【摘要】 以紫叶李幼叶为试验材料,于2017年3~5月系统地观测了其发育过程。从叶片大小(以叶面积表示)来看,紫叶李叶片的生长趋势呈明显的"抛物线形"曲线,在5月中旬叶面积达到最大。新生叶展开过程中,叶绿素和花青素含量均逐渐升高,其中叶绿素含量增加较快,5月初即达到最大值;花青素含量则一直呈上升趋势,5月下旬花青素含量仍在升高;蛋白质含量增加趋势与叶绿素一致。随着叶面积的增大,紫叶李叶片的质体醌库大小(Area)和反应中心数目(RCs/CSo)在5月中旬逐渐增大至最大值,PSII最大光化学效率(Fv/Fm)、光能吸收和传递效率(ABS/CSo、TRo/CSo、ETo/CSo)、热能耗散比率(DIo/CSo)等也在5月底逐渐趋于稳定,说明此时叶片的光合功能已经发育完善。更多还原

【Abstract】 In order to better understand the law of growth and development of Prunus cerasifera leaves, the young leaves of Prunus cerasifera were used as experimental materials to systematically observe their development progress from March to May in 2017. From the leaf size(expressed as leaf area), the growth trend of Prunus cerasifera leaves showed a obvious"parabolic"curve, and reached the maximum leaf area in mid-May. Chlorophyll content and anthocyanidin content increased gradually during the process of new leaf unfolding, in which the chlorophyll content increased rapidly and reached its maximum at the beginning of May, while anthocyanidin content had become more and more even in mid-May. The increasing tendency of soluble protein content in leaf is similar to the chlorophyll content. The fluorescence parameters of Prunus cerasifera leaf determined by Handy PEA showed that the quinone pool size(Area) and PSII reaction centers per excited cross section(RCs/CSo) increased gradually to the maximum in mid-May with the increase of leaf area. The maximal efficiency of PSII photochemistry(Fv/Fm), the efficiency of light absorption and transport(ABS/CSo, TRo/CSo, ETo/CSo) and dissipated energy(DIo/CSo) per excited cross section were all gradually stabilized at the end of May. So the photosynthetic function of Prunus cerasifera leaf has been well developed at this time.更多还原