Aflp Analysis Of Genetic Background Of Mulberry Polyploid Breeding Materials

Mulberry artificial triploid breeding is becoming the focus in mulberry breeding because the economic characters and the agronomic characters of artificial triploid mulberry are excellent than that of diploid mulberry and natural triploid mulberry. Genetic background of 19 materials used for artificial triploid breeding, which including 14 tetraploid materials and 5 diploid rnatercials, are analyzed by the AFLP (Amplified Fragment Length Polymorphism) from which the fingerprint and the UPGNIA dendrogram of the materials are abtained . According to the results, if the genetic coefficient between diploid material and tetraploid material is less than 0.7500. which is the identification of mulberry species according to the former study and this study, the two materials can be used for hibridization .16 hibrid combinations selected from 19 assayed materials can be used for mulberry artificial triploid breeding. The genetic diversity between diploid and homologous tetraploid chemically induced by colchicines are analyzed. The result indicates that the genetic diversity between diploid and homologous tetraploid is less than that of interspecies, more than that of?individuals, at the level of? intraspecies. It can be conclLtded that the DNA molecular sequence of homologous tctraploid materials changes compares with diploid according to the results. As to the study in which AFLP and RAPD are used for mulberry research, the results by two means are consistant when the bloodrelationship of materials is close, AFLP is more appropriate to materials whose bloodreltionship is close through comparison and analyzation. A means is explored through which high quality DNA are extracted, that is CTAB buffer plus I 3~ PVP. with the method of phenol-chloroform-isopentamol-endoribonucleases. The protein and RNA are eliminated completely. and it is found that PVP has the function to eliminate polyhexose. The DNA extracted is fit for AFLP.