有色膜覆盖对春大白菜光合特性及产量的影响

以早春拱棚栽培‘菊锦’大白菜为试材,无色棚膜为对照,研究有色棚膜对春大白菜光合特性、生长量及产量的影响。结果表明,在相同光量子通量密度(PFD)下,紫膜和红膜处理的气温较高,空气湿度较低;蓝膜和绿膜的气温较低,而空气湿度略高。各处理大白菜叶片光合速率(P_n)日变化呈单峰曲线型,紫膜和红膜的P_n显著大于对照,而蓝膜和绿膜与对照差异不显著;早春棚栽大白菜的光饱和点(LSP)为1133.4~1217.5μmol·m~(-2)·s~(-1),紫膜和红膜的明显高于对照,蓝膜和绿膜与对照无显著差异。各处理大白菜的光补偿点(LCP)、表观量子效率(AQY)、CO_2补偿点和饱和点差异不大,但紫膜的羧化效率(CE)显著高于对照,绿膜的明显低于对照。晴天中午红膜和紫膜的光呼吸速率(P_r)低于对照,光能利用率(LUE)高于对照。核酮糖–1,5–二磷酸羧化酶(RuBPCase)、果糖–1,6–二磷酸酶(FBPase)、景天庚酮糖–1,7–二磷酸酶(SBPase)和转酮醇酶(TK)的活性多以紫膜和红膜较高,绿膜较低。与对照相比,紫膜和红膜的生长量较大,而绿膜的较小,蓝膜与对照差异不显著。紫膜和红膜的经济学产量分别比对照高15.1%和7.8%,而蓝膜和绿膜的比对照低6.4%和15.5%。可见,紫膜和红膜可提高大白菜叶片的光能利用效率,增强光合碳同化能力,从而促进植株生长,产量明显提高;绿膜处理的结果相反。

Effect of Colored Plastic Film on Photosynthetic Characteristics and Yield of Chinese Cabbage

The effect of colored plastic films on the photosynthetic characteristics and yield of spring Chinese cabbage（Brassica campestris L. ssp. pekinensis）in plastic greenhouse were studied，with‘Jujin’ as material，and colorless plastic film as the control. The results showed that the purple film and red film increased the air temperature，whereas reduces the humidity under the same photon flux density. Conversely，blue film and green film decreased the air temperature，but increased humidity. The daily photosynthetic rate（Pn）of spring Chinese cabbage cultivated in plastic greenhouse varied in a single peak curve. The Pn of purple film and red film plants were significantly higher than that of the control plants， but no differences were observed in blue film，green film and the control plants. The light saturation point （LSP）of Chinese cabbage were 1 133.4–1 217.5 μmol · m-2 · s-1，both significantly higher in purple film and red film than in the control. No differences were found in light compensation point（LCP），apparent quantum yield（AQY），CO2 compensation point and saturation point among different treatments. However， the carboxylation efficiency（CE）of purple film was higher，while that of green film was lower，compared with the control. During sunny days，the noticeable reduction in photorespiration（Pr），but the marked enhancement in efficiency for solar energy utilization（LUE）were observed in red film and purple film plants，compared to control plants. The red film and purple film treatments showed higher，while the green film treatment revealed lower activities of ribulose-1,5-bisphosphate carboxylase（RuBCase），fructose- 1,6-bisphosphatase（FBPase），sedoheptulose-1,7-bisphosphatase（SBPase）and transketolase（TK）than those of the control. The growth was higher in purple film and red film plants，lower in green film plants than in the control plants，but no difference was observed between blue film and the control plants. In comparison with the control，the economics yield of purple film and red film increased by 15.1% and 7.8% respectively，but that of blue film and green film decreased by 6.4% and 15.5%. These data suggest that purple film and red film increase the LUE and photosynthetic carbon assimilation，consequently facilitate the growth and the yield of Chinese cabbage，however the green film showed the opposite result.