Studies On Seed Propagation And Tissue Culture Of Ficus Beipeiensis

Ficus beipeiensis S.S Chang, a kind of woody plant in Ficus, is a member of the family Moraceae. It is a dioecious species and distributed only on limestone in the Jinyun Mountains, Chongqing. In 2007, it was rated as one of the ten local garden tree species of Chongqing because of its highly ornamental leaves and fruits. Another it was a plant of critically endangeredone and included in the China Species Red List in 2004. Up to now, there are five wild in dividuals, which can continue the syngarny process and produce active seeds, but whose seedlings were not found in the open. Until now, only cuttage in report about the propagation research of Ficus beipeiensis.Because the material which is less limit the cottage, other means of propagation need. In order to obtain a large number of seedlings in short time, two aspects of reproductive technologies including seed propagation and tissue culture have explored in this study and lay a solid foundation for the artificial reproduction and industrial seedling. The basic results as follows:1. Study on Seed Germination of Ficus beipeiensisThe effect of treatment time of the 98% sulfuric acid (1 min to 20 min),30 ℃ warm water soaking time (4 h to 24 h), germination temperature (20 ℃ to 35 ℃), germination substrate (paper, river sand, vermiculite, mixture of sand and vermiculite which volume ratio was 1:1), illumination condition (darkness,12 h and 24 h light at 3000 lx everyday) and seed soaking with GA3 (50 mg·L-1 to 500 mg·L-1) on the germination of Ficus beipeiensis seeds was compared. The results indicated that the seed could not germinate without acid etch because of physical dormancy. And the appropriate acid scarification time was 3-5 min, the suitable seed soaking time was 4-8 h at 30 ℃, the optimal germination temperature was 25 ℃ and the best germination matrix was river sand. Under these conditions, the germination rate of seeds reached more than 90% in 15 days. Simultaneously, full illumination condition and 300～400 mg·L-1 GA3 soaking (30 ℃,4-8 h) can significantly increase the germination rate of Ficus beipeiensis seeds. The seedling rate in vermiculite reached above 85%, the survival percent of plug and nutrition pot seedlings got above 95%.2. Research on Technology of Seedling Culture of Ficus beipeiensisDuring plug seeding, The experimental material is seedling with seed germination of Ficus beipeiensis. Screening of matrix:nutrient soil, field soil, vermiculite. Screening of matrix:nutrient soil, field soil and mixture of vermiculite and mica which volume ratio was 1:1. Screening of foliar fertilizers both periods:0.5% urea, Hoagland nutrient solution and water. The influence of different substrates and different foliar fertilizers to Ficus beipeiensis of physiological and growth was studied. The main conclusions of the study are list below:During plug seeding, the nutrient soil is the best, field soil is better, vermiculite is poorest; 0.5% urea is the best, Hoagland nutrient solution is better, water is poorest. During nutrition pot seeding, the nutrient soil is the best, field soil is better, vermiculite is poorest; 0.5% urea is the best, Hoagland nutrient solution is better, water is poorest.3. The establishment of in vitro rapid propagation system of Ficus beipeiensisThe stem tips (1.5 cm) of Ficus beipeiensis were used as explants to establish a propagation system in vitro. The results indicated that the stem tip explants were cultured on MS medium supplemented with 1.5 mg·L-1 6-BA+0.05 mg·L-1 NAA for 30 days, the induction rate of the adventitious buds achieved 100% and a propagation coefficient reached 9.2. The adventitious buds were subcultured every other 30 day. The Average multiplication coefficient achieved 7.0 from 1 to 6 generations, and the cluster buds grew well. The adventitious buds were trained on 1/2 MS basal medium for 30 d, their rooting rate was as high as 100%, the root system developed well and the test-tube plantlets grew vigorously. Plantlets were transplanted to matrix soil, survived rate was 97.14% after 30 days’culture。The survival frequency of the seedlings reached 100%, and the young plants grew strongly in the field.4. Early establishment of regeneration system of Ficus beipeiensisIn this study, leaves and petious of plantlets were applied as explants to establish dedifferentiation and redifferentiation in vitro regeneration system. The results showed that the optimal medium for callus induction of petious is MS+2.0 mg·L-1 6-BA+0.1 mg·L-1 NAA, callus induction rate was 79.17% for 30 days, callus grows well. Leaves explants callus induction in MS+2.0 mg·L-1 6-BA+0.5 mg·L-1 IBA is the best, up to 66.67%.