【摘要】 采用全光照(Lck)与遮荫处理———透光率为71%(L1)、63%(L2)和22%(L3),对雪茄外包皮烟生长发育及其光合特性进行了研究.结果显示:(1)随着透光率的降低,烟株茎变细,叶片变薄;株高和叶面积各处理均先增加后降低,且在L2遮荫条件下株高和叶面积显著高于其它处理,分别达最大值(32.5 cm,47 620 cm2);根系干重显著降低,总干重先增加至透光率为63%时达最大值,当透光率降至22%时又显著降低;净光合效率(Pn)呈先增加后降低趋势,且在透光率为71%的遮荫条件下达最大值;(2)遮荫处理可显著提高雪茄外包皮烟叶绿素含量和Fv/F0值,使ΦpsⅡ、Fv/Fm和QP值增大、QN和Chl a/b的值降低.研究表明,透光率为63%的遮荫处理下雪茄外包皮烟植株地上部分生长最好.更多还原

【Abstract】 The study examined the growth and photosynthetic capabilities of tobacco leaves of cigar-wrapper use under full natural light（control） and shadings at the transmittances of 71%（L1）,63%（L2） and 22%（L3）.It showed that（1） as the transmittances decreased tobacco stems and leaves separately became slender and thinner and the plant heights and leaf areas of tobacco increased firstly and then declined and the plant height and leaf area under the shading at the transmittance of 63%（L2） were significantly higher than those under the other shadings,separately reaching their maximums（32.5 cm and 47 620 cm²）;the root dry weights significantly decreased and the total dry plant weights increased peaking at the transmittance of 63% and significantly declined as the transmittance declined to 22%;the net photosynthetic rates appeared first to rise reaching their maximums under the shading at the transmittance of 71% and then decline;（2） In the leaves of cigar-wrapper use,shading could make the chlorophyll contents,Fv/F₀,Ф_psⅡ,Fv/Fm and QP to increase and the QN and chlorophyll a/b ration to declined.It indicated that the shading at the transmittance of 63% was optimal for the aboveground parts of tobacco plants of cigar-wrapper use to grow best.更多还原