烟草赤星病对烟叶产量产值损失率估计研究

目的]研究烟草赤星病对烟叶产量、产值损失的影响。方法]在烟叶采收期分上、中、下部叶3个部位进行赤星病不同危害程度对烟叶产量产值损失率估计研究,并进行回归相关性分析。结果]赤星病病级与烟叶单叶重呈极显著负相关;赤星病病级与单叶重损失率存在极显著正相关。中、上部叶单叶重损失率上升速度明显高于下部叶,上、中、下部叶单叶重损失率分别为3.18%~28.95%、3.43%~28.88%、10.07%~26.90%。赤星病病级越高,烟叶产量、产值越低,损失率越高;相关性分析表明,赤星病病级与烟叶产量和产值均呈极显著负相关,而与产量、产值损失率呈极显著正相关。赤星病对烟叶产值的负影响远大于对产量的影响,烟叶产量损失率最高为28.56%,产值损失率最高可达89.67%。结论]该研究为准确把握赤星病防治的关键时期、减少其对烟叶的危害、提高烟叶产值提供了理论依据。

Loss Rate Estimation of Yield and Output Value of Tobacco Leaf Infected by Tobacco Blown Spot (Alternaria longipes)

Objective] The paper was to study the effect of tobacco blown spot on the yield and output value of tobacco leaf.Method]The upper,middle and lower leaves in tobacco plant were selected during the harvest period of tobacco to carry out loss rate estimation of yield and output value of tobacco leaf caused by different harmful levels of brown spot.Regression correlation analysis was also conducted.Result]The disease levels of brown spot had extremely significant negative correlation with single-leaf weight of tobacco leaf,and it had extremely significant positive correlation with the loss rate of single-leaf weight.The increase speed of loss rate of single-leaf weight of middle and upper leaves was obviously faster than that of lower leaves.The loss rates of single-leaf weight of upper,middle and lower leaves were 10.07%-26.90%,3.43%-28.88% and 3.18%-28.95%,respectively.The higher the disease level of blown spot was,the lower the yield and output value of tobacco leaf was,and the corresponding loss rate was also higher.Correlation analysis showed that the disease level of blown spot had extremely significant negative correlation with the yield and output value of tobacco leaf,and it had extremely significant positive correlation with the loss rate of yield and output value.The negative impact of blown spot on the output value of tobacco leaf was far greater than that on the yield.The highest loss rate of the yield of tobacco leaf was 28.56%,while the highest loss rate of output value reached 89.67%.Conclusion] The study provided theoretical basis for accurately holding the critical period for the control of blown spot,thus reducing the damage on tobacco leaf and improving the output value of tobacco leaf.