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首次报道了中国樱桃的花芽分化规律.中国樱桃中、短梢上花芽的形态分化开始期早,镜下观察最早出现在5月下旬;长梢上的花芽形态分化晚,可陆续分化到8月中旬.单个花芽分化过程历时约110d,中、短梢上花芽生理分化期在形态分化开始前1个月. 相似文献
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为给阿克苏地区制定合理的欧洲李栽培管理技术措施提供理论基础,以品种‘女神’、‘斯坦勒’和‘法兰西’为研究对象,通过常规石蜡切片法对其花芽内部生长点组织形态分化过程进行观察,探讨欧洲李在阿克苏地区的花芽分化进程。在6月26日第1次取样时,大多数的花芽已经处于始分化期。‘斯坦勒’的花芽在9月23日雌蕊分化基本完成,分化时间在90 d以上;‘女神’在10月20日基本完成雌蕊分化,分化时间大约在120 d。而‘法兰西’在10月20日只有60%的花芽雌蕊分化完成。欧洲李花芽分化进程可以分为未分化期、始分化期、花蕾原基分化期、花萼原基分化期、花瓣原基分化期、雄蕊原基分化期、雌蕊原基分化期7个分化时期。3个欧洲李品种花芽形态分化存在各时期重叠交错现象,各时期间没有明显的界限,均是逐步分化的,各品种花芽分化时期的形态特征大致相同,但是分化进程存在一定差异,‘斯坦勒’的雌蕊原基最先完成分化,其次是‘女神’,最后是‘法兰西’。 相似文献
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We investigated the influence of bud position, cultivar, tree age, tree carbohydrate status, sampling date, drought and light exposure on the number of leaf primordia formed in dormant vegetative peach buds (Prunus persica (L.) Batsch) relative to the number of primordia formed after bud break (neoformed). During winter dormancy, vegetative peach buds from California and Italy were dissected and the number of leaf primordia recorded. Between leaf drop and bud break, the number of leaf primordia doubled from about five to about 10. Parent shoot length, number of nodes on the parent shoot, cross-sectional area of the parent shoot, bud position along the parent shoot and bud cross-sectional area were correlated with the number of leaf primordia. Previous season light exposure, drought and tree carbohydrate status did not affect the number of leaf primordia present. The number of leaf primordia differed significantly among peach varieties and tree ages at leaf drop, but not at bud break. Our results indicate that neoformation accounted for all shoot growth beyond about 10 nodes. The predominance of neoformed shoot growth in peach allows this species great plasticity in its response to current-season conditions. 相似文献
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本文对三台核桃进行动态和定态观测，结果表明：牙于3月下旬开始分化，先后顺序是叶芽、雄花芽、混合芽；品种不同，顶（侧牙的抽生情况不同，其中结果母枝粗是影响顶（侧）芽抽生数的主要性状；雄花芽的抽生数大于混合芽的抽生数，雄花序开放至脱落历时16d左右。 相似文献
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采用常规石蜡切片法,对原产于我国的垂丝海棠和引自北美的观赏海棠‘印第安魔力’、‘春雪’花芽分化的形态发育进程进行观察分析。结果表明:垂丝海棠花芽形态分化始于7月中上旬,分化进程可划分为6个阶段:花芽分化前期、花序原基分化期、萼片原基分化期、花瓣原基分化期、雄蕊原基分化期、雌蕊原基分化期,同朵小花各轮原基发育顺序严格,各分化期时间上存在重叠现象。初步判断垂丝海棠营养芽向花芽转变的生理分化期发生在6月上旬至7月中上旬之间,持续时间短于42天。物候观察和切片观察的结果表明垂丝海棠花序类型更偏向于伞形花序而非伞房花序。‘印第安魔力’的花序原基分化期约比‘春雪’晚1个月,这可能是导致‘印第安魔力’的花期相对于‘春雪’较滞后的原因之一。 相似文献
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Differential regulation of two dehydrin genes from peach (Prunus persica) by photoperiod, low temperature and water deficit 总被引：1，自引：0，他引：1
Wisniewski ME Bassett CL Renaut J Farrell R Tworkoski T Artlip TS 《Tree physiology》2006,26(5):575-584
Dehydrins are one of several proteins that have been specifically associated with qualitative and quantitative changes in cold hardiness. Recent evidence indicates that the regulation of dehydrin genes by low nonfreezing temperature (LT) and short photoperiod (SD) can be complex and deserves more detailed analysis to better understand the role of specific dehydrin genes and proteins in the response of woody plants to environmental stress. We have identified a new peach (Prunus persica (L.) Batsch) dehydrin gene (PpDhn2) and examined the responses of this gene and a previously identified dehydrin (PpDhn1) to SD, LT and water deficit. PpDhn2 was strongly induced by water deficit but not by LT or SD. It was also present in the mature embryos of peach. In contrast, PpDhn1 was induced by water deficit and LT but not by SD. We conducted an in silico analysis of the promoters of these genes and found that the promoter region of PpDhn1 contained two dehydration-responsive-elements (DRE)/C-repeats that are responsive to LT and several abscisic acid (ABA)-response elements (ABREs). In contrast, the promoter region of PpDhn2 contained no LT elements but contained several ABREs and an MYCERD1 motif. Both promoter analyses were consistent with the observed expression patterns. The discrepancy between field-collected samples and growth-chamber experiments in the expression of PpDhn1 in response to SD suggests that SD-induced expression of dehydrin genes is complex and may be the result of several interacting factors. 相似文献
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Vegetative buds of peach (Prunus persica L. Batsch.) trees act as strong sinks and their bud break capacity can be profoundly affected by carbohydrate availability during the rest period (November-February). Analysis of xylem sap revealed seasonal changes in concentrations of sorbitol and hexoses (glucose and fructose). Sorbitol concentrations decreased and hexose concentrations increased with increasing bud break capacity. Sucrose concentration in xylem sap increased significantly but remained low. To clarify their respective roles in the early events of bud break, carbohydrate concentrations and uptake rates, and activities of NAD-dependent sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX) and cell wall invertase (CWI) were determined in meristematic tissues, cushion tissues and stem segments. Only CWI activity increased in meristematic tissues shortly before bud break. In buds displaying high bud break capacity (during January and February), concentrations of sorbitol and sucrose in meristematic tissues were almost unchanged, paralleling their low rates of uptake and utilization by meristematic tissues, and indicating that sorbitol and sucrose play a negligible role in the bud break process. Hexose concentrations in meristematic tissues and glucose imported by meristematic tissues correlated positively with bud break capacity, suggesting that hexoses are involved in the early events of bud break. These findings were confirmed by data for buds that were unable to break because they had been collected from trees deprived of cold. We therefore conclude that hexoses are of greater importance than sorbitol or sucrose in the early events of bud break in peach trees. 相似文献
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【目的】明确不同湿度条件下富士系苹果花过冷却点的分布频率,为苹果霜冻监测和预测提供参考。【方法】以中国种植最广泛的富士系苹果为研究对象,使用人工霜冻试验箱控制温湿度,模拟霜冻降温过程,设置高、中、低3个湿度范围,对富士系苹果花蕾和花朵子房过冷却点进行监测,研究环境相对湿度对富士系苹果花器官过冷却点的影响。【结果】富士系苹果花蕾和花朵子房过冷却点在-6.4^-1.9 ℃,50%的过冷却点集中在-4.4^-3.5 ℃,80%的过冷却点集中在-4.4^-2.5 ℃,平均过冷却点为-3.7 ℃。苹果花蕾和花朵子房的累积冻害率达到30%(轻度)的温度为-3.2 ℃,累积冻害率达到50%(中度)的温度为-3.6 ℃,累积冻害率达到80%(重度)的温度为-4.2 ℃。花蕾过冷却点的变异大于花朵子房过冷却点,不同湿度处理下花蕾和花朵子房过冷却点差异显著。中湿(相对湿度50%~70%)条件下,过冷却点最高,抗寒性最差,而低湿(相对湿度50%以下)和高湿(相对湿度大于70%)处理均可降低植株的过冷却点。【结论】-4.4^-2.5 ℃是富士系苹果花组织开始出现损伤的主要温度范围。干燥和高湿的环境均可降低富士系苹果花蕾和花朵的过冷却点,尤其是干燥的环境可降低苹果花蕾的过冷却点0.6 ℃,可降低苹果花朵子房的过冷却点0.4 ℃,提高苹果花蕾及花朵子房抗寒性。 相似文献
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油桐花芽分化期内源激素含量的变化 总被引：3，自引：0，他引：3
为给油桐花芽分化及花期调控的研究提供理论依据.在观察油桐花芽形态分化的显微结构的基础上,测定并分析了该时期油桐叶片中内源激素ZR(玉米索核苷)、IAA(生长素)、GA(赤霉素)、ABA(脱落酸)含量的变化情况.结果表明:当花芽生理分化期,ZR(玉米素核苷)、IAA(生长素)、GA(赤霉素)、ABA(脱落酸)的含量迅速下降,到花芽形态分化开始前降到较低水平;花芽形态分化开始后,ZR(玉米素核苷)、IAA(生长素),GA(赤霉素),ABA(脱落酸)的含量呈现出前期上升、中期波动、末期上升的变化规律;花芽生理分化期,ZR/GA、ZR/IAA、ABA/GA和ABA/IAA之值迅速上升,而当花芽形态分化期,各比值在较高水平上的波动大.后期下降.因此,内源激素间的平衡与综合作用促进了花芽的分化. 相似文献
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为了了解‘辣椒杏’花芽分化时期与分化特点,从而为降低其败育率、丰产栽培及育种提供有效的理论依据,通过外部形态观察及石蜡切片法对‘辣椒杏’等3个杏品种花芽分化进行研究。结果表明:‘辣椒杏’与‘旦杏’花芽分化集中在6月底至8月底,‘库买提’花芽分化集中在6月底至9月初。各品种所经历的分化时期一致,其分化过程分为未分化期、分化初期、萼片分化期、花瓣分化期、雄蕊分化期、雌蕊分化期6个时期。在同一时间可观察到处于不同分化时期的花芽,各时期均有重叠现象,但持续时间不同,‘辣椒杏’与‘旦杏’持续时间较为接近。在6个分化时期中分化初期历时最长,其它时期各品种历时10~30 d不等。‘辣椒杏’与‘旦杏’花芽分化的整体进程比‘库买提’早10 d左右,从花芽开始分化到雌蕊形成,3个品种均历时约90 d。 相似文献
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以杜鹃红山茶为材料,采用石蜡切片法观察花芽分化过程,研究该过程与外部形态的相关性及其代谢产物的变化。结果表明:杜鹃红山茶花芽分化于5—9月间持续不断进行,该时段内能观察到处于不同分化阶段的花芽;其过程可分为生理分化期、花原基分化期、萼片原基分化期、花瓣原基分化期、雄蕊原基分化期、雌蕊原基分化期。杜鹃红山茶花芽分化过程与其外部形态特征之间有着相对稳定的关系,可以通过花芽形态特征来对其进行判别。花芽分化期可溶性蛋白质含量先升高后降低,可溶性糖含量及可溶性糖/可溶性蛋白质先降低后升高;RNA、总核酸含量及RNA/DNA的变化趋势一致,均随花芽分化逐渐升高,在花瓣原基分化期达到最高,雄蕊、雌蕊原基分化期降低,而DNA含量在整个过程中一直处于较低水平且变化平缓。 相似文献
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Bodson M 《Tree physiology》1986,1(1):95-99
Apical buds of evergreen azalea (Rhododendron sp.) were treated with GA(4 + 7) at different stages of development. Treatment of vegetative buds stimulated shoot growth, slightly delayed both flower initiation and development, but increased the number of flower primordia. Treatment at the time of floral transition induced bud abortion at an early stage of the reproductive development. Treatment of inflorescence buds which contained at least one complete flower substituted for chilling in overcoming dormancy and prevented inflorescence bud abortion. 相似文献
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We studied the in vitro responses of cambial tissue and dormant vegetative buds obtained from top and epicormic branches of three mature black locust (Robinia pseudoacacia L.) trees. Cambial tissues isolated from epicormic branches produced more callus than cambial tissues isolated from top branches, whereas in vitro shoot cultures derived from buds excised from top branches grew faster than those derived from buds excised from epicormic branches. There were no significant differences between the two branch sources in in vitro bud break or shoot multiplication from bud explants or cambial-derived callus tissue, respectively. Furthermore, the top branches, generally considered to be the most mature in a tree, were not recalcitrant in terms of morphogenic capacity compared to epicormic branches. 相似文献
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目的]了解和掌握山鸡椒雌花花芽分化的形态特征及碳氮营养规律,为山鸡椒人工栽培及杂交育种提供参考依据。[方法]采用石蜡切片法观察山鸡椒雌花花芽分化的组织解剖结构,采用生理试剂盒-分光光度法测定雌花不同分化时期的可溶性糖、淀粉、可溶性蛋白、碳氮比等碳氮营养指标。[结果]表明:(1)山鸡椒雌花花芽分化经过未分化期—花序原基分化期—苞片原基分化期—花原基分化期—花器官分化期5个时期。(2)叶片可溶性糖含量随着花芽分化的发展呈不断升高的趋势,最高可达65.07 mg·g~(-1)。叶片淀粉含量随着分化时期的推进呈先升后降的趋势,其最高值出现在苞片原基分化期,达到81.30 mg·g~(-1),最低值出现在花器官分化期,为52.19 mg·g~(-1)。(3)叶片可溶性蛋白含量在花芽前3个分化期呈持续下降趋势,从61.32 mg·g~(-1)下降到52.48 mg·g~(-1),之后基本保持稳定。叶片中的碳氮比在花芽前3个分化期呈持续上升趋势,从1.49上升至2.61,之后基本维持在较高水平。[结论]山鸡椒雌花花芽分化的内部形态特征与雄花基本一致,雌花花芽分化分为5个时期。山鸡椒雌花花芽分化过程中,叶片中可溶性糖不断升高,而可溶性蛋白下降明显,碳氮比升高且保持在较高水平。 相似文献
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Bud dormancy of root wrenched and unwrenched slash pine (Pinus elliottii Engelm.) seedlings growing in a forest nursery was measured on five lifting dates. Determination of bud dormancy was based on days to budbreak (DBB) under optimal growing conditions, mitotic activity in the apical meristem, chilling hours accumulated, and bud morphology. Based on DBB, seedlings were most dormant at Lift 2 on November 24 after exposure to 189 hours below 10 degrees C and 93 hours below 6.7 degrees C. Mitotic activity in the apical meristem was at its lowest 23 days later at Lift 3, possibly indicating the period when seedlings are most resistant to transplanting stresses. Multiple wrenching resulted in a slight shift in the dormancy cycle as wrenched seedlings set bud sooner in the nursery and broke bud sooner at the planting site in the spring than control seedlings. This implies that wrenched seedlings can be successfully lifted from the nursery earlier and will initiate spring shoot growth earlier than control seedlings. 相似文献
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DING Xingcui CAI Hanjiang China National Bamboo Research Center Hangzhou P.R.China 《中国林业科技(英文版)》2007,6(2):54-61
By determination of the change of endogenous hormone Zr, iPA, GA3, IAA and ABA during different flower bud differentiation stages of Phyllostachys praecox, which is identified through both field observation and lab analysis, and with the reference to the previous research achievements on bamboo flowering, the flowering mechanism assumption of Phyto-Hormone Regulation and Gene Activation of Ph. praecox is induced in this article： Bamboo flower bud differentiation can be divided into 3 stages, i.e. flower bud induction, flower bud initiation and flower bud development; Bamboo leaves sense and receive flowering signals from environments to change its hormone level, esp. ratios of iPA/ABA and iPA/GA3; Flowering gene is activated once the ratios of iPA/ABA and iPA/GA3 reach a proper threshold, and it produces DNA and RNA carrying flowering code and transports them to top or side buds nearby, and then protein necessary for flower bud differentiation comes out, as a result of which the flower bud induction is trigged and started, followed by flower bud initiation and development. In the induction stage, ratio of C/N is nearly constant, but increases in the initiation stage. Therefore it clarifies that the rising of C/N ratio does not bring about bamboo flowering initially, and it is a follow-up reactions of process initiation of bamboo flowering. It proves that bamboo rhizome is directly involved in the flower bud differentiation. This assumption can well explain mysterious phenomena of bamboo flowering, and by integrating the current several assumptions, answer the difficult and perplexing questions regarding bamboo flowering which have not been answered by the present assumptions. 相似文献