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1.
七叶树繁育系统的研究   总被引:1,自引:0,他引:1  
李莺 《西北植物学报》2012,32(10):1990-1996
对七叶树的开花物候期、花部特征、单花开放动态、花粉活力、柱头可授性、花粉-胚珠比(P/O)和杂交指数(OCI)等有关生殖生物学特性进行了研究。结果表明:(1)在西安地区七叶树4月22日进入初花期,5月5日至13日为盛花期,5月14日进入终花期,整个群花期持续30d左右,单花花期持续5~8d。(2)七叶树的花有雄花和两性花两种形态,其在形态大小和生理上有显著差异,雄花小于两性花,其子房退化,雄花的花粉活力远远大于两性花的花粉活力,雄花开花当天花粉活力最强,达到75.69%,是七叶树授粉的最佳时间;两性花雌雄蕊发育正常,其柱头可授期持续8~9d,开花后3d柱头可授性达到最强。(3)P/O和OCI检测结果均表明,七叶树繁育系统为异交,需要传粉者,属于雄全同株植物。  相似文献   

2.
为揭示特早熟枇杷新品系‘川早枇杷’头花坐果率低的原因,该试验采用田间调查方法观察了‘川早枇杷’头花的开花期,并用联苯胺-过氧化氢法检验了柱头可授性、TTC法测定了花粉活力、苯胺蓝染色法观察了花粉管生长情况。结果显示:(1)‘川早枇杷’头花7月中旬进入初花期,7月下旬至8月上旬为盛花期,8月中旬至下旬为终花期,头花花期的果园气温最高、最低和平均分别为34.9℃、18.9℃和26.03℃。(2)开花当天及花后1~4d柱头具有可授性,且花后1d柱头可授性最强、花粉活力最高,以后花粉活力逐渐迅速降低。(3)自花授粉的花粉管在授粉后48h抵达花柱基部、96h到达胚珠,但数量极少。研究表明,‘川早枇杷’头花具有最佳可授性的时间较短,花粉活力降低迅速,花粉管能够抵达花柱基部和进入胚珠的数量极少,花期高温等诸多因素的综合作用可能是造成其头花坐果不良的重要原因。  相似文献   

3.
滇重楼和毛重楼花粉活力和柱头可授性的研究   总被引:4,自引:0,他引:4  
用TTC法测定了滇重楼和毛重楼花粉的活力,用联苯胺—过氧化氢法测定了其柱头的可授性。结果表明滇重楼的花粉活力在散粉后第1天活力较高以后则逐渐下降,在第2天和第19天花粉活力则急剧下降,但能维持20~23d,在整个花期中基本都具有活力。毛重楼的花粉寿命约为4d,第2天花粉活力达到最大值,第3天后花粉活力急剧下降,总体活力较低。滇重楼和毛重楼的柱头在整个花期中几乎都具可授性,但滇重楼在11~13d时柱头可授性最强,毛重楼在第5天可授性最强。两种重楼植物花粉活力较高的时期与柱头可授性较强的时期不一致,但柱头可授性较强的时间与分泌黏液较多的时间基本一致。  相似文献   

4.
七叶树花粉活力和柱头可授性变化的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
李莺  陈鹏涛  樊静静 《广西植物》2012,32(6):816-821
采用花粉离体萌发法研究不同蔗糖浓度、硼酸浓度和不同温度对七叶树花粉萌发的影响及花粉活力测定,用联苯胺-过氧化氢法测定柱头可授性.结果表明:七叶树花粉萌发的最佳培养基是12%蔗糖+30 mg/L硼酸,花粉萌发的最适温度为25℃.雄花在开花当天花粉活力最高达75.69%,并在开花当天的上午10:00时,花粉活力最强,10:00~16:00花粉活力保持较高活力,是最佳授粉时段.两性花的柱头可授期持续时间较长,为8~9 d,开花3d达到最强,开花1~4 d柱头可授性保持较高水平,为授粉的最佳时间段.因此,从七叶树的花部特征、花粉活力与柱头可授性及花粉萌发的条件看,在长期的自然选择下七叶树在花部结构和开花生理上都是相配合的,以保障生殖成功.  相似文献   

5.
全红型软枣猕猴桃花器结构和开花授粉生物学特性   总被引:2,自引:0,他引:2  
对全红型软枣猕猴桃天源红花器结构、雌花开放动态及寿命、花期温度、柱头可授性、有效授粉期、有效受精期、花粉管行为等进行了系统研究,以探讨影响天源红结实率低下的原因.结果表明:(1)雌花枝可分为以下5种类型:短缩花枝(0~5 cm)、短花枝(5~10 cm)、中花枝(10~30 cm)、长花枝(30~50 cm)和徒长性花枝(>50cm);(2)柱头属于干性柱头,具有一道裂沟,乳突呈长圆柱形;(3)开花过程可分为以下5个阶段:花萼开裂期、花萼大裂期、花瓣变色期、大蕾期和开花期;(4)整个开花过程温度平稳,开花整齐,雌花单花期为1~2 d;(5)柱头可授性在花后1~2 d最强,花开后3~5 d可授性逐渐降低,花后第6天丧失可授性;有效授粉期为开花第1天和第2天;有效受精时期为授粉后5~10 h;(6)授粉后0.5 h花粉就能在柱头乳突细胞表面萌发并进入花柱道生长;授粉后10 h花粉管生长到达花柱底部.初步推断,花期、有效授粉期以及柱头可授性时间短,是天源红坐果率相对较低的主要原因.  相似文献   

6.
芍药花粉活力和柱头可授性的研究   总被引:37,自引:0,他引:37       下载免费PDF全文
红雨  刘强  韩岚 《广西植物》2003,23(1):90-92
用TTC法测定了芍药花粉的活力和寿命,用联苯胺—过氧化氢法测定了其柱头的可授期。结果表明,栽培芍药单瓣花植株的花粉活力和重瓣花植株的花粉活力在开花初期(1~2d)无明显差别,但重瓣花植株的花粉活力比单瓣花植株的花粉活力下降快;通常情况下,花粉寿命约为7d。栽培品种的柱头有个体差异,单瓣花植株有的开花后2h即可分泌粘液,而重瓣花植株的柱头在开花后,有的一直不分泌粘液,有的在开花后两天才分泌粘液;单瓣花植株的柱头可授性比重瓣花植株的强,一般分别在开花后6d和3d之内具可授性。移栽的野生芍药植株的花粉活力比栽培品种下降的慢,其寿命也较长,一般为15d;柱头的可授性和粘液分泌比栽培植株强。  相似文献   

7.
对深山含笑(Michelia maudiae)的花部特征、开花动态、开花物候、花粉活力和柱头可授性进行研究。结果表明:①深山含笑花期为2月下旬至4月中上旬,表现为集中开花模式;②单花开放时间固定,且有二次开合现象,开放过程可分为露白、首次开花期、闭合期和二次展开期共4个时期;③深山含笑在单株水平上为同步集中式开花,单花花期约为7~12 d,单株花期约为20~38 d;④深山含笑柱头在开花前1 d已具有可授性,开放当天可授性最高,随后可授性迅速下降,而雄蕊在开花第2 d开始散粉,花粉活力最高时期为开花第3 d,为(64.6±6.1)%;⑤深山含笑为雌雄异熟且雌蕊先熟,并且雌雄特征有重叠表达阶段,这样不仅可有效减少自交,又可支持自交,足以保证生殖成功。  相似文献   

8.
为探讨枸杞新品系NQ-2纯系种植结实率低的原因,采用TTC法、联苯胺—过氧化氢法、花粉—胚珠比、杂交指数和套袋试验等方法,对NQ-2花粉活力、柱头可授性及繁育系统等进行了研究。结果表明:NQ-2单花花期为3~4 d,花后8 h散粉结束,开花当天花粉活力最高,花粉寿命可持续9 d以上;开花前一天柱头已具可授性,开花第1天柱头可授性最强,开花第3天柱头基本失去可授性;枸杞新品系NQ-2平均花粉-胚珠比8615,OC I=4,结合人工授粉实验结果确定其繁育系统为专性异交。自交不亲和是导致NQ-2纯系种植落花落果结实率低的主要原因。  相似文献   

9.
以南蛇藤花粉和柱头为研究对象,用日立TM-1000扫描电镜(SEM)观察花粉和柱头形态;用TTC(2,3,5-triphenyl tetrazolium chloride)法测定不同贮藏温度对雄花花粉活力的影响;用固体培养基萌发法测定不同温度下雄花花粉的萌发率。结果表明:南蛇藤花粉粒呈长球形,赤道观细长椭圆形,极面观近三裂圆形,具三孔沟,网状雕纹。南蛇藤雌花、两性花的柱头形态及不同发育期的变化规律相似,而雄花柱头形态明显区别于雌花和两性花的。不同的贮藏温度对雄花花粉活力的影响差异明显,贮藏温度越高,花粉失活越快,说明低温利于花粉贮藏。南蛇藤雄花花粉萌发的最适温度约25℃。  相似文献   

10.
野生烟草花粉活力与柱头可授性及繁育特性研究   总被引:3,自引:0,他引:3  
采用TTC法测定2个野生烟草材料(花烟草、哥西氏烟草)和1个栽培品种(K326)的花粉活力及其日变化情况,通过联苯胺-过氧化氢法测定3个烟草材料的柱头可授性、利用直接授粉法测定不同开花天数柱头可授性变化,并通过估算花粉胚珠比(P/O)、杂交指数(OCI)及授粉试验分析3个烟草材料的繁育特性。结果表明:(1)哥西氏烟草的花粉活性(74.9%)显著高于K326(52.2%)和花烟草(45.3%),且K326与花烟草间差异不显著;3个烟草材料花粉活力日变化均呈双峰曲线,峰值分别在13:00与15:00左右,且3个烟草材料的花粉活力日最低值与气温日最高值同时出现在14:00。(2)K326柱头可授性显著高于花烟草和哥西氏烟草,且2个野生烟草间可授性无显著差异;不同烟草的最佳授粉时期不同,哥西氏烟草自开花前1d至花后4d,一直保持较高的柱头可授性;花烟草的最佳授粉时期为花后2~3d;K326的柱头在开花前1d至开花后1d授粉最佳。(3)K326以自交为主,存在异交现象;哥西氏烟草繁育类型为兼性异交,自交亲和;花烟草繁育以异交为主,自交亲和性差。研究认为,野生烟草柱头可授性显著低于栽培品种从而影响其结实性,花烟草结实率低主要是由自交不亲和性造成的,而缺乏有效的传粉机制是造成哥西氏烟草结实性差的主要原因。  相似文献   

11.
A systematic electronic PubMed, Medline and Web of Science database search was conducted regarding the prevalence, correlates, and effects of personal stigma (i.e., perceived and experienced stigmatization and self‐stigma) in patients with schizophrenia spectrum disorders. Of 54 studies (n=5,871), published from 1994 to 2011, 23 (42.6%) reported on prevalence rates, and 44 (81.5%) reported on correlates and/or consequences of perceived or experienced stigmatization or self‐stigma. Only two specific personal stigma intervention studies were found. On average, 64.5% (range: 45.0–80.0%) of patients perceived stigma, 55.9% (range: 22.5–96.0%) actually experienced stigma, and 49.2% (range: 27.9–77.0%) reported alienation (shame) as the most common aspect of self‐stigma. While socio‐demographic variables were only marginally associated with stigma, psychosocial variables, especially lower quality of life, showed overall significant correlations, and illness‐related factors showed heterogeneous associations, except for social anxiety that was unequivocally associated with personal stigma. The prevalence and impact of personal stigma on individual outcomes among schizophrenia spectrum disorder patients are well characterized, yet measures and methods differ significantly. By contrast, research regarding the evolution of personal stigma through the illness course and, particularly, specific intervention studies, which should be conducted utilizing standardized methods and outcomes, are sorely lacking.  相似文献   

12.
Stigmas in 24 species of 11 genera, classified in three groups, Caesalpinia, Peltophorum and Dimorphandra, of the tribe Caesalpinieae have been examined by light and scanning electron microscopy. All are of the WN (wet, non-papillate) form. The receptive stigmatic surface comprises a crater, generally at the apex of the style, which in fresh flowers is full of clear fluid. The crater rim may be fringed with non-receptive hairs, and its shape and depth are variable between species. Extreme forms are found in Caesalpinia sappan where crater hairs are short and the crater funnel-shaped and very deep, and C. vesicaria and Delonix regia where crater hairs are long and the crater appears very shallow.  相似文献   

13.
烟台甜樱桃柱头的可授性、形态特征与坐果率   总被引:2,自引:0,他引:2  
采用数码照相、电镜扫描、联苯胺-过氧化氢测试及去雄套袋等技术手段, 对烟台甜樱桃(Cerasus avium)花期不同发育阶段柱头的可授性、形态特征和坐果状况进行了观察。结果表明, 烟台甜樱桃在套袋状态下, 柱头可授期从开花前1天开始可持续5–7天。从杯状花期到花瓣平展期, 柱头逐渐有乳突细胞破裂并呈现分泌液, 出现渐强的可授性; 从花瓣平展期到花瓣脱落期, 柱头由暗黄渐变至暗黑, 逐渐萎缩并丧失可授性。去雄套袋及人工授粉实验结果显示, 在大蕾期、杯状花期、花瓣展放期、花瓣平展期和花瓣脱落期进行人工授粉, 烟台甜樱桃的坐果率分别为60.50%、58.33%、62.08%、57.14%和39.13%。在自然条件下烟台甜樱桃的坐果率一般为30%–42%, 传粉成功的最佳期主要发生在杯状花期至花瓣平展期。  相似文献   

14.
美国凌霄柱头行为——一种促进传粉的机制(英文)   总被引:4,自引:0,他引:4  
引起美国凌霄(campsis radicans(L.)Seem.ex Bureau.)柱头开合行为的原因迄今未知。在本研究中,机械刺激、自花授粉、异花授粉以及不同授粉数量的授粉分别给予美国凌霄的柱头,以期找到影响其柱头行为的原因。研究结果表明,单纯的机械刺激可以使柱头闭合,但不能使之永久闭合;只有柱头表面落置了足够量的花粉(>350)时柱头才会最终闭合。美国凌霄的柱头行为对自花或者异花花粉没有差异,两种花粉授于柱头后花粉管都能成功地萌发并生长。研究结果说明:美国凌霄的柱头行为不是一种异交机制,而是一种促进传粉进而增强繁殖成功的机制。  相似文献   

15.
美国凌霄柱头行为--一种促进传粉的机制   总被引:2,自引:0,他引:2  
引起美国(Campsis radicans(L.)Seem.ex Bureau.)柱头开合行为的原因迄今未知.在本研究中,机械刺激、自花授粉、异花授粉以及不同授粉数量分别给予美国凌霄的柱头,以期找到影响其柱头行为的原因.研究结果表明,单纯的机械剌激可以使柱头闭合,但不能使之水永久闭合;只有柱头表明落置了足够量的花粉(>350)时柱头才会最终闭合.美国凌霄的柱头对换自花或者花粉没有差异,两种花粉授于柱头后花粉管都能成功萌发并生长.研究结果表明:美国凌霄的柱头行为不是一种异交机制,而是一种促进传粉进而增强繁殖成功的机制.  相似文献   

16.
采用数码照相、电镜扫描、联苯胺-过氧化氢测试及去雄套袋等技术手段,对烟台甜樱桃(Cerasus avium)花期不同发育阶段柱头的可授性、形态特征和坐果状况进行了观察。结果表明,烟台甜樱桃在套袋状态下,柱头可授期从开花前1天开始可持续5–7天。从杯状花期到花瓣平展期,柱头逐渐有乳突细胞破裂并呈现分泌液,出现渐强的可授性;从花瓣平展期到花瓣脱落期,柱头由暗黄渐变至暗黑,逐渐萎缩并丧失可授性。去雄套袋及人工授粉实验结果显示,在大蕾期、杯状花期、花瓣展放期、花瓣平展期和花瓣脱落期进行人工授粉,烟台甜樱桃的坐果率分别为60.50%、58.33%、62.08%、57.14%和39.13%。在自然条件下烟台甜樱桃的坐果率一般为30%–42%,传粉成功的最佳期主要发生在杯状花期至花瓣平展期。  相似文献   

17.
People who live with mental illnesses are among the most stigmatized groups in society. In 1996, in recognition of the particularly harsh burden caused by the stigma associated with schizophrenia, the WPA initiated a global anti-stigma program, Open-the-Doors. In 2005, a WPA Section on Stigma and Mental Health was created, with a broader mandate to reduce stigma and discrimination caused by mental disabilities in general. In light of these impor-tant developments, and the growing public health interest in stigma reduction, this paper reflects on the past perspectives that have led us to our current position, reviews present activities and accomplishments, and identifies challenges that the Section members will face in their future efforts to reduce the stigma caused by mental disorders.  相似文献   

18.
Objectives: The purpose of this research was to examine the social, educational, and psychological correlates of weight status in an adolescent population. It was hypothesized that obese adolescents would differ on psychological, social, and educational variables compared with their non‐overweight peers. Research Methods and Procedures: In this cross‐sectional study, a population‐based sample of 4742 male and 5201 female public school students in the 7th, 9th, and 11th grades responded anonymously to a classroom administered questionnaire. Body mass index was calculated from self‐reported height and weight and categorized into four classes of weight status: underweight (<15th percentile), average weight (15th to 85th percentile), overweight (>85th to 95th percentile), and obese (>95th percentile). The questionnaire also included questions about social experiences, psychological well‐being, educational experiences, and future goals. Associations of weight status with social, psychological, and educational variables and future goals were explored. Results: After adjustment for grade level, race, and parental socioeconomic status, obese girls, when compared with their average weight counterparts, were 1.63 (95% confidence interval [CI]: 1.16, 2.30) times less likely to hang out with friends in the last week, 1.49 (95% CI: 1.12, 1.98) times more likely to report serious emotional problems in the last year, 1.79 (95% CI: 1.20, 2.65) times more likely to report hopelessness, and 1.73 (95% CI: 1.21, 1.98) times more likely to report a suicide attempt in the last year. Obese girls were also 1.51 (95% CI: 1.09, 2.10) times more likely to report being held back a grade and 2.09 (95% CI: 1.35, 3.24) times more likely to consider themselves poor students compared with average weight girls. Compared with their average weight counterparts, obese boys were 1.91 (95% CI: 1.43, 2.54) times less likely to hang out with friends in the last week, 1.34 (95% CI: 1.06, 1.70) times more likely to feel that their friends do not care about them, 1.38 (95% CI: 1.08, 1.76) times more likely to report having serious problems in the last year, 1.46 (95% CI: 1.05, 0.03) times more likely to consider themselves poor students, and 2.18 (95% CI: 1.45, 3.30) times more likely to expect to quit school. Compared with average weight boys, underweight boys were 1.67 (95% CI: 1.30, 2.13) times more likely to report hanging out with friends in the last week, 1.22 (95% CI: 1.01, 1.49) times more likely to report disliking school, and 1.40 (95% CI: 1.06, 1.86) times more likely to consider themselves poor students. Discussion: Associations of weight status with social relationships, school experiences, psychological well‐being, and some future aspirations were observed. Among girls, the pattern of observations indicates that obese girls reported more adverse social, educational, and psychological correlates. Obese as well as underweight boys also reported some adverse social and educational correlates. These findings contribute to an understanding of how adolescent experiences vary by weight status and suggest social and psychological risks associated with not meeting weight and body shape ideals embedded in the larger culture.  相似文献   

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