Studies On The Genetic Diversity Of Potato Germplasm

In this research, the genetic diversity of 62 potato germplasms werestudied on the morphological characteristics and the differences ofgerm- plasm by using morphological marker and AFLP (Amplified FragmentLength Polymorthisphism) molecular marker technique. The major resultsare summarized.1 Studies on the Primary Characteristics of Potato Germplasm(1) The morphological characters of 62 potato germplasms weredetermined and analyzed. The results indicated that the stems, leaves,flowers and tubers contained abundant genetic diversity in morphologicalcharacters(2) It had 19 potato germplasms which were more suit withautochthonic climates, early or very early, good tubers and high yieldof individual plant among the 62 potato germplasms, which could be madeuse of seed selection or breeding resources(3)The adaptability of some potato germplasms introduced into fromRussia and any other domestic areas were better than Canada.(4)The autumn characteristics of 62 potato germplasms were roughlydifferentiated by clustering fig according to the morphologicalcharacteristics, which reflected the differences of gene roughly.(5) The potatoes from different regions didn't cluster into the samegroup by using morphological marker clustering, and could not reflectedthe effects of origin environments upon genetic differentiations.(6) It maybe appeared warps when the seeding stage of potato germplasmswere identified by using morphological marker clustering, so the resultsonly could be regard as the references of by using AFLP molecular markertechnique on confirming seeding stage. 2 AFLP Analysis of Potato Germplasm(1)The qualities of potato DNA by using CTAB subarea method weredependable. After sufficient EcoR I/Mse I digesting reaction and ligationreaction, the DNA fragments length of pre-amplification centralizedbetween 100bp and 1000bp, and the length of high light strips distributedbetween 250bp and 500bp that were adapted to AFLP analysis.(2)9 pairs of primers E-AAG/M-CTG;E-ACA/M-CTG;E-ACA/M-CTA;E-ACT/M-CAG;E-ACT/M-CTA;E-ACT/M-CTGE-ACT/M-CTT;E-ACG/M-CTG;E-ACG/M-CTTwere screened out from 64 pairs of primers. When they were used for AFLPanalysis of 62 potato germplasms, it could all obtain relative higherdifferentiation rate DNA fingerprints.(3)In all 1440 AFLP markers, 1045 AFLP markers showed polymorphicamong three colonies that came from different areas with differentenvironments, so these 62 potato germplasms were provided with abundantgenetic diversity whether in total colonies or in small colonies thatpartitioned according to the different origins.(4) The AFLP clustering fig showed that 62 potato germplasms weredivided into three groups, which roughly accorded with the originalregions. Based on the analysis of genetic interval and genetic similaritycoefficient, it showed that potato germplasms's seeding stage came fromour country were close to Russian, but when they were respective comparedwith Canadian, the seeding stage were more distant.(5) The genetic similarity coefficient between 62 potato germplasmsdistributed between 0.6035 and 0.8650, which belonged to S.stuberosumssp. tuberosum in taxonomic status, but the genetic interval between someunits were relative distant, maybe, people had used some potato germplasmswith more distant seeding stage.(6) This research distinguished the seeding stage between 62 potatogermplasms, and the results can be used for the selection of parents inpotato breeding.