Abstract:

New pine hybrids with female parent Pinus elliottii or P. taeda and male parent P. caribaea are popular and their planting area is keeping a rapid growth in recent years. While the cost for hybrid seed production is expensive and the hybrid seedling shortage is increasingly conspicuous. Stem cutting is the important way to solve the problem. In this paper several factors of influencing rooting ability of stem cutting of pine hybrids were systematically studied based on cutting experience recent years. The results showed that the age of donor tree significantly affected the rooting ability, and the survival rate was over 77% for 1~3 years old donor trees, while 45% for 5-year-old trees. The genotype of cuttings was a significant factor of influencing survival rate. Paternal effect was important and the survival rate was different among crosses. Substance and plant growth regulators (GGR) significantly influenced the survival rate, too. The survival rate was higher with the medium perlite, sand or loess only than that with the medium of their mixture, and the GGR with lower concentration was better for cutting’s rooting.