冬小麦叶片显微结构和光合特性与产量的关系

Relationship among Leaf Micro-structure,Photosynthetic Characteristics and Yield Traits of Winter Wheat

为了解冬小麦叶片显微结构和光合特性与产量的关系，采用大田跟踪对比调查方法，对8个高产冬小麦品种的叶片显微结构、光合特征及产量性状进行分析。结果表明，小麦不同叶位叶片主要由规则环状细胞组成，各叶位叶片规则细胞的平均环数为1.7-4.5环。随叶位升高，叶肉细胞平均环数及上表皮和下表皮气孔密度均有增加的趋势。各品种旗叶叶绿素含量最大峰值出现在5月10日前后；旗叶可溶性蛋白含量变化与叶绿素含量变化相似，最大值陆续出现在5月7-20日。各品种叶片叶肉细胞平均环数和平均光合速率均以旗叶最高。但品种间光合势、叶源量的差异与叶肉细胞和叶绿素含量并不完全一致。品种间产量性状的差异主要表现在生物产量与经济系数上。生物产量与倒2叶光合势呈显著正相关，与倒3叶光合势呈极显著正相关。综上可见，光合性能好且光合产物能够有效转运进入籽粒，是小麦品种获取高产的必要特征。

In order to verify the relationship among photosynthetic characteristics, leaf micro-structure and yield traits of winter wheat, a field experiment was conducted in Gaocheng, Hebei pronvince, using eight wheat cultivars as experiment materials. The main results showed that leaves at different positions on the main stem of wheat mainly composed of regular mesophyll cells. The amounts of links of regular mesophyll cells ranged from 1.7 to 4.5. The average amounts of links of mesophyll cells and the stomatal density on adaxial and abaxial epidermis all had tendencies to increase with rising leaf positions for all cultivars. The maximum values of chlorophyll content in flag leaves appeared at around May 10 for all wheat cultivars. The dynamics of soluble protein content of flag leaves were similar to those of chlorophyll content with the maximum contents appeared from May 7 to May 20 in different cultivars. The average amounts of links of mesophyll cells and photosynthetic rates of flag leaves were highest among all leaves of wheat plants. The values of photosynthetic potential and leaf source capacity,however,were not entirely consistent with those of the link amounts of mesophyll cells and chlorophyll content among wheat cultivars. Yield differences among cultivars were mainly due to the different biological yield and harvest index. Biological yield was significantly positive correlated（at 0.05 level） to photosynthetic potential of top 2nd leaf,and also significantly positive correlated（at 0.01 level） to photosynthetic potential of top 3rd leaf. According to these results, good photosynthetic performance and high efficiency of photosynthetic products translocation into grains are essential features for a wheat cultivar to achieve high yield.