【作者】 康朵兰；

【导师】 肖浪涛；

【作者基本信息】 湖南农业大学 ， 植物学， 2007， 硕士

【摘要】 马铃薯是世界第四大粮食作物。由于马铃薯在常温下贮藏易发芽而失去食用价值，在生产上一般采用低温贮藏，但低温贮藏会造成还原糖的增加而降低加工品质。因此，如何调控马铃薯块茎的休眠与萌发，解决低温糖化等问题，是当前马铃薯产业中急需解决的问题。本研究以加工型马铃薯品种大西洋为试材，比较了从休眠到萌发过程中马铃薯块茎顶芽等组织与块茎其余组织的植物激素和多胺含量差异；分析了块茎中淀粉、可溶性糖和蛋白质含量的变化动态，测定了相关酶活性等生理生化变化；研究了不同保鲜措施对低温糖化的影响，获得如下主要研究结果：1在马铃薯收获40 d后其块茎顶芽组织中GA₁、GA₃、GA₄、IAA、Z、ABA含量高于块茎其余组织，且两者变化趋势也不一样。块茎顶芽组织中GA₁、GA₄含量在0-40 d时下降，40 d以后开始增加；GA₃在20 d以后呈上升趋势；IAA和Z从40 d开始增加；ABA在0-55 d减少，然后增加。而块茎其余组织中植物激素变化与块茎顶芽组织的不同之处为GA₄在0-55 d下降，55 d后开始增加；IAA在0-55 d减少，然后增加；Z含量变化不显著。同时还发现马铃薯萌发前后赤霉素的组成也有所不同，在萌发前，块茎顶芽组织和块茎其余组织中赤霉素以GA₄为主，在萌发过程中块茎顶芽组织和块茎其余组织中GA₄上升幅度大，表明GA₄对解除休眠有重要作用；而在萌发后15 d的芽中则以GA₁为主，说明GA₁对萌发后芽的生长起重要作用。2马铃薯块茎其余组织中腐胺和亚精胺在收获后55 d到萌发时含量下降，而精胺含量在收获后55 d开始上升，至萌发时，含量增加了2倍。而顶芽组织在从收获后70 d到萌发过程3种多胺含量都增加，并且在芽中出现高峰，芽中多胺含量与收获后70 d的顶芽组织中的多胺进行比较，芽中腐胺含量增加了1倍，亚精胺的含量增加了1.5倍，而精胺的含量增加了8倍多。外施3种外源多胺对马铃薯收获后的休眠期没有明显影响，但都可以促进萌发后芽的伸长生长与加粗。3马铃薯块茎在休眠到萌发的过程中，淀粉含量逐渐下降，可溶性糖含量逐步上升，可溶性蛋白和醇溶性蛋白含量开始时变化不明显，在收获后40 d时出现高峰，淀粉酶、淀粉磷酸化酶活性分别在收获后40 d和50 d时上升，而多酚氧化酶活性则在收获后50 d时降低。外施GA₃能提高淀粉酶和淀粉磷酸化酶的活性，降低多酚氧化酶的活性，促进淀粉的降解和可溶性糖含量的增加，从而促进马铃薯的萌发。4通过低温贮藏保鲜与低温糖化控制研究，筛选优化了低温贮藏保鲜方案，发现“0.06％磷酸钠+1％壳聚糖+1％柠檬酸”调节剂和“0.02％水杨酸+1％壳聚糖+1％柠檬酸”调节剂能有效抑制低温贮藏时马铃薯块茎还原糖含量的增加，减少淀粉含量的下降，提高贮藏品质。更多还原

【Abstract】 Potato （Solanum tuberosum L.） is the fourth staple food crop in the world, butunder room temperature potato tuber sprouts rapidly, which makes it unable to eat.The harvested tubers of potato are normally stored at low temperature to preventsprouting. But the increased reducing sugars （RS） caused the decrease of qualityduring low temperature storage. Therefor, the regulation of potato tuber dormancyand sprouting, as well as low temperature sweetening are key problems to be resolvedin potato production.This study takes the processing potato variety Atlantic as material, compared thecontents of endogenous phytohormones and polyamine of the apcial bud region oftuber and other regions of tuber, studied the changes of starch, soluble sugars andprotein, detected the activity changes of related enzymes and studied the effects onlow temperature sweetening under different storage measures. The results are asfollows:1 The contents of GA₁, GA₃, GA₄, IAA, Z and ABA in the apcial bud region oftuber were higher than those in other regions of tuber 40 days after harvesting（DAH）.The change trends of the above phytohormones in both regions were alsodifferent. The contents of GA₁ and GA₄ decreased at 20 DAH and 40 DAH, and beganto increase after 40 DAH; the content of GA₃ began to increase at 20 DAH, thecontents of IAA and Z began to increase at 40 DAH; the content of ABA decreasedfrom 20 DAH to 55 DAH, and increased after 55 DAH. The changes ofphytohormones content in other regions of tuber had some differences with the apcialbud region of tuber. The content of GA₄ reduced from 20 DAH to 55 DAH, andincreased from 70 DAH to 85 DAH; the content of IAA reduced from 20 DAH to 55DAH, and slowly increased from 70 DAH to 85 DAH; the changes of Z content wasnot significant. The GA₄ was the major gibberellin in the apcial bud region of tuberand in other regions of tuber before sprouting, in the sproouting process, the GA₄content increased significantly in the apical bud region of tuber and in other regions oftuber, which indicated GA₄ plays an important role to break dormancy; while the GA₁content is the major gibberellin in the bud of after sprouting, which indicated GA₁plays an important role to bud growth.2 The putrescine and the spermidine contents decreased in other regions of tuberfrom 55 DAH to sprouting, the spermine content increased from 55 DAH to sprouting. But all the three polyamines contents in the apical bud region of tuberincreased from 70 DAH to sprouting, and the bud has the highest contents. At 70DAH, the putrescine content increased 1 time, the spermidine content increased 1.5times and the spermine content increased about 8 times. Exogenous polyaminesapplication showed that the exogenous polyamines had no obvious effect on potatodormancy, but promoted bud elongation growth and stem widening growth.3 From dormancy to sprouting, the starch content decreased gradually, and thesoluble sugars content increased gradually. Water soluble and alcohol soluble proteinhad a raise during later storge, and reached a highest content from 40 DAH. Theamylase activity increased from 40 DAH, amylophosphorylase activity increasedfrom 50 DAH, while the polyphenol oxidase activity decreased from 50 DAH. Theexogenous GA₃ increased the amylase and amylophosphorylase activities, speeded upthe starch decomposition and increased the soluble sugar content during the tuberstorge, and at the same time the exogenous GA₃ decreased the polyphenold oxidaseactivity, resulting in speeding up of potato sprouting.4 Fresh-keeping methods at the low temperature were studied and theoptimization measures to reduce the RS content during low temperature storage werescreened. The results showed that the formulation" 0.06% sodium phosphate+1% citricacid +1% chitosan" and formulation " 0.02% salicylic acid+1% citric acid +1%chitosan" decreased the RS content and increased the starch content during lowtemperature storage, which improved the storage quality of potato.更多还原