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试论灰色系统关联度分析法在生物科学研究中应用的合适性 总被引:1,自引:0,他引:1
灰色系统关联度分析法的主要研究对象是社会经济等非技术的抽象系统。近年来,在生物科学领域如畜牧、兽医、草原等技术性强和具体系统的科学研究中,发现有应用该法分析其试验数据的论文。经研究核实,应用该法分析生物科学研究的数据,似欠合适。这可能是由于该方法本身有不足处,或由于论文作者误用该法。特提出供读者与学者讨论与研究。 相似文献
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哈达门国家森林公园游客量动态预测 总被引:3,自引:0,他引:3
根据哈达门国家森林公园的票房数据,应用灰色系统理论建立旅游量灰色动态模型。基此,对哈园游客量进行了中短期预测,其预测检验精度为93.72。旨在对该园建设、管理等项决策提供科学依据。 相似文献
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以微生物拮抗病原菌是防治病害安全高效的可行手段。通过对果实表面微生物进行筛选鉴定,以期得到一株可以有效抑制灰霉病的生物防治菌株。对拮抗菌株H-1进行形态学特征、生理生化特性分析,结合16S rDNA序列分析和gyrB 基因序列分析构建系统发育树;采用平板对峙法结合果实伤口试验考察拮抗菌H-1在体外及梨果表面的抑菌作用。结果表明:经鉴定H-I菌株为贝莱斯芽孢杆菌(Bacillus velezensis);B. velezensis H-1在体外条件下可显著抑制灰葡萄孢霉(Botrytis cinerea)、细极链格孢(Alternaria tenuissima)和串珠镰孢菌(Fusarium verticillioides)的菌丝生长,其中对灰葡萄孢霉菌丝的抑制作用最强;果实伤口试验表明,1×1011 CFU/mL的B. velezensis H-1可完全抑制梨果表面灰霉菌生长。由此可见,B. velezensis H-1可以有效抑制梨果采后灰霉病的发生。 相似文献
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Christiane Stehmann Maarten A. De Waard 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(2):171-180
Sensitivity of field isolates (121) ofBotrytis cinerea from France (1992), Germany (1979–1992), Israel (1990) and the Netherlands (1970–1989) to the triazoles tebuconazole and triadimenol, the benzimidazole benomyl and the dicarboximide vinclozolin were tested in radial growth experiments. Resistance to benomyl (in 21 to 100% of isolates tested) and vinclozolin (in 25 to 71% of isolates tested) was common in most countries. EC50s (concentrations of fungicides inhibiting radial mycelial growth ofB. cinerea on B5-agar by 50%) for tebuconazole and triadimenol ranged between 0.01–1.64 and 0.4–32.6g ml–1, respectively, and were log-normally distributed. The variation factor (ratio between EC50s of the least and most sensitive isolate tested) amounts 164 and 82 for tebuconazole and triadimenol, respectively. These values are comparable to those for azole fungicides applied in control of other pathogens. Hence, variation in sensitivity to triazoles can probably not explain limited field performance of triazoles towardsB. cinerea. Isolates from south west Germany (1992) were significantly less sensitive to tebuconazole than isolates collected earlier in Germany, Israel and the Netherlands. Such less sensitive populations may contribute to the limited field performance of DMI fungicides towardsB. cinerea. The sensitivity of isolates from south west Germany to tebuconazole was similar to that of DMI-resistant mutants generated in the laboratory. These mutants displayed stable resistance with Q-values (ratio between EC50 of resistant mutant and wild type isolate) between 5 and 20. Sensitivity of field isolates and laboratory mutants to tebuconazole and triadimenol was correlated. 相似文献
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Chitosan-copper complex compared with chitosan alone enhanced suppression ofBotrytis cinerea rot development on four-true-leaf cucumber seedlings in controlled growth chambers. This paper constitutes the first report
of such enhancement. The optimal concentrations for the most effective suppression ofBotrytis development were 0.2 gl
−1 chitosan and 1.6 mmole copper. After 12 days’ incubation, marked and significantly better disease suppression was obtained
with chitosan-copper complex (75% suppression) than with chitosan alone. The chitosan-copper complex could be a very promising
decay control agent for use in both conventional and organic agriculture.
http://www.phytoparasitica.org posting Dec. 18, 2002. 相似文献
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Deanna L. Funnell Christopher B. Lawrence Jeffrey F. Pedersen Christopher L. Schardl 《Physiological and Molecular Plant Pathology》2004,65(6):285-296
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR. 相似文献