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1.
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
2.
Summary Pollen grains from selected cutivars of almond [Prunus dulcis (Mill.) D. A. Webb] and peach (Prunus persica
Batsch L.) were exposed to a range of temperatures between 1°C and 34°C on a thermogradient plate. Pollen germination at temperatures below 9°C was conspicuously greater in almond than peach. Miximal germination percentages were attained at about 16°C (almond) and 23°C (peach). The two species did not differ in their capacity for pollen tube elongation over a broad range of temperatures. Maximal pollen tube elongation occurred at temperatures 5°C to 8°C higher than maximal pollen germination. Species affiliation appeared to be of much greater consequence than chilling requirement or bloom date of the sporophyte in predicting gametophytic response to temperature. 相似文献
3.
A. H. Eenink 《Euphytica》1981,30(1):71-76
Summary For the production of inbred lines and F1 hybrids in witloof-chicory information is wanted on characteristics such as the incompatibility system. These characteristics can only be studied properly if the influence of temperature and physiological status of the plant on pollen germination and seed production is known. Investigations were carried out with 9 self-incompatible (SI) and 6 self-compatible (SC) clones in glasshouses of the IVT phytotron at constant temperatures of 10, 14, 17, 20, 23 and 26°C. In general, in vivo pollen germination percentages were rather low after self pollination with an optimum for germination around 17–20°C. No seeds were formed at the lowest temperature (10°C) while seed production for SC clones was usually (rather) good at higher temperatures. At 26°C seed production in some clones decreased. Both pollen germination and seed production decreased at the end of the flowering period. There was a rather positive relationship at e.g. 17 and 20°C between pollen germination after selfing and seed production. When no pollen germination was observed, no seed formation occurred. When pollen grains did germinate, seed development would not necessarily occur in all cases. So this relationship only enables negative mass selection for SC. 相似文献
4.
Summary Germination and storage trials were carried out with pollen of several rose varieties. The pollen grains germinated well in a 15% sucrose solution with 40 ppm boric acid. Staining the pollen with a 0.1% tetrazolium solution and standardizing the degree of colour at which the pollen grains are counted as viable, provided a good viability estimate, simpler to carry out than in vitro germination. Germination capacity and staining ability of the pollen were greatly impeded-about halved-by dehydration during storage in desiccators at low humidity. This effect could be corrected by humidifying the pollen beforehand for about one hour, though this pre-treatment increased the percentage of germinated pollen grains more than the percentage stained. There was no difference between the two percentages in fresh or in deep-frozen pollen.Pollen stored at 1°C and high relative humidity soon lost its germination capacity: between 0 and 20% humidity a considerable proportion of the pollen remained viable for 9 months and longer. Storage for the same period in vacuum-sealed glass tubes at –24°C maintained viability as well or better and would probably prolong it further. Some of the cold-stored pollen induced a reasonable seed set after one year, a low seed set was obtained even after two years of storage at 1°C and low humidity. 相似文献
5.
Summary A quantitative examination of pollen grain germination and pollen tube growth within the overy wall was made in selected wheat × tetraploid H. bulbosum hybridizations, to investigate the effect of the wheat and the H. bulbosum genotype on these characters. As expected, variation at the known crossability loci had no effect on pollen grain germination. The frequency of pollen tube penetration of the ovary wall was, however, severely reduced when the dominant alleles were present. Pollen tube penetration was nevertheless observed in 3 of the 110 ovaries examined of the non-crossable cultivar Highbury. The H. bulbosum genotype had a much smaller effect on these characters, but significant differences between the clones were observed in the numbers of pollen tubes initially penetrating the ovary wall. Although two H. bulbosum genotypes showed no significant differences in the number of ovaries with pollen tubes at the base of the ovule, significant differences in the frequency of fertilization were observed. The possible cause of this discrepancy is discussed.The frequency of fertilization in crossable wheat × H. bulbosum hybridizations was improved by the application of gibberellic acid within 10 minutes of pollination, and reduced by an increase in the ambient temperature from 20°C to 26°C. Fertilization following the pollination of non-crossable wheat genotypes was not affected by either of these factors. 相似文献
6.
Summary F2 and BC1 progenies from crosses between tomato (Lycopersicon esculentum) varieties differing for growth capacity at low temperature were produced under controlled conditions by hand pollination under two temperature regimes (22°C D/15°C N, normal temperature (N), and 15°C D/8°C N, low temperature (L)) with pollen formed under both regimes, resulting in four pollination treatments: NN, NL, LN and LL. Vegetative growth of the offspring was compared under a rather low temperature regime (19°C D/10°C N). Populations from different treatments within the progeny of a particular F1 often differed significantly for average dry weight of 7 weeks old plants, the average of the NN population always being higher. Variances for dry weight were sometimes larger for LN populations, but this never resulted from a larger number of vigorous plants. Differences between populations within each progeny seemed to result in part from differences in the conditions for embryo development. Pollen selection at low temperature did not appear to be efficient for sporophyte breeding in this experiment. 相似文献
7.
Storage of avocado pollen 总被引：4，自引：0，他引：4
Margaret Sedgley 《Euphytica》1981,30(3):595-599
Summary Avocado pollen was stored at a range of temperatures and relative humidities (RH) for up to one year and the pollen was tested for viability in vivo.Pollen stored for one month was capable of germination on the stigma and penetrating the ovule when stored at 4°C with <1,23,55 and 75% r.h. and at -196°C with 0% r.h. Most pollen samples stored at 25 and -15°C at a range of r.h. would germinate on the stigma but none would penetrate the ovule.After one year of storage, pollen at 4°C and <1 and 23% r.h. would germinate on the stigma but would not penetrate the ovule. There was no germination of pollen stored at 4°C and 55 and 75% r.h. Only pollen stored at -196°C and 0% r.h. would penetrate the ovule, but thawing and refreezing once during the year destroyed the viability. 相似文献
8.
Summary The effect of temperature on fruit set, seed set and seed germination was studied in Sonia × Hadley Hybrid Tea-rose crosses. Sonia mother bushes were grown at constant temperatures (10, 14, 18, 22, 26°C) in the greenhouses of the phytotron until fruit ripening. Fruit set, fruit weight and number of seeds increased as temperature was higher. Optimum temperatures were found for days to fruit ripening (18°C), seed germination (22°C) and number of seedlings per pollinated flower (22°C). Fruit weight and number of seeds were positively correlated. For crossing and the subsequent growing of seed-bearing plants 22°C was the most favourable temperature. Effects of temperature on pollen tube growth, fertilization and seed germination are discussed. 相似文献
9.
研究了不同浓度的蔗糖和硼酸,在不同温度和培养时间内对阔叶杨桐花粉萌发率和花粉管生长的影响,以期为阔叶杨桐的繁殖育种研究提供依据.结果表明:1)不同浓度的蔗糖和硼酸处理组之间存在显著性差异,蔗糖和硼酸都能促进杨桐花粉萌发和花粉管的生长,但超过一定浓度则会起到抑制作用;2)随着培养温度的升高,花粉萌发率和花粉管长度呈先升后降的趋势;3)随着培养时间的延长,花粉萌发率和花粉管长度逐渐增加,但最初的前12h内花粉萌发快,在培养的前9h内花粉管生长较快.4)实验显示:阔叶杨桐花粉培养的最适培养基是15％蔗糖和0.02％硼酸,最适培养温度为25℃,培养24 h后花粉萌发率为84.32％,花粉管长达2 003.51 μm. 相似文献
10.
A. Dale 《Euphytica》1977,26(3):745-748
Summary Raspberry pollen was stored at 5°C and –13°C for six months and then tested for its ability to induce pyrene set and the production of viable seedlings, and for its effect upon the segregation of a major gene s. Only pollen stored at –13°C gave a pyrene set and germination percentage adequate to produce sufficient seedlings for a breeding programme. It is suggested that tests of pollen viability in the raspberry should include studies of pollen germination, and the effect of this pollen on pyrene set and seed germination. Possible causes of the loss of viability in the pollen stored at 5°C are discussed. 相似文献
11.
The high sterility of tetraploid melon (Cucumis melo L.) plants is a serious inconvenient to obtain economically useful polyploid
lines. In order to study the alterations on diploid pollen tube growth and their influence on sterility, in vitro and in vivo
pollen tube growth from three commercial varieties and its tetraploids was observed. Polyploid pollen grains show a lower
germination percentage in vitro and a slower germination rate than haploid pollen. Furthermore, diploid pollen grains producing
two or three tubes and tube branchings were observed on diploid pollen; this seems to indicate a decrease in its functionality.
In vivo and in vitro pollen behaviours are quite similar, but an interaction between the pollen and the pistillar tissues
was detected in vivo. In the diploid × tetraploid cross, where fruits were not obtained, pollen tubes showed a slow growth
rate at the base of the pistil. The possible effects of these alterations in sterility are discussed in terms of the factors
that could affect fecundation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Effects of high temperatures on mature pollen grains in wild and cultivated maize accessions 总被引：1，自引：0，他引：1
Summary The effects of high temperature on mature pollen of various maize lines were investigated. Genotypic differences in pollen reaction to high temperature were revealed. Pollen grains resistant to high temperature (35°C, 26°C) were characterized by higher germination capacity and better ability to develop normal pollen tubes. The studies are of interest to evaluate reproductive system tolerance and conduct gamete selection at the mature pollen grain stage in maize. 相似文献
13.
S. A. Bowes 《Euphytica》1990,48(3):275-278
Summary Three methods for the long-term storage of narcissus pollen were compared; anthers in glass vials held in a desiccator with calcium chloride at 2°C, and polypropylene straws containing either anthers or naked pollen immersed in liquid nitrogen. Pollen from all storage treatments showed 15–16% germination in vitro after 3 days, compared with 27.4% for fresh pollen. Seed set per pod using pollen stored for 3 days was comparable to that of fresh pollen. However, after 351 days, pollen from anthers at 2°C exhibited only 0.1% germination and failed to set seed whereas no further change in germination rate was recorded for pollen from the two liquid nitrogen treatments and seed set was still equivalent to fresh pollen. 相似文献
14.
Pollen of garden varieties and species of Delphinium that was cryopreserved at –30 °C after 3 hours of air drying and storage on silica gel, had high germination and pollen tube growth in vitroeven after 180-day storage. On the other hand, pollen stored at 25 °C showed a marked decrease in the germination rate within 10 days. The best in vitro germination of Delphinium pollen was on a 1% water agar containing 15% sucrose and 0.005 to 0.01% boric acid and at 15 to 20 °C. Field pollination with the cryopreserved pollen showed higher fruit and seed set than pollination with pollen stored at
25 °C, and was not significantly different from fresh pollen.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Summary Rice varieties were screened for chilling tolerance during germination and vegetative growth using different techniques. The effects of temperature during germination were investigated from 10 to 25°C. The screening was most effective at 10°C. Time of data collection has to be considered in order to discriminate slow germinating from chilling sensitive varieties. Chilling survival tests (10°C) applied at the 2-leaf stage revealed that different chilling durations brought complementary results: the longer treatments allowed to identify the most tolerant varieties, while shorter treatments allowed to distinguish intermediate from most sensitive rices. Results of chilling tests applied at the 2- and the 8-leaf stages showed a high correlation. Low-temperature electrolyte leakage and low-temperature fluorescence were also highly correlated to each other and to survival tests applied at the same development stage. By contrast, weak correlations were observed between low-temperature germination and plantlet chilling survival. It is concluded that low-temperature electrolyte leakage and low-temperature fluorescence are good indicators of chilling tolerance during the vegetative growth. The possibility to use a chilling screening procedure applied at this stage in order to predict the chilling tolerance at other development stages is discussed. 相似文献
16.
Summary Various aspects of pollen longevity, in vitro germination of pollen and controlled pollination in Coffea arabica were investigated. High pollen viability could be maintained for more than two years, much longer than previously reported, by storing it under vacuum at 18°C. The most satisfactory method of in vitro germination of pollen was the hanging drop in a Van Tieghem cell, with a 10°, sucrose solution. For artificial cross-pollination it is necessary to carry out emasculation and bagging at the latest one day before anthesis. The stigmas of unpollinated flowers remained receptive for at least nine days.This paper is published with permission of the Director, Coffee Research Station, Ruiru, Kenya 相似文献
17.
研究温度对白魔芋散粉、花粉萌发、活力保持及自交结实的影响,以离体萌发法测定花粉萌发率,以培养箱法测定恒温自交结实率,以野外套袋法测定自然自交结实率。结果显示:最佳散粉温度22~26℃,18℃低温下可正常散粉,而34~38℃高温下80%以上花株花粉囊无法正常开裂;高浓度钙可加快花粉管的生长;花粉在18、22、26、30、34、38℃下的萌发率分别为8.78%、33.17%、54.90%、38.83%、29.10%、6.98%;花粉在38、34、30、26、22、18℃贮藏下分别在4、4、12、12、25、55 h内丧失活性。恒温培养中仅26℃下有4.35%的自交存活率,野外套袋中日平均温度为23.7℃时有2.94%的自交存活率。白魔芋的散粉培养及离体萌发最佳温度为26℃,温度过高或过低均影响授粉结实率。及时采集花粉、控制温度、调节湿度、适当灌溉均能提高授粉结实率。 相似文献
18.
植物生长调节剂对‘秦冠’苹果花粉管生长和花粉萌发的影响 总被引：1，自引：0，他引：1
研究吲哚乙酸、萘乙酸、赤霉素、2,4-D、6-BA5种植物生长调节剂对苹果花粉管生长和花粉萌发的影响。以贮藏6个月的‘秦冠’花粉为材料,配制不同浓度梯度植物生长调节剂的固体培养基培养花粉,研究不同浓度植物激素对花粉管生长和花粉萌发的影响。结果表明,当吲哚乙酸≤1 mg/L、萘乙酸≤1 mg/L、6-BA≤5 mg/L、赤霉素≤10 mg/L时对花粉萌发有轻微促进作用,当浓度增大时抑制作用较突出;2,4-D对花粉萌发存在明显抑制作用;当赤霉素、2,4-D、吲哚乙酸、萘乙酸、6-BA浓度分别达到50、30、30、15、25 mg/L时,花粉遭受浓度迫害出现畸形扭曲。吲哚乙酸、萘乙酸、赤霉素、2,4-D、6-BA对‘秦冠’花粉管生长和花粉萌发均无明显促进作用,并且随浓度增大抑制作用较明显,人工辅助授粉时用于添加剂效果不理想。 相似文献
19.
Storage of sugarbeet pollen 总被引：1，自引：0，他引：1
Summary To develop the technology for long-term pollen preservation, sugarbeet pollen was collected from plants grown in the greenhouse and in the field, and was stored 1 day to 1 year at 5, -18, and -196°C. Pollen containing about 12% moisture was successfully stored in liquid nitrogen (LN2) up to 1 year; this pollen effected fertilization of male-sterile flowers as well as freshly collected pollen. Germination of the resultant seed was good and not different from seed from fresh pollinations. Pollen stored at -18°C for 1 year did not result in as much seed set as fresh pollen, and 1 year at 5°C was essentially lethal. In vitro pollen germination served as a post-storage viability measure, provided the pollen was hydrated before germination. The methods tested in these experiments provided a relatively simple, reliable, and inexpensive means for preservation of sugarbeet pollen for breeding purposes and for preservation of genetic resources.Joint contribution of the Agricultural Research Service, USDA, and the Beet Sugar Development Foundation. 相似文献
20.
The effects of high-temperature stress on the germination of pollen grains of upland cotton during square development 总被引：1，自引：0，他引：1
The reproductive stage of flowering plants is sensitive to high-temperature stresses. High temperature is a major factor influencing pollen grain viability in upland cotton (Gossypium hirsutum). The objective of this study was to identify the relationship between cotton pollen germination percentage and temperature by assaying the pollen germination of four upland cotton cultivars in vitro at different temperatures during the blooming period. The results showed that in vitro pollen germination percentage was related to the culture temperature of pollen germination and the temperature of the square development process. High temperature affected pollen development and germination, and high-temperature tolerance differed among the cotton cultivars. The pollen germination percentage decreased rapidly with changes in the culture temperature from 30 to 39 °C. A culture temperature of 35 °C might be a critical temperature for the pollen viability transition and could be used to screen cotton cultivars that have pollen grains with high-temperature resistance. Before the high-temperature stage, cultivars with rates of decrease in the percentage of pollen germination of less than 41 % at 35 °C relative to the rates at 30 °C might be considered as high-temperature tolerance cultivars, and cultivars with rates of decrease in the percentage of pollen germination greater than 41 % might be considered as susceptible cultivars. The high-temperature stress for pollen grain germination in vitro was greater than 30 °C, and the high-temperature stress for square development might be greater than 33 °C. Boll retention was significant; it was positively correlated with the pollen germination percentage and negatively correlated with temperature during the high-temperature stage. This study provided a method for rapidly screening cultivars (lines) with high-temperature tolerance pollen in upland cotton breeding. 相似文献