【摘要】 对青花菜几个品种的光合特性作了研究 .结果表明 ,在塑料大棚内青花菜光合速率 (Pn)日变化呈“单峰”曲线 ,未发生“午休”现象 ;气孔阻力 (Rs)日变化呈先降后升的趋势 ,其与 Pn 的关系呈显著负相关 ;而蒸腾速率 (E)日变化则呈“双峰”曲线 .光通量密度 PFD与 Pn 的关系呈二次函数式 ,并求得里绿的光饱和点为 10 70 .0μmol· m-2 · s-1,光补偿点为 81.0μmol· m-2 · s-1.另外 ,随 PFD的升高 ,Rs 逐渐降低 ,而 E则增大 .水分处理中以 6 0 %土壤湿度下光合速率最高 .供试 8个品种间光合速率有一定差异 ,但差异不显著更多还原

【Abstract】 The photosynthetic property of several varieties of broccoli was studied. The results showed that the curve of diurnal variation of net photosynthetic rate of Broccoli leaf cultivated in plastic greenhouse demonstrated a single peak, and that of the transpiration rate demonstrated two peaks. Light saturation point and light compensation point of photosynthesis in Lilv leaves were 1070 μmol·m -2·s -1and 81μmol·m -2·s -1 respectively. Moreover, R s decreased and E rose with the creasing of PFD. And the optimum water content in soil for photosynthesis was 60%. Obvious differences were not observed among the 8 varieties of Broccoli.更多还原