本研究通过田间试验评价烟草间作万寿菊对根结线虫的控制效果,与此同时对烟田土壤线虫进行采样、分离及鉴定,分析线虫的群落多样性,以期探究间作对土壤线虫群落的影响.结果 表明,烟草间作万寿菊对根结线虫病的防效仅为30.98％,显著低于1.8％阿维菌素处理.4种不同种植模式下(烟草间作万寿菊、1.8％阿维菌素处理、单种烟草空白对照以及单种万寿菊阳性对照)三个时期共分离到线虫6070条,隶属2纲6目18个属.通过分析发现种植前试验地各小区间土壤线虫多样性较一致,烟草生长期及采收期,不同种植模式下土壤中的线虫群落存在一定的差异,在多样性、均匀度、优势度及丰富度上都表现出一定的变化.

为探究新型杀线剂氟吡菌酰胺对烟草根结线虫病的防效及对烟株生长的影响,2019年研究组在黔西县林泉镇清塘村进行了田间试验,通过病情指数、防治效果以及农艺性状等指标综合评价41.7％氟吡菌酰胺悬浮剂不同用量对烟草根结线虫病的防效及烟株生长的影响.结果表明:使用41.7％氟吡菌酰胺悬浮剂0.05～0.07 mL/株,兑水500 mL后灌根,对烟草根结线虫病的防效为65.94％～68.27％,显著高于常规药剂(10％噻唑膦颗粒剂);该悬浮剂还能明显增强烟草成熟期株高、茎围、最大叶片长、宽、有效叶片数等农艺性状.

The effect of two different extraction methods (vibrating extraction and ultrasonic extraction) on nitrate-N extraction from the same soil sample of tobacco-planting soil was studied to screen the extraction method with the higher soil nitrate-N extraction rate and suitable laboratory detection conditions.Results:The optimal technological condition of the vibrating extraction method includes 60 mL extraction volume,30 min extraction time,45℃ extraction temperature and 160 r/min vibrating frequency and the nitrate-N content in the soil sample is 26.76 mg/kg.The optimal technological condition of the ultrasonic extraction method includes 60 mL extraction volume,30 min extraction time and 15℃ extraction temperature and the nitrate-N content in the soil sample is 26.81 mg/kg.Though the nitrate-N extraction effect of two extraction methods is equivalent,the extraction condition of the ultrasonic extraction method is easier to be controlled and more suitable for mass sample processing.The ultrasonic extraction method has more advantages under the low temperature condition compared with the vibrating extraction method.

[目的]分析我国西南喀斯特典型区有机和常规两种生产方式下烟叶主要化学成分,并探讨其质量特征,为指导有机烟叶长期高效、高质量的生产提供科学依据.[方法]以贵州省金沙县石灰土种植的烤烟K326为供试作物,采用有机和常规两种方式生产烤烟,分别测定6个种植点的上、中、下部烟叶中烟碱、总糖、还原糖、总氮、钾和氯含量及糖碱比、氮碱比、钾氯比.[结果]金沙县有机和常规生产方式的烤烟烟叶主要化学成分烟碱、总糖、还原糖、总氮、钾和氯含量及糖碱比、氮碱比、钾氯比大多处于适中或趋于适中水平,其质量总体较好;烤烟生产方式由常规转为有机后,烟叶的烟碱含量增加,部分达到较高水平,总糖含量和糖碱比降低,且上部叶和下部叶的总糖含量转为适宜水平,钾含量和氮碱比无明显变化.[结论]我国西南喀斯特曲型区烤烟有机生产方式采用的肥料配方应减少有机氮肥、增施钾肥,增强降碱增钾效果,以提高有机烟叶生产质量.

Inordertoevaluatetheecologicaladaptabilityof9flue-curedtobaccovarietiesofGuizhouinNorthwestGuizhou,usingK326as control,field plot experim ents w ere carried out to study the difference in agronom ic characters,econom ic characters,appearance quality, chem icalconstituentsand sensory quality. The resultsshow ed thatthe m ain agronom ic charactersofG uiyan 2,M T-2 and Y Q-1 w assuperior to the control,and the yield,outputvalue,average price and fine tobacco ratio w ere significanfly higherthan those ofthe controlexperim ent.The yield,outputvalue ofG uiyan 2,M T-2 and Y Q-1 w ere 647.25kg/hm 2, 583.35kg/hm 2 and 320.40kg/hm 2,23 053.05 Y uan/hm 2,16 419.30 Yuan/hm2and7117.05Yuan/hm2higherthanthoseoftheCK respectively,withtheappropriatecontentsofinternalchemicalcomponentsand the proper proportion and the relatively high sensory quality. G enerally speaking,G uiyan 2,M T-2 and Y Q-1 w ith excellent com prehensive charactersand good adaptability need furtherstudy and extension and application in N orthw estG uizhou.