A Study on the Cutting Propagation of Liriodendron chinense X L.tulipfera——II.The Relationship Between the Rooting Percentage and the Diameter of Cuttings and Other Environmental Factiors

The diameter of cuttings,substrates,planting time and other environmental factors for Liriodendron chinense x L.tulipifera are studied with opposite test,uniform test and orthogonal test.The results show that the diameter of summerwood cuttings should be 4 mm~8 mm and the best is 6 mm~8 mm;the diameter of hardy branch cuttings should be 6 mm~10 mm,and the best is 8 mm~10 mm.Anong the four substrates,the Perlite is the best for summerwood cuttings and the plant ash is the best for hardy branch cuttings.The cuttings can be planted during the mid May to the end of August,but the rooting percentage is highest during the 20 days before or after the beginning of June.