桃花粉离体萌发和花粉管生长特性研究

采用花粉离体萌发法研究不同培养基组分和培养条件对桃花粉萌发和花粉管生长的影响,同时对不同贮藏温度下的桃花粉寿命进行研究.结果表明:固体培养基与液体培养基对桃的花粉萌发率和花粉管长度影响差异不显著;10%蔗糖是大多数桃品种花粉的最适萌发条件;硼能提高桃花粉的萌发率,但对花粉管的生长没有促进作用;桃花粉在20℃～25℃的培养温度下萌发率最高,花粉管最长;桃花粉萌发率和花粉管长度在培养前3 h内上升最快,3～5 h上升趋势减弱,5 h后基本停止;随着贮藏温度的升高和贮藏时间的延长,花粉生活力呈降低的趋势.     

栽培稻与其野生近缘种的可交配性研究

通过人工授粉方法研究栽培稻与二倍体和四倍体野生稻之间的可交配性.以栽培稻为对照,用光学显微镜观察不同野生稻花粉在同一栽培种柱头上的萌发生长情况.结果表明,在栽培稻柱头上普通野生稻(AA)花粉萌发最好,与对照萌发情况相近.药用野生稻(CC)萌发差,表现为柱头上花粉附着量少,开始萌发时间迟,萌发量少,花粉管扭曲、缠绕、伸长慢等.四倍体野生稻未观察到有萌发现象.说明普通野生稻与栽培稻亲缘关系近,可交配性好;药用野生稻与栽培稻可交配性差;四倍体野生稻与栽培稻可交配性极差.由此推断,转基因水稻与普通野生稻通过花粉途径发生基因漂移的可能性很大,而与药用野生稻和其他基因组野生稻发生基因漂移的可能性很小.     

沙田柚花粉低温贮藏的研究

研究了脱水时间 ,化冻方式和培养基对沙田柚 ( Citrus grandis var. shatinyu Hort. )花粉低温贮藏后萌发率的影响。结果表明 :贮藏 3个月 ,6个月期间 ,脱水 50 min的花粉萌发率最高 ;沙田柚花粉低温贮藏的最适含水量为 13.5%。沙田柚花粉适合快速化冻法。在 4种培养基中 ,萌发率无显著差异 ,但花粉管生长不一致     

In vitro pollen germination in Hypericum perforatum L. and Hypericum rumeliacum Boiss

In vitro pollen germination and pollen tube growth investigations are valuable tools used in identification of the effects of environmental factors and genotypic differences on pollen viability, pollen germination and tube elongation. In this study pollen viability, in vitro pollen germination capacity, abnormality ratios and tube length in germinated pollens of Hypericum perforatum L. and H. rumeliacum Boiss. were investigated. Both of these species has spheroid-shaped and tricolporate pollen grains. The diameters of Hypericum perforatum and H. rumeliacum pollens were found as 24 +/- 3 microm and 19 +/- 2 microm, respectively. Pollen viability of H. perforatum and H. rumeliacum was found as 83% and 72%, respectively. The germination percentages were found as 12.85% for H. perforatum and 64.42% for H. rumeliacurm. Tube lengths in germinated pollens of both taxa were measured approximately as 95.25 +/- 38 microm in H. perforatum and 165.92 +/- 53 microm in H. rumeliacium 4 h after inoculation. In germinated pollen grains of H. perlbratum and H. rumeliacumn abnormality percentages were determined as 13.23% and 43.97%, respectively. In germinated pollens of these two species, highly significant (P < 0.00001) differences in in vitro germination percents and abnormality percents were observed. Abnormalities such as swollen tube tip, branched tube, spiralled tube and excessive tube formation were observed in pollen tubes. The results of this study showed that there were obvious differences in pollen germinability between these two species growing under the same environmental conditions.     

瑞香狼毒对青藏高原东部高寒草甸主要物种花粉萌发和种子结实的花粉化感效应

花粉化感是一类特殊的化感作用,能够抑制其它物种的花粉萌发和种子结实。研究了瑞香狼毒(Stellera chamaejasme)花粉水浸提液对其它物种花粉萌发和种子结实的潜在化感抑制作用,包括:在实验室中,用一系列浓度的狼毒花粉水浸提液对与它同花期的其它6个物种(秦艽(Gentiana macrophylla Pall.var.fetissowii),湿生扁蕾(Gentianopsis paludosa(Hook.f.)Ma var.paludosa),鳞叶龙胆(Gentiana squarrosa Ledeb.),椭圆叶花锚(Halenia elliptica D.Don var.elliptica),高原毛茛(Ranunculustanguticus(Maxim.)Ovcz.var.tanguticus)和鹅绒委陵菜(Potentilla anserina L.var.anserina))以及自身花粉进行测试,测定花粉萌发率;在野外,在其它4个物种(秦艽,湿生扁蕾,鳞叶龙胆和椭圆叶花锚)的柱头上施用上述浓度的狼毒花粉水浸提液,观察种子结实率。实验室的花粉萌发试验证明,狼毒花粉对自身花粉萌发没有自毒作用,而其它受试的所有物种的花粉萌发率随着狼毒花粉浸提液浓度的增加呈显著地非线性降低。大约3个狼毒花粉的浸提液就可以抑制受试的多数物种的50%的花粉萌发。在野外试验中,发现受试的4个物种种子结实率随狼毒花粉浸提液浓度的增加呈显著地非线性降低。狼毒可能通过花粉化感对其周围其它物种的有性繁殖存在抑制作用,但其它物种可能通过花期在季节或昼夜上的分异避免受到狼毒花粉化感作用的影响,或者通过无性繁殖来维持种群繁衍。     

阿拉善荒漠驼蹄瓣属7种植物的花粉形态研究

用扫描电镜对阿拉善荒漠驼蹄瓣属(ZygophyllumL.)7种植物的花粉形态特征进行了观察分析.结果表明,在扫描电镜下,每种植物花粉粒的表面纹饰、萌发孔类型等性状符合驼蹄瓣属的主要特征;而花粉粒的大小、P/E值等细微特征存在明显差异.     

景宁木兰花粉萌发与贮藏特性研究

以景宁木兰的花粉为试材,采用花粉离体培养法,用单因子与正交试验研究不同浓度蔗糖、H3BO3、CaCl2所组成的基本培养基对景宁木兰花粉萌发的影响,同时探讨不同贮藏条件和贮藏时间对花粉活力的影响。结果表明:景宁木兰在30 g·L-1蔗糖+200 mg·L-1H3BO3+200 mg·L-1CaCl2的液体培养基上萌发率最高(74.56%)。低温条件下有利于景宁木兰花粉生活力的保持,在-80℃条件下,花粉生活力下降较慢,并且随着贮藏时间的增加,经过硅胶干燥的花粉的活力明显高于湿润花粉的活力。     

梨远缘花粉原位萌发及生长特性

应用荧光标记方法对梨远缘花粉在‘丰水’和‘噢嗄二十世纪’柱头上萌发及花粉管生长特性进行观察,结果表明:(1)梨远缘花粉均能在柱头上萌发,但其萌发率不同,授粉后24 h,在‘丰水’柱头上‘红叶桃’花粉萌发率最高,达62.8%,而‘盖县大李’花粉萌发率仅为12.0%,各种远缘花粉在‘丰水’柱头萌发率均高于‘噢嗄二十世纪’柱头。(2)各种远缘花粉管在梨柱头或花柱内生长情况也有差异,‘红叶桃’等核果类花粉管在梨柱头上均表现为扭曲、盘绕等现象,不能穿过柱头;‘红星’和‘红富士’花粉管虽然有少量穿过柱头,但不能进一步在花柱内生长,表现为扭曲变形、先端膨大等不亲和性现象。因此,梨与远缘果树杂交不亲和在柱头上就已发生,这与梨自交不亲和反应发生在花柱内的现象不同。     

温度对桃离体花药散粉及花粉萌发的影响

以目前生产栽培较多的‘湖景蜜露’、‘霞晖6号’和‘白凤’3个桃品种为试材,连续2年调查了不同温度处理下花药失水率、花药散粉时间以及花粉离体萌发特性等变化。结果表明：桃花药于相对低温条件下散粉失水率较低,随散粉温度升高失水率相应上升;花药开裂所需时间与处理温度呈相反趋势;3个品种花粉离体萌发率随散粉温度的升高而下降。离体花药在超过30℃的温度条件下散出的花粉在萌发过程中出现花粉管变短、花粉瘪小的概率增多的现象,表明高温促使花药脱水和散粉加快,但降低了花粉活力。在桃树花期以及制备花粉时外界环境温度应控制在30℃以下。     

Stigmatic RNase in calamondin (Citrus reticulata var. austera x Fortunella sp.)

In calamondin. which is self-compatible, ribonuclease (RNase) activity was found in the stigmatic diffusate. Tissue print experiments using calamondin styles demonstrated that most of the RNase is localized in the stigma. Stigmatic RNase activity was monitored at different developmental stages of the flower and was found to peak at anthesis. An SDS-PAGE-zymogram indicated the molecular mass of this RNase to be 24 kDa. In vitro germination of calamondin pollen showed a higher percentage of germination in the presence of diffusate from one stigma than in the control. However, diffusates from 3.5 and 7 stigmata per 100 μl aliquots of growth medium, exhibiting 15. 25 and 35 units ml⁻¹ RNase activity, respectively, had successively stronger inhibition effects on the percentage of germination. Diffusate from 7 stigmata inhibited pollen tube elongation, as well as pollen germination. Both the 24-kDa Stigmatic RNase and RNase TI significantly inhibited pollen germination and pollen tube elongation. In pollen tubes treated with either the 24-kDa stigmatic RNase or RNase TI, considerable deposition of callose was observed, as compared to the control which had only a thin callosic cell wall.     

培养条件及贮藏温度和时间对木麻黄花粉萌发率的影响

用离体培养的方法研究了不同蔗糖、硼酸浓度,以及不同贮藏温度和贮藏时间对木麻黄(Casuarina)花粉萌发的影响.结果表明:15%的蔗糖是木麻黄花粉萌发的最佳浓度;在15%蔗糖培养基上添加硼酸显著促进木麻黄花粉萌发,250 mg kg-1硼酸是木麻黄花粉萌发的最佳浓度;添加了琼脂的固体培养基更有利于木麻黄花粉萌发;在常温下木麻黄生活力丧失很快,但低温下花粉的萌发力可保持较长时间.     

曼地亚红豆杉‘Hicksii’花粉活力检测条件优化和适宜诸藏温度分析

采用单因素实验设计对适宜于曼地亚红豆杉‘Hicksii’(Taxus media‘Hicksii')花粉活力检测的TTC染色法和离体培养法的实验条件进行了选择,并采用优化条件研究了在25℃～-196℃条件下储藏13周花粉活力的变化.结果表明:采用TTC染色法测定的花粉活力均高于离体培养法.在TTC染色法的3个影响因素(染液pH、TTC浓度和染色温度)中,染液pH对检测结果有极显著影响,而染色温度和TTC浓度则无显著影响,但温度对染色速率有影响.在离体培养法的3个影响因素(培养基中蔗糖添加量、H3BO3和Ca(NO3)2浓度及培养温度)中,蔗糖添加量对检测结果有极显著影响,在含质量体积分数15％蔗糖的培养基上花粉活力最高,而在含质量体积分数20％和25％蔗糖的培养基上花粉均不能萌发;在含100和200 mg ·L-1H3BO3的培养基中添加200 mg·L-1Ca(NO3)2均能显著提高花粉活力;培养温度对花粉萌发速率有影响但对花粉活力没有明显影响.TTC染色法的最优检测条件为:用5.0g·L-1TTC染液(pH 7.0)在35℃下染色2.0h;离体培养法的最优检测条件为:用含质量体积分数15％蔗糖、100 mg·L-1H3BO3和200 mg·L-1Ca(NO3)2的培养基暗培养4d.在25℃、4℃、0℃、-20℃、-80℃和-196℃条件下储藏13周,‘Hicksii'花粉活力和保持时间有明显差异,其中,于-80℃和-196℃储藏3d 花粉就丧失活力;于25℃和-20℃储藏7周、4 ℃储藏10周,花粉仍有一定的活力;而在0℃条件下花粉活力最高,且储藏11周花粉仍有活力.推测曼地亚红豆杉‘Hicksii’花粉对低温的抗性较差,0℃为其适宜的储藏温度.     

Differences in in vitro pollen germination and pollen tube growth of cotton cultivars in response to high temperature

* BACKGROUND AND AIMS: High-temperature environments with >30 degrees C during flowering reduce boll retention and yield in cotton. Therefore, identification of cotton cultivars with high-temperature tolerance would be beneficial in both current and future climates. * METHODS: Response to temperature (10-45 degrees C at 5 degrees C intervals) of pollen germination and pollen tube growth was quantified, and their relationship to cell membrane thermostability was studied in 12 cultivars. A principal component analysis was carried out to classify the genotypes for temperature tolerance. * KEY RESULTS: Pollen germination and pollen tube length of the cultivars ranged from 20 to 60 % and 411 to 903 microm, respectively. A modified bilinear model best described the response to temperature of pollen germination and pollen tube length. Cultivar variation existed for cardinal temperatures (T(min), T(opt) and T(max)) of pollen germination percentage and pollen tube growth. Mean cardinal temperatures calculated from the bilinear model for the 12 cultivars were 15.0, 31.8 and 43.3 degrees C for pollen germination and 11.9, 28.6 and 42.9 degrees C for pollen tube length. No significant correlations were found between pollen parameters and leaf membrane thermostability. Cultivars were classified into four groups based on principal component analysis. * CONCLUSIONS: Based on principal component analysis, it is concluded that higher pollen germination percentages and longer pollen tubes under optimum conditions and with optimum temperatures above 32 degrees C for pollen germination would indicate tolerance to high temperature.     

青篱柴通过促进亲和花粉生长而提高传粉精确性

异型花柱植物的适应意义在于提高亲和花粉的传递, 从而促进异交, 但是有不少研究发现柱头上落置了大量不亲和花粉。目前, 很少有人研究柱头是否有利于亲和花粉的萌发和花粉管伸长, 以及通过去雄处理排除花内和植株内不亲和花粉干扰从而验证二型花柱植物是否可以促进异交。本研究以亚麻科青篱柴属(Tirpitzia)的二型花柱植物青篱柴(T. sinensis)为研究对象, 分居群调查了青篱柴长、短柱型的植株数量, 测量不同柱型的花粉与柱头大小以及观察其表面纹饰, 测定不同开花时间长、短柱型的柱头活性与花粉活力, 统计自然状态下柱头上落置的不同表型花粉比例, 进一步统计花内、株内去雄和自然对照下柱头上落置的不同表型花粉比例, 计算型间、型内和混合授粉花粉管长度和花粉萌发率, 人工授粉检测其是否型内异交不亲和与自交不亲和。结果表明, 自然居群中长、短柱型青篱柴植株数量没有显著性差异; 短柱型青篱柴花粉体积显著大于长柱型, 且二者花粉表面纹饰不同, 但不同柱型的柱头表面积与表面纹饰无差异; 青篱柴开花第一天的花粉活力显著高于开花第二天, 而柱头活性在开花前两天无显著性差异; 自然状态下柱头上落置的不亲和花粉比例显著高于亲和花粉; 在长柱型青篱柴中, 花内和株内去雄显著提高了柱头上亲和花粉的落置比例; 柱头上授型内花粉, 其花粉萌发率和花粉管的长度都显著低于授型间花粉; 授粉结果表明青篱柴为型内异交不亲和与自交不亲和。二型花柱植物通过促进亲和花粉的萌发和花粉管的伸长而有利于型间授粉, 从而显著提高其传粉精确性。     

木兰科植物的人工杂交

采用常规人工杂交方法,在木兰科中进行了68个组合杂交试验。结果表明：花粉活力随种类不同有很大差异,人工授粉后结实率很高,小孢子败育不是木兰科植物自然结实率普遍低的主要原因。木兰亚属种间杂交均表现为亲和,含笑属有些种间杂交不亲和;属间杂交多不亲和,但红元宝二乔玉兰与金叶含笑和云南含笑的杂交完全亲和,结实率高达80％～100％,表明玉兰亚属和含笑属间有较近的亲缘关系;观光木与金叶含笑、云南含笑虽有较高的杂交结实率,但杂交种子不能萌发,支持观光木属成立。     

Screening for High-Temperature Tolerant Cotton Cultivars by Testing In Vitro Pollen Germination, Pollen Tube Growth and Boll Retention

With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major influence on crop production. In the cotton (Gossypium hirsutum L.)-growing areas of China, especially in the Yangtze River valley, unexpected periodic episodes of extreme heat stress usually occur in July and August, the peak time of cotton flowering and boll loading, resulting in lower boll set and lint yield. Breeding programs for screening high temperature-tolerant cotton germplasm and cultivars are urgent in order to stabilize yield in the current and future warmer weather conditions. In the present study, 14 cotton cultivars were quantified for in vitro pollen germination and pollen tube growth in response to temperatures ranging from 10 to 50 ℃ at 5 ℃ intervals. Different cotton genotypes varied in their in vitro pollen germination and pollen tube length responses to the different temperatures. Maximum pollen germination and pollen tube length ranged from 25.2% to 56.2% and from 414 to 682 μm, respectively.The average cardinal temperatures (Tmin, Topt, and Tmax) also varied among the 14 cultivars and were 11.8,27.3, and 42.7 ℃ for pollen germination and 11.8, 27.8, and 44.1 ℃ for maximum pollen tube length. Variations in boll retention and boll numbers per plant in field experiments were found for the 14 cotton cultivars and the boll retention and boll retained per plant on 20 August varied considerably in different years according to weather conditions. Boll retention on 20 August was highly correlated with maximum pollen germination (R2=0.84) and pollen tube length (R2=0.64). A screening method based on principle component analysis of the combination of pollen characteristics in an in vitro experiment and boll retention testing in the field environment was used in the present study and, as a result, the 14 cotton cultivars could be classified as tolerant, moderately tolerant, moderately susceptible and susceptible to high temperature.     

Pollen morphology and germination inNarcissus

Pollen grains of several species and varieties ofNarcissus were examined with a light microscope and a scanning electron microscope. Normal pollen grains were kidney- or spindle-shaped with a germination furrow and a reticulate structure similar to that of the pollen grains ofAmaryllis. Pollen grains germinated within 2 to 3 hr. Percentage of germination was dependent upon temperature and treatment. Pollen tubes grew in length up to 1,000 μm and branched occasionally or behaved in strange fashion. Fresh pollen grains germinated more in distilled water at lower temperature than in sucrose-aqueous medium. Both in the presence and in the absence of stigmatic exudate calcium increased the percentage of germination. Gibberellic acid, abscisic acid and coumarin inhibited the pollen germination. Plasmoptysis occurred in all species and in all media tested except in a medium containing coumarin without stigmatic exudates. Plasmoptysis did not seem to be induced by hypotonic medium alone. Pollen of high germination capacity showed a high percentage of plasmoptysis. Based on the results obtained, evolution and sterility of theNarcissus plant was discussed.     

梨花柱S-RNase对花粉管超微结构的影响

采用光学显微镜和透射电子显微镜研究了离体条件下不同品种梨花柱S—RNase对异花(亲和)及自花(不亲和)花粉萌发和花粉管生长及其超微结构的影响。结果表明,花柱S—RNase抑制不亲和花粉的萌发和花粉管的生长,对亲和花粉的萌发和花粉管的生长基本没有影响。花粉生长初期,亲和及不亲和花粉管超微结构相似;但培养24h以后,亲和花粉管中充满细胞质和细胞器,而不亲和花粉管中只有靠近花粉管前端有少量细胞质,细胞壁增厚,细胞壁与细胞质之间有一层胼胝质和电子透明区间隔。     

Morphological diversity and function of the stigma in Ficus species (Moraceae)

The stigma plays several roles such as pollen hydration and selection, and pollen tube nutrition. In the Ficus-fig wasp mutualism, stigmata have an additional, almost unknown, function by representing a physical interface for both plant and wasp reproduction. We used light and electron microscopy to compare the detailed morphology of the stigmata of nine Ficus species of different sections and with different pollination modes and sexual expressions. Figs were collected at the stage when the stigmata were receptive for pollination. Stigmata in actively pollinated monoecious species have well developed papillae concentrated on the adaxial surface exposed towards the fig cavity. Conversely, the passively pollinated monoecious species have the whole surface of the stigmata covered by somewhat smaller papillae. In both actively and passively pollinated monoecious species these features are consistent, irrespective of style length. In all actively pollinated gynodioecious species, the stigmata of pistillate flowers were tubular or infundibuliform whereas in almost all actively pollinated monoecious species (except F. racemosa) the stigmata were filiform, with one branch or two asymmetric branches. In gynodioecious species the short-styled flowers in “male” figs show a limited receptive surface with small papillae, while the stigmata of long-styled flowers in “female” figs are covered by papillae that extend down the sides of the style, increasing the stigmatic surface. In actively pollinated species, stigmata are cohesive, forming a common surface for pollen tube germination (= synstigma). The synstigma arrangement was quite variable: lax, cohesive or very cohesive, with entanglement by stigmatic papillae and stylar trichomes. Entanglement by stylar trichomes is common in gynodioecious species. The synstigma arrangement did not correlate with phylogeny or breeding system. This study is the first to report a very loose synstigma in actively pollinated monoecious Ficus species. Our analyses revealed that, in Ficus, the synstigma is functionally analogous to an extra-gynoecial compitum. Comparative studies will be required to test further hypotheses about the evolutionary determinants of such variation.     

Studies on Microspore Development in Liliaceous Plants III. Pollen Tube Development in Lily Pollens Cultured from the Uninucleate Microspore Stage

Uninucleate microspores of Lilium longiflorum isolated at theGi phase of the cell cycle were cultured on a solid nutrientmedium for 12 days. The typical pollens produced in the culturegerminated on a germination medium and developed a structureresembling a pollen tube. The elongating pollen tubes occasionallycontained dividing generative nuclei or two sperm nuclei. (Received September 29, 1980; Accepted November 25, 1980)