核桃-冬凌草复合系统内光合有效辐射对冬凌草生理生长的影响

Effects of photosynthetically active radiation on physiological growth of Rabdosia rubescens in walnut-rabdosia rubescens compound system

以核桃-冬凌草(Rabdosia rubescens)复合系统中冬凌草为研究对象,对复合系统内光合有效辐射(PAR)、冬凌草净光合速率(Pn)、蒸腾速率(Tr)及其生长品质进行测定分析,为当地林药复合模式优化提供参考。结果表明,复合系统内PAR呈现中间高两侧低的趋势,PAR较CK降低了62.77%。复合系统内冬凌草Pn与Tr表现为距离核桃树越近光合能力越差,空间上表现为M>W1.5>E1.5>W0.5>E0.5,Pn、Tr分别低于CK 55.35%和19.63%。复合系统冬凌草平均株高和产量分别为46.90 cm和830 kg·hm^(-2),为CK的70.14%和18.86%。复合系统和CK的冬凌草甲素含量分别为0.58%和0.87%,均可达到药用标准(0.25%),复合系统内各测点甲素含量表现为W1.5>E1.5>M>E0.5>W0.5。PAR与冬凌草Pn、株高、产量和品质之间均极显著相关(P<0.01),与Tr显著相关(P<0.05)。复合系统树冠的遮荫导致树行内不同空间处的PAR有不同程度的降低,直接影响冬凌草的光合特性以及生长品质。因此,可通过对核桃-冬凌草复合结构优化配置,提高光合有效辐射,进而提高冬凌草的光合作用和产量。

In this paper,rubescens in the compound system of walnut and rubescens was taken as the research object,the PAR,Pn,Tr and growth quality of rubescens were measured and analyzed in the compound system,in order to provide reference for the selection of local forest-drug compound model optimization.The results were as follows:PAR in the compoud system showed a trend of high in the middle and low on both sides,and the average PAR of the compound system was 62.77%lower than that of CK.The Pn and Tr of the leaves of rubescens in the compound system showed that the closer to the walnut tree,the worse the photosynthetic capacity was,showing in space as M>W1.5>E1.5>W0.5>E0.5.The Pn and Tr of the rubescens leaves in the compound system were 55.35%and 19.63%lower than those of the CK,respectively.The plant height and yield of the compound system were 46.90 cm and 830 kg·hm^(-2),respectively,which were 70.14%and 18.86%of those of the CK.The content of oridonin in the compound system and CK was 0.58%and 0.87%,respectively,both meeting the medicinal standard(0.25%).The oridonin content was shown as W1.5>E1.5>M>E0.5>W0.5 at each measuring point in the compound system,indicating that the differences were not significant(P>0.05).PAR was extremely significantly correlated with Pn,plant height,yield and quality of rubescens(P<0.01),and significantly correlated with Tr(P<0.05).Shading in the compound system resulted in the decrease of PAR at different locations in the tree line,which directly affected the photosynthetic characteristics and growth quality of rubescens.Therefore,the photosynthetic rate and yield of rubescens could be improved by optimizing row spacing configuration of walnut and rubescens to increase the PAR.