【摘要】 以NC89烟草品种为材料,用白纱布遮荫研究了100%、80%、50%和20%全光照处理对烤烟生长发育、光合特性及化学成分的影响.结果表明:(1)随光照强度的减弱,植株茎杆变细,叶片的长宽比增加,叶片数减少,出叶速度变慢,干物质重逐渐减少,并以80%的全光照条件下的株高、叶面积最大.(2)净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、叶绿素a/b值均随光照减弱而逐渐下降,胞间CO2浓度(Ci)、叶绿素含量逐渐升高;叶绿素荧光参数Fm、ФPSⅡ、Fv/Fm、QP值逐渐增加.(3)烟碱、淀粉、还原糖、水溶性总糖、总酚含量随光照减弱而降低,而总氮和钾含量升高.综合分析各项测定指标发现,在大于或等于80%全光照(光照强度为770~1 125μmol?m-2?s-1)条件下,烤烟的生长指标变化不大,品质指标符合不同卷烟工业需要,适合优质烟叶的生产.更多还原

【Abstract】 This paper examined the growth,photosynthetic capabilities and chemical composition of flue-cured tobacco under full light(100%) and light intensity at the transmittances of 80%,50% and 20%.The results showed that:(1)With the reducing light intensity,tobacco stems became slender,the ratio between leaf long and wide increased,the number of leaves and total dry matter decreased.The plant height and leaf area under 80% full light condition were significantly higher than those under the other light intensity.(2) Photosynthetic indicators of Pn,Gs,Tr,Chl a/b decreased under low light,but Ci and chlorophyll contents increased,as well as fluorescence parameter of Fm,ФPSⅡ,Fv/Fm,QP.(3) As the reducing light intensity,starch content,reducing sugar content,total sugar and total phenol content lowed and total N and K content increased.更多还原