马铃薯块茎发育机理的研究

匍匐茎发生、块茎膨大和淀粉积累是马铃薯块茎发育的三个重要过程。由腋芽发生形成匍匐茎，主要进行细胞的分裂和纵向伸长，匍匐茎纵向伸长停止后，其顶端细胞的膨大是块茎膨大的主要原因，块茎形成过程中，伴随着淀粉的积累，这些过程均受激素、矿质营养、环境条件等不同因素的控制     

马铃薯块茎发育机理的研究

匍匐茎发生、块茎膨大和淀粉积累是马铃薯块茎发育的三个重要过程，由腋芽发生形成匍匐茎，主要进行细胞的分裂和纵向伸长，匍匐茎纵向伸长停止后，其顶端细胞的膨大是块茎膨大的主要原因，块茎形成过程中，伴随着淀粉的积累，这些过程均受激素，矿质营养、环境条件等不同因素的控制。     

马铃薯休眠块茎上芽眼组织休眠机理研究

以早熟品种中薯 3号和加工品种大西洋脱毒试管薯为试验材料 ,通过对休眠块茎芽薯分离培养 ,研究休眠块茎上芽离体培养后的生长发育变化。初步结果表明 ,休眠马铃薯块茎上侧芽停止生长始于匍匐茎生长期 ,主要受顶端优势的影响 ;顶芽停止生长开始于块茎形成起始 ,可能是因为匍匐茎上的细胞分裂中心和代谢重心转移影响 ;在块茎休眠过程中顶芽和侧芽不生长主要是受到来自块茎内部因素的抑制 ;当芽从休眠块茎上分离出来 ,在培养基上能够很快的生长。马铃薯块茎休眠和块茎上芽的休眠可能是两种不同的生理机制所控制。     

不同品种（系）马铃薯休眠块茎顶端和茎端芽眼组织马铃薯Y病毒含量分析

马铃薯Y病毒（Potato virus Y,PVY）是马铃薯生产中较常见的病毒之一,马铃薯病毒的检测是生产中保障马铃薯品质和产量的重要基础,收获后批量检测是进行种薯质量评价的主要依据之一。研究针对‘56-2’‘Ivory Russet’‘Clearwater Russet‘’龙薯14号‘’龙薯3号‘’龙薯15号‘’龙育201401-70‘’龙薯7号‘’克新23号’和‘克新28号’马铃薯品种（系）休眠块茎样品,采用TRIzol法提取马铃薯休眠块茎顶端和茎端芽眼组织的总RNA,经qRT-PCR和RT-PCR检测分析,比较块茎的顶端与茎端芽眼组织PVY含量分布的情况。结果表明,上述供试材料的休眠块茎茎端芽眼组织PVY浓度均高于顶端芽眼组织,能够精准的检测到病毒的存在;对‘Ivory Russet’品种的休眠块茎选取100个带病样品通过TRIzol法提取顶端与茎端的总RNA,采用4合1的方法合样后进行PVY RT-PCR检测,所有处理的顶端芽眼组织检测条带亮度低于茎端芽眼组织。可见,马铃薯休眠块茎茎端芽眼组织取样能够更加精准的检测出PVY。研究结果为马铃薯种薯收获后PVY的检测及合理取样提供了...     

氮素形态与马铃薯品质的关系

在田间条件下研究了不同形态氮素对马铃薯块茎硝酸盐含量、淀粉、蛋白质及还原糖含量的影响。结果表明,马铃薯块茎内硝酸盐含量从块茎形成期到成熟收获期是逐渐降低的。使用铵态氮肥并加硝化抑制剂双氰胺可以显著地抑制马铃薯块茎硝酸盐的积累;与硝酸盐含量变化相似,从块茎形成期到收获期蛋白质含量也逐渐降低,不同氮素形态处理对马铃薯块茎内蛋白质含量的影响无显著差异;铵态氮添加双氰胺处理可降低块茎还原糖含量。虽然马铃薯被认为是喜硝作物,但本研究表明,不同氮素形态处理不仅没有造成马铃薯产量的显著差异,而且块茎内淀粉含量也无显著差异。     

2.5%单氰氨诱导巨峰葡萄芽解除休眠的生理效应

以巨峰葡萄(Kyoho grapevine)为材料,用单氰氨对其休眠芽进行催芽试验,并分析休眠解除过程中芽的内源激素、淀粉、可溶性糖含量及淀粉酶活性的变化.结果表明:2.5%单氰氨处理能解除巨峰葡萄芽的休眠;2.5%单氰氨处理使休眠芽内GA3和ZR含量升高,IAA、ABA含量不断降低,淀粉酶活性加强,从而促进淀粉加速降解为可溶性糖.推测内激源素水平及代谢变化可能是单氰氨解除巨峰葡萄芽的休眠的关键因素之一.     

赤霉素解除马铃薯块茎休眠的调控敏感位点初探

以马铃薯栽培品种“大西洋”和“中薯 3号”脱毒试管薯为试验材料。以针沾取GA3处理休眠期试管块茎不同部位 ,研究GA3 解除马铃薯块茎休眠的调控部位。结果表明 :块茎顶部对GA3 处理最敏感 ,其次是基部 ,然后是第一侧芽、第二侧芽 ,说明GA3 解除块茎休眠过程中的敏感调控部位主要是在块茎的顶部     

马铃薯块茎休眠及其打破的方法

马铃薯块茎借休眠以渡过不利其生长的条件,从而保证世代繁衍的遗传特性。马铃薯块茎的大小和休眠时间的长短影响其商品价值和利用时间,储藏过程中的休眠解除会造成水分、养分大量消耗,以至丧失应用价值。随着生产发展的需要,有关马铃薯休眠的研究已经被提出,了解休眠特征和打破休眠的方法,对于栽培和储藏保鲜具有十分重要的意义。     

生长调节剂在马铃薯栽培中的应用

化学生长调节剂常用来加速马铃薯块茎发芽,也可用来减少马铃薯长期贮藏期间的损耗。现已查明,块茎的发芽势同其中的生长物质有密切关系。生长物质含量增高,发芽势随之增强。块茎顶部生长物质含量最高,主要又集中在芽眼分布的部位。块茎萌动过程中,顶部芽眼的生长物质含量进一步提高,从而保证了增加对芽眼的水分     

马铃薯块茎不同部位芽对掰芽繁殖的影响

掰芽技术是根据马铃薯具有多个芽眼的特点,充分调动每个芽眼发出苗进行掰芽移栽,达到快速繁殖,节约种薯,提高繁殖系数的目的。通过马铃薯的掰芽快速繁育试验,在试验中对马铃薯块茎上的芽按照不同的分布部位进行掰芽移栽。根据不同部位芽生长动态及其在掰芽繁殖中的成活率得出以下结论:薯顶的成活率达到100%,薯中的达到95.00%,薯尾的则只有84.72%。     

Physiological regulation of potato tuber dormancy

At harvest, potato (Solanum tuberosum L.) tubers are dormant and will not sprout. As the period of postharvest storage is extended, tuber dormancy is broken and sprout growth commences. The loss of tuber dormancy and onset of sprout growth is accompanied by numerous biochemical changes, many of which are detrimental to the nutritional and processing qualities of potatoes. Endogenous hormones have been proposed to play a significant role in tuber dormancy regulation. The involvement of all major classes of endogenous hormones in tuber dormancy is reviewed. Based on available evidence, it is concluded that both ABA and ethylene are required for dormancy induction, but only ABA is needed to maintain bud dormancy. An increase in cytokinin sensitivity and content appear to be the principal factors leading to the loss of dormancy. Changes in endogenous IAA and GA content appear to be more closely related to the regulation of subsequent sprout growth.     

Is dormancy breaking of potato tubers the reverse of tuber initiation?

Summary Tuber formation is a well orchestrated physiological event that involves many metabolic changes. Dormancy gradually develops in potato tubers from the moment cell division in the stolon tip has stopped and the tuber starts to develop. Dormancy breakage may be the reverse of dormancy initiation suggesting that there may be similarities between tuber induction and dormancy development. Based on a literature review it is concluded that, when comparing tuber induction and the breaking of dormancy, hormonal activities are only partly reversed, whereas carbohydrates and enzyme activities might be reversed. For more definite conclusions more research should be done to assess precisely the moment of dormancy breaking. Moreover, measurements on events associated with tuber induction and dormancy breaking should be carried out using the same techniques and the same material. Molecular genetic analyses may provide well-defined markers for the timing of breaking of dormancy.     

马铃薯高淀粉生理基础的研究——块茎组织结构与淀粉积累的关系

马铃薯块茎以皮层区的淀粉含量最高,环髓次之,内髓最少,但环髓区的淀粉在整个块茎中所占的比重最大,淀粉含量指数也最高;内髓区的淀粉在块茎中占的比重最小,淀粉含量指数也最低.皮层区的淀粉含量高低、皮层的厚度、环髓区的淀粉含量指数与块茎淀粉含量呈显著的正相关、皮层区、环髓区、内髓区的细胞大小、输导系统的筛管和导管面积,随块茎的增大和淀粉的积累而增大,其中除皮层区细胞大小与块茎淀粉含量呈负相关之外,其余各组织的细胞大小与块茎淀粉含量没有明显的相关性.     

马铃薯种薯芽条生育规律的研究

种薯萌发的芽条数不随萌芽时间的延长而增多,但在高温(22～28℃)下萌芽和种薯尚未完全通过休眠时催芽,会使萌芽数显著减少。品种、光照、温度、萌芽时间、赤霉素浸种等因素条件的不同,对芽条伸长速率和芽生长锥分化程度和速率有显著影响、而对芽条节间数、生根节数、顶芽萌发数的影响不明显。芽条根原基只有在黑暗潮湿的条件下才能仲长,以芽条基部1～3节的根系发生最早、最多、早长。芽生长锥分化程度与芽条其它各器官的发育程度呈显著正相关,它是衡量芽条发育水平的最具代表指标。     

小麦铭贤169休眠解除期间种子结构与主要成分的变化

为探究小麦种子休眠解除期间的成分变化对发芽率的影响,了解种子休眠解除机制,以铭贤169为材料,在收获后不同储藏时间(间隔20 d)取样,通过显微设备观察了种子后熟期间的结构变化,测定了相关生理指标和成分,以探究铭贤169种子休眠性原因。结果表明,铭贤169种子休眠解除过程中,种皮细胞结构、组织结构、淀粉粒结构、蛋白基质等均发生变化,淀粉含量、粒径、糊化特性、热稳定性随贮藏时间延长变化显著。铭贤169的离体胚在花后25 d就具有发芽能力,但种子在花后35 d仍处于休眠。收获后熟期间,种胚活性、种子吸水率、含水量、淀粉含量、淀粉糊化谷值粘度和峰值时间、热稳定性逐步上升,与发芽率正相关。A型淀粉粒表面破损,淀粉粒与蛋白质结合紧密,种皮结构松散;淀粉粒径、淀粉酶活性、可溶性糖含量和沉降值减小;面筋和粗蛋白含量变化不大。推测铭贤169种子的休眠性与种子母体成分有关,休眠解除期间发芽率变化受种皮结构、淀粉的分解程度、淀粉粒与蛋白质的结合方式、可溶性糖含量、淀粉含量和性质以及淀粉酶活性等因素影响。     

锦绣杜鹃花芽分化与叶片物质变化的相关性研究

观察锦绣杜鹃的花芽分化结构变化,测定来自不同开花率的植株叶片中蛋白质、可溶性糖、淀粉和叶绿素含量,初步探讨这些物质变化与其花芽分化过程的相关性。结果表明:广州地区的锦绣杜鹃在6月下旬开始花芽形态分化,约40 d形成完整的小花结构,8月中下旬出现肉眼可见花蕾。锦绣杜鹃在花芽分化过程中,高成花率植株的功能叶中干物质含量趋于稳定。蛋白质含量出现升高-降低-升高-降低的起伏变化,直至花芽分化完成后再一直回升趋于平稳;可溶性糖、叶绿素含量均呈升高-降低-再回升的变化趋势;淀粉含量呈降低-升高-降低-再回升的变化。蛋白质、可溶性糖、淀粉和叶绿素在花芽分化前的快速有效积累和后期的有效利用,对锦绣杜鹃花芽分化具有非常重要的作用,并与植株成花率有一定的关系。     

Protein,starch, and non-protein nitrogen accumulation in high protein hybrids and low protein cultivars

Tuber protein, starch, non-protein nitrogen and percent dry matter content were measured during tuber development of four Phureja-Tuberosum-Andigena hybrids and two Tuberosum cultivars. Percentages of starch and protein in the tuber dry matter were curvilinearly related to tuber size in all six clones. The amounts of starch and protein in a tuber were linear functions of tuber size. Rates of protein accumulation in some of the hybrids were higher than those of either cultivar. Starch accumulation rates were similar among all six clones. The high protein character of at least one of the hybrids was associated with starch containing storage tissue. Differences between high and low protein clones were mainly related to quantitative differences in the subunit composition of the protein. The ratio of non-protein nitrogen to protein N was similar among the six clones. Relationships between percent dry matter and starch content were not consistent among the six clones.     

Dormancy release in potato tubers: A review

Dormancy release in potato tubers is reviewed in the context of recent biochemical and physiological research with particular emphasis on describing ambiguities in the literature. A complex picture of dormancy release emerges with hypothetical multiple roles for most major plant growth regulator groups which occur within the tuber. Current literature continues to support the “inhibitor/promoter” hypothesis with the critical events associated with dormancy release involving a shift in the growth regulator ratio in favor of promoters and subsequent establishment of positive feedback between the bud and the mobilized food reserves. Dormancy release by external chemical agents possesses immediate practical applications such as dormancy breaking of seed tubers for export or local use, incorporation into seed multiplication programs and rapid post-harvest disease testing procedures. In addition, research using these chemical agents as experimental probes should prove useful in exploring the control mechanisms associated with dormancy release.