Study on the Tissue Culture and Seed Germination Rate Modelling of Highbush Blueberry
|School||Zhejiang Normal University|
|Keywords||highbush blueberry tissue culture seed germination modeling|
Blueberry (Vaccinium corymbosum) belonged to Ericaceae Vaccinium. It is a famous fruit for its high nutritive value and medicinal value ascribed to the highest level of anthocyanin. Derived from America in the 1930s, a series of commercial cultivars had been developed. The main economic commercial species included highbush Blueberry, lowbush Blueberry and rabbiteye Blueberry. Among them, highbush blueberry is one of the most widely distributed species, ascribed to its good characters such as high fruit quality, good soil adaptability, high temperature resistance and low chilling requirement.In this experiment, using highbush blueberry (Brigitta, Misty and Sharpblue) as plant materials, tissue culture combined with seed germination were studied to explore the breeding technology of this fruit.In the study of tissue culture, different sterilization method, basic media, hormone combinations, and different rooting conditions systematically were screened to obtain an efficient and rapid propagation technology, which aimed to provide some helps to the introduction and commercialization of highbush blueberry in Zhejiang province.In the experiments of seed germination, different concentrations of GA3 were used to improve the six species highbush blueberry seed germination after the two weeks cooling disposed. The method of mathematics modeling also applied to found the relationship between gibberellin and the seed germination rate. The mathematical model was established, and trying to get the optimal GA3 addition for the seed dormancy relieving and seed germination. Our work would help to breed new cultivars and improve breeding multiplication.The results were summarized as following:(1) The pathogen can be effectively controlled by the solution of 0.5% brome geramine (10 min) combine with 0.1% mercuric chloride (8 min, add 2-3 drops of Tween).(2) For the screening of the basic culture medium, WPM AN and MS were available for the tissue culture of highbush blueberry. However, WPM and AN were more efficient than MS.(3) The value of pH greatly influenced on its tissue culture, and pH 5.0 were the most optimum value for the number and the length of induced axillary bud.(4) The cultivars of highbush blueberry differed greatly on the propagation rates. Among these three species, Brigitta had the highest rate, followed by Mist, and then Sharpblue.(5) In the induction of axillary buds, ZT play a vital important role rather than NAA.(6) The results also indicated that Brigitta cultivate under dark with WPM+ZT 2.0 mg/L for two weeks, and then transferred to the subculture medium with WPM+ZT 1.0 mg/L; under dark with WPM+ZT 4.0 mg/L+NAA 0.5 mg/L for two weeks, subculture medium with WPM+ZT 4.0 mg/L and cultivate under WPM+TDZ1.0 mg/L+NAA 0.5 mg/L, adventitious buds using leaf could induce effectively. Sharpblue cultivate under dark with AN+ZT2.0 mg/L and then transferred to the subculture medium with AN+ZT 0.5 mg/L, adventitious buds using leaf could induce effectively too.(7) Light play a vital role in the induction of the rooting in tissue culture. The treatment of out test-tube rooting was most efficient for the rooting, followed by inside test-tube rooting with 0.8 g/L activated carbon, pre dark combined inside test-tube rooting and inside test-tube under lighting.(8) Under the subculture medium WPM+ZT 0.5 mg/L, the Test-tube Seedlings of Brigitta cultivate can be amplification as well as Sharpblue cultivate under AN+ZT 0.5 mg/L. (9) Plantlets 80-90% adapted well to the open environment, which meet completely the requirement of highbush blueberry tissue culture.(10) Different concentration of GA3 were used to improve the seed germination after the cooling disposed, and the regression equation of the seed germination rate was established as:G=0.085(GA3)-0.000034(GA3)2-0.805(Cv.)+7.666, the correlation coefficient R2=0.916, the predicted optimal concentration of GA3 is 1250mg/L.