海藻多糖与有机物料对烟草青枯病的防控效果

为探究海藻多糖与其他有机物料混合使用对烟草青枯病的防控效果，以烤烟品种NC102为试验材料进行田间试验，设置不同用量海藻多糖与微生物菌肥、草木灰、贝壳粉、生物炭等有机物料的组合处理，分析了不同处理对烟草农艺性状和经济性状、土壤理化性质、烤后烟叶化学成分的影响，以及土壤理化性质与烟草青枯病发病率和病情指数的相关性。结果表明，与对照相比，海藻多糖与有机物料的施用普遍促进了团棵期和旺长期的烟株生长发育，提高了土壤pH和有机质含量，降低了烟草青枯病的发病率和病情指数；烤后烟叶经济性状和主要化学成分也有不同程度的提升。Pearson相关性分析表明，土壤有机质含量和pH与青枯病发病率和病情指数之间存在极显著的负相关关系。500倍海藻多糖稀释液在50~100 mL/株的范围内，用量越高，效果越好；组合处理中草木灰+海藻多糖75 mL/株处理效果最好。通过增加海藻多糖和有机物料，调节土壤pH或增加土壤有机质含量有助于控制青枯病的发生。

Control Effect of Seaweed Polysaccharides and Organic Materials on Tobacco Bacterial Wilt

To investigate the control effect of seaweed polysaccharides and some organic materials on the tobacco bacterial wilt, a field experiment was performed using flue-cured tobacco variety NC102 as the experimental material. A series of experimental trials was designed including seaweed polysaccharides only, and combination of seaweed polysaccharides with organic materials including microbial fertilizer, plant ash, shells powder and biochar. The effect of different treatment on the tobacco agronomic and economic traits, the soil physi-chemical properties, the flue-cured tobacco chemical composition, and the correlations between soil physi-chemical properties and the incidence and disease index of tobacco bacterial wilt were analyzed. The results showed that, compared with the control, the application of seaweed polysaccharides and organic materials generally promoted the growth and development of tobacco during the resetting stage and vigorous growing stage, increased the soil pH and organic matter content, reduced the incidence and disease index of tobacco bacterial wilt, and improved the economic characteristics and the main chemical components of flue-cured tobacco leaves. Pearson correlation analysis showed that there were significantly negative correlations between soil organic matter content, soil pH and the incidence and disease index of bacterial wilt. Application of 500 times diluted polysaccharide with 50~100 mL/plant showed a negative correlation with the incidence index of bacterial wilt, whereas plant ash+seaweed polysaccharide 75 mL/plant treatment showed the best control effect of bacterial wilt in all treatments. Therefore, the occurrence of bacterial wilt can help controlled by adding seaweed polysaccharides and organic materials to adjust soil pH and soil organic matter content.