Comparative Analysis of Under-forest Compound Management of Sarcandra glabra from Different Provenances in Low-efficiency Cunninghamia lanceolata Stands

To aim at the widespread distribution of mixed coniferous and broad-leaved forests and the low under-forest space utilization in Qingyuan County, an under-forest compound model based on Sarcandra glabra was established to exploit forest gap resources and build a tree-shrub-herb three-dimensional management system, thereby enhancing forestland productivity and ecological and economic benefits. S. glabra of six provenances were planted under C. lanceolata plantation for two consecutive years to investigate the provenance variation patterns and growth characteristics. The results showed that survival rates among provenances differed significantly under the compound model. The survival rates of three provenances( Qiangangkeng, Qingyuan; Jian’ou, Fujian; and Sanming, Fujian) reached more than 80% after one and two years of planting, representing the increase of 4% ~ 13% compared with those of the local control provenance (Baikeng, Qingyuan). It also showed that growth increment of different provenances exhibited significant differences （P<0.05）, and were also affected by the provenance × replicate interaction. Among the six provenances, Qiangangkeng, Qingyuan and Jian’ou, Fujian provenances exhibited the best seedling height and ground diameter growth in both the first and second years, exceeding by 10.5% ~ 23.8% over those of the control. In the replicated provenance trial, S. glabra of Qiangangkeng, Qingyuan provenance showed strong local adaptability and height growth potential from June to September in the first year with an annual height increment of 90 cm. From June to September in the second year, S. glabra of Jian’ou, Fujian provenance had the largest ground diameter with an annual increment of 0.5 cm, therefore, it is an excellent provenance of S. glabra for under-forest cultivation.