施硅对硅细胞的发育及不同光照时间处理海滨雀稗可溶性糖含量的影响

Influences of Si on Si Cells Formation and Content of Soluble Sugars in Seashore Paspulum(Paspalum vaginatum Swarfz.)under Different Light Duration

探讨施硅后海滨雀稗硅细胞的变化及其对光照严重不足时可溶性糖含量的影响。试验设对照(不施硅,CK)和施硅(+Si,K2SiO32 mmol/L)及光照1 h和自然光照(约12 h)处理,观察海滨雀稗叶片硅细胞的发育,测定植株可溶性总糖、蔗糖和还原性糖含量。显微观察结果表明:不施硅时叶尖硅细胞发育不良,叶基硅细胞发育较好;施硅后硅细胞发育完全,数目增多,体积增大,哑铃型突出;表明施硅促进了硅在叶片的沉积。不施硅时,植株可溶性总糖、蔗糖和还原糖含量均为光反映极显著小于12 h光照处理;1 h光照条件下,植株可溶性总糖、蔗糖和还原糖含量均为施硅处理极显著高于不施硅处理;表明光照时间不足时硅有提高可溶性糖含量的作用。施硅后硅在叶片的沉积提高了植株对有限光能的利用,弥补了光照不足引起的光合作物产物可溶性糖含量的降低,提高了草坪草对短日照光强不足的耐性。

This study was designed to elucidate the relations between silicon and content of soluble sugars in seashore paspulum（Paspalum vaginatum Swarfz. ） under different light duration. Different light duration： 1 h light duration and natural light duration （about 12 h） were applied to turf grass under different Si treatments （CK and ＋Si; K2SiO3 2 mmol/L）. Silicon cells were observed in leaf base and tips, total soluble sugars, reductive sugars were determined in the plant of seashore paspulum（Paspalum vaginatum Swarfz. ）. The silicon cells in leaf tip were under-developed compared to leaf base. The silicon cells developed completely in leaf base after silicon application with much more silicon cells of dumbbell shape which indicated that silicon application promoted its deposition in leaves. The content of total soluble sugars,sucrose and reductive sugars in plants were significantly lower in 1 h light duration than in 12 h under CK （P〈0. 01）. It was significantly higher in ＋Si than in CK under 1 h light duration （P〈0. 01）. This indicated silicon increased content of soluble sugars under light shortage. The improved silicon deposition after Si application promoted the use efficiency of limited light, compensated for the decreased of soluble sugar under light shortage,thus enhanced the resistance of seashore paspalum to light shortage.