【作者】 王志坚；

【导师】 刘怀； 许安定；

【作者基本信息】 西南大学 ， 植物保护（专业学位）， 2020， 硕士

【摘要】 微生物菌剂是指利用有益微生物经过共产大量繁殖后能直接或间接改良土壤、预防病虫害、降解有毒物质等作用的加工而成的活菌制剂,其中重茬120是专门针对作物产生重茬的主要原因(养分失衡、土传病害严重、微量元素缺乏、自毒现象),复合经过强化的抗生放线菌及磷钾微再生菌,通过专利技术加工而成。该菌种可以在土壤中进行快速的繁殖,进而激活土壤中被固定的磷、钾及微量元素,并能有效抑制30余种常见土传病害,微生物代谢过程中分泌大量植物生长调节物质,强力促生根并能有效分解土壤残留毒素,从根本上解决重茬问题。有机肥是来源于动植物,可以改良土壤,促进农作物生长,更新土壤中的有机物等的一种富含大量有益物质的肥料,施用有机肥可以促进烟株根系的生长发育,增加根鲜重和根体积,提高了根系活力,从而提高烟株对土壤水分和养分的吸收能力;同时,施用活化有机肥增加了土壤中三大类群的微生物数量,这对提高烟田养分利用效率也可以起到一定作用。烟草青枯病是由青枯雷尔氏菌(Ralstonia solanacearum)引起一种典型的细菌性土传病害,在适宜条件下,该病害的发生蔓延极为迅速,具有显著的爆发性和破坏性,是烟草生产上危害最严重的病害之一。本论文结合了微生物菌剂(主要为“重茬120菌剂”)、普通有机肥,进行重茬120和普通有机肥的联合施用,以探讨最适宜的施用指标,使烟草在人工干预的环境中达到最佳的生长状态。从宏观上调查了微生物菌剂及有机肥施用对土壤的改良作用、对烟草根茎生长的影响。并在此基础上,对施用生石灰配合“重茬120菌剂”,进一步改良土壤酸碱性,改善土壤理化性质,对不同土壤改良剂对烟草生长发育、抗病性及烟草土壤微生物的生态控制进行了探究,主要研究结果如下:1.微生物菌剂及有机肥施用对土壤的改良对伸根期、旺长期、打顶期的烟草做不同处理,发现两种处理下烟草不同生长期土壤pH均接近于7,且没有显著性差异(P>0.05)。两个处理下伸根期土壤pH最高,打顶期最低,但综合来看处理2(重茬120+普通有机肥)pH略高于处理1和对照,说明两者联合施用有利于提高烟草的土壤pH,更有利于烟草的生长。2.微生物菌剂及有机肥施用对烟草根茎病害发生的影响为了探究微生物菌剂和有机肥施用对烟草根茎病害的影响,选择了微生物菌剂(100亿菌剂、重茬120)和普通有机肥处理烟草的伸根期和团棵期,发现微生物菌剂比有机肥更有利于根系生长,伸根期重茬120对根系促进效果更好,团棵期100亿菌剂的促进效果更好。随后进行农艺性状和青枯病发病情况的调查,发现无论是烟草的团棵期还是打顶期,重茬120和普通有机肥联合应用对烟草的促进作用都更明显,且联合施用可以降低烟草4个生长时期烟草青枯病的发病率和病情指数,有利于控制青枯病的发生,提高烟草产量产值。3.不同生石灰用量对土壤酸碱性的影响用50、100、200公斤/亩的生石灰和4公斤/亩的重茬120混合后处理烟草,发现处理会对土壤产生碱性作用,但是处理组的土壤pH(除200公斤/亩外)与空白对照间无显著差异,说明生石灰处理后对种植烟草的土壤的酸碱度影响不大,仍然适于烟草种植;随后发现三种不同生石灰用量处理烟草团棵期,3个处理组和对照组间在烟草团棵期的农艺性状上同样没有显著性差异,说明生石灰处理同样不会影响烟草的正常生长;用这三种不同生石灰用量和重茬120混合后处理,调查烟草团棵期和打顶后烟草青枯病的发病率和病情指数,发现施用生石灰后发病率和病情指数低于对照组。综上所述,烟草种植中添加生石灰后对烟草青枯病有较好的控制作用,也更适于烟草的生长,并且100公斤/亩是最为适合的用量。更多还原

【Abstract】 Microbial agents is referred to those which is beneficial for the soil improvement directly or indirectly,diseases’ and insect pests’ prevention and toxic substances degradation.Among the microbial agents,stubble 120 is the main product designed for the continuous crops(nutrient imbalance,serious soil borne disease,trace elements lacks and the autotoxicity),combined with enhanced antibiotic actinomycetes,phosphate and potassium micro-regenerating bacteria,processed by the patented technology.The microbes can be rapidly breeding in the soil,thereby activating the fixed phosphorus,potassium,and trace elements in the soil,and can effectively inhibit more than 30 common soil-borne diseases.It can also secretes a large amount of plant growth regulators during microbial metabolism and promotes rooting and can effectively decomposes residual toxins in the soil,which can fundamentally solve the problem of continuous cropping.Organic fertilizer is derived from animals and plants,which can improve the soil,promote the growth of crops,and update the organic matter in the soil.It is a fertilizer rich in a large number of beneficial substances.The application of organic fertilizer can promote the growth and development of tobacco roots and increase root fresh weight and root volume and improves root vitality,and thus enhances tobacco plant’s ability to absorb soil moisture and nutrients;at the same time,the application of activated organic fertilizer increases the number of microorganisms in three major groups of soil,which can also plays a role in improving nutrient utilization efficiency in tobacco fields.Tobacco Bacterial Wilt,caused by Ralstonia solanacearum,is a typical bacterial soil-borne disease.Due to the explosiveness and destructiveness,it has become one of the most destructive diseases in tobacco production.In this paper,microbial agents(mainly stubble 120)and the organic fertilizers were combined to find the appropriate application index,so as to achieve the best growth of tobacco in the artificial intervention environment.The effects of microbial agents and organic fertilizers on soil improvement and rhizome growth of tobacco were investigated from a macro perspective.Based on this,the application of quicklime in combination with stubble 120 to further improve soil acidity and alkalinity,and to improve soil physical and chemical properties was explored.The main research results are as follows:1.The application of microbial and organic fertilizers to soil improvementWhen tobacco was in the rooting period,peak period and topping period,there was no significant difference in soil pH between different treatments(P> 0.05),but when comparing the peak period and topping period,the soil pH of treatment 2 was still observed lightly higher than treatment 1 and control.Comparing the different growth stages of tobacco under the same treatment,it was found that as the tobacco grows,the pH of the soil gradually decreases.In a comprehensive view,treatment 2 can improve the quality and yield of tobacco by improving the pH of soil.2.The effects of microbial agents and organic fertilizer application on the occurrence of tobacco rhizome diseasesIn order to investigate the effects of microbial agents and organic fertilizers on tobacco rhizome diseases,microbial agents(10 billion bacterial agents and stubble 120)and organic fertilizers were selected to treat the rooting stage and the clustering stages of tobacco.Results showed that microbial agents was more conductive to root growth than organic fertilizers.The stubble 120 had a better promotion effect during the rooting stage while the 10 billion bacterial agents had the better promotion on the clumping stage.Subsequently we found that the combination of stubble 120 and organic fertilizers had obvious promoting effect to both rosette stage and topping stage of tobacco.At the same time,the experiment also showed that combined application of stubble 120 and organic fertilizer on tobacco could reduce the incidence rate and disease index of tobacco bacterial wilt in tobacco’s four growth periods,which was beneficial to control the occurrence of bacterial wilt and increased the output of tobacco.3.The effect of different amounts of quicklime dosage on soil acidity and alkalinityAfter treating tobacco with 50,100,200 kg/mu of quicklime and 4 kg/mu of stubble 120,it was found that these treatment would have an alkaline effect on the pH of soil,but there was no significant difference between the treatment(except 200 kg/mu)and the control.The results showed that quicklime treatment had little effect on the pH of soil and is still suitable for tobacco cultivation.Subsequently,it was found that there was no significant difference in agronomic traits between the three treatments and the control in the cluster stage of tobacco,indicating that quicklime treatment also had no effect on tobaccos’ normal growth.These three treatments were used on the tobaccos’ rosette stage and topping stage to test the incidence and disease index of tobacco bacterial wilt,and it was found that the incidence and disease index were lower than the control after the application of quicklime.In summary,adding quicklime in tobacco cultivation has a better control to tobacco bacterial wilt and is also suitable for the growth of tobacco.100 kg/mu is the most suitable dosage.更多还原