| 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 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. |
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