| Kenaf (Hibiscus cannabinus) is an important fiber crop. By now ,the genetic map of kenaf has not been reported. Using SRAP , ISSR and RAPD marks we constructed the first genetic linkage map in kenaf. The major results are as follow:1) .Construction of mapping colony: In foundation of ISSR and SRAP molecule markscluster analysis of 84 genetic diversity and genetic relatoinship of 84 kenaf germplasm resource in the world, we constructed mapping colony-155 F2 individuals from the cross of two kenaf: semi -wild species Ga42 (from gana) and cultivated species A Lian kenaf (from Egypt).2) .Screening of biasc polymorphism primers: From the kenaf genome , 27 SRAP primer pairs and 25 ISSR primers and 6 RAPD primers, which could reveal poly-morphisms between Ga42 and A Lian kenaf, were screened out of 19X19 primer combinations of SRAP , 60 ISSR primers and 20 RAPD primers.3) .PCR amplification of the mapping colony: Using 27 SRAP primer pairs,31 ISSR and RAPD primers, we undertook the PCR amplification of the F2 mapping colony . These markers generated 208 polymorphic bands in the F2 population analysis. The average of polymorphic bands produced by one primer pair was 3.6, and the maximum was 8.4) .Construction of genetic linkage map: Using Mapmaker/3.0, a linkage map was constructed, which consisted of 65 SRAP markers, 56 ISSR markers and 13 RAPD makers distributed in 20 linkage groups (L0D≥3 0) and spanned 2108.9cM with an average interval of 18.5cM between markers. Each SRAP primer pair could generate 10-50 clear bands with a length range between 100 and 1000 bp and about 70% of bands showed strong signal. Among the 208 markers, 96 markers(46%) segregated aberrantly against the expected 3:1 ratio.5) .Analysis of partial segregation: As kenaf has 18 pairs of chromosomes, In the present study,the kenaf map includes 20 linkage groups, which may be attributed to small number of markers which caused that density of polymorphism sites were not high and distribution of sites were inhomogeneous.
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