烤烟连作土壤微生物数量及烤烟品质变化的比较

摘要

The soil microbial quantity and quality of flue-cured tobacco were studied in tobacco field , in which crop rotation , 3-year continuous cropping , and 6-year continuous cropping had been carried out .The results showed that:from resettling stage to vigorous growth stage , further to mature period , the bacterial population in the soil reduced gradually , and it was the highest in the soil of crop rotation .The fungal number in the soil of crop rotation was less than that in the soil of continuous cropping , it reached the maximum at resettling stage in the soil of 6-year continuous cropping , and was significantly higher than that in the soil of crop rotation and 3-year continuous cropping .As for the number of actinomyces in the soil , the following order was found:crop rotation>continuous cropping for 3 years>continuous cropping for 6 years; at resettling stage>at vigorous growth stage>in mature period . There were significant differences in some physical characteristics of flue-cured tobacco ( such as filling value , leaf thickness , ten-sion stress, specific weight of leaf and stem ratio ) between crop rotation and 3-year continuous cropping , but the other indexes had no significant difference .As for the chemical properties of flue-cured tobacco , sugar-nicotine ratio , nitrogen-nicotine ratio , ratio of potassium to chlorine , and Schmuck value showed the sequence of crop rotation >continuous cropping for 6 years>continuous crop-ping for 3 years, they were all in the appropriate range , and their coordination in crop rotation treatment was better than that in con-tinuous cropping treatment .The total amount of neutral aroma components ( excluding neophytadiene ) showed crop rotation >contin-uous cropping for 6 years >continuous cropping for 3 years.%研究了轮作、连作3年、连作6年的植烟土壤微生物数量以及烤烟质量的变化，结果表明：细菌数量从团棵期、旺长期到成熟期，呈现出逐步减少的趋势，且轮作土壤的细菌数量最大；就真菌数量而言，轮作少于连作土壤，连作6年的真菌数量在团棵期最大，且显著高于轮作和连作3年；放线菌数量表现为轮作＞连作3年＞连作6年，且团棵期＞旺长期＞成熟期。对烤烟物理特性研究表明，填充值、叶片厚度、抗张力、叶质重、含梗率均表现为轮作与连作3年有显著差异，其余指标不显著；对烤烟化学成分，糖碱比、氮碱比、钾氯比、施木克值均表现为轮作＞连作6年＞连作3年，且在适宜范围内，轮作烤烟的协调性优于连作；中性致香成分总量（不计新植二烯）表现为轮作＞连作6年＞连作3年。