播期对桔梗光能利用及产量的影响

为了探讨不同播期对桔梗冠层光能利用及产量的影响，揭示不同播期桔梗的有效利用方式，为桔梗栽培技术的完善和建立提供依据。采用LP-80植物冠层分析系统研究春播和夏播2种播期桔梗冠层光合有效辐射、截获率、转化率、利用率等指标，比较其地上部和根部各项农艺性状并做相关性分析。结果表明，当年收获期春播桔梗株高、主根长等农艺性状优势明显，但叶片衰老脱落严重，冠层透过率高，光能利用率低，而夏播桔梗冠层仍有较强光合效率，但冠层反射损失较大。春播桔梗当年产量高、根型好，适合用做1年药用栽培，可在10月底起挖；夏播桔梗在10月中下旬冠层光能利用仍维持在较高水平，适于做2年食用栽培。

Effects of Sowing Date on the Light Use Efficiency and Yield of Platycodon grandiflorum

Aim: By comparing the growth and light use of spring and summer sowing platucodon gradiflorums, this paper provided a scientific cultivation technique. Methods: The agronomic traits, yield, canopy photosynthetically active radiation, interception rate, conversion rate and utilization were investigated. Results: Although the spring sowing had the advantage of the the root yield, but solar energy utilization is low. While the summer sowing still had a strong photosynthetic capacity, the roots continue to grow. Conclusion: Spring sowing had high yield and good root type, were suitable for use as a medicinal cultivation, digging in the end of October; the canopy radiation utilization of the summer sowing remained at a high level, suitable for making 2-annual food cultivation.