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.     

悬铃木花粉生活力及贮藏力的研究

以30~40年生悬铃木(Platanus acerifolia)的花粉为试材,研究了不同培养基对其萌发的作用,同时探讨了不同贮藏条件和贮藏时间对花粉生活力的影响。结果表明:悬铃木花粉在15%蔗糖 0.01%硼酸的培养基上培养24 h后萌发率最高;附加琼脂的固体培养基对花粉的萌发影响不大;50 mg/L的赤霉素对悬铃木花粉的萌发没有明显的抑制或促进作用;花粉干燥后在低温4℃下贮藏能保持较长的生活力,比未经干燥25℃和4℃下贮藏分别长35 d和20 d。     

杜鹃红山茶花粉萌发力及贮藏耐性的研究

以2～3年生嫁接的杜鹃红山茶(Camellia azalea)花粉为实验材料,研究了不同培养基、不同培养温度对其萌发的影响,同时探讨了不同贮藏条件和贮藏时间下花粉生活力的差异。结果表明:杜鹃红山茶花粉在不同培养时间下其萌发率呈抛物线型,花粉在15%蔗糖+0.02%硼酸的培养基上萌发率最高,30℃的培养温度比25℃、20℃更适合杜鹃红山茶花粉萌发。-20℃冷冻保存和液氮保存都是适合杜鹃红山茶花粉长期保存的方式。     

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.     

柑桔种间体细胞杂种的花粉特性及贮藏研究

对粗柠檬与“哈姆林”甜橙种间体细胞杂种的花粉特性(形态、花粉量、生活力等)进行了观察、检测,并于-20℃的低温条件下开展了贮藏试验。结果表明：花粉离体萌发的适宜培养基为0．8％琼脂 16％蔗糖 10mg／kg硼酸,萌发率为15．31％,其生活力介于两亲本之间,可作为杂交亲本进一步被利用。贮藏试验结果显示：以真空、干燥(CaCl2或硅胶作干燥剂)贮藏花粉的效果较好。授粉试验证明,贮藏花粉与新鲜花粉的座果率差异不显著,说明低温、真空和干燥是贮藏粗柠檬与“哈姆林”甜橙种间体细胞杂种花粉的较适条件。     

百合不同杂交系品种花粉贮藏特性分析

百合花粉贮藏是解决育种过程中花期不遇以及种质资源保存的重要环节,该试验以亚洲百合、东方百合和OT杂种系列的12个品种为材料,筛选出适合大部分品种花粉萌发的培养基及萌发率的观测时间,探讨花蕾发育时期[完全显色(-1级)、2/3显色(-2级)]、花粉收集后处理方式[离心管(处理Ⅰ)、离心管口加棉花(处理Ⅱ)、离心管口加棉花和管底添加干燥剂(处理Ⅲ)]、贮藏温度(常温、4℃、-20℃和-80℃)对花粉活力的影响。结果显示:(1)5%蔗糖+100(150)mg/L硼酸+30(50)mg/L氯化钙为适合大部分品种花粉萌发的液体培养基配方,百合花粉培养24h后测定萌发率为宜。(2)-1级花粉的萌发率比-2级的高且保持生命力的时间更长,如‘Tresor’-1级新鲜花粉的萌发率可达到83.2%,但其-2级只有21%。常温条件最不利于花粉保存,20d时大部分花粉萌发率为0;4℃与-20℃下较利于花粉短期贮藏且差别不显著。(3)经过4℃、120d贮藏,亚洲百合4个品种花粉萌发率最低能保持24.7%,最高能有55.9%左右;2个东方百合品种4℃下花粉萌发率为6.8%～12.7%;花粉在-80℃条件能较长时间保持活力,亚洲百合和东方百合花粉萌发率分别能保持26.7%～61.9%和7.1%～16.2%。(4)各个品种在不同温度条件下,大部分在处理Ⅲ下花粉萌发率较其他两种处理稍高。因此,-80℃结合在离心管口加棉花和管底添加干燥剂(处理Ⅲ)适合百合花粉的长期贮藏。     

垂丝紫荆花粉贮藏及生活力研究

为进行紫荆杂交育种和开发利用,以垂丝紫荆花粉为试材,利用离体培养法、3种染色法（醋酸洋红、TTC和碘-碘化钾染色）对花粉生活力进行测定,并分析不同贮藏温度和时间对花粉萌发的影响。结果显示,培养基中添加蔗糖和硼酸对花粉的萌发有促进作用,垂丝紫荆花粉萌发的适宜培养基为120 g/L蔗糖+40 mg/L硼酸,花粉萌发率达86.23%;醋酸洋红染色法适宜快速测定垂丝紫荆花粉生活力;垂丝紫荆花粉最佳的贮藏温度为 -196 ℃,经济的贮藏方法为-20 ℃。     

风信子花粉萌发及贮藏性研究

以20个风信子品种为材料,采用液体培养法研究了培养基组成、培养温度、贮藏温度和时间对花粉萌发特性的影响.结果表明:(1)适应风信子花粉萌发的培养基和温度因品种的不同而有差异,'安娜玛丽'品种为蔗糖100 g·L-1+H3BO3 20 mg·L-1+CaCl2 30 mg·L-1,15℃;'阿姆斯特丹'为蔗糖100 g·L-1+H3BO3 20 mg·L-1+CaCl2 30 mg·L-1,20℃;'奥斯塔'为蔗糖100 g·L-1+H3BO3 30 mg·L-1+CaCl2 30 mg·L-1,25℃.(2)不同品种风信子花粉萌发率差别较大,最高的'尉天蓝夹克'高达84.67%,最低的'爱丽斯'仅为10.71%,其余品种介于二者之间.(3)风信子花粉生活力随贮藏时间的延长而下降,'希腊之神'和'奥斯塔'花粉生活力在室温条件下贮藏9 d时已为0或接近0;在4℃和-20℃低温条件下,两品种贮藏12 d的花粉生活力仍大于20%.可见,不同风信子品种花粉萌发及贮藏条件不尽相同,在生产实践中应分别筛选,区别对待.     

花序开放程度、栽培温度和贮藏条件对菊花品种‘钟山金阳’花粉萌发的影响

采用离体培养法和杂交实验法,以菊花品种‘钟山金阳’(Chrysanthemum morifolium‘Zhongshanjinyang’)为实验材料,比较了不同的花序开放程度(花序开放天数和散粉阶段)、栽培温度和贮藏条件对其花粉萌发的影响。离体培养结果表明:在花序开放的第2至第7天花粉萌发率为22.6%~17.3%,第9天为7.7%,第11天仅为2.8%;在散粉的第1阶段(第1和第2轮管状花散粉)和第2阶段(第3和第4轮管状花散粉)花粉萌发率分别为19.5%和17.8%,第3阶段(全部管状花散粉)花粉萌发率仅为9.4%,表明随花序的开放和散粉阶段的延续,花粉萌发率均呈逐渐降低的趋势。在昼/夜温度5℃/0℃、10℃/5℃、15℃/10℃、20℃/15℃、25℃/20℃和30℃/25℃条件下栽培一定时间,其花粉萌发率和花粉管长度均有明显差异;其中,10℃/5℃栽培组培养4.0 h的花粉萌发率最高(23.0%),而30℃/25℃栽培组培养0.5 h的花粉萌发率最低(1.2%);15℃/10℃和20℃/15℃栽培组培养4.0 h的花粉管长度较长(分别为144.4和146.1μm),而30℃/25℃栽培组培养0.5 h的花粉管长度最短(38.3μm)。在不同贮藏温度下[4℃、-20℃和室温(约25℃)],新鲜和干燥花粉的萌发率均随贮藏时间的延长逐渐下降,但降幅存在明显差异;其中,新鲜花粉贮藏12 d后花粉萌发率从21.4%降至5.0%以下,干燥花粉贮藏26 d后花粉萌发率降至5.0%以下;总体上看,干燥花粉的萌发率和贮藏时间均高于新鲜花粉,以-20℃条件下贮藏的干燥花粉萌发率最高且可贮藏至50 d以内。杂交实验结果显示:用不同栽培温度下的品种‘钟山金阳’的花粉对品种‘钟山粉碟’(‘Zhongshanfendie’)进行人工授粉,在柱头上花粉萌发数差异明显;其中,10℃/5℃栽培组的花粉萌发数最多(55.5),30℃/25℃栽培组的花粉萌发数最少(8.8),且二者间差异显著(P0.05)。综合分析结果表明:花序开放天数、散粉阶段、栽培温度及贮藏条件对菊花品种‘钟山金阳’的花粉萌发率均有明显影响。根据研究结果,建议菊花品种‘钟山金阳’花粉的最佳采集时期为花序开放的7 d内且为第1至第4轮管状花散粉阶段,栽培温度应维持在10℃左右,而且采集的花粉应置于-20℃干燥条件下贮藏。     

紫花含笑（♀）、灰岩含笑（♂）及其杂种F1代花粉萌发试验研究

对紫花含笑(Michelia crassipes)、灰岩含笑(M.calcicola)及其杂种F1代花粉生活力进行了研究,为基于紫花含笑和灰岩含笑杂种F1代的含笑属观赏植物新品种培育与种质创新提供科学数据及研究资料.研究发现,亲本(紫花含笑和灰岩含笑)新鲜花粉萌发率均可达90％以上,杂种F1代花粉萌发率从38％到79％不等,平均为57.7％,低于双亲.亲本及其杂种F1代花粉萌发的最适温度为25℃,温度过高花粉管的伸长受到抑制,并导致花粉管顶端破裂.亲本及多数杂种F1代的新鲜花粉在100 g/L和150 g/L的蔗糖浓度下萌发率都较高;经-20℃贮藏后的花粉对蔗糖浓度的敏感性要高于新鲜花粉.杂种F1代及其亲本的花粉在离体培养中均会出现双萌发管现象.番红染料对液体培养基中的花粉有致死和染色作用,有利于统计杂种F1代及其亲本的花粉萌发率.     

Seasonal distribution of airborne pollen in the coastal plain of Israel

Airborne pollen was monitored in three major urban centers of the coastal plain of Israel during the years 1993–1995. Results show spatial and temporal variations among the three sites. Altogether, the number of identified species was rather low. Ornamental trees (Cupressaceae,Pinus, Olea, Casuarina, Ceratonia) and grasses, have constituted the main source of the pollen rain. A substantial contribution of the wild plants of the region was restricted toParietaria, Urtica, Mercurialis, Artemisia, grasses and members of the Chenopodiaceae and Amaranthaceae.     

Airborne pollen calendar of the central region of Bursa (Turkey)

This report describes qualitatively and quantitatively the level of pollen in the atmosphere in the central region of Bursa. Turkey. In 1991, the season of maximum pollen concentration was from April to June, with a prevalence of arboreal pollen during the initial months, and of pollen from herbaceous plants in the latter months. During the year of research, 24 taxa of arboreal and 12 taxa of herbaceous pollen grains were collected and identified. In the region investigatedPinus, Cupressaceae/Taxaceae,Abies nordmanniana, Platanus orientalis, Olea europaea, Gramineae, Urticaceae, Chenopodiaceae/Amaranthaceae,Artemisia and Compositae were responsible for the greatest amounts of pollen. Some important allergenic pollens such asOlea europaea, Gramineae and Urticaceae were also found in high concentration. In this study, a pollen calendar for the region is presented.     

Seasonal distribution of pollen in the atmosphere of melbourne: an airborne pollen calendar

Environmental monitoring of pollen grains in the atmosphere of Melbourne has been achieved using Burkard volumetric traps. Twenty-two families of flowering plants and confiers were identified in the pollen counts. About 62% of these pollen grains belonged to trees, 20% to grasses and 9% to herbs and weedy plants. During spring and summer, the atmosphere contained about 70% of the total annual pollen count. Tree pollen, predominantly elm and cypress, occurred abundantly in late winter and spring, with grass pollen predominantly in spring and early summer. These three types of pollen grains occurred in significant amounts, together accounting for more than 60% of the total annual catch. A seasonal incidence chart (pollen calendar) for Melbourne based on 2 years observation has been constructed. This pollen calendar is useful in identifying sources of allergies against particular seasonal airborne pollen types. Comparison of the time of occurrence of a particular pollen type using the pollen calendar and the time of allergic symptoms, can lead to accurate diagnosis and preventive measures being taken. This study has confirmed that grass pollen is the major source of allergenic pollen in the external environment triggering hay fever and allergic asthma in spring and early summer in Melbourne, Australia.     

A preliminary survey of airborne pollen in Madras City

The atmospheric pollen of Madras city was surveyed during a 1-year period (January–December 1995) with a vertical cylinder trap. A total of 32 pollen types were identified, among which nine were present throughout the year. These belonged to Poaceae,Casuarina equisetifolia Foster and Foster f.,Prosopis juliflora (SW.) DC.,Acalypha indica L.,Parthenium hysterophorus L., Cyperaceae,Cocos nucifera L., Amaranthaceae, andTypha angustata Borry and Chaub. Among the identified pollen, 61.05% belonged to trees, 21.01% to grasses, 11.65% to herbs and 6.27% to shrubs. Anemophilous pollen contributed about 52.87% to the total while entomophilous and amphiphilous pollen contributed 38.89 and 8.22%, respectively. Pollen belonging to Poaceae were found to be most predominant in the air of Madras city followed byCasuarina equisetifolia andProsopis juliflora.     

Effects of pollen competitive environment on pollen performance in Mirabilis jalapa (Nyctaginaceae)

 We examined the influence of pollen competitive environment on pollen performance in Mirabilis jalapa. We used the number of pollen grains and the number of pollen tubes per pistil as measures of pollen competition. Pollen germination, pollen tube penetration into the style, and pollen tube growth rates were used as measures of pollen performance. All three measures of pollen performance were affected by the competitive environment. Pollen germination was greatest at intermediate pollen load sizes. The percentage of germinated pollen grains that penetrated the stigma and grew into the style decreased with pollen load size. Pollen tube growth rate in the style was greater and more variable with larger numbers of pollen tubes in the style. Controlling for the degree of selection at the stigma indicated that pollen-pollen or pollen-style interactions were the likely causes of increased growth rates. Received: 28 October 1996 / Revision accepted: 24 January 1997     

Pollen selection — past,present and future

 A series of studies, recently reviewed, has established that approximately 60% of the structural genes which are expressed in the sporophytic portion of the angiosperm life cycle are also expressed and exposed to selection in the pollen. Given the haploidy and large population sizes of pollen grains, a substantial portion of the sporophytic genome could thus be periodically exposed to a bacterial type of mass screening. This extraordinary possibility is often subject to some skepticism which may, of course, be justified. However, recent attempts to apply models appear to be inappropriate in this context, in part because these attempts overlook an important source of genetic variation, and also because they assume fixed values for selection and fitness. More recently, studies of pollen/pollen interactions have suggested that what Linskens termed the ”programic phase” may represent an arena for important, and largely unexplored phenomena, some of which are discussed here. Received: 3 June 1996 / Revision accepted: 26 July 1996     

Effects of pollination intensity on the vigor of the sporophytic and gametophytic generation of Cucurbita texana

 We examined the effects of pollen competition (pollen load size) on sporophytic vigor and gametophytic performance in Cucurbita texana, a wild gourd, while controlling for alternative interpretations of the data. Under field conditions we compared the vigor of progeny produced from large and small pollen loads and examined the in vitro performance of the pollen produced by the progeny. We found that the progeny from large pollen loads germinated faster and had a greater reproductive output (male flowers and fruits) than progeny produced from small pollen loads. In addition, we found that the pollen produced on plants derived from large pollen loads grew faster in vitro than the pollen produced on plants derived from small pollen loads. These findings indicate that pollen competition affects the performance of the resulting sporophytic generation and the microgametophytes they produce. Received: 26 January 1997 / Revision accepted: 25 June 1997     

In vitro maturation and germination of <Emphasis Type="Italic">Orychophragmus violaceus</Emphasis> microspores

Microspores cultured in vitro can be regarded as a system to study gene regulation, cell fate determination and cell differentiation during pollen development as well as an alternative method of genetic transformation in plants. In our study, pollen development and viability in Orychophragmus violaceus in vivo were determined and then pollen from the late unicellular stage was cultured in vitro. MS liquid medium + White vitamins + 2% (V/V) coconut milk + 0.5 M maltose, pH = 7.0 was the most appropriate for in vitro culture of Orychophragmus violaceus microspores. With this medium, the rates of in maturation and germination were 19.3% and 4.7%, respectively. Liquid medium with 0.6 M maltose + 1.6 mM boric acid + 2.9 mM Ca(NO₃)₂ + 29.6 μM vitamin B1, pH = 7.0 was optimal for germination of pollen matured in vivo. The rate of germination was 70.7%. Pollen matured in vitro cultured in similar medium exhibited a rate of germination of 62.7%. Hence, the experimental study showed that in vitro maturation of microspores is feasible and this experimental system can be applied to further theoretical and practical research.     

Analysis of liquid extracts from tree and grass pollens by capillary electromigration methods

Capillary electromigration methods, zone electrophoresis (CZE), micellar electrokinetic chromatography (CMEKC) and isotachophoresis (CITP), have been used for analysis of water and water-buffer extracts from tree-common birch (Betula verrucosa) and grass-orchardgrass (Dactylis glomerata) pollen samples. Water extracts were analyzed by CZE using acetic acid as background electrolyte (BGE), by CMEKC in tris-phosphate BGE with anionic detergent sodium dodecyl sulfate (SDS) micellar pseudophase (TP-SDS) and by CITP in cationic mode with leading/terminating cations K+/BALA+ (beta-alanine (BALA)) and in anionic mode with leading/terminating anions Cl-/MES- (2-(N-morpholino)ethanesulphonic acid (MES)). Moreover, acetic acid extracts were analyzed by CZE using acetic acid as BGE, and alkaline water-SDS-buffer extracts were analyzed by CMEKC using TP-SDS as BGE. Extracted amounts of pollen allergens and other UV-absorbing compounds and the number of resolved components were evaluated from CZE, CMEKC and CITP analyses of the liquid extracts. Larger amounts of UV-absorbing material were found in the water-buffer pollen extracts than in the water extracts. More UV-absorbing material was found in all extracts from D. glomerata pollen than in relevant extracts from B. verrucosa pollen. It was found by CITP that the extracted amounts of anionic components and their number were much higher than those of cationic components. Concentrations of some inorganic ions (e.g. Cl-, K+, Na+, Ca2+) in pollen samples were also determined by CITP.     

Secondary pollen carryover by ants in a natural population of Scleranthus perennis (Caryophyllaceae)

Summary Secondary pollen carryover is defined as the process whereby a pollinator receives previously deposited pollen grains when visiting a flower and transfers them into a new (secondary) carryover sequence. The secondary pollen carryover in a system of ants, Formica rufibarbis, visiting Scleranthus perennis (Caryophyllaceae) was studied using fluorescent dyes as pollen analogues. The mean secondary carryover was found to be 1.2 flowers compared with 4.5 flowers for the primary carryover. The number of dye grains deposited per flower visited is lower and the frequency of zero deposition is higher in the secondary carryover sequence than in the primary.