Study On Shade Tolerance And Interplay Under Camellia Oleifera Forest Of Sarcandra Glabra

Sarcandra glabra（Thunb.）Nakai is an evergreen subshrub of the genus sarcandra in the family Chloranthaceae.It is one of the important Chinese medicinal materials for intercropping under forest.In this paper,the photosynthetic characteristics,agronomic traits,active ingredient content and leaf anatomical structure of Sarcandra glabra under different shading treatments were studied;based on the study of shade tolerance of Sarcandra glabra,the resources of Sarcandra glabra from 19 habitats were evaluated;the interplay of Sarcandra glabra under Camellia oleifera forest was studied from different canopy density,soil p H and planting mode.The main results are as follows（1）The results of the study on Photosynthetic and agronomic characters of Sarcandra glabra under the same shading showed that the photosynthetic index of Sarcandra glabra increased first and then decreased with the increase of shading rate,the maximum net photosynthetic rate and daily mean photosynthetic rate of 70%shading Sarcandra glabra were 3.69μmol·m^-2·s^-1、7.45μmol·m^-2·s^-1.With the increase of shading rate,the agronomic characters of Sarcandra glabra showed the trend of increasing first and then decreasing.The agronomic characters of Sarcandra glabra were the best under 70%shading,and the plant height,ground diameter,leaf number,leaf area and total biomass were 58.68 cm,5.09mm,87.33,1038.53 cm²,15.50 g,respectively.（2）The results showed that the content of isofraxidin first decreased and then increased from May to October,and the content of rosmarinic acid first increased and then decreased and then increased.The highest content of isofraxidin was 0.083%when harvested at the end of May,and the highest content of rosmarinic acid and extract were 1.737%and31.37%when harvested at the end of October.The content of isofraxidin was the highest in roots and rosmarinic acid was the highest in leaves.The highest rosmarinic acid content was74.67 mg/g in shade drying and 2.72 mg/g in isopyrimidine drying at 70℃.The content of isopyrimidine in Sarcandra glabra decreased significantly after drying,and the best drying temperature was 70℃.（3）The results of leaf anatomical structure of Sarcandra glabra under different shading treatments showed that with the increase of shading rate,the thickness of upper and lower epidermis cells,palisade tissue and sponge tissue of Sarcandra glabra increased firstly and then became thinner.Under 70%shading treatment,the thickness of upper and lower epidermis cells,palisade tissue and sponge tissue of Sarcandra glabra was the largest,which were 23.88μm,22.74μm,33.66μm and 181.52μm.The results showed that the chloroplast lamellae of Sarcandra glabra under 50%and 70%shading treatments were clearly stacked and closely arranged;compared with the shade loving plant（Epimedium brevicornu Maxim.）,the thickness ratio of palisade tissue to spongy tissue and tissue porosity of Sarcandra glabra were not significantly different;compared with the shade loving plant（Mentha haplocalyx Briq.）,the cuticle of Sarcandra glabra was significantly thinner,spongy tissue was developed,and the thickness ratio of palisade tissue to spongy tissue was significantly decreased,the tissue porosity increased significantly.（4）The results of resource evaluation in different producing areas showed that the plant height,ground diameter and biomass were the highest from Tongdao,which were23.02cm,3.03mm and 2.49g,respectively.The pathogen causing Southern Blight in Sarcandra glabra is Sclerotium Rolfsii.The extract content of Sarcandra glabra from Huayuan producing area was the highest（38.22%）,the isofraxidin content from Mayang producing area was the highest（0.12mg/g）,and the rosmarinic acid content from Suining producing area was the highest（38.05mg/g）.（5）Intercropping Sarcandra glabra under the oil tea forest with canopy density of 0.45,0.68 and 0.85,when the canopy density was 0.68,the net photosynthetic rate was the highest,which was 3.16μmol·m^-2·s^-1,the highest plant height was 38.08 cm,and the maximum biomass was 4.22 g.When the soil p H was 5.02,4.95,3.95 and 3.65,the plant growth slowed down with the decrease of soil p H,when the soil p H was 5.02,the plant height,ground diameter and biomass were 35.13 cm,4.21 mm and 4.02 g,respectively.Among the different planting patterns,the height,ground diameter and biomass of transplanted Sarcandra glabra were 16.81 cm,2.45 mm and 1.49 g,respectively.