CO_2浓度和光合光量子通量密度对叶用甘薯组培苗光合自养和过氧化物酶活力的影响

EFFECT OF CO_2 CONCENTRATION AND PHOTOSYNTHETIC PHOTO FLUX DENSITY ON PHOTOAUTOTROPHIC CAPABILITY AND PEROXIDASE ACTIVITY OF IPOMOEA BATATAS LAM IN VITRO

以新兴蔬菜叶用甘薯组织培养苗的茎节段作为外植体 ,用MS低糖、无激素培养基进行生根培养 ,设置不同的CO2 浓度 (Ci)和光合光量子通量密度 (PPFD)对组培植株进行环境调控处理 ,获得小植株净光合速率最高的处理组合 (Ci,PPFD) =(872 0 μmolmol-1,2 5 0 μmolm-2 s-1) ,并在此组合下继续培养 2 1d .结果表明 :该调控系统可以有效地调节控制组培苗生长环境中的Ci和PPFD ,提高组培苗的光合自养能力 ,实现低糖、无激素培养 .处理组植株生长健壮 ,叶片数、株高、根鲜重和单株鲜重分别高出CK组 5 7.7% ,10 3.3% ,131.6 %和 2 2 5 .35 % ,叶片和根系过氧化物酶活力分别高出CK组 2 6 .3%和 2 4 .0 % .图 3表 1参

Stems of Ipomoea batatas(L.)Lam in vitro were cultured on MS rhizogenic base medium. Different combinations of CO 2 (Ci) concentration and photosynthetic photo flux density (PPFD) in microenvironment were controlled and recorded by special system. The plantlets getting the highest net photosynthetic rate(P n) were treated by the combination of (Ci=8 720 μmol mol -1,PPFD=250 μmol m -2 s -1). Then, the plantlets had been further cultured for 21 d in such microenvironment. The results indicated that this system could effectively control Ci and PPFD of microenvironment and the photoautotrophic capability of the plantlets in vitro cultured on medium with low concentration sugar and without hormone were promoted distinctly. Compared with those of the control, the leave number, plantlet height , F.W. of root and plantlets cultured in the system were increased by 57.7%,103.3%,131.6% and 225.35%, and the peroxidase activity of leave and root were increased by 26.3% and 24.0%. Fig 3, Tab 1, Ref 18