形態(tài)學(xué)、生理生化特征和16S rDNA序列同源性對6株內(nèi)生細菌(RC79、SB127、 RB132、 RA135、 LD16、 JD204)進行鑒定,并對2株(LD161、JD204)還用rpoD基因進行了鑒定,初步將其歸為蠟樣芽孢桿菌(Bacillus cereus)、巨大芽孢桿菌(Bacillus megaterium)、枯草芽孢桿菌(Bacillus subtilis)、熒光假單胞菌(Pseudomonas fluorescens)和惡臭假單胞菌(Pseudomonas putida)。 6株內(nèi)生細菌的最適生長溫度均為28℃～30℃,最適生長pH值均為6～8；菌株RC79、SB127、RB132 與 RA135均能有效利用葡萄糖碳源,菌株LD161與JD204可利用除木糖醇外的供試碳源,6株菌株幾乎能利用所有的供試8種氮源。除RB132外所有菌株均檢測到精氨酸脫羧酶與賴氨酸脫羧酶活性。定殖實驗表明：6株促生菌株均可穩(wěn)定在小麥體內(nèi)定殖,并且菌株SB127、RB132和JD204在小麥體內(nèi)可以向地上部轉(zhuǎn)移。4、內(nèi)生細菌對14個不同小麥品種的大田防效和增產(chǎn)試驗結(jié)果表明：用6株內(nèi)生細菌RC79M、SB127M、RB132M、RA135M、 LD161M和JD204M分別處理14個不同小麥品種后,小麥平均發(fā)病率為14.62%～19.9%,約為對照區(qū)平均發(fā)病率的68.9%～83.4%；內(nèi)生菌處理后病情指數(shù)平均為4.98～7.13,約為對照區(qū)平均病情指數(shù)的64.7%～92.3%；與各自對照相比,對小麥條銹病正的平均防治效果達到29.6%～45.1%,產(chǎn)量平均增加了4.56%～10.59%。內(nèi)生細菌JD204M具有高效的田間病害控制和促進小麥增產(chǎn)能力。5、利用內(nèi)生細菌JD204M誘導(dǎo)小麥植株系統(tǒng)抗性試驗結(jié)果表明：用內(nèi)生細菌誘導(dǎo)處理后,在整個生育期抗病品種(新原958)和感病品種(矮抗噸產(chǎn)王)小麥葉片的苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、過氧化物酶(POD)、過氧化氫酶(CAT)、超氧化物歧化酶(SOD)活性均比對照有所增強,但兩個品種之間的酶活的動態(tài)變化有所不同；丙二醛(MDA)、超氧陰離子和H2O2含量比對照降低,同時伴隨著脯氨酸、類黃酮含量的增加,可能與內(nèi)生細菌誘導(dǎo)小麥植株產(chǎn)生的抗病性有關(guān)。6、研究了內(nèi)生突變細菌JD204M對14個不同小麥品種分蘗數(shù)、株高、根系活力以及葉片光合特性的影響。結(jié)果表明：用內(nèi)生細菌處理后可提高小麥幼苗的分蘗數(shù),鄭麥9023品種分蘗數(shù)增加最多,比對照提高了34.14%；有12個品種的株高和根系活力分別比對照平均增加9.21%和13.33%；10個品種小麥葉片葉綠素含量和凈光合速率(Pn)分別比對照平均增加7.64%和16.59%；11個品種的蒸騰速率(Tr)和氣孔導(dǎo)度(Gs)分別比對照平均增加10.74%和20.32%,9個品種的胞間C02濃度(Ci)平均減少13.18%。12個品種的光化學(xué)效率(ΦPS Ⅱ)比對照均有所提高,矮抗噸產(chǎn)王增幅最大,為24.20%；11個品種的Fv/FO和Fv/Fm值與對照相比分別增加了19.45%和10.36%。
[Abstract]:Wheat stripe rust is a fungal disease caused by Puccinia striiformis west.f.sp.tritici Eriks et Henn. It is also one of the most serious diseases in Wheat in the world. It has become the main factor affecting the stable yield and high yield of wheat because of its widespread occurrence, high epidemic frequency and heavy damage to the wheat. Resistant varieties, chemical agents and integrated agricultural control measures. However, due to the rapid variation in physiological races and pesticide pollution caused by the application of pesticides, a sustainable and environmentally friendly method for the prevention and control of wheat stripe rust is urgently needed in production. Endophytic bacteria have their unique advantages and diverse biological characteristics. The control of wheat stripe rust with wheat endophytic bacteria is rarely reported. The population diversity of wheat endophytic bacteria was investigated. From the isolated endophytic bacteria, the strains with significant growth promoting, disease prevention and increasing yield were screened from the isolated endophytic bacteria. The main results are as follows: 1, this study carried out the isolation of endophytic bacteria from the healthy wheat samples from different regions, different periods and different organs. The results showed that 313 strains of endophytic bacteria were isolated from the wheat and the endophytic bacteria isolated from the Wolong region of Nanyang were isolated. The number of 101 strains, accounting for 32.27% of the total number of bacteria, the number of endophytic bacteria in different wheat organs is different, the number of endophytic bacteria is up to 11.5 x 105cfu/g in the whole growth period, the number of endophytic bacteria in the stem, leaves and grains is 688 * 105cfu/g, 4.77 x 105cfu/g and 3.47 x 105 cfu/g, and the endophyte isolation in different periods is also deposited. The number of endophytic bacteria in the heading stage was 10.48 * 105cfu/g, the tillering stage, the jointing stage and the waxy mature period were 2.73 x 105cfu/g, 6.65 x 105cfu/g and 9.3 x 105cfu/g. were analyzed by 16S rDNA sequence alignment, and the endophytic bacteria community included 23 Operational taxonomic units (OTU), belonging to 9 genera. For the dominant bacteria group, 76.37% of the total number of bacteria, Pseudomonas sp., 10.23%. Bacillus cereus (B. cereus) and Bacillus subtilis (B.subtilis) have high separation frequency in the whole growth process of wheat, and 9.7% and 4.37%.Stenotrophomonas maltophilia respectively for wheat endophyte as the first report.2, to 1. 27 endophytic bacteria were used to study the effect of endophytic bacteria on the growth of wheat seedlings through indoor and outdoor tests. The results were analyzed by cluster analysis, discriminant analysis and correlation analysis. The results showed that 6 endophytic bacteria (SB127, LD161, RA135, JD204, RC79, RB132) were used to wheat The growth indexes (leaf length, stem and leaf dry weight, root dry weight), the ability to hydrolyse inorganic phosphorus and organophosphorus and the production of long prime are all higher, and there is a significant positive correlation between the growth indexes and the ability of phosphorus removal and the production of long prime. The ability of phosphorus removal and production of endophytic bacteria has a significant effect on the growth of wheat. Different endophytic bacteria promote the growth of endophytic bacteria. 8 6 endophytic bacteria (RC79, SB127, RB132, RA135, LD16, JD204) were identified for 6 endophytic bacteria (RC79, SB127, RB132, RA135, LD16, and JD204), and 2 strains (LD1). 61, JD204) was also identified with rpoD gene, which was initially classified as Bacillus cereus (Bacillus cereus), Bacillus gigantobacilli (Bacillus megaterium), Bacillus subtilis (Bacillus subtilis), Pseudomonas fluorescens (Pseudomonas fluorescens) and Pseudomonas pustinosa (Pseudomonas putida). The optimum growth temperature of 6 endophytic bacteria The optimum growth pH value is 6~8 at 28 to 30 C, and the strain RC79, SB127, RB132 and RA135 can use the glucose carbon source effectively. The strain LD161 and JD204 can be used as the test carbon source except for the xylitol. The 6 strains can almost use all 8 nitrogen sources. All strains except RB132 have detected the arginine decarboxylase and lysine decarboxylase. The colonization test showed that the 6 strains could be colonized steadily in the wheat, and the strain SB127, RB132 and JD204 could transfer.4 to the ground in the wheat. The results of the endophytic bacteria against the 14 different wheat varieties showed that 6 endophytic bacteria RC79M, SB127M, RB132M, RA135M, LD161M and JD204M were used. After treating 14 different wheat varieties, the average incidence of wheat was 14.62% ~ 19.9%, which was about 68.9% ~ 83.4% of the average incidence rate in the control area, and the average disease index of endophyte was 4.98 to 7.13 after treatment, which was about 64.7% to 92.3% of the average disease index in the control area. Compared with the control, the average control effect on wheat stripe rust was 29. .6% ~ 45.1%, the yield increased averagely by 4.56% ~ 10.59%. endophytic bacteria JD204M with high efficiency of field disease control and increasing wheat yield.5. The results of wheat plant resistance test induced by endophytic bacteria JD204M showed that after the induction of endophytic bacteria, the disease resistant varieties (new original 958) and susceptible varieties (dwarf resistance) were treated with endophytic bacteria. The activity of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) in wheat leaves were enhanced, but the dynamic changes of the enzyme activities between the two varieties were different, and the content of malondialdehyde (MDA), superoxide anion and H2O2 was lower than that of the control. With the increase of proline and flavonoid content,.6 may be related to the resistance of endophytic bacteria to wheat plants. The effects of endogenous mutant bacterial JD204M on the number of tillers, plant height, root activity and leaf photosynthetic characteristics of 14 different wheat varieties were studied. The results showed that the endophytic bacteria could improve the wheat seedling score. In the number of tillers, the number of tillers increased most in Zhengmai 9023, and increased by 34.14% compared with the control. The plant height and root activity of 12 varieties increased by 9.21% and 13.33%, respectively. The chlorophyll content and net photosynthetic rate (Pn) of the 10 wheat cultivars increased by 7.64% and 16.59%, respectively, and the transpiration rate (Tr) and stomata of 11 varieties. The conductance (Gs) increased by 10.74% and 20.32%, respectively. The intercellular C02 concentration (Ci) of the 9 varieties decreased on average (Ci) of 13.18%.12 varieties, and the growth of the dwarf resistance tons king was the maximum, 24.20%. The Fv/FO and Fv/Fm values of 11 varieties increased by 19.45% and 10.36%., respectively, compared with the control.
【學(xué)位授予單位】：廣西大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：S435.121.42;S476
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本文編號：1997901