氮素水平与光强互作对‘蓝伞’玉簪生长和光合特性的影响

 以蓝灰类型玉簪‘蓝伞’（Hosta 'Blue Umbrella'）为材料，研究了4种光强（自然光照的100%、50%、30%、10%）和4种氮素水平（盆栽土施尿素量0、0.5、1.5和2.5 g·kg^-1）处理对玉簪生长和光合特性的影响。结果表明：‘蓝伞’玉簪的生长和光合特性受光强、氮素水平以及光氮互作的影响。在同一氮素水平下，随着光照强度的减弱，玉簪的生物量、叶面积、叶片数、光合速率及可溶性蛋白含量均表现先上升后下降的趋势，在30%～50%光强下达到最大值；叶绿素含量则随光强的减弱而增加。在同一光照强度下，随着氮素水平的升高，玉簪的生物量、叶面积、叶片数、光合速率及叶绿素和可溶性蛋白含量均呈先上升后下降的趋势，在0.5 g·kg^-1氮素水平下达到最大值。

The Single and Interactive Effects of Nitrogen Application Rate and Light Condition on Hosta 'Blue Umbrella' Growth and Photosynthetic Characteristics

The single and interactive effects of nitrogen supply and light conditions on Hosta 'Blue Umbrella' growth and photosynthetic characteristics were studied in this paper. The Hosta was cultivated with sands under four kinds of light conditions (100%,50%,30% and 10% of natural sunlight respectively) and four kinds of nitrogen supply (0,0.5,1.5 and 2.5 g·kg^-1 soil respectively).Results showed that biomass, growth characters, photosynthetic rate and soluble protein content increased at first and then decreased as light density decreased in the same nitrogen supply, the suitable light intensities for Hosta 'Blue Umbrella' were from 30% to 50% of natural sunlight. However, chlorophyll contents increased as light density decreased in the same nitrogen supply. In the different nitrogen supply, biomass, growth characters, photosynthetic characteristic, chlorophyll and soluble protein content increased firstly and then decreased as nitrogen supply increased, the suitable nitrogen supply for Hosta 'Blue Umbrella' was 0.5 g·kg^-1.