Physical Locations And Analysis Of 16 Markers On The Sixth And Sixteenth Linkage Group Of Genetic Map In Hevea Brasiliensis

Hevea brasiliensis belongs to Euphorbiaceae rubber tree, is a perennial tropical tree. Latex is the main source of natural rubber which comes from the rubber tree, and it has a very important commercial value. A number of genetic maps of rubber trees have been constructed by different molecular markers, but the relationship between genetic map and chromosome is not clear. Fluorescence in situ hybridization (FISH)has been widely applied for cytogenetic development up to now, to integrating the physical map and genetic map? to building molecular cytogenetic map has great importantance for the correct assembly of the genome sequence and the direction of the chain and sequence stitching.In this study, Reyan 7-33-97 of Hevea brasiliensis was selected as experimental material, 16 RFLP markers on No. 6 and No. 16 linkage groups on the genetic map of Hevea brasiliensis constructed by Lespinasse in 2000 were marked in Reyan 7-33-97 of Hevea brasiliensis by fluorescence in situ hybridization and in situ PCR. We can determine the location of these markers through karyotyping in the chromosome and find the corresponding relationship between the linkage group and the chromosome.The results are as follows:(1) The 13 genetic markers on the linkage group No. 6 located on the 3rd chromosome of Reyan 7-33-97 of Hevea brasiliensis, the sequence of genetic markers on the linkage group is consistent with the order of position on the chromosome.Eight of them genetic markers (gHbCIR 477?gHbCIR689.L1?gHbCIR140?gHbCIR207?gHbCIR 121?gHbCIR523.L1?gHbCIR150?gHbCIR 528) were located on the short arm of chromosome 3, the signal point to the real grain percentage of the order of 56.55?37.59?33.16?28.78?21.51?17.79?15.67and 4.63, respectively. And other five genetic markers (gHbCIR475?gHbCIR129/489?gHbCIR647.L1?gHbCIR 396 and gHbCIR675) were located on the long arm of chromosome 3 with the order of28.02?30.96?51.04?53.69 and 66.34 respectively,the location of the pellets is between the genetic marker gHbCIR528 and the genetic marker gHbCIR475.(2) The 6 genetic markers (gHbCIR421?gHbCIR588?gHbCIR647.L2?gHbCIR130?gHbCIR523.L2 and gHbCIR689.L2) on the linkage group No. 16 marked on the 15rd chromosome of Reyan 7-33-97 of Hevea brasiliensis, the sequence of genetic markers on the linkage group is consistent with the order of position on the chromosome. gHbCIR421?gHbCIR588?gHbCIR647.L2 and gHbCIR130 were located on the short arm of chromosome 15, the signal point to the real grain percentage of the order of 27.96?18.98?15.40 and 12.56 respectively,the other markers were located on the long arm of chromosome 15, the signal point to the real grain percentage of the order of 43.13and 60.50 respectively. The location of the pellets is between the genetic marker gHbCIR130 and the genetic marker gHbCIR523.L2.(3 ) We can make a preliminary conclusion that the No. 6 linkage group of the genetic map corresponds with the No. 3 chromosom of Reyan 7-33-97 of Hevea brasiliensis and the No. 16 linkage group corresponds with the No. 15 chromosom by the results of physical positions.