温度对植物成花的影响

温度对于植物成花的影响是多方面的,本文主要从低温、高温和昼夜温差三方面综述了温度影响成花之生理学方面的研究结果。认为温度处理的效果发生于成花启动之前和/或成花启动进程中的较早步骤,其作用可能是间接的。     

光温外界信号、植株状态与成花决定

植物由营养生长状态转向生殖生长状态(成花转变)是发育过程中的重要一步。经过一段时期营养生长的植株,便自动进入成花感受态,在这种状态下植株才能够对外界信号产生应答反应而启动成花过程。本文主要讨论光周期和温度对成花的作用。     

光温外界信号、植株状态与成花决定

植物由营养生长状态转向生殖生长状态（成花转变）是发育过程中的重要一步。经过一段时期营养生长的植株,便自动进入成花感受态,在这种状态下植株才能够对外界信号产生应答反应而启动成花过程。本文主要讨论光周期和温度对成花的作用     

环境因子在植物成花诱导中的作用及其机理

高等植物的碾化规律决定于其遗传性,但是成花的基因表达还受到多和中环境因子没程度的影响。光和温度是成花诱导中最有影响的环境因子。对于光和温度等成花诱导中的作用机理,人们先后提出很多学说。     

光周期和外源糖对新铁炮百合生长和内源糖含量的影响

糖类和光周期是植物成花启动中的重要因素,二者相互作用,共同调节植物成花。新铁炮百合(Lilium×formolongi)具有短生育期的特性,在适宜条件下,一年内可实现从播种到开花。为此,对新铁炮百合品种‘雷山三号’实生苗进行不同光周期和外施蔗糖的处理,探究其对内源糖、海藻糖-6-磷酸含量及对成花诱导的影响。结果表明:在长日照条件下外施蔗糖可以提高抽葶率,并缩短抽葶时间和可见花蕾出现的时间;同时提高植株体内蔗糖和海藻糖-6-磷酸的含量。植株体内葡萄糖含量受光周期影响较大呈现不同变化趋势,而果糖含量在四种不同处理中未表现出明显变化趋势,并且植株体内海藻糖-6-磷酸和蔗糖含量呈现显著正相关。综合而言,光周期是新铁炮百合成花启动的主要影响因素,外施蔗糖在长日照下对成花的促进作用更为明显。     

高等植物春化作用研究进展

环境因子(低温诱导或称春化作用)在高等植物的生长发育调控中起着重要作用。本文就近年来春化作用诱导的开花启动研究领域中的进展从春化过程中的多步骤性、成花决定过程控制的多途径性、接受春化刺激的位置与分化启动的关系、以及春化作用的分子机理等几个方面进行了简要综述。并对春化相关基因克隆方面的进展进行了分析和综述。     

高等植物春化作用研究进展

环境因子（ 低温诱导或称春化作用） 在高等植物的生长发育调控中起着重要作用。本文就近年来春化作用诱导的开花启动研究领域中的进展从春化过程中的多步骤性、成花决定过程控制的多途径性、接受春化刺激的位置与分化启动的关系、以及春化作用的分子机理等几个方面进行了简要综述。并对春化相关基因克隆方面的进展进行了分析和综述     

环切对苹果缺枝顶芽内源多胺水平的影响及其与成花的关系

研究了环切对６年生富士、金冠苹果缺枝内源多胺,包括腐胺、亚精胺和精胺的含量及其与成花的关系,发现内源多胺含量与成花作用显著相关。在花诱导阶段,Ｐｕｔ和Ｓｐｄ的含量呈下降趋势,主枝环切处理在促进成花的同时减缓了多胺下降的速率,Ｓｐｍ的含量呈下降趋势。表明Ｐｕｔ有助于分生组织的活化,而ＳｐｄＴ和Ｓｐｍ与花诱导的启动及促进有关。     

龙眼的成花逆转与“冲梢”调控

龙眼的成花逆转以部分开花和／或花序逆转两种类型出现,其逆转是以“冲梢”形成而发生的,“冲梢”导致龙眼“大小年”结果。文章就60年代以来龙其是近10来年龙眼花芽分化和成花逆转,与成花逆转有关的因素,以及成花转调控等方面的研究进展作介绍。     

环切对苹果短枝顶芽内源多胺水平的影响及其与成花的关系

研究了环切对6年生富士、金冠苹果短枝内源多胶,包括腐胶、亚精胺和精胺的含量及其与成花的关系,发现内源多胺含量与成花作用显著相关。在花诱导阶段,Put和Spd的含量呈下降趋势,主枝环切处理在促进成花的同时减缓了多胺下降的速度,Spm的含量出现峰值;在形态分化阶段初期,Put和Spd的含量继续下降,至形态分化末期,含量迅速上升。而Spm含量呈下降趋势。表明Put有助于分生组织的活化,而Spd和Spm与花诱导的启动及促进有关。     

Two reproductive traits show contrasting genetic architectures in Plantago lanceolata

In many species, temperature‐sensitive phenotypic plasticity (i.e., an individual's phenotypic response to temperature) displays a positive correlation with latitude, a pattern presumed to reflect local adaptation. This geographical pattern raises two general questions: (a) Do a few large‐effect genes contribute to latitudinal variation in a trait? (b) Is the thermal plasticity of different traits regulated pleiotropically? To address the questions, we crossed individuals of Plantago lanceolata derived from northern and southern European populations. Individuals naturally exhibited high and low thermal plasticity in floral reflectance and flowering time. We grew parents and offspring in controlled cool‐ and warm‐temperature environments, mimicking what plants would encounter in nature. We obtained genetic markers via genotype‐by‐sequencing, produced the first recombination map for this ecologically important nonmodel species, and performed quantitative trait locus (QTL) mapping of thermal plasticity and single‐environment values for both traits. We identified a large‐effect QTL that largely explained the reflectance plasticity differences between northern and southern populations. We identified multiple smaller‐effect QTLs affecting aspects of flowering time, one of which affected flowering time plasticity. The results indicate that the genetic architecture of thermal plasticity in flowering is more complex than for reflectance. One flowering time QTL showed strong cytonuclear interactions under cool temperatures. Reflectance and flowering plasticity QTLs did not colocalize, suggesting little pleiotropic genetic control and freedom for independent trait evolution. Such genetic information about the architecture of plasticity is environmentally important because it informs us about the potential for plasticity to offset negative effects of climate change.     

大豆开花后光周期反应的研究

利用中国大豆主要生态区的生育期不同的代表品种研究了大豆（Ｇｌｙｃｉｎｅ ｍ ａｘ （Ｌ．）Ｍｅｒｒ．）开花后对光照长度的反应． 结果表明,不同成熟期的大豆品种开花后普遍存在着对光照长度的反应．这种反应属于典型的光周期现象,而不是由温度的替代作用、光合时间的改变或前期短日后效应引起的．开花后光周期反应不仅存在于大豆的花荚期,而且存在于鼓粒期．研究认为∶大豆开花结实对光周期的需求是一个连续过程;光周期对大豆生育期的调控作用存在于出苗至成熟的全过程;光周期诱导开花和促进成熟的作用有一定的共同性;光周期诱导效果具有持效性和可逆性     

Increased variance in temperature and lag effects alter phenological responses to rapid warming in a subarctic plant community

Summer temperature on the Cape Churchill Peninsula (Manitoba, Canada) has increased rapidly over the past 75 years, and flowering phenology of the plant community is advanced in years with warmer temperatures (higher cumulative growing degree days). Despite this, there has been no overall shift in flowering phenology over this period. However, climate change has also resulted in increased interannual variation in temperature; if relationships between phenology and temperature are not linear, an increase in temperature variance may interact with an increase in the mean to alter how community phenology changes over time. In our system, the relationship between phenology and temperature was log‐linear, resulting in a steeper slope at the cold end of the temperature spectrum than at the warm end. Because below‐average temperatures had a greater impact on phenology than above‐average temperatures, the long‐term advance in phenology was reduced. In addition, flowering phenology in a given year was delayed if summer temperatures were high the previous year or 2 years earlier (lag effects), further reducing the expected advance over time. Phenology of early‐flowering plants was negatively affected only by temperatures in the previous year, and that of late‐flowering plants primarily by temperatures 2 years earlier. Subarctic plants develop leaf primordia one or more years prior to flowering (preformation); these results suggest that temperature affects the development of flower primordia during this preformation period. Together, increased variance in temperature and lag effects interacted with a changing mean to reduce the expected phenological advance by 94%, a magnitude large enough to account for our inability to detect a significant advance over time. We conclude that changes in temperature variability and lag effects can alter trends in plant responses to a warming climate and that predictions for changes in plant phenology under future warming scenarios should incorporate such effects.     

中国北方主产地苹果冷热积累变化及其对始花期的影响

开展气候变化背景下苹果冷热积累变化及其对始花期的影响研究,对指导苹果种植及生产具有重要意义。本研究选取山东福山、山西万荣、甘肃西峰和新疆阿克苏代表中国北方苹果主产地,利用1996—2018年红富士苹果的始花期观测资料和逐时气温数据,采用动态模型、生长度小时模型分别计算逐日冷积累量(CP)和热积累量(GDH),并利用偏最小二乘回归法,对逐日冷、热积累量和各地苹果始花期进行相关分析,以明确各地苹果冷、热积累起止日期和积累量,以及冷、热积累期内温度变化对始花期的影响规律。结果表明: 我国北方主产地苹果冷积累时段集中于10月1日前后至2月中下旬或3月中旬,积累量为74.1～89.3 CP;热积累时段集中于1月下旬前后至始花期,积累量为4010～5770 GDH。西峰和阿克苏冷积累期内平均气温每升高1 ℃,冷积累量将分别增加3.8和5.0 CP;各地热积累期内平均气温每升高1 ℃,热积累量将增加725～967 GDH。与冷积累期内温度变化的影响效应相比,热积累期内温度变化主控我国北方主产地苹果始花期,且气候变暖总体有利于冷积累期内平均气温较低地区的苹果开花和生产。     

近五十年北京板栗始花物候对光合有效辐射变化的响应

与全球范围内气候变暖对植物物候影响研究相比,其他气候因素（如光合有效辐射PAR等）对物候影响报道较少,果树花期物候对光合有效辐射变化响应的研究更是未见报道。本研究以1963—2008年间北京板栗始花物候资料及相应的日光合有效辐射数据为基础,利用偏最小二乘回归法确定了PAR影响板栗始花物候的两个关键阶段,进而分析了两阶段内PAR、温度及相对湿度变化对板栗花期的具体影响。结果表明,北京过去50年两相关阶段内PAR呈显著下降趋势,其中9月24日至次年2月5日问PAR下降对板栗花期提前具有促进作用,可解释12％的花期提前趋势;2月6日至次年5月31日间PAR下降促使花期延迟,但未达显著水平（P〉0．1）。板栗花期提前主要与2月6日至次年5月31日间温度升高有关,其间温度变化可解释41％的花期提前趋势;其次是相对湿度,PAR变化对花期影响较小。鉴于PAR、温度及相对湿度间的互作效应,PAR和相对湿度对花期物候的影响可由温度效应加以解释。     

Response of Chestnut Flowering in Beijing to Photosynthetically Active Radiation Variation and Change in Recent Fifty Years

Climate warming has affected plant phenology throughout the world, but few studies have evaluated plant phenology response to other climate factors (eg. photosynthetically active radiation PAR). In particular, the response of fruit flowering to PAR variation has not been explored yet. Long term (1963-2008) of chestnut (Castanea mollissima Blume) first flowering dates from Beijing, China were related with daily PAR for the 12 months, using Partial Least Squares (PLS) regression analysis. Two relevant phases were identified, during which mean PAR, temperature, and relative humidity (RH) were correlated with flowering dates, respectively. PAR during the both relevant periods decreased significantly in Beijing over the past 50 years. Reduced PAR during 24 September 5 February showed an advance impact on chestnut flowering, and could explain 12% of advance trend in flowering timing. Deceased PAR during 6 February 31 May had a delayed effect on tree flowering, but it was not significant enough to reject the null hypothesis of no impact over time. Advanced flowering of chestnut was mainly determined by increasing temperature between 6 February and 31 May which could explain 41% of flowering trend. Relative humidity variation during this period played secondly important role on tree flowering. Considering the interaction among these three climate factors, the impacts of PAR and RH on flowering timing could partially be attributed to the effects of temperature variation.     

Phytochrome control of flowering is temperature sensitive and correlates with expression of the floral integrator FT

In Arabidopsis flowering is accelerated by reduced red:far-red (R:FR) ratio which signals the presence of neighbouring vegetation. Hastened flowering is one component of the shade-avoidance syndrome of responses, which alter many aspects of development in response to the threat of potential competition. Of the red/far-red-absorbing photoreceptors it is phyB that plays the most prominent role in shade-avoidance, although other related phytochromes act redundantly with phyB. It is well established that the phyB mutant has a constitutively early flowering phenotype. However, we have shown that the early flowering phenotype of phyB is temperature-dependent. We have established that this temperature-sensitive flowering response defines a pathway that appears to be independent of the autonomous-FLC pathway. Furthermore, we have demonstrated that the phytochromes control the expression of the floral promoter FT. We have also shown that other phyB-controlled responses, including petiole elongation, are not sensitive to the same temperature change. This suggests that discrete pathways control flowering and petiole elongation, components of the shade-avoidance response. This work provides an insight into the phytochrome and temperature interactions that maintain flowering control.     

Flowering timing prediction in Australian native understorey species (Acrotriche R.Br Ericaceae) using meteorological data

The aim of this study was to determine the climatic influences on floral development for five members of the Australian native plant genus Acrotriche R. Br (Ericaceae). An observed period of summer floral dormancy suggests temperature is involved in flowering regulation in these species. Models were developed to determine temperature requirements associated with the likelihood of flowering occurring on any one day. To this end, the timing of flowering and meteorological data were collated for several sites, and multivariate logistic regressions performed to identify variables with a significant influence on flowering timing. The resultant models described a large amount of variation in flowering presence/absence, with r ² values ranging from 0.72 to 0.79. Temperature was identified as influential on both floral development and flowering timing in each of the study species. The positive influence of short photoperiods on flowering in three of the winter flowering species was not surprising. However, the reporting here of a significant association between interdiurnal temperature and flowering in one species is novel. The predictive power of the models was validated through a jackknife sequential recalculation approach, revealing strong positive and negative predictive ability for flowering for four of the five species. Applications of the models include assisting in determination of the suitability of areas for vegetation restoration and identifying the possible effects of climate change on flowering in the study species.     

Regulation of flowering time using temperature,photoperiod and spermidine treatments in Anoectochilus roxburghii

This study investigated the effects of different temperatures, photoperiods and spermidine concentrations on the flowering time regulation of Anoectochilus roxburghii by measuring changes in the soluble sugar, soluble protein, malondialdehyde and proline contents, and the peroxidase, superoxide dismutase and catalase activities in A. roxburghii flower buds. The flowering time could be advanced under 25/20 °C (day/night), 16/8-h (day/night) long day conditions or low spermidine concentrations. The plants grew more rapidly and flowering rates were greater. The flowering time could be delayed under a low temperature of 20/15 °C or 8/16-h short day conditions, resulting in a low flowering rate. Under a high temperature of 30/25 °C or high spermidine concentrations, the plants could not flower normally and even died. There were significant differences in the seven measured indices among the various treatments. Thus, different treatments had significant effects on the flowering time regulation and flowering quality of A. roxburghii, providing a reliable theoretical basis for further studies on the flowering-related regulatory mechanisms of A. roxburghii.