Study On The Rootage Mechanism Of Rabbiteye Blueberry Cuttage

The origin of Rabbiteye blueberry(Vaccinium ashei) was North America,which subordinated to Vaccinium of Ericaceae,was suitable for planting in subtropical and tropical zone.The seedling production of Rabbiteye blueberry was mainly by means of cuttage at present.The difference of quicksets Callus-generated ratio were significantly between different breeds,different hormone treatments and different degree of lignifications,and those were the main factors that affected the seedling cuttage of Rabbiteye blueberry.In this paper the main factors which affecting cuttage of Rabbiteye blueberry were studied.The results were as fellow:1.The effects of low density exterior hormones treatments on cuttage of Rabbiteye blueberryThe difference of Callus-generated and rootage ratio among breeds of Powderblue,Gardenblue,Premier and S₁₃ were significantly,by treated the semi-lignified quicksets of four breeds with water only.The results show that quickset of breed Gardenblue was easiest for cuttage among four breeds whereas breed Powderblue and S₁₃ were most difficulty for cuttage.The results also indicated that the Callus-generated and footage ratio of the same breed there were significantly difference among different density hormone and different hormones treatments.For breed Powderblue,GGR treatment with density 50ppm was better for Callus-generated and rootage of quickset,the Callus-generated and rootage ratio increased 42.5%and 33.33%,compared with contrast.But for breed Gardenblue,the Callus-generated and rootage ratio of quickset there were no significantly difference between 50ppm GGR treatment and contrast.It was propitious for Callus-generated and rootage of breed Premier by treated the quickset with GGR at density 100ppm,and compared with the contrast,the Callus-generated and rootage ratio of quickset increased 10.8%and 7.5%.For breed S₁₃,25ppm GA treatment was best for quickset Callus-generated whereas 100ppm GGR treatment was best for quickset rootage among all treatments.2.Study on the dynamic changes of endogenous hormones of Rabbiteye blueberry quickset cortex in the cuttage processThe callus generating process were divided into three stages,Callus Inducement Phase(CIP) that was affirmed when the cut begin to expand,Callus Early Generation Phase(CEGP) that was confirmed when 25 percent of cut generated the white callus,and Callus Heavy Generation Phase(CHGP) that affirmed when 50 percent of cut generated callus,by observed the morphological change of cut of three breeds Powderblue,Premier and S₁₃ in the cuttage process. At Callus Heavy Generation Phase some cut start to root,so this phase also called Root Early Generation Phase(REGP).The dynamic changes of endogenous hormones of Rabbiteye blueberry breeds Powderblue,Premier and S₁₃ quickset cortex in the cuttage process were studied.The results show that the appearance time of fastigium and the maximal content of endogenous hormones IAA,ABA,GA and ZR were different significantly with different kinds of exterior hormones and different hormone density used.3.The effects of embedded substance of different degree lignifications on survive of quicksetsThe relativity between the content of embedded substance and the conservation ratio of different degree lignifications quicksets of breeds Powderblue,premier and S₁₃ were studied.There were significantly negative linear correlation between the conservation ratio of Powderblue quicksets and the content of total sugar, dissoluble sugar,endogenous hormones GA and ZR,and their correlation coefficient(r) were from 0.9983 to 0.9992.For breed premier,the relationship between quickset conservation ratio and the content of total sugar,endogenous hormones GA and ZR were significantly negative linear correlation,their correlation coefficient(r) were from 0.9989 to 1.0.The positive linear correlation were observed significantly between the quickset conservation ratio of breed S₁₃ and its content of dissoluble sugar,total nitrogen,total phenol,endogenous hormones GA and ZR.The significantly negative linear correlation also were observed between quickset conservation ratio of S₁₃.and its content of total sugar.4.The Role of Endogenous Hormones Fastigium Happened of Rabbiteye Blueberry Quickset under Optimal Exterior Hormone Treatment.The role of endogenous hormones IAA,ABA,GA and ZR fastigium happened of Rabbiteye blueberry quickset which treated with optimal exterior hormone for quickset Callus-generated and rootage were analyzed.The content fastigium of endogenous hormones IAA of all three Rabbiteye blueberry breeds appeared at CIP,it indicated that it benefit for generating callus of cut if the content fastigium of endogenous hormones IAA appeared within 35 days.The content fastigium of endogenous hormones ABA and GA of quickset appeared at CIP,CEGP and CHGP,if the content fastigium of endogenous hormones ABA and IAA of quickset which treated with exterior hormone appeared in-phase,the rootage rate of quickset was highest,but the content fastigium of endogenous hormones GA and IAA of quickset which treated with exterior hormone appeared in-phase,the rootage rate of quickset was lowest.The content fastigium of endogenous hormones ZR of all three Rabbiteye blueberry breeds quickset which treated with optimal exterior hormone for quickset Callus-generated and rootage happened at CEGP and CHGP,this phenomenon indicated that endogenous hormone ZR was propitious to the cleavage and growth of callus,and promoted roots generating consequently.