为探索适合连州烟区烤烟生产的最佳透光率地膜,采用不同透光率地膜为材料,研究了地膜对烤烟生长发育及产量的影响.结果 表明:透光率为50％的纯黑色地膜能缩短烤烟大田生育期,增加烟株的株高、茎围、有效叶片数和最大叶面积,增强烟株抗病性,能在一定程度上提高烟叶的产量、均价和上等烟比例.

[目的]明确烤烟组培苗与常规苗在光合特性及产质量方面的差异.[方法]以烤烟品种(系)K326、粤烟97、华烟06的组培苗与常规苗为试验材料,研究组培苗与常规苗的叶绿素含量、硝酸还原酶(NR)活性、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)等光合指标,并对烤后烟叶的化学品质及经济性状进行比较.[结果]大田生育期间,各处理的叶绿素含量、NR活性及各项光合指标均表现为先上升后下降的变化趋势;旺长期前,不同品种(系)组培苗与常规苗间差异不大,从旺长期到成熟期,组培苗各项光合指标均在不同程度上优于常规苗,尤其是在成熟期,K326、粤烟97、华烟06组培苗的叶绿素含量分别比常规苗高15.58％、8.63％、10.07％,NR活性分别高18.57％、2.26％、13.13％,Pn分别高10.15％、7.53％、7.88％.相同品种(系)组培苗内在化学品质较常规苗均有所提升,且中部叶优势更为明显;相比较而言,K326组培苗的总糖、还原糖、淀粉含量及糖碱比均有突出表现,华烟06次之;结合经济性状来看,产值最大的是华烟06组培苗,而均价和上等烟比例最高的是K326组培苗.[结论]从光合特性、烤后烟叶化学品质及经济性状的综合分析来看,烤烟组培苗与常规苗相比较在各方面都具有优势.

为比较烤烟组培苗与常规苗烟苗素质及大田期的抗性差异,以烤烟品种(系)K326、粤烟97、华烟06的组培苗与常规苗为试验材料,测定了苗期农艺性状及根系活力和大田期多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)、抗坏血酸过氧化物酶(APX)、β-1,3-葡聚糖酶等防御性酶活性,并调查了田间发病率.结果表明;组培苗在株高、叶数、茎围、根系体积、根系活力、干鲜重等方面均优于常规苗.在整个大田生育期内,不同处理烤烟的防御酶活性基本呈现出上升—下降—上升的变化趋势.旺长期前,组培苗与常规苗之间防御酶活性差异不大,旺长期受到病虫害侵染后,各处理的防御酶活性均先下降然后上升,并在较长一段时间内处于较高水平,且组培苗防御酶活性增加的幅度高于常规苗,其中K326组培苗的PPO、PAL、β-1,3-葡聚糖酶活性分别比常规苗高出29.58％、15.30％、73.03％,华烟06组培苗APX活性高于常规苗58.43％,差异显著.组培苗的花叶病、气候斑病及虫害发生率等均低于常规苗,表现出较强的抗性.

综述了国内烤烟在水渍、干旱、盐渍等非生物胁迫逆境下的生理反应及抗性方面的研究进展,并提出了今后几个重点研究方向,以期为烤烟抗逆育种提供参考.

Effects of different nitrogen levels on agronomic characters,chemical compositions,yield and production values of Huayan06 were studied.The results showed that plant height,number of leaves and the biggest leaf area were promoted under increasing nitrogen,but effects were not obvious under too much nitrogen.Contents of starch and total soluble sugar decreased with adding nitrogen,but that of nicotine increased.Chemical compositions and coordination of middle leaves under middle or high nitrogen were suitable,but those of upper leaves were suitable under low nitrogen.The yield,production values and average price were best under middle nitrogen.From comprehensive comparison of agronomic characters and chemical compositions,the suitable nitrogen of the new variety Huayan06 in Qingyuan was 165 kg/hm2.

To invesitgate the effects of clipping on seedling quality and physiocological characterstics after transplanting of flue-cured tobacco,Huayan 06 was used as the test material,the agronomic charactere and physiological metabolism indices after transplanting under different clipping times were measured.The result showed that more clipping times restrained significantly plant height,increased fresh and dry weight of biomass below ground level and reduced the water content of tobacco seedling,and increase chlorophyll content and activity of nitrate reductase significantly,soluble protein contents but not significantly.Total root absorbing area,root active absorbing area and volume of roots were the best with 3 clippings.

The relationship between the chemical compositions of flue-cured tobacco(B2F and C3F) in Guangdong's 6 counties and geographical,ecological characteristics was studied.The results showed that the characteristics of Wuhua and Meixian's tobacco was High-carbohydrate content and Low-nitrogen compounds content,because of good light and heat conditions.Jiaoling's tobacco had low-carbohydrate content and high-nicotine content being related to its large rainfall and high-temperature.Nanxiong's tobacco characterized by low –total-sugar content,low-reducing-sugar content,high nicotine content in upper leaves and low nicotine content in middle leaves,had some connection with alkaline soil.The feature of Lianzhou's tobacco was high total sugar content,high reducing sugar content and high nicotine content in upper leaves,having to do with its soil and too much rain in mature stage.

Experiment results pointed out that,the optimum N,P,K level to planting flue-cured tobacco in Zisetu dry land is:N6 kg,P6~7 kg,K12.5 kg per 667 m2,and in Niugantu paddy field is N9 kg,P8 kg,K12.5 kg per 667 m2.

连州晒黄烟已有240多年的历史,其典型代表"星子烟"因具有"浓、香、醇"的特点和劲头较大、香味浓郁独特、吃味醇和饱满的风格而享誉中外.连州晒黄烟地处南岭丘陵烤烟晒烟区,属地方性深色晒黄烟,介于淡色晒黄烟和晒红烟之间,采用全晒的调制方法.烟叶香型独特,为晒黄调味型,评吸质量较好,可以作为烤烟型和混合型卷烟的优质原料,在卷烟配方中可起到调香、调味作用.