Incompatibility Between the Dimorphic Flowers of Collomia grandiflora, a Cleistogamous Species

The cleistogamous species Collomia grandiflora produces dimorphic cross-incompatible flowers on a single plant. The open or chasmogamous flower has smaller, flask-shaped stigmatic papillae, larger pollen grains, longer styles, and faster pollen tube growth rates down the style than the closed or cleistogamous flower. In intermorph crosses, pollen tube growth rates are greatly decreased and fertilization does not occur.     

台农1号芒果一次花和二次花的特性研究

为了探讨比较台农1号芒果“一年两熟”栽培过程中一次花和二次花的形态特性,对其一次花和二次花的花序长度、花朵直径、两性花比率、花粉活性、花粉量及花粉形态、大小进行了试验研究。结果表明：一次花和二次花的花序平均长度分别为30.74cm和20.67cm;一次花和二次花的直径平均长度分别为7.30mm和6.55mm;一次花和二次花的两性花比率较低,一次花的两性花比率为20.06%,二花的两性花比率为28.79%;一次花的花粉活性比二次花的花粉活性高,一次花的花粉活性为12.90%,二次花的花粉活性为7.63%;一次花的每花花药含花粉量为500个,二次花的每花花药含花粉量为333个;台农1号一次花和二次花的花粉形态可分为长椭圆形花粉、椭圆形花粉、近圆形花粉和不规则形花粉4个类型。     

中华猕猴桃（Actinidia Chinensis）雌雄异株性状变异的研究

通过２ａ调查，发现了介于中华猕猴桃雌株与雄株之间的中间类型，但该类型数量稀少，在野生群体中只占０．５％左右。雌雄异株性状的变异可以从雌株、雄株以及中间类型的花器发育水平上体现。雌花的雌蕊可育，但花粉没有生活力；雄花雌蕊败育，但花粉正常；而中间类型花朵的雌蕊部分发育，而且花粉也有生活力。仅在雌株与中间类型上可以见到明显的“柱头一花柱”结构，但二者在柱头表面乳突的密度与发育水平上显著不同。中间类型花朵的柱头上乳突稀少，而且部分萎陷；花粉粒能在其柱头上发芽，但大多数花粉管不能伸入柱头组织。中间类型的发现不仅对研究雌雄异株性状的演化有一定意义，而且也为培育中华猕猴桃雌雄同株新品种奠定了基础。     

虫媒花与风媒花花粉形态的比较

为了比较虫媒花与风媒花花粉形态上的差异,利用扫描电镜（SEM）对多种虫媒花与风媒花植物的花粉进行了观察。结果表明,虫媒花的花粉形状倾向于长球形,个体普遍比风媒花大;其外壁较粗糙,一级雕纹深刻,大多具次级雕纹。有些虫媒花的花粉具有刺状或疣状突起,有的植物（杜鹃）花粉的外壁具有粘丝。而风媒花中除了具气囊的松型花粉较大外,花粉个体普遍比较小,形状倾向于球形;其外壁比较光滑,一级雕纹大多较浅,为微弱或模糊的细网状或细颗粒状雕纹,基本上无明显的次级雕纹。因此．花粉形态的特征使虫媒花花粉有利于粘附在昆虫身体上传播。而使风媒花的花粉有利于逸散到空气中传播。     

泰国金白花芒花器官及花粉生物学特性研究

为更好地了解泰国金白花芒花器官及花粉生物学特性,对其花的生物学特性、两性花比率及花粉形态进行了观察,并对花粉育性进行了检测.结果表明,花的类型主要为雄花和两性花,花小但量多;两性花比例较低,仅为17.99%,但南面花序初花期两性花比例达到47.83%;其花药饱满,每枚花药含花粉粒408个;其花粉染色活力较低,为14.0...     

Strange floral attractors: pollinator attraction and the evolution of plant sexual systems

Individual plants of hummingbird-pollinated Besleria triflora display two flower morphs: staminate flowers, which have shortened styles and do not produce fruit, and hermaphrodite flowers. Experiments with B. triflora indicate that pollinator attraction can drive the evolution of a dimorphic plant sexual system. In field-manipulated plants, visitation increased at large floral displays; however, pollen receipt increased only when staminate flowers were used to enlarge the display. Laboratory experiments showed that staminate flowers do not remove pollen from visiting pollinators, effectively concentrating outcross pollen onto stigmas of fertile flowers. A dimorphic sexual system is favored because the morphology of staminate flowers enhances their role in pollinator attraction.     

文冠果两性花花粉败育原因的进一步研究

本文利用光镜、透射电镜及电泳和薄板薄膜层析技术对文冠果两性花和单性花(雄花)花药的绒毡层和花粉壁的发育及其营养成分进行了分析比较.结果表明,两种不同类型的花粉在绒毡层和细胞壁的发育方面没有明显差别,但两性花的花粉内壁较厚,细胞器和淀粉的贮存明显不足,且缺乏蔗糖等化合物,氨基酸的种类也较可育花粉少.两类花粉中蛋白质多肽的组成及过氧化物酶和酯酶同工酶的谱带也有明显的差异.因此,文冠果两性花花粉败育的原因可能与花粉中某些细胞器的减少,及生理生化代谢上的障碍造成花粉缺乏足够的营养物质等因素有关.     

不同糖源在球根花卉花粉萌发过程中的作用

以百合、唐菖蒲、郁金香和风信子等4种球根花卉花粉作为试材,研究了淀粉、果糖、麦芽糖、葡萄糖、乳糖和蔗糖等6种不同糖源的培养基对不同球根花卉花粉萌发率和花粉管生长状况的影响。结果表明,不同球根花卉花粉萌发对外源糖的利用存在选择性,对于不同植物种类,各糖源适宜的处理浓度也有所不同。唐菖蒲、郁金香和风信子对外源糖具有依赖性,而百合花粉在蒸馏水培养基中也能萌发。乳糖在各类球根花卉花粉萌发中的促萌效果最为显著,而其他糖源在球根花卉花粉萌发过程中的作用则稍有差异,对唐菖蒲、郁金香与风信子花粉,仅次于乳糖的糖源是葡萄糖,对于索邦百合花粉和兰州百合花粉较次的糖源分别为麦芽糖和蔗糖,淀粉的效果最差。     

熊蜂携粉足结构观察与访花类型研究

通过对长白山常见熊蜂类群及其访花类型进行调查,分析花粉的结构特征及熊蜂携粉足的结构特点,总结出熊蜂偏爱访问植物花粉特征与熊蜂携粉足形态特征之间的关系。结果表明:熊蜂访花类型是由花粉及携粉足特征、环境等因素共同决定。     

文冠果同源异型变异株的发现

该文对北京林业大学苗圃内发现的一文冠果的同源异型自然变异株进行了形态及解剖学观察．结果发现：这一花器官变异植株的花明显小于正常株的花,且不能完全开放,始终呈半开状．花重瓣多轮,仅具花萼和花瓣,不具雄蕊和雌蕊．因为雄蕊和雌蕊全部特化为花瓣状,部分特化的内轮花瓣上留有花药的残迹,花药内的花粉发育是不正常的．与此相关的营养体特征是变异株的叶片大,厚且颜色呈深黑绿色．     

单瓣与重瓣樱花雌雄蕊发育的比较研究

对单瓣和重瓣樱花雌雄蕊的发育进行了系统观察。结果表明:单瓣樱花‘大岛樱’雌蕊1心皮1室,胚珠发育后心皮开始愈合,2倒生胚珠,通常仅有1个能发育为成熟胚囊,双珠被,厚珠心,大孢子四分体线型排列,胚囊发育方式属蓼型;雄蕊小孢子四分体为四面体型,成熟花粉为二细胞型。重瓣樱花‘普贤像’和‘一叶’雄蕊数量显著少于‘大岛樱’,花药瓣化,花粉败育,雌蕊叶化。‘普贤象’少数花萼筒上着生异位子房和败育胚珠,‘一叶’少数花未完全叶化的子房内壁着生败育胚珠;‘普贤象’和‘一叶’均存在同株花异型现象。并对樱花重瓣花形态建成的分子机制展开了探讨。     

Ancient bisexual flowers

Fossil flowers discovered in 94-million-year-old clays of the Dakota Formation in Nebraska are among the earliest known demonstrably bisexual flowers. The flowers are of medium size and have pentamerous whorls of clearly differentiated floral parts, petals alternate with the sepals, short stamens are borne opposite the petals, the carpels are fused, and a receptacular disk is present. The pollen is small and tricolporate. These flowers appear to be well adapted to insect pollination. The numerous floral features and pollen characters provide sufficient diagnostic data to assess its systematic position. No extant order accommodates the features of this flower and it shares some features of various extant orders. The classification of flowering plants and our understanding of their evolution must be influenced by the fossilized remains of ancient flowers.     

Lower cretaceous angiosperm flowers: fossil evidence on early radiation of dicotyledons

Three-dimensionally preserved unisexual angiosperm flowers and inflorescences have been recovered from the Lower Cretaceous Patapsco Formation (Potomac Group) of eastern North America, in sediments palynologically dated as late Albian, approximately 100 million years old. In situ tricolpate pollen shows that the flowers were produced by some of the earliest higher (nonmagnoliid) dicotyledons, and the morphology of pollen, flowers, and inflorescences indicates a close relation to extant Platanaceae. Combined with architectural and cuticular features of associated leaves these floral remains suggest that Platanus-like plants with unisexual, probably insect-pollinated flowers were an important element in the mid-Cretaceous diversification of dicotyledonous flowering plants.     

Lower eocene and paleocene gentianaceae: floral and palynological evidence

Lower Eocene flowers with Pistillipollenites macgregorii pollen represent the earliest megafossil evidence of the Gentianaceae. The Paleocene occurrence of P. macgregorii, the fossil's modern floral structure, and suggested trends in the evolution of pollen in the Gentianaceae indicate a considerably earlier origin for the family. Floral morphology typical of bee-pollinated flowers provides the earliest, albeit indirect, fossil evidence of bees.     

6个非洲菊品种的花粉特性及其离体萌发

为研究不同条件下的花粉特性及其离体萌发,笔者通过测定6个非洲菊(Gerbera jamesonii Bolus)品种的花粉形态、花粉数量和花粉活力,明确花粉特性和不同条件下的花粉活力;利用spss 23.0软件进行花粉大小、形态指数和花粉数量的系统聚类分析。结果表明:6个非洲菊品种的花粉形态、花粉数量和花粉活力均存在差异。‘玲珑’的花粉粒最大,‘大雪菊’的花粉粒最小;‘云南红’花粉数量最多,‘玲珑’花粉数量最低;用花粉离体萌发法测定不同时期（初开、半开、盛开期）和不同温度下（5, 15, 25, 35 ℃）的花粉活力范围分别为2.75%～33.54%和0.37%～34.62%。系统聚类法以花粉粒粒长和花粉粒直径聚类,在组间距离为25处,6个非洲菊品种被划分为二大类,第一大类包括‘大雪菊’、‘拉丝’、‘香槟’、‘云南红’和‘紫霞’,第二类中的‘玲珑’单独聚成1类。     

花粉管通道及子房注射法转化Anti-TrxS基因

以 1 3个小麦品种 (品系 )的植株体为受体材料 ,用花粉管通道及子房注射法进行了硫氧还蛋白反义基因 (Anti TrxS)的遗传转化。花粉管通道法共处理小花 2 0 36朵 ,收获T0 种子1 61 6粒 ,结实率为 79.4% ,将T0 种子大田点播成株行 ,T1 共出苗 1 42 4棵 ,出苗率为 88.1 %。对T1 苗按品种和处理组合的方式进行抽样检测 ,抽样株系取 1 0个单株分别提取叶片基因组DNA ,然后将单株叶片DNA等量混合 ,进行株系基因组DNA的PCR检测。检测结果为 30个株系中有 1 6个株系呈阳性反应。子房注射法共转化豫麦 49号、豫麦 70号、豫麦 1 8号、郑新 991、95 5 1 9五个小麦品种 (品系 )的小花 1 2 0 6朵 ,收获种子 89粒 ,结实率为 7.4% ,T1 共出苗 41棵 ,出苗率为 46.1 %。     

番荔枝开花生物学与人工授粉研究

对三年生番荔枝（Ancnona squamosa L.)实生树的开花生物学和人工授粉进行了研究并发现；番荔枝的花有两荔异熟现象，人工授粉能提高座果率，简便而有效的方法是用毛笔直接从树上花药自然裂开的花上聚花粉并立即授在花药没裂开的花上，授粉后两周的座果率达87．9％，授 在花药裂开的花上，座果率为5．3％，与对照照座果率4．4％没有区别，说明花药裂开柱头容受性完全消失，花药裂开时间与品种特有关，目前，广东栽培的番荔枝分为花药早上裂开和傍开两种类型，这两种类型的不同品种之间授粉也能提高座果率，授粉后两周的座果率为83．3％。说明花裂开关12h柱头容受性仍完全正常。     

远缘和失活花粉蒙导核桃无融合生殖的研究

通过去雄和雌花套袋隔离,用油松花粉和失活核桃花粉对核桃3 个优良品种13个单株的雌花进行蒙导,结果表明:失活花粉蒙导,可明显提高核桃的无融合生殖率,油松花粉蒙导对核桃无融合生殖的影响与对照相近。     

The pollination of zygogynum (winteraceae) by a moth, sabatinca (micropterigidae): an ancient association?

The primitive and vesselless angiosperm Zygogynum (Winteraceae), which is restricted to New Caledonia, is pollinated by a moth, Sabatinca (Micropterigidae). Fossil records of both the moth and the plant families extend to the Early Cretaceous. Adult Sabatinca have grinding mandibles and usually feed on the spores of ferns and on pollen. The insects use the flowers as mating sites and eat the pollen which is immersed in a dense pollenkitt. This mode of pollination in which flowers serve as mating and feeding stations with floral odors acting as cues may have been common in the early evolution of flowering plants.     

Eocene angiosperm flowers

Collections of well-preserved angiosperm flowers from the Middle Eocene of southeastern North America include a variety of morphological types. The first of these specimens to be studied extensively, a catkin, has yielded a great deal of structural information. Floral morphology, pollen morphology, and the nature of the peltate scales suggest that this catkin is allied with extant genera of the Juglandaceae. This confirms the antiquity of some of the diagnostic floral and pollen features found in extant genera of the Juglandaceae and the importance of structural information available from fossil angiosperm flowers.