遮荫对半高丛越橘光合特性的影响

Effects of shading on photosynthetic characteristics of half-highbush blueberry Northland

以半高丛越橘品种"北陆"为材料,研究了遮荫处理对半高丛越橘光合特性的影响。结果表明,在全光照和半遮荫处理下,净光合速率(Pn)日变化为"双峰"曲线,具有光合午休现象,在全遮荫处理下,Pn日变化为"单峰"曲线;随着光照强度的减弱,越橘叶片的总叶绿素总量、叶面积以及栅/海值逐渐增加,而叶绿素a/b值和比叶重减少;同对照相比,半遮荫2处理的光合特性与全日照无明显差异,是较好的半高丛越橘露地栽培模式。

The photosynthetic characteristics of blueberry under different shading treatments were studied using half-highbush blueberry cuhivar Northland. The results showed that the diurnal variation of leaf net photo- synthetic rate （Pn） showed double-peak curve under full sun light and half shading with photosynthestic midday drop, and single-peak curve under full shading. With decreasing of light degrees, the content of the total chlo- rophyll, leaf area and the ration of the palisade tissue thickness to the spongy tissue increased and specific leaf weight and chlorophyll a/b decreased in blueberry leaves. Compared with full sun light, the full shading was significantly higher in yield of half-highbush blueberry. The half shading 2 was not significantly different with the contrast in photosynthetic characteristics; therefore, it is the preferable open field cultivation pattern for halfhighbush blueberry.