Allelopathy Journal

In this study, allelopathic potential and chemical components of root exudates from L. gmelini on J. mandshurica were investigated. The root exudates of L. gmelini at different concentrations stimulated the biomass, chlorophyll contents and soluble sugar in of J. mandshurica seedlings. The application of 0.001, 0.01, 0.1, 1.0 g.L⁻¹ concentrations of root exudates increased the seedlings biomass by 1.45, 1.32, 1.17 and 1.14 times over the control. Likewise, the applied root exudates of L. gmelini at 1 g.L⁻¹ concentration and the fraction extracted by chloroform from L. gmelini root exudates at 1.0 g g.L⁻¹ and 0.1 g.L⁻¹ concentrations increased the soluble sugar content by 1.30, 1.24 and 1.22 times over control. Using the liquid chromatography/mass spectrum (LC/MS) technique, several types of compounds (phenolics, catechins and abietane diterpenoids) were identified in the root exudates of L. gmelini. Some of these compounds (catechins, lariciresinol and secroisolariciresinol) act as allelochemicals and stimulated the growth of J. mandshurica seedlings. Thus the root exudates of L. gmelini have stimulatory allelopathic effects to improve the productivity in J. mandshurica plantation in inter-planting with L. gmelini. Thus the establishment and management of Manchurian walnut (J. mandshurica) can be improved by inter-planting with larch (Larix gmelini) in Northeast China.