Tissue Culture Of Pinus Massoniana’s Vegetative Tissues

Pinus massoniana Lamb.(Masson pine) is a pioneer tree species of reforestation in hilly and mountain areas in south of China and occupies an important position in forestry production in China. It is important to carry out researches on rapid regeneration and somatic embryogenesis and establish genetic profiles of Pinus massoniana. The significance of these basic researches is to apply them for the field studies and utilizes them for masson pine production needs.Explants of apical meristems were collected from elite trees of Pinus massoniana in TianJiLing Forestry Station in Changsha, Hunan province. Experiments were designed to discuss the factors that affected on callus induction of Pinus massoniana.1、The best collecting time of Pinus massoniana explants in Hunan province is the period of middle March to late April. Explants collected from this period had the highest callus induction rate of89.8%and the average rate was above80%. Calluses showed white or pale green in color, loose and translucence in construction and moist and toughness in the surface. When observed under a microscope, some embryo-like callus was visible.2、Storage duration had no significant influence on callus induction of Pinus massoniana. Callus collected in April16th,2012still had an84.0%callus induction rate after stored in refrigerator for114days. It is important to collect explants in time and stores them in the refrigerator if you do not have time to place them in cultural media immediately. Furthermore, refrigerator storage treatment could significantly reduce the browning rate of callus.3、The best callus induction media for shoot apical meristem were No.10medium:modified GD+NAA1.0mg/L+6-BA1.0+2,4-D1.0mg/L+CH1000mg/L+Gln500mg/L+Sugar30.0g/L, and No.12medium:modified GD+NAA1.0mg/L+6-BA1.0mg/L+2,4-D3.0mg/L+CHI000mg/L+Gln500mg/L+Sugar30.0g/L.4、When inoculated, the best explants length were0.1-0.2cm. A large quantity of callus cells initiated on the surface of cutting areas, the entire explants were completely differentiated into calluses. The highest callus induction rate was above80%with seldom browning and the lowest contamination rate. The best explant inoculating method was inoculated vertically. In this case, the callus formed earlier with a large number of callus cell population and evenly distributed on both ends. It also had a lower browning and contamination level.5^Hormone TDZ played an important role in callus cell growth and callus cell viability. However, it could not satisfy the normal growth of callus cells when using it alone. Low concentration of hormone KT was not good for callus induction and cell growth. With the increase of hormone KT, browning was reduced gradually and the callus cells grew and developed well. When the concentration of inositol was2.0g/L, the calluses had the best reproduction rate.