简介：ThenewspreadingconchosporesotPorphyrayezoensis,P.haitanensisandP.katadaivar.hemiphyllaareinducedbyN-Methy-N'-Nitro-N-Nitrosoguanidine(NG),astrongmutagentoinducethemutantofchromatophore.Itisshowedthat(1)nomutantshavebeeninvestigatedinallcontrolgroup.(2)TheconchosporesofallthethreespeciesofPorphyraareeasytobeinducedbyNGfortheyareinthestageofbreeding,Inthelowestdose(10μg/mL)ofthisexperiment,themutantrateofP.yezoensisisupto57.9%,thatofP.haitanensis30.7%andthatofP.katadaivar.hemiphylla51.7%.(3)Themutantratecannotincreaseobviouslybyincreasingthereagentconcentrationorprolongingtheinductiontime.Withinthescopeofexperiment,theinducementeffectsofthreespeciesofPorphyraaremuchsimilar,andthemutantrateisnear50%.TheoptimuminductionconcentrationofNGis10μg/mL,andtheoptimuminductiontimeis30minutes.

简介：AneuploidyembryosofPinctadamartensiiDunkerareproducedduringtetraploidinductionbyinhibitingthefirstpolarbodyineggsfromtriploidfertilizedwithhaploidspermswithcytochalasinBtreatment.Chromosomeanalysisrevealsthatthereare88.18±6.79%aneuploidyembryos,and28.70%aneuploidsinpearloystersofone-yearageTheseaneuploidshavefivechromosomalconditions,suchas2n+1(29),2n+2(30),3n-2(40),3n-1(41)and3n+1(43).Resultsofgrowthmeasurementshowthatthereisnosignificantdifferencebetweenaneuploids(asagroup)anddiploidsinbodysizeandweight(p＞0.10),buttheaneuploideisobviouslydifferentfromtriploid(p＜0.01).Themeanbodysizeandweightofaneuploidsindiploidcondition(2n±1and2n±2)aresignificantlysmallerthanthoseofdiploids(p＜0.01),butaneuploidswithintriploidcondition(3n±1and3n±2)arenotsmallerthandiploidsinbodysizeandweight(p＞0.1).ThisstudyindicatesPinctadamartensiiDunkercouldtolerateaneuploidyby7～14%ofthehaploidgenome,andthataneuploidsofthisspeciesareviableundercertainconditions.

简介：TheyoungthalliofPorphyrayezoensisandP.haitanensisareinducedbyN-Methy-N'-Nitro-N-Nitrosoguanidine(NG),astrongmutagentoinducethemutantofchromatophore.Itisshowedthatnomutantshavebeeninvestigatedinallcontrolgroups,whileintheinducedgroups,itiseasytofindmutantcellsormutantcellmassesinthethallus.ThepigmentationmutantsmaybetheresultofNGinducement.Themutantrateincreasesobviouslywiththemutagenconcentrationorbyprolongingtheinductiontime.Withinthescopeofexperiment,theinducementeffectsofPorphyrayezoensisareraisedfrom11.2%to28.7%,andthoseofP.haitanensisfrom10.1%to20.2%.Accordingtoourexperiments,theamountofmutantcellsinthesameareadoesnotincreasewiththeinductionintensityTheamountofmutantcellsineverygroupofinducementofbothspeciesofPorphyrachangesverylittlewiththefixedfieldscheckmethod.Thelowestdose(25μg/mL)ofthisexperimenthasahighmutantrate.Themutantrateshowsthepercentageofmutantcellsinallthesurvivedcells,whiletheamountofmutantcellsreflectstheeffectofinducement.ThustheoptimuminductionconcentrationofNGis25μg/mL,andtheoptimuminductiontimeis30minutes.