Abstract:

 In order to explore the rational planting density and nitrogen level of paddy-tobacco in south Hunan, this paper analyzed the effects of planting density, nitrogen level and their interaction on physical properties of upper flue-cured tobacco by constructing physical properties index and partial Eta2 value from 2 factors experiments. The results showed that: ① Planting density and nitrogen level had different influencial effects on physical properties of upper flue-cured tobacco; planting density mainly influenced leaf openning degree, single leaf weight and thickness of leaf blade; nitrogen level mainly influenced single leaf weight, stem ratio and thickness of leaf blade; the interaction of planting density and nitrogen level mainly influenced leaf opening degree and stem ratio. ② The contribution rate of planting density on physical properties of upper flue-cured tobacco was about 29%; nitrogen level was about 33% and interaction of these 2 was about 38%. ③ The physical properties index of upper flue-cured tobacco increased with the increase of planting density and reduce of nitrogen level. ④ In south Hunan, the better physical properties index of upper flue-cured tobacco was gained by treatment of 18 195 plants/hm2 and 142.5 kg/hm2 nitrogen level.

Key words: upper tobacco leaf, physical property, planting density, nitrogen level

摘要： 为明确湘南烤烟的合理种植密度和施氮量，采用双因素随机区组试验，通过构建物理特性指数及引入偏Eta2值分析了种植密度和施氮量及其互作对上部烟叶物理特性的影响效应。结果表明：①种植密度和施氮量对上部烟叶不同物理特性指标的效应不一致，种植密度主要影响开片度、单叶重和叶片厚度，施氮量主要影响单叶重、含梗率、叶片厚度，种植密度和施氮量互作主要影响开片度、含梗率；②种植密度对上部烟叶物理特性的贡献率为29%左右，施氮量为33%左右,种植密度和施氮量互作为38%左右；③随种植密度的增加和施氮量的减少，烤烟上部烟叶的物理特性指数增高；④湘南烤烟以种植密度18 195株/hm2、施氮量142.5 kg/hm2处理的上部烟叶物理特性相对较好。

关键词: 上部烟叶, 物理特性, 种植密度, 施氮水平