以实验室筛选得到的具有抗病促生功能的哈茨木霉菌株为材料,研究其不同使用剂量对商洛烤烟生长发育及品质的影响,为哈茨木霉进行烟草绿色生产提供科学依据.2021年在陕西省商洛市洛南县开展哈茨木霉不同使用剂量的小区试验,共设4个哈茨木霉菌剂用量水平:T1(常规施肥+哈茨木霉菌剂0.5 L/hm2)、T2(常规施肥+哈茨木霉菌剂1.0 L/hm2)、T3(常规施肥+哈茨木霉菌剂2.0 L/hm2)和T4(常规施肥+哈茨木霉菌剂3.0 L/hm2),以CK(常规施肥)为对照.结果表明:(1)施用哈茨木霉菌剂的试验组烟株农艺性状、根系发育情况和烤烟抗病性较常规施肥组有明显改善;(2)随着哈茨木霉菌剂用量的增加,烤烟产量、产值及上等烟比例分别较常规施肥处理提高5.09％～12.67％、4.05％～15.05％和8.89％～21.55％;(3)各处理烤烟的糖碱比和钾氯比2个指标整体趋向更佳,有利于烤烟内在品质的提升.哈茨木霉菌剂的增施有利于提高商洛烤烟产质量,其中T3处理(常规施肥+哈茨木霉菌剂2.0 L/hm2)效果最好.

To investigate the effects of new composite water retention agents on the production of flue-cured tobacco in semi-arid areas, we investigated the effects of classical water retention agents（polyacrylate water retention agent and polyvinyl alcohol-acrylic acid water retention agent） and new composite water retention agents（biochar composite water retention agent and potassium humate composite water retention agent） on growth, activities of key enzyme in carbon, nitrogen metabolism, organic acids and conventional chemical composition of flue-cured tobacco through field trials, with no water retention agent as control. The results showed that biochar composite water retention agent and potassium humate composite water retention agent were more effective than the classical water retention agents in increasing the maximum leaf length and root volume, promoting carbon and nitrogen metabolism of tobacco leaves, and increasing the activities of amylase（AL）, neutral transforming enzyme（NI） and nitrate reductase（NR） in tobacco leaves. The biochar composite water retention agent and potassium humate composite water retention agent could significantly increase the total non-volatile organic acids in tobacco leaves. The potassium humate compound water retention agent was more effective, increasing malic acid and citric acid contents by 16.8%, 29.8% and 30.5%, 27.9%, respectively, compared with the control. The treatments also increased the contents of total sugar, reducing sugar, nicotine, potassium and chloride and sugar to alkali ratio in tobacco leaves. Application of new composite water retention agents can be beneficial in promoting flue-cured tobacco production in semi-arid areas.

Some agronomic practices not only promote the development of crop roots and increase overall plant performance but also affect colonisation by rhizosphere microorganisms. However, the composition and temporal dynamics of the tobacco rhizosphere microbiota under different root-promoting practices are poorly understood. Here, we characterised the tobacco rhizosphere microbiota at the knee-high, vigorous growing, and maturity stages under the application of potassium fulvic acid (PFA), γ-Polyglutamic acid (PGA), soymilk root irrigation (SRI), and conventional fertilization (CK) and its correlation with root characteristics and soil nutrients. The results showed that three root-promoting practices notably improved the dry and fresh root weights. Total nitrogen and phosphorus, available phosphorus and potassium, and organic matter contents in the rhizosphere markedly increased at the vigorous growing stage. The rhizosphere microbiota was changed through root-promoting practices. However, with tobacco growth, the change of rhizosphere microbiota showed a pattern of slow first and then fast and the microbiota of different treatments gradually approached. SRI reduced plant-pathogenic fungi but increased chemoheterotrophic and phototrophic bacteria, and arbuscular mycorrhizal fungi. PFA and PGA markedly increased arbuscular mycorrhizal and ectomycorrhizal fungi at the knee-high stage, which benefitted tobacco nutrient absorption. The correlation between rhizosphere microorganisms and environmental factors varied at different growth stages. Notably, the rhizosphere microbiota was more sensitive to environmental factors at the vigorous growing stage, and the interactions were more complex than in other stages. Furthermore, a variance partitioning analysis showed that the influence of root–soil interaction on the rhizosphere microbiota increased with tobacco growth. Overall, all three root-promoting practices could improve root characteristics, rhizosphere nutrient, and rhizosphere microbiota to varying degrees and increase the tobacco biomass, among which PGA had the most obvious effect and most suitable for tobacco cultivation. Our findings revealed the role of root-promoting practices in shaping the rhizosphere microbiota during plant growth and elucidated the assembly patterns and environmental drivers of crop rhizosphere microbiota driven by the application of root-promoting practices in agricultural production.

为了提升云烟99在卢氏烟区的种植水平,充分发挥品种潜力,采用双因素随机区组设计,研究了种植密度(M1:1.20 m×0.55 m,15000株/hm2;M2:1.20 m×0.50 m,16500株/hm2;M3:1.20 m×0.45 m,18000株/hm2)和留叶数(L1:14片/株;L2:16片/株;L3:18片/株)对云烟99的农艺性状、生长发育、经济性状以及烤后烟叶内在化学成分和感官质量的影响.结果表明:种植密度和留叶数对云烟99烟株各部位的生长发育有不同的调控效应;中等种植密度种植条件下,云烟99的田间群体结构较合理,烤后烟叶的均价、产量和产值较高;烤后烟叶总糖、还原糖和钾含量较高,总氮含量较低,化学成分更协调,中上部烤后烟叶的香气量较高,质量较好.综合分析认为,在卢氏烟区现行施肥条件下,适度提高种植密度、增加留叶数,可提高烟叶质量,以行株距1.20 m×0.50 m,留叶18片/株种植云烟99,可获得较佳经济效益.

The changes of microbial biomass carbon,microbial biomass nitrogen,microbial diversity,microbial community structure and driving factors were analyzed in four different years including Y1（fluecured tobacco planting 1 a）,Y2（flue-cured tobacco continuous cropping 3 a）,Y3（flue-cured tobacco continuous cropping 5 a） and Y4（flue-cured tobacco continuous cropping 7 a） of tobacco planting soils in Shangluo area,the hinterland of Qinling Mountains to study the changing characteristics and driving factors of microbial community structure of flue-cured tobacco soil under different continuous cropping conditions.The results showed that the microbial biomass carbon,nitrogen and carbon nitrogen ratio decreased with the increase of planting years,with the decrease of 37.16%,20.40% and 21.10%,respectively.The abundance and diversity of bacteria in soil decreased significantly.The dominant bacteria were Actinobacteriota,Proteobacteria,Chloroflexi,Acidobacteriota and Firmicutes,with the total relative abundance accounting for 80% or more.The abundance of fungi in soil increased significantly.The dominant fungi were Ascomycota,Basidiomycota and Mucoromycota,with the total relative abundance accounting for 90% or more.Under the condition of Y4 continuous cropping,the relative abundance of beneficial microorganisms such as Firmicutes and Desulfobacterota in the soil decreased. The relative abundance of pathogenic microorganisms such as Mucoromycota and Chytridiomycota increased.Long term continuous cropping will reduce the relative abundance of beneficial microorganisms in soil,increase the relative abundance of pathogenic microorganisms,and decrease the carbon nitrogen ratio of soil microbial biomass,thereby increase the risk of tobacco disease.Therefore,the establishment of a good farming system or the construction of microbial community is the key technical way to alleviate or solve the imbalance of microbial community structure in continuous cropping tobacco fields.

为筛选出适宜洛南烟区种植的烤烟新品种(系),于2021年采用小区对比试验,以洛南主栽品种YN99为主对照,K326为副对照,从生育期、植物学性状、主要农艺性状、抗病性、原烟外观质量、主要经济性状方面,对HB1709、湘烟7号、2329、GZ37、1914、1915、1907、Y2001共8个品种(系)进行了适应性评价.结果表明,Y2001和2329综合表现较好,可进一步开展示范验证.

为筛选出适宜商洛北部烟区种植的优良烤烟品种(系),采用小区试验的方法,在商洛北部烟区以当地主栽品种YN99为主对照、K326为副对照,分别对HB1709、湘烟6号、2329、CH02、1914、RY21、CF228、CF227等10个烤烟新品种(系)的生育期、植物学性状、农艺性状、抗病性、经济性状及原烟外观质量进行综合分析评价.结果显示,2329的抗病性、经济效益略优于主栽品种YN99;CH02的生长发育状况、抗病性、上中等烟表现与YN99相当.因此,建议23292和CH02在烟区进一步示范验证.

为探讨普通硅肥和纳米硅肥对烤烟内生真菌种群结构的影响,本试验以云烟99为试验材料,分别于旺长期、现蕾期、圆顶期喷施普通硅及纳米硅,试验处理设置为CK(清水)、T5(普通硅0.17 kg/hm2)、T8(纳米硅0.32 kg/hm2),研究不同硅肥对烤烟内生真菌多样性、组成、结构、化学成分及香气物质含量的影响.结果表明:与CK相比,T5和T8处理均可有效改善烟叶的内生真菌群落多样性、组成、结构及化学成分和总香气物质含量.与CK相比,T5、T8处理的担子菌门(Basidiomycota)的相对丰度增加,分别增加58.14％、37.35％.同时T5、T8处理的线黑粉酵母属(Filobasidium)的相对丰度增加,分别增加113.17％、417.07％.其中T8处理增加了内生真菌的种类,较CK增加31种.通过烟叶化学成分和香气物质与烟叶内生真菌群落组成的相关性分析,得出烟叶化学成分烟碱、可溶性蛋白含量、烟叶香气物质美拉德反应产物含量与烟叶内生真菌群落组成显著相关.因此,叶面喷施纳米硅肥能够使烟叶内生真菌多样性增加,种类增加,改变烟叶化学成分和香气物质含量,对优质烤烟生产具有重要意义.

以废次烟叶为原料,应用酶法辅助乙醇法对烟叶中的绿原酸进行提取,通过单因素试验分析浸泡温度、浸泡时间、浸提温度、料液比4个因素对绿原酸提取率的影响,利用响应面设计对提取工艺进行优化.结果表明,最终优化工艺参数为浸泡温度60℃,浸泡时间1 h,浸提温度90℃,料液比1:25(m:V),废次烟叶中绿原酸提取率为25.709 mg/g,与模型模拟得到的25.863 mg/g基本一致.

为筛选评价适宜洛南县生态条件的烤烟新品种,解决目前洛南烟区品种单一问题,2020年在洛南烟区进行了品种区域适应性研究,对YN121、YN116、中川208、中烟300和YN99(CK)的生育期、植物学性状、农艺性状、抗病性、原烟外观质量、经济性状、内在化学成分及感官质量进行了综合鉴定.结果表明,YN116除内在化学成分协调性比YN99(CK)稍差外,其他质量因素均优于YN99(CK),可作为洛南县烟叶生产的后备品种,进一步开展相关配套栽培技术研究.

为分离筛选对烟草赤星病有良好防效的拮抗菌,以烟草赤星病链格孢菌为靶菌,从蚯蚓粪中经初筛和复筛获得拮抗菌,通过形态、生理生化特征和16S rDNA分析鉴定拮抗菌种类,并对烟草赤星病的防治效果进行了研究.结果表明,筛选出一株拮抗菌Q96,初筛和复筛的抑菌率均超过60％,经鉴定为副地衣芽孢杆菌(Bacillus paralicheniformis),其活菌液(稀释10倍)对孢子萌发和菌丝生长的抑制率分别为73.33％和79.68％,粗发酵液离体防效可达60.04％.Q96菌株可作为抗烟草赤星病生防菌剂的菌种资源.

以‘云烟 99’为试验材料,应用高通量测序技术,主要研究巨大芽孢杆菌及不同施用量对商洛烟田土壤微生物群落特征、烤烟生长及产质量的影响.结果表明,施用巨大芽孢杆菌可有效促进烤烟生长,提高烤烟产量、产值、均价及上等中等烟比例,显著增加烤烟经济效益,其中6 kg/667m2 处理效果最佳.土壤微生物测序结果表明,该区域土壤微生物主要优势菌群为变形菌门和放线菌门,该优势贯穿烤烟整个生育期,另有酸杆菌门、芽单胞菌门、绿弯菌门、厚壁菌门、拟杆菌门等在特定时期表现出一定的优势,本试验所用的巨大芽孢杆菌属于厚壁菌门,该菌在施用后 30 d表现为优势菌群,随着生育期的推进优势逐渐减弱.此外,各菌剂处理微生物多样性指数均显著高于对照,且各处理间微生物群落结构差异显著(P＜0.05).综上所述,巨大芽孢杆菌的应用有效地促进烟草生长,提高了烟草品质,并对土壤微生物群落结构产生显著的影响,研究结果可为该地区微生物菌剂的应用与研究提供理论基础.

[目的]为明确乙酰胆碱对盐胁迫下植物生理的影响.[方法]以烟草细胞为试验材料,观察了乙酰胆碱对盐胁迫下细胞和细胞核的形态,测定了烟草悬浮细胞端粒酶活性、脯氨酸和可溶性蛋白含量、丙二醛含量以及抗氧化酶类(SOD、CAT、POD)活性.[结果]在50 mmol/LNaCl胁迫下,烟草悬浮细胞畸形增多,细胞核变形,DNA浓缩受损,细胞内端粒酶活性显著下降.同时,细胞内的MDA含量显著增加,细胞内膜系统受损严重;细胞内可溶性蛋白和脯氨酸含量降低、抗氧化酶类受损,活性降低.10μmol/L乙酰胆碱处理,细胞内脯氨酸和可溶性蛋白含量显著增加,增强细胞的渗透调节能力;乙酰胆碱能减少MDA的含量,显著提高细胞中SOD、POD、CAT酶活性,增强细胞的抗氧化能力.[结论]为研究乙酰胆碱提高植物的耐盐性机理提供一定依据.

为改善商洛烟区土壤肥力,促进烤烟生长发育,开展了微生物不同菌剂与不同施用量双因素大田试验,对烤烟植物学性状和农艺性状进行分析.结果表明:(1)巨大芽孢杆菌和复合菌剂的低水平处理(A1、C1和C2)的植物学性状相对较优;(2)B4处理株高最高,平均为129.7cm,比对照高12.8％,适量应用微生物菌剂对烟株生长具有良好的促进作用;(3)烤烟茎围B1最大为13.9cm,与对照相比增加12.1％,低水平微生物菌剂的应用能够增加烤烟的茎围,但施用量过多不利于茎围的增加;(4)施用微生物菌剂的各处理烤烟节距均高于对照,其中C1最高为7.77cm;(5)各处理烤烟腰叶长度以C1最高为83cm,与对照相比分别增加12.2％,同一菌剂内不同水平处理表现出不同的增减趋势;(6)各处理烤烟腰叶宽度以C1最高为45.7cm,与对照相比增加15.7％.

为改善植烟土壤环境,提高烟叶产质量,以云烟121为试验材料,通过田间试验,研究不同生物有机肥与无机肥配施对烤烟生长发育及产质量的影响.结果表明,配施有机肥可促进烟株早期早发快长及后期成熟落黄,有效提高烟株茎围和最大叶面积,增强烟株抗病性,改善烟叶化学成分协调性,增加中上等烟比例.各处理以牛粪菌渣有机肥在洛南烟叶生产中使用效果最优.

通过检测和分析烟叶化学成分,探讨陕西秦巴烤烟品质状况,为选择优良品种和配套技术改善烟叶质量提供依据.于2012-2017年,从陕西秦巴烟区重点植烟县采集了197个烤烟样品,对烤烟烟碱、总氮、还原糖、总糖、钾、氯和淀粉等7个化学成分指标的含量分布特征进行了分析.结果表明,氯和淀粉的变异系数远高于其他成分.由偏度值可看出,秦巴烟叶中各化学成分频率分布基本上属于左偏型.不同年份之间的各指标均差异显著,其中2012年各指标明显高于其他年份.总氮、还原糖以及钾含量、氮碱比在不同品种之间差异显著,其中云烟97的钾含量为2.21％,还原糖含量为24.54％,均显著高于其他四个品种.总氮、还原糖、总糖、钾、两糖比在不同地区之间显著差异.不同部位烟碱、氮、总糖、钾含量差异显著.烟碱、总氮、还原糖、总糖、钾在烟叶中的浓度符合正态分布;氮碱比、糖碱比符合对数正态分布.烟碱、总氮、还原糖、钾在烤烟中符合国际型优质烟的概率为80.96％、91.27％、16.01％、75.84％.总体而言,陕西省秦巴烟区整体质量较好,尤其是烟碱和总氮的含量较为符合国际型优质烟标准,云烟97的化学成分协调性优于其他品种,根据不同烟区和不同部位烟叶的烟叶化学成分分布特征,采取技术措施进一步提高其协调性.

为了研究核桃青皮氯仿提取物对烟草蚜虫的毒杀和拒食活性.以氯仿作为提取溶剂并借助超声提取器从核桃青皮中制备氯仿提取物,进一步测定其对烟蚜的毒杀和拒食活性.研究结果表明:氯仿提取物对烟蚜具有很好的防治作用.毒杀活性试验发现在处理48 h后,提取物对烟蚜毒杀效果最佳,烟蚜死亡率最高可达63.35%;与此同时,烟蚜对其同样具有较高的拒食活性,在处理48 h后,拒食率最高能够达到68.73%.总体而言,核桃青皮氯仿提取物对烟蚜具有较好的毒杀和拒食活性,并且呈现良好的剂量-效应和时间-效应关系.

Using water,ethanol,chloroform,ethyl acetate and ethyl ether five different polar solvents,effective components from walnut peel were extracted by ultrasonic extraction,and then the tobacco budworm poison and antifeedant activity were studied.The results showed that five kinds of extracts had toxic effect on tobacco budworm,and showed a good dose-response relationship,different extracts of different concentrations would affect the tobacco budworm toxicity and antifeedant activity.The order of insecticidal activity of five kinds of extracts to the tobacco budworm was ethyl acetate extract>chloroform extract> ethyl ether extract> ethanol extract.Thus,different solvent extracts from walnut green husk has certain toxic effect on tobacco budworm,has potentiality in biological pesticide development.

To explore the different solvent extracts from walnut green husk on tobacco virus growth inhibitory effect. [Methods] Taking Shangluo local production of walnut green husk as raw material, using ethyl ether, chloroform, ethanol, ethyl acetate and acetone five solvent extracts were prepared by refluxing method. The extract was prepared by reflux extraction method, and then the growth inhibition effect of different solvent extracts on tobacco mosaic virus and cucumber mosaic virus was determined by half leaf method. [Results] In the test conditions of different solvent extracts from walnut green husk on tobacco mosaic virus and tobacco cucumber mosaic virus has certain inhibitory effect, and with the increasing concentration of the extracts showed a good dose-response relationship. The ethyl acetate extract effect best, the highest inhibition rate could reach 65.9%, 52.3%, almost no the obvious difference with the positive control of the same concentration. [Conclusion] The ethyl acetate extract of walnut green husk has good control effect on tobacco virus.