麦秸还田腐熟剂效果增强技术研究

发布时间：2019-03-17 08:03

【摘要】：秸秆还田,作为一种重要土壤培肥与秸秆利用技术,被广泛应用。但在实践中,仍存在诸如影响田间耕作、下茬作物前期生长等问题。为加快还田秸秆腐熟速率或减轻秸秆还田负效应,在秸秆还田的同时接种秸秆腐熟菌,已成为解决秸秆还田负面效应的重要技术。为提高腐熟菌剂接种效果,本研究选用小麦秸秆和筛选得到的高效纤维素降解菌株为研究材料,开展室内模拟试验,探索麦秸还田腐熟剂接种技术,为优化秸秆还田技术提供理论依据。主要试验结果如下：将麦秸按叶片、叶鞘、穗轴、茎及根等不同器官分开,接种娄彻氏链霉菌(Streptomyces rochei),进行为期27 d的腐解试验,研究麦秸不同器官腐解速率差异。试验中分别测定麦秸叶片、叶鞘、穗轴、茎以及根在腐解过程中的干物质损失率、纤维素酶活力、放线菌数量等指标,并进行相关性分析。结果表明：S. rochei能在淹水环境下成为优势菌株；麦秸不同器官腐解速率为：叶片叶鞘穗轴根茎；由于穗轴、茎和根的腐解速率比较慢,且它们占整株麦秸的比重比较大,所以将有机物料腐熟剂接种到麦秸的茎和穗轴器官,可加快麦秸的腐解速率,为秸秆的资源化利用及接种装置在收割机上固定位置的确定提供科学依据。前期已有结果表明,还田麦秸腐解会产生酚酸等化感物质,为探明本试验所用S.rochei是否受到化感物质酚酸胁迫,试验分析了麦秸腐熟过程中化感物质的消长情况及不同酚酸浓度对腐熟菌的影响。试验结果表明：在酚酸浓度条件下,麦秸腐熟菌S.rochei受到了胁迫,低浓度对腐熟菌S. rochei生长繁殖有促进作用；同时,S. rochei的存在缓解了酚酸的积累,S. rochei对酚酸有一定程度的降解能力。模拟田间淹水环境,通过添加保水剂和表面活性剂等不同处理,试探索麦秸腐熟菌接种增强效果技术。试验结果表明：自制麦秸腐熟剂可以显著加快麦秸腐解；添加表面活性剂和保水剂在一定程度上能促进S. rochei的繁殖存活；添加表面活性剂腐解效果最好,同时添加表面活性剂和保水剂处理组的腐解效果仅次于前者,添加保水剂在麦秸腐解前期具有一定的促进效果,但腐解后期效果不明显。通过以上试验,研究发现麦秸茎和穗轴还田后腐解速率较慢,可为接种装置在收割机上位置的固定提供一定的理论参考；麦秸腐熟菌接种效果的不同处理表明,添加表面活性剂和保水剂能在一定程度上促进S. rochei腐解麦秸的效果,可为进一步探索腐熟剂的接种技术提供理论依据。
[Abstract]:Straw return, as an important soil fertilization and straw utilization technology, has been widely used. However, in practice, there are still problems such as affecting field cultivation, the early growth of the next crop and so on. In order to speed up the rate of straw returning to field or reduce the negative effect of straw returning to field, inoculation of straw rot fungus at the same time has become an important technology to solve the negative effect of straw returning to field. In order to improve the inoculating effect of rot-ripening agent, wheat straw and the highly efficient cellulose-degrading strain were selected as the research materials in this study, the simulated experiment was carried out in the laboratory, and the inoculation technology of wheat straw returning to field maturing agent was explored. It provides theoretical basis for optimizing straw returning technology. The main results were as follows: wheat straw was divided according to different organs, such as leaf, leaf sheath, rachilla, stem and root, and inoculated with Streptomyces Louchenne (Streptomyces rochei), for 27 days to study the difference of decomposition rate of different organs of wheat straw. The dry matter loss rate, cellulase activity and actinomycetes quantity of wheat straw leaves, leaf sheaths, spikes, stems and roots during decomposition were measured and analyzed. The results showed that: S. rochei could become the dominant strain in flooded environment, and the decomposition rates of different organs of wheat straw were as follows: leaf sheath, rachilla rhizome; Because the decomposition rate of rachilla, stem and root is relatively slow, and they account for a relatively large proportion of wheat straw, so inoculating organic materials to stem and ear organs of wheat straw can accelerate the decomposition rate of wheat straw, and the decomposition rate of wheat straw can be accelerated by inoculating organic materials into the stem and ear organs of wheat straw. It provides a scientific basis for the utilization of straw resource and the determination of the fixed position of the inoculating device on the harvester. Previous results showed that the decomposition of returning wheat straw produced allelic acid and other allelic substances, in order to find out whether the S.rochei used in this experiment was subjected to phenolic acid stress. The growth and decline of allelopathic substances during maturing of wheat straw and the effects of different phenolic acid concentrations on saprophytic bacteria were studied in this paper. The results showed that under the condition of phenol acid concentration, the wheat straw rot fungus S.rochei was stressed, and the low concentration could promote the growth and propagation of the rot fungus S.rochei. At the same time, the presence of, S. rochei alleviated the degradation of phenolic acid by, S. rochei. Simulated the flooded environment in the field, through the addition of water-retaining agent and surfactant and other different treatment, try to explore the wheat straw rot fungus inoculation enhancement effect technology. The results showed that the self-made maturing agent of wheat straw could accelerate the decomposition of wheat straw, and the addition of surfactant and water-retaining agent could promote the reproduction and survival of S. rochei to a certain extent. The decomposition effect of adding surfactant was the best, and that of adding surfactant and water retention agent was the second only to the former. The addition of water retaining agent had certain promoting effect in the early stage of wheat straw decomposition, but the effect was not obvious in the later stage of decomposition. Through the above experiments, it was found that the decomposition rate of wheat straw stem and spike was slow after returning to the field, which could provide some theoretical reference for fixing the position of the inoculating device on the harvester. The results showed that the addition of surfactant and water-retaining agent could promote the effect of S. rochei decomposition of wheat straw to a certain extent, which could provide theoretical basis for further exploration of inoculating technology of maturing agent.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S141.4

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