Effects of Root- controlling Reagents on the Growth of Container Seedlings of Aquilaria sinensis

[Objectve] To screen the optimal root-controlling reagents for container seedlings of Aquilaria sinensis( Lour.) Gilg,and to enhance the survival rate during transplanting. [Methods] Three different chemical reagents were selected with the concentrations being 50-200 g / L. Chemical reagents were added into emulsion,and together applied to the inner wall of black nutrition pot. The size of container was50 cm × 50 cm; and substrate ratio was turfy soil∶ perlite = 3∶ 1. After cultivated for three months,the seedling height,ground diameter,principal root length,number and length of primary lateral roots( length > 5 cm) were measured. Data treatment and analyses were carried out by Spss 16. 0 and Excel 2007 software. Effects of different concentrations of chemical reagents on the growth of container seedlings of A. sinensis were compared. [Results] All the three chemical reagents had significant effects on the seedling height,ground diameter,length of principal roots,number and length of primary lateral roots of A. sinensis. Chemical reagents had shortening effects on the average lengths of principal roots and primary lateral roots,and enhanced the number of primary lateral roots. The influencing degrees of three chemical reagents on the growth of container seedlings of A. sinensis were in the order of CuC O3> AlC l3> ZnC l2. Adding 100- 150 g / L CuC O3 could control the lengths of principal roots and primary lateral roots and enhance the number of primary lateral roots. Therefore,100- 150 g / L CuC O3 was selected. [Conclusions] Adding 100- 150 g / L CuC O3 effectively controlled the root system of container seedlings,and enhanced the survival rate during transplanting of A. sinensis.