不同氮、磷用量对杂种小麦旗叶光合特性的影响

在大田条件下研究了不同氮、磷用量对杂种小麦旗叶光合特性的影响。结果表明,在施N122.5～337.5kg/hm2,P2O590～270kg/hm2范围内,随肥料用量增加杂种小麦旗叶净光合速率(Pn)、叶绿素(Chl)含量、可溶蛋白(Pro)含量、气孔导度(gs)和叶肉导度(gm)均升高,光合功能期延长,叶源量增加。母本(C6-38)与杂种F1表现相同趋势,而父本(Py85-1)在中肥和高肥处理下各指标的表现与杂种小麦相反。在旗叶整个老化过程中,杂种小麦与双亲本均值相比的净光合速率和光合功能期的平均优势均随氮、磷用量的增加而增大,且各施肥水平下均以老化后期大于前、中期。

Effect of N and P rates on photosynthetic characteristics of flag leaf in hybrid wheat

An experiment was conducted in field to study the effects of nitrogen and phosphorus fertilizer on photosynthetic characteristics of flag leaf in hybrid wheat. The results showed that in the range of application of N 122.5—337.5 (kg/hm²) and P₂O₅ 90—270 (kg/hm²), the net photosynthetic rate (P_n), chlorophyll content (Chl), soluble protein content (Pro), stomatal conductance (g_s) and mesophyll conductance(g_m) of flag leaf in hybrid wheat were increased with the increasing rates of fertilizers, and the photosynthetic duration prolonged, therefore, the leaf source capacity increased. All the parameters above of the female parent C6-38 were similar to those of hybrid F1, but the male parent Py85-1 were contrary under the treatments of high and middle fertilizer. During the whole senescence period of flag leaf, the average heterosis of net photosynthetic rate and photosynthetic duration of hybrid F1were increased with the increasing rates of fertilizers, and during the late period of senescence were more significant than those during the early and middle periods.