【作者】 孙虎；

【导师】 李洪连；

【作者基本信息】 河南农业大学 ， 植物病理学， 2004， 硕士

【摘要】 利用室内平板对峙法对分离和收集的101株放线菌、31株细菌和24株真菌测定了其对小麦全蚀病菌（Gaeumannnomyces. graminis var. tritici）抑菌活性。结果表明，大多数株菌株均对小麦全蚀病菌有一定的抑制作用。在分离的24株真菌中，具有抑制作用的有15株，占分离数的62.50%；在分离的31株细菌中，具有颉抗作用的有10株，占分离数的32.26%；在分离得到的101株放线菌中，有57株具有抑制作用，占分离数的56.44%。结果表明在作物根际中存在着大量的小麦全蚀病菌的颉抗菌。我们从中筛选出对小麦全蚀病菌生长有较强的抑制作用8株生防菌,包括2株细菌EM3和B22，2株真菌T4和F5以及4株放线菌S037、S024、S89和S90。其中4株放线菌主要以抗生作用为主，如S037抑菌带宽达0.9cm；细菌则兼具竞争和抗生作用，如EM3虽然抑菌带宽仅为0.45cm，但其抑菌率却高达60.47%；真菌则主要是竞争作用，如F5和T4，尽管其抑菌带宽仅分别为0.2cm或无明显抑菌带，但它们的抑菌率却最高，分别为65.12%和63.95%。对表现出较强颉抗活性的生防菌株，我们进行了室内盆栽试验,并设化学杀菌剂全蚀净为对照。结果表明,生防菌处理中，颉抗细菌EM3的防效最高，为53.49%；其次为颉抗放线菌S037，防效也达到51.94%，与室内平板对峙试验结果一致。而在平板对峙试验中抑菌率最高，抑制效果最好的两株真菌F5和T4，在此盆栽试验中表现较差。通过室内盆栽人工接种试验对河南省生产上大面积推广和新培育的50个小麦品种（系）的抗全蚀病性能进行了鉴定和评价，结果发现品种间抗性存在明显的差异，但整体抗性较差，无免疫和高抗品种，达到中抗水平的有科优1号、豫展9705、豫58-998、矮早4110、<WP=9>新麦11号、高优505、豫麦18号和豫麦49号八个品种（系），占所有供试品种的26.7%。进一步对其中40个小麦品种进行了田间自然病圃试验,并调查了白穗率, 比较了在盆栽试验与大田试验条件下，不同小麦品种对小麦全蚀病的抗病性差异。结果表明，盆栽试验中达到中抗水平的矮早4110、强筋1号、豫展9705、科优1号和新麦11号其平均白穗率分别为0.96%、1.13%、1.20%、1.53和1.60%，抗性较强；达到高感水平的温优1号、豫优1号、小偃803和豫麦25号在大田试验中白穗率分别达到9.46%、8.90%、8.36%和7.84%，抗性较弱，此与盆栽试验结果基本一致，尤其是矮早4110其平均病指较低、平均白穗率为0.96%，可作为较好的抗性材料, 可以考虑在重病田示范推广，以减轻病害的危害。而在盆栽试验中达到中感水平的豫58-998和高感水平的科麦2号在大田试验调查结果中则显示较低的白穗率，仅为0.28%和0.93%，显示出大田试验与盆栽试验的不一致性。另外，在盆栽试验中均达到中感水平的郑98、国麦1号和高优503，其平均白穗率最高，与盆栽试验结果不甚一致，均表现出较弱的抗病性。通过对不同抗感的小麦品种根际微生物的区系分析，结果表明，不同抗、感的小麦品种的根际和根表微生物的数量、种数及优势种均存在一定差异，一般表现为抗病品种根际中具有更大的微生物群体。说明根际微生物区系组成的差异对小麦品种的抗性具有明显的影响。可能是不同小麦品种对全蚀病具有抗性差异的因素之一。更多还原

【Abstract】 For the 101 isolates of actinomycetes, 31 isolates of bacteria, 24 isolates of fungi, the dual cultures were tested in vitro. The results showed that most microbes have given inhibition effects in some degree, but a several of them had probiosis effects more or less instead of inhibition effects. Among them we sifted 2 isolates of bacteria, EM3 and B22, 2 isolates of fungi, T4 and F5, and 4 isolates of actinomycetes, S037, S024, S89 and S90, which have better inhibition effects to Gaeumannomyces graminis var. triciti, their inhibition rate were 50.70%, 42.25%, 61.97%, 64.79%, 54.93%, 50.70,5 0.70和52.11% . The results showed that the major effects in actinomycetes is antibiosis effects, the important effects in bacteria is both competition and antibiosis, and is competition effects in fungi.We did pot experiments to the microbes which have better antagonistic effects. The results showed that EM3 have the best control effects, the number is 53.49%, the second one is S037, the control effects is 51.94%, the results is consistent to the results on dual cultures, but F5 and T4 which have the best inhibition rate on dual cultures in vitro put up the worst control effects on pot experiments, the control effects of isolate T4 is 6.99% only and even F5 show minus control effects.Resistance identification and evaluation to resistant ability to wheat take-all disease of 50 different wheat cultivars by pot experiment were presented. It showed that the whole resistance is relatively worse in spite of there is obvious discrepancy among these different wheat cultivars .There are no IR and HR wheat cultivars ,but eight wheat cultivars had got to MR level and the ratio of MR wheat cultivars is 26.7%.We did field plot experiments to 40 wheat cultivars and investigated the ratio of <WP=71>non-seed, then compare the consistence of the resistance to wheat take-all of different wheat cultures in pot experiments and field experiments. The results showed that MR wheat cultures in pot experiments, Aizao 4110, Qiangjin 1, Yuzhan 9705, Keyou1 and Xinmai11, get to lower rate of non-seed and higher resistance in field experiments; HS wheat cultures in pot experiments, Wenyou1, Yuyou1, Xiaoyan803 and Yumai25, show lower resistance in field experiments, the results is consistent to the trend in pot experiment. And Aizao4110 is better one, its average disease index is lower and average non-seed rate is 0.96%, we can look it as better resistance material and use it in heavy disease fields to decrease the disease damage. MS wheat culture in pot experiments Yu58-998 and HS wheat culture Kemai2 show lower ratio of non-seed in field experiments, is 0.28% and 0.93%, the results aren’t consistent to pot experiments. And MS wheat cultures Zheng98, Guomai1 and Gaoyou503, their ratio of non-seed are all the most higher and show weaker resistance. It is also different to the results in pot experiments.Through the analysis of the rhizosphere microbes to different resistant or sensitive wheat cultivars we know that different resistant or sensitive wheat cultivars all influence the quantity, varieties and superior variety or dominant community of rhizosphere microbes. The influence and changes of different wheat cultivars to the rhizosphere microbes is also one of the important mechanism of resistance or endurance to wheat take-all disease expect for growth circumstances and haleness among different wheat cultivars.The article identifies quantity distribution, varieties and superior variety of rhizosphere microbes to different resistant or sensitive wheat cultivars, it provides theoretic foundation and practical skills to further define the happening and development of wheat take-all and effective control wheat take-all.更多还原