果梅果实发育过程中有机酸含量及相关代谢酶活性的变化特征.pdfVIP

果梅果实发育过程中有机酸含量及相关代谢酶活性的变化特征

刘雅兰;靳志飞;陈红

【摘要】以优选荔波野生梅单株荔波-3和荔波-11为试验材料,采用高效液相色

谱法(HPLC)测定了果梅果实在发育过程中有机酸含量及相关代谢酶活性变化特征.

结果表明:(1)荔波-3和荔波-11果梅果实中柠檬酸和苹果酸主要在果实发育后期

积累,花后140d两品种的柠檬酸积累量达到最大,且果实中总酸的积累量也相应的

达到最大值.(2)柠檬酸积累量与柠檬酸合成酶(CS)活性呈极显著正相关关系,荔波-

11因CS活性高于荔波-3,使得其果实成熟时的柠檬酸含量高于后者.(3)苹果酸积

累量与磷酸烯醇式丙酮酸羧化酶(PEPC)和NAD-苹果酸脱氢酶(NAD-MDH)活性呈

极显著正相关关系,但与NADP-苹果酸酶(NADP-ME)活性呈负相关关系;在花后

45~100d内,果梅果实中PEPC和NAD-MDH活性迅速升高,而NADP-ME活性

相对较低,使苹果酸积累量迅速增加;在花后120~140d,荔波-3果实中PEPC、

NADP-MDH活性显著高于荔波-11,而其NADP-ME活性低于荔波-11,导致成

熟时荔波-11的苹果酸含量高于荔波-3.可见,果梅果实的有机酸主要在果实发育

后期积累,有机酸积累差异受多个酶协同调控;苹果酸的积累差异主要由NAD-MDH、

PEPC和NADP-ME活性协同变化引起,柠檬酸积累差异主要受CS活性变化影

响.%TakingtheoptimizingplantLibo-3andLibo-11Prunusmumewhich

wasnativetoGuizhouProvinceasmaterials,usingthemethodofultra

performanceliquidchromatograph(UPLC),wemeasuredthechangesof

organicacidcontentsandrelativemetabolicenzymeactivitiesduringthe

developmentofPrunusmumefruit.Theresultsshowedthat:(1)citricacid

andmalicacidofLibo-3andLibo-11main-lyaccumulatedinthelate

periodoffruitdevelopment,afteranthesistheaccumulationofcitricacid

reachedthemaximumat140d,theamountoftotalacidinthefruitalso

accordinglyreachedthemaximumvalue.(2)Theaccumulationofcitricacid

wasrelatedtotheactivityofcitratesynthase(CS),thecontentofcitricacid

ofLibo-11washigherthanthatofLibo-3sinceforitsCSactivitywas

higherattheripeningnbsp;stage.(3)Thecontentofmalicacidexhibited

positivecorrelationwiththeactivitiesofPEPCandNAD-MDH,whilethe

NADP-MEactivityexhibitednegativecorrelation.Thedifferenceinmalic

acidaccumula-tionismainlycausedbythecoordinationchangeof

PEPC,NAD-MDHandNADP-MEactivities.Afteran-thesis45to100d,the

activitiesofPEPCandNAD-MDHincreasedrapidly,whiletheNADP-ME

activity