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1.
Cupressus arizonica pollen wall zonation and in vitro hydration 总被引:1,自引:0,他引:1
The structure of Cupressus arizonica pollen at different degrees of hydration was examined by using cytochemical staining and light (LM) and scanning electron
(SEM) microscopy. Most pollen grains are inaperturate and a minority are provided with an operculate pore enveloped by a concave
annulus. Intine consists of: 1) a thin polysaccharidic outer layer, 2) a large polysaccharidic middle layer that is spongy
and bordered by a mesh of large and branched fibrils, and 3) an inner cellulosic thick layer with callose concentrated on
the inner side, which forms a shell around the protoplast. The protoplast is egg-shaped with PAS positive cytoplasm and prominent
nucleus. Exine splits during hydration and is cast off according to three major steps: 1) the split opens like a mouth and
the underlying intine is expelled by swelling like a balloon, 2) the protoplast enveloped by the inner intine is sucked in
the outgrowing side, and 3) the backside of the intine gets rid of the exine shell. In water containing salts, exine is rapidly
released and the middle intine may expand up to break the outer layer, with disgregation of the spongy material and release
of the intine shell including the protoplast. In water lacking salts, the sporoderm hydration and breaking are negatively
influenced by the population effect. Pollen when air dried after the exine release become completely flat owing to disappearance
of the middle intine layer which may be restored by dipping pollen in water. The results are discussed in relation to the
functional potentialities of the sporoderm. 相似文献
2.
Chemical Composition and Biological Activities of Tunisian Cupressus arizonica Greene Essential Oils
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Amri Ismail Emilia Mancini Laura De Martino Lamia Hamrouni Mohsen Hanana Bassem Jamoussi Samia Gargouri Mariarosa Scognamiglio Vincenzo De Feo 《化学与生物多样性》2014,11(1):150-160
The chemical composition of the essential oils obtained by hydrodistillation of leaves, stems, and female cones of Cupressus arizonica Greene , grown in Tunisia, was studied by GC‐FID and GC/MS analyses. Altogether, 62 compounds were identified, 62 in the leaf oil, 19 in the cone oil, and 24 in the stem oil. The cone and stem oils were mainly composed by monoterpene hydrocarbons (96.6 and 85.2%, resp.). In the leaf oil, the total sesquiterpene fraction constituted 36.1% and that of the monoterpene hydrocarbons 33.8% of the total oil composition. The three oils were evaluated for their in vitro herbicidal activity by determining their influence on the germination and the shoot and root growth of the four weed species Sinapis arvensis L., Lolium rigidum Gaudin , Trifolium campestre Schreb ., and Phalaris canariensis L. At the highest doses tested (0.8 and 1.0 mg/ml), the leaf essential oil inhibited either totally or almost completely the seed germination and the shoot and root growth of S. arvensis and T. campestre. The oils were also tested for their antifungal activity; however, their effects on the fungal growth were statistically not significant. 相似文献
3.
Rehfeldt G 《American journal of botany》1997,84(2):190-200
Seedling populations of seven Cupressus taxa were compared in common gardens to assess relationships among taxa and to elucidate the genetic structure of three taxa with different distributions and demographics. Discriminant analyses of 15 quantitative traits separated C. sargentii and C. forbesii from taxa within the C. arizonica complex (C. arizonica, C. glabra, C. stephensonii, C. nevadensis, and C. montana); aligned a population of C. arizonica from Sierra de Arteaga, Mexico, with families of the same taxon from southwestern United States; and described a close relationship between C. nevadensis and C. glabra. but nevertheless separated taxa within the C. arizonica complex. Analyses of wind-pollinated progenies of single trees showed the narrow endemic, C. glabra, to have a greater degree of population differentiation than the more broadly dispersed C. arizonica. In addition, genetic variances within the numerically small populations of C. arizonica were about the same as in the much larger populations of C. glabra. The results also suggested that genetic variability in C. stephensonii, a taxon occurring in a single population, may occur primarily among inbred lines. While the genetic structures of C. arizonica and C. glabra have counterparts among broadly dispersed conifers, that of C. stephensonii appears to be unique. Together, the results support the view that genetic structure primarily reflects the uncertain, chance events that are interspersed throughout evolutionary history. 相似文献
4.
山玉兰花粉离体萌发和花粉管生长特性的研究 总被引:1,自引:0,他引:1
山玉兰(Magnolia delavayi)是木兰科木兰属的常绿乔木或大型灌木,是重要的园林造景、庭院绿化素材,也是重要的育种资源。山玉兰花粉的研究对其杂交育种的成败具有重要影响,但目前尚未见其花粉活力的相关报道。该研究以新鲜的山玉兰花粉为对象,采用悬滴培养法分析了温度、光照以及培养液的蔗糖和硼酸浓度对山玉兰花粉萌发的影响。结果表明:(1)山玉兰花粉萌发时,最适宜的温度为27℃。(2)光暗条件下,山玉兰花粉以浓度为5%的蔗糖培养效果最佳,其萌发率在16%以上;而硼酸浓度则以0.001%的培养效果最佳。(3)蔗糖与硼酸共同作用可有效促进花粉萌发和花粉管生长。其中,在光照条件下,以5.0%蔗糖+0.001%硼酸为最适宜的培养液,花粉萌发率达41.27%,花粉管长达281.49μm;而在黑暗条件下,则以5.0%蔗糖+0.01%硼酸为最适宜的培养液,花粉萌发率达45.71%,花粉管长达254.00μm。该研究结果为进一步开展人工辅助授粉、发掘山玉兰的种质资源工作奠定了基础。 相似文献
5.
温度对四川小金县岷江柏种子发芽的影响 总被引:1,自引:0,他引:1
通过对采自四川小金县的岷江柏(Cupressus chenggiana S. Y. Hu)种子发芽特征的研究,分析不同温度对种子发芽的影响.结果表明,采自四川小金县的岷江柏种子发芽周期为20 d,其中0 ~5 d为萌动期,5 ~15 d为高峰期;发芽温度为5℃~30℃,适宜发芽温度为10℃~25℃,种子最适发芽温度在2003年1、4、7和10月分别为25℃、15℃、20℃和20℃.岷江柏种子的最适发芽温度和贮藏过程中的发芽特征与环境温度有着密切的关系. 相似文献
6.
With regard to adaptation of green ash (Fraxinus pennsylvanica
Marshall) to ecological conditions in Croatia, pollen germination and pollen tube length after 2, 4 and 6 hours were examined in vitro at 10, 15, 20 and 25°C during two years 2001 and 2002. Narrow leaved ash (F. angustifolia
Vahl) pollen served as a control in 2002. The year, time and temperature, and the interaction between time and temperature were
significant for both germination percentage and pollen tube length. Interactions year × temperature and year × time were significant
for pollen tube length only. The highest germination percentage (17.86% in 2001 and 19.40% in 2002) of green ash pollen was
at 15°C after 6 hours. The pollen tube length was greatest at 20°C (393.46 μm) in 2001 and 25°C (899.50 μm) in 2002 after
6 hours. Narrow leaved ash pollen had the highest germination percentage (19.22%) at 20°C after 6 hours and was significantly
reduced at 25°C. The pollen tube length was greatest at 25°C (518.90 μm) after 6 hours. It can be concluded that green ash
pollen has satisfactory germination in ecological conditions in Croatia and that the optimum temperature for pollen germination
is higher than 20°C. 相似文献
7.
长木蜂蜂粮酿制过程中pH值和花粉活力的测定 总被引:2,自引:0,他引:2
测定手采新鲜的芍药花粉、芍药长木蜂Xylocopa tranquebarorum(Swederus)花粉和不同酿制时间蜂粮样品的平均pH值,结果分别是6.19、5.92和4.05(40日龄蜂粮)。随着酿制时间的延长,蜂粮的pH值下降,2日龄蜂粮到3日龄蜂粮的pH值从5.57降至4.82,下降速率明显。经测定,紫藤长木蜂花粉和不同日龄蜂粮样品中紫藤花粉的纯度均在98%以上;芍药长木蜂花粉和不同日龄蜂粮样品中芍药花粉的纯度均在93%以上;测定紫藤花粉的长木蜂蜂粮和芍药花粉的长木蜂蜂粮中的花粉活力。结果表明,在1日龄蜂粮中花粉活力基本丧失,3日龄后均失去萌发力,并且不同的花粉蜂粮其花粉活力表现一致。 相似文献
8.
ABSTRACT Cupressus sempervirens L. var. pyramidalis and C. sempervirens var. horizontalis were examined for their pollen morphometry and ultrastructure to verify whether, in addition to phenotype, pollen could also show characteristics useful to discriminate the two infraspecific taxa. C. sempervirens var. pyramidalis compared to C. sempervirens var. horizontalis has mainly larger, subcircular pollen with a higher percentage of apolar and germinating grains, and a wall with thicker intine; the cytoplasm has a greater number of callose-containing vesicles. C. sempervirens var. horizontalis has pollen distributed in five classes of shape. In addition it is smaller and shows a higher percentage of ruptured grains, and a lower percentage of germination in vitro. The cytoplasm contains vesicles rich in callose and also a higher amount of osmophilic bodies. Pollen grains in both varietas contain only one cell at dispersal. The reported differences in pollen morphometry, structure and biology, together with the phenotypic characteristics of the tree, support the validity of two infraspecific taxa. 相似文献
9.
苏铁属花粉萌发及保存条件研究 总被引:2,自引:0,他引:2
以不同浓度梯度的蔗糖与硼酸组合在不同pH条件下用悬浮培养法测定德保苏铁、叉叶苏铁、元江苏铁和越南篦齿苏铁花粉的活力;将元江苏铁和越南篦齿苏铁花粉分别保存在不同低温、不同湿度的环境中,研究温度和湿度对保存花粉的影响。结果表明:(1)最适合苏铁属植物花粉萌发的培养液配方为蔗糖(1%~2.5%)+硼酸(100~500 mg/L),pH6.0~7.0;(2)在室温下,将苏铁花粉密封保存在有干燥剂的容器中,可存活30 d以上;(3)在0℃条件下,不加干燥剂,花粉可保存4个月以上;(4)用液氮保存后的越南篦齿苏铁花粉进行人工授粉,结实率高达90.3%,与用新鲜花粉人工授粉的结实率无明显差异;(5)将花粉含水率降低到15.5%~13.2%后,能在液氮中进行长期保存,表明花粉液氮保存可以作为苏铁花粉长期和超长期保存的方法。 相似文献
10.
Temperature is a major climatic factor that limits geographical distribution of plant species, and the reproductive phase has proven to be one of the most temperature-vulnerable stages. Here, we have used peach to evaluate the effect of temperature on some processes of the progamic phase, from pollination to the arrival of pollen tubes in the ovary. Within the range of temperatures studied, 20 degrees C in the laboratory and, on average, 5.7 degrees C in the field, the results show an accelerating effect of increasing temperature on pollen germination and pollen tube growth kinetics, as well as an increase in the number of pollen tubes that reach the style base. For the last two parameters, although the range of temperature registered in the field was much lower, the results obtained in the laboratory paralleled those obtained in the field. Increasing temperatures drastically reduced stigmatic receptivity. Reduction was sequential, with stigmas first losing the capacity to sustain pollen tube penetration to the transmitting tissue, then their capacity to offer support for pollen germination and, finally, their capacity to support pollen grain adhesion. Within a species-specific range of temperature, this apparent opposite effect of temperature on the male and female side could provide plants with the plasticity to withstand changing environmental effects, ensuring a good level of fertilization. 相似文献
11.
Effect of smoke derivatives on in vitro pollen germination and pollen tube elongation of species from different plant families
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A. Kumari H. B. Papenfus M. G. Kulkarni M. Pošta J. Van Staden 《Plant biology (Stuttgart, Germany)》2015,17(4):825-830
Plant‐derived smoke stimulates seed germination in numerous plant species. Smoke also has a positive stimulatory effect on pollen germination and pollen tube growth. The range of plant families affected my smoke still needs to be established since the initial study was restricted to only three species from the Amaryllidaceae. The effects of smoke‐water (SW) and the smoke‐derived compounds, karrikinolide (KAR1) and trimethylbutenolide (TMB) on pollen growth characteristics were evaluated in seven different plant families. Smoke‐water (1:1000 and 1:2000 v:v) combined with either Brewbaker and Kwack's (BWK) medium or sucrose and boric acid (SB) medium significantly improved pollen germination and pollen tube growth in Aloe maculata All., Kniphofia uvaria Oken, Lachenalia aloides (L.f.) Engl. var. aloides and Tulbaghia simmleri P. Beauv. Karrikinolide (10?6 and 10?7 m ) treatment significantly improved pollen tube growth in A. maculata, K. uvaria, L. aloides and Nematanthus crassifolius (Schott) Wiehle compared to the controls. BWK or SB medium containing TMB (10?3 m ) produced significantly longer pollen tubes in A. maculata, K. uvaria and N. crassifolius. These results indicate that plant‐derived smoke and the smoke‐isolated compounds may stimulate pollen growth in a wide range of plant species. 相似文献
12.
In vitro germination of wheat pollen on raffinose medium 总被引:1,自引:0,他引:1
13.
Response of in vitro pollen germination and pollen tube growth of groundnut (Arachis hypogaea L.) genotypes to temperature 总被引:3,自引:0,他引:3
V. G. KAKANI P. V. V. PRASAD P. Q. CRAUFURD & T. R. WHEELER 《Plant, cell & environment》2002,25(12):1651-1661
Air temperatures of greater than 35 °C are frequently encountered in groundnut‐growing regions, especially in the semi‐arid tropics. Such extreme temperatures are likely to increase in frequency under future predicted climates. High air temperatures result in failure of peg and pod set due to lower pollen viability. The response of pollen germination and pollen tube growth to temperature was quantified in order to identify differences in pollen tolerance to temperature among 21 groundnut genotypes. Plants were grown from sowing to harvest in a poly‐tunnel under an optimum temperature of 28/22 °C (day/night). Pollen was collected at anther dehiscence and was exposed to temperatures from 10° to 47·5 °C at 2·5 °C intervals. The results showed that a modified bilinear model most accurately described the response to temperature of percentage pollen germination and maximum pollen tube length. Genotypes were found to range from most tolerant to most susceptible based on both pollen characters and membrane thermostability. Mean cardinal temperatures (Tmin, Topt and Tmax) averaged over 21 genotypes were 14·1, 30·1 and 43·0 °C for percentage pollen germination and 14·6, 34·4 and 43·4 °C for maximum pollen tube length. The genotypes 55‐437, ICG 1236, TMV 2 and ICGS 11 can be grouped as tolerant to high temperature and genotypes Kadiri 3, ICGV 92116 and ICGV 92118 as susceptible genotypes, based on the cardinal temperatures. The principal component analysis identified maximum percentage pollen germination and pollen tube length of the genotypes, and Tmax for the two processes as the most important pollen parameters in describing a genotypic tolerance to high temperature. The Tmin and Topt for pollen germination and tube growth, rate of pollen tube growth were less predictive in discriminating genotypes for high temperature tolerance. Genotypic differences in heat tolerance‐based on pollen response were poorly related (R2 = 0·334, P = 0·006) to relative injury as determined by membrane thermostability. 相似文献
14.
Onoriode Coast Alistair J. Murdoch Richard H. Ellis Fiona R. Hay Krishna S.V. Jagadish 《Plant, cell & environment》2016,39(1):26-37
Resilience of rice cropping systems to potential global climate change will partly depend on the temperature tolerance of pollen germination (PG) and tube growth (PTG). Pollen germination of high temperature‐susceptible Oryza glaberrima Steud. (cv. CG14) and Oryza sativa L. ssp. indica (cv. IR64) and high temperature‐tolerant O. sativa ssp. aus (cv. N22), was assessed on a 5.6–45.4 °C temperature gradient system. Mean maximum PG was 85% at 27 °C with 1488 μm PTG at 25 °C. The hypothesis that in each pollen grain, the minimum temperature requirements (Tn) and maximum temperature limits (Tx) for germination operate independently was accepted by comparing multiplicative and subtractive probability models. The maximum temperature limit for PG in 50% of grains (Tx(50)) was the lowest (29.8 °C) in IR64 compared with CG14 (34.3 °C) and N22 (35.6 °C). Standard deviation (sx) of Tx was also low in IR64 (2.3 °C) suggesting that the mechanism of IR64's susceptibility to high temperatures may relate to PG. Optimum germination temperatures and thermal times for 1 mm PTG were not linked to tolerating high temperatures at anthesis. However, the parameters Tx(50) and sx in the germination model define new pragmatic criteria for successful and resilient PG, preferable to the more traditional cardinal (maximum and minimum) temperatures. 相似文献
15.
N. P. Matveeva E. A. Lazareva T. P. Klyushnik S. A. Zozulya I. P. Ermakov 《Russian Journal of Plant Physiology》2007,54(5):619-625
Proteins diffusing from tobacco pollen grains into external medium, being inactivated by low temperature (0°C), were shown to stimulate pollen germination in vitro. Fractionation of these proteins by affinity chromatography using α-D-methylmannopyranoside (MMP) immobilized on agarose resulted in the isolation of lectins stimulating germination. The mol wts of these lectins were estimated by SDS-PAGE as 58, 69, and 74 kD. A stimulatory effect of these lectins was determined by their specific interaction with carbohydrate determinants because a competitive sugar (0.3 M MMP) suppressed completely lectin effect on germination. Polyvalent lectins capable of erythrocyte agglutination were also found among diffused proteins. These lectins are glycoproteins with Glu/Man carbohydrate determinants. MMP did not affect their capability of agglutination. This finding permits a conclusion that pollen grain wall contains lectins differing in their carbohydrate specificity. 相似文献
16.
Flavonol-deficient petunia pollen [conditionally male fertile (CMF) pollen] is unable to germinate but application of nanomolar
concentrations of flavonol aglycones completely restores function (Mo et al. 1992). In this study a chemically synthesized
radioactive flavonol, [4′-O-14C]kaempferide, was used as a model compound to study the metabolism of flavonols during the first few hours of pollen germination.
[4′-O-14C] Kaempferide was as efficient at inducing CMF pollen germination as kaempferol and quercetin, the aglycone form of the endogenous
flavonols in petunia pollen. Analysis by high-performance liquid chromatography (HPLC) of extracts from both in-vitro-germinated
pollen and the germination medium showed that more than 95% of the applied radioactivity was recovered as three kaempferide
3-O-glycosides and unmetabolized kaempferide; no flavonol catabolites were detected. Only HPLC fractions that contained the aglycone, or produced
it upon acid hydrolysis, could induce CMF pollen germination in vitro. Structurally diverse flavonols could be classified
according to how efficiently the aglycone was internalized and glycosylated during pollen germination. The ability of an individual
flavonol to restore germination correlated with the total uptake of flavonols but not with the amount of glycoside formed
in the pollen. Thus this study reinforces the conclusion that flavonol aglycones are the active compound for inducing pollen
germination.
Received: 4 November 1996/Accepted: 4 December 1996 相似文献
17.
In this study, pollens of Burdur dimriti, Sariemin, Tilki kuyrugu, Razaki, Buzgulu, Siyah buzgulu, and Siyah gemre table grape
varieties (Vitis vinifera L.) grown in Isparta, Turkey were tested in vitro for viability, germination capability, and production level. It was determined that active pollen levels varied between 23.8
% and 80.8 % in FDA (flourescein diacetat), 31.5 % and 68.8 % in TTC (2,3,5-triphenyl tetrazolium chloride) tests. In respect
to pollen germination rates, the best medium in hanging drop method and saturated petri method were 20 % sucrose concentration
and 1 % agar+15 % sucrose solution, respectively. The highest and the lowest pollen production levels per flower were determined
9000 in Siyah gemre and 2906 in Siyah dimrit grape varieties, respectively. 相似文献
18.
Freshly released pollen of black elderberry (Sambucus nigra L.) was incubated under various culture conditions until germination was achieved. Optimal conditions for germination were determined and used for maturation of unicellular microspores in vitro. Staining with 5-diphenyltetrazolium bromide, propidium iodide and iodine potassium iodide was used to assess pollen viability, nuclear phase and maturation, respectively. The germination rate was highest when fresh pollen was agitated at 40 rpm in Petri dishes containing a liquid medium consisting of Brewbaker and Kwack salts, 15% (w/v) sucrose, 500 mg/l MES sodium salt, at pH 5.0; germination reached nearly 70% after only 1 h in culture. Under these conditions, and with addition of 200 mg/l glutamine, 260 mg/l cytidine and 500 mg/l uridine, uninucleate microspores developed into mature pollen at a 12% germination rate. Our report is the first demonstration of maturation of S. nigra microspores in vitro. 相似文献
19.
Arabidopsis ACT11 modifies actin turnover to promote pollen germination and maintain the normal rate of tube growth
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Actin is an ancient conserved protein that is encoded by multiple isovariants in multicellular organisms. There are eight functional actin genes in the Arabidopsis genome, and the precise function and mechanism of action of each isovariant remain poorly understood. Here, we report the characterization of ACT11, a reproductive actin isovariant. Our studies reveal that loss of function of ACT11 causes a delay in pollen germination, but enhances pollen tube growth. Cytological analysis revealed that the amount of filamentous actin decreased, and the rate of actin turnover increased in act11 pollen. Convergence of actin filaments upon the germination aperture was impaired in act11 pollen, consistent with the observed delay of germination. Reduction of actin dynamics with jasplakinolide suppressed the germination and tube growth phenotypes in act11 pollen, suggesting that the underlying mechanisms involve an increase in actin dynamics. Thus, we demonstrate that ACT11 is required to maintain the rate of actin turnover in order to promote pollen germination and maintain the normal rate of pollen tube growth. 相似文献