Elementary Reserch On Distant Grafting In Vitro And ISSR Analysis Of The Grafting Plants

Grafting has beening widely applied to agriculture,forestry and horticulture,and micrografting based on tissue culture are used as an important tool for production and science research.It is being regarded as important that to improve plants' traits by distant grafting since the breeding specialist, Meng-Zhaohuang,succeeded in grafting mung bean onto sweet potato,and obtained a prolific,high quality new mung bean variety,which created great value.Further studies on the application of the distant grafting technique may contribute to a new way for plant breeding.The grafting plant was cultivated in manual manipulation condition,which excluded the effect of environmental agents,and makes the study much more convenient,therefore,micrografting is becoming an important tool in production and primary theory reaserch.Flowering plants involved in 11 families included grafting combinations of herb and wood, dicotyledon and monocotyl,different families,were the main materials in this study.By the method of micrografting,a serious experiments were carried out in an attempt to approach the influence on grafting of several factors.The main results showed as follow.The study on different grafting combinations indicated that combinations whose survival rates achieved 30%and above included Celosia cristata/Anthurium andraeanum(36.7%),Celosia cristata/Sinningia speciosa(33.3%),Kalanchoe blossfeldiana/Anthurium andraeanum(30.0%), Sinningia speciosa/Celosia cristata(30.0%);the combinations whose survival rates were 20%～30% included Kalanchoe blossfeldiana/Sinningia speciosa(26.7%),Kalanchoe blossfeldiana/Celosia cristata(23.4%),Sinningia speciosa/Kalanchoe blossfeldiana(20.0%),Sinningia speciosa/Anthurium andraeanum(20.0%);the combinations whose suvival rates were 10%～20%included Celosia cristata/Kalanchoe blossfeldiana(16.7%),Celosia cristata/Crassulaceae Sedum(16.7%),Lilium brownii/Kalanchoe blossfeldiana(15.0%),Oenothera erythrosepala/Sinningia speciosa(13.3%), Kalanchoe blossfeldiana/Crassulaceae Sedum(13.3%),Zantedeschia eathiopica/Celosia cristata (10.0%),Kalanchoe blossfeldiana/Stachys arrecta(10.0%);the combinations whose suevival rates were below 10%included Zantedeschia eathiopica/Sinningia speciosa(6.7%),Sinningia speciosa/ Stachys arrecta(6.7%),Catharanthus roseus/Celosia cristata(6.7%),Lilium brownii/Celosia cristata(5.0%),Oenothera erythrosepala/Celosia cristata(3.3%);and none survival grafting plants was obtained in the other combinations.There was no survival grafting plant came from conbinations of herb and wood.The survival rate of combinations of dicotyledon and monocotyl,family and family,were respectively 10.9%and 13.9%.The method of grafting has a certain influence on grafting survival rate.To Kalanchoe blossfeldiana/Celosia cristata,by method C,the rate was 27.5%,which is the top of the three.And it made significant difference contrasted with the other two methods.Age of the stock and scion is one of the crucial factors for a successful grafting.Source of scion and stock in proper age should be choosed according to different plant.Celosia cristata L.cultured in vitro and seeding plant of 10 d grafted onto Sinningia speciosa were the most suitable,and the survival rate were respectively 30%and 35%;as stocks,Celosia cristata L.cultured in vitro of 20ds and seeding plant of 25 d were better to be grafted in Kalanchoe blossfeldiana,and their survival rate were 27.5%and 32.5%.And there was little difference between tissue culture plant and seeding plant.Size of stem apex cut as scion is also an important factor for a successful grafting.To Kalanchoe blossfeldiana/Sinningia speciosa,stem apex of 6 mm got the highest survival rate,30.%. Larger or smaller size both do harm to micrografting.To remain some stock leaves benefits to micrografting.In this experiment,the survival rate of Oenothera erythrosepala/Sinningia speciosa reached 22.5%when using stocks with leaves,which was far higher than using stocks without leaves.In this experiment,scions were grafted in Anthurium andraeanum callus first time.Celosia cristata was grafted in Anthurium andraeanum callus,the survival rate was 27.5%,and the result made it clear that it was much higher than using tissue culture plants as stocks.ISSR analysis indicated that significant difference between the variation and the source of scion as well as stock was recognized in 7 combinations.2 of them may support the possibility that gene's transformation from stock to scion as traditional studies presumed for that a few PCR fragments amplified from the variety corresponded to those amplified from the stock.The genetic variation seems not to be caused simply by DNA transformation,since there is so far no cellular or molecular evidence revealing the possibility or exact mechanism of long distance movement of DNA.And transposition in response to environmental stress may also contribute to distant grafting-induced genetic diversity.