Study On Genetic Diversity And Rapid Propagation Of Podocarpus

Wood materials of Podocarpus are meticulous uniformity, moderate hardness, easy processing, but Podocarpus has little yield of timber. Podocarpus are used in making furniture, stationery, musical instruments and carved timber, and also used as a garden tree species. As the sources of Podocarpus seeds are scarce, Podocarpus seedlings can not be extended and applied in large scale. Therefore, the genetic diversity and rapid propagation technology of Podocarpus were studied in this paper, so as to provide theoretical basis for large scale production and a efficient method of germplasm conservation. The result will promote the process of modernization and exploitation in propagation of Podocarpus. The main conclusions are as follows:1. The genetic diversity of8Podocarpus germplasm materials was study molecular marker technique. Ten out of80primers which were good reproducibility and clear band were selected for SCoT-PCR amplification.136clear bands were got totally and122bands among them were polymorphisms (88.97%). The genetic similarity coefficient among8Podocarpus germplasm materials was in the range of0.39-0.80, which indicated that genetic diversity of Podocarpus was abundant. The clustering analysis of UPGMA system showed that8Podocarpus materials were divided into2groups which were consistent with the result of principal component analysis.The results indicated that SCoT molecular markers were very much effective in the analysis of genetic diversity of Podocarpus, which can be used in identification and classification of Podocarpus germplasm relationship.2. The optimal sterilization method for Podocarpus in tissue culture was that explants were immersed in75%alcohol for30s, then0.1%HgCl2for11minutes. The average contamination rate was45.18percent and the average axillary bud germination rate was47.41percent. 3. GD culture medium is suitable for Podocarpus culture of bud proliferation.4. The best subculture medium formula was GD medium+2mg/L6-BA+0.3mg/L NAA with30g/L sucrose. Bud proliferation was3.15times and this medium could culture best growing buds, green leaf, robust plants.5. The best medium formula for Podocarpus plantlets rooting was1/2MS medium+2.0mg/L IAA+4.0mg/L NAA and1/2MS medium+2.0mg/L ABT-6+4.0mg/L NAA. The rooting rate could reach100%and growth vigor of plant was good.6. In the range of0-200mg/L of ABT-6, the concentration is higher, the mean survival rate of Podocarpus cutting is higher. In the meanwhile, adventitious roots were the more and longer. When the ABT-6concentration was200mg/L, the average survival rate, average adventitious root number and average adventitious root length were maximum, respectively39.26%,6.44roots/cuttings and2.23cm.7. Podocarpus cuttings immersed for10h with30mg/L NAA+200mg/L ABT-6was in the best effect for the cutting surviving. The average survival rate, average adventitious root number and average adventitious root length were maximum, respectively96.3%,12.72roots/cuttings and6.05cm.8. The cutting survival rate of Podocarpus was highest in the cuttage matrix with peat: rice husk:mushroom slag:peanut shell (3:1:1:1). The average survival rate, average adventitious root number and average adventitious root length were maximum, respectively94.82%,10.23roots/cuttings and5.34cm.