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1.
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
2.
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
3.
Summary Eleven populations of Brassica napus L. and twelve populations of B. campestris L. were subjected to three cycles of selection for fast germination at 2°C and at 25°C. The seeds from the selected populations, and unselected control populations grown in the same environment as the selected populations, were examined for germination behaviour at 2°C and 25°C, and for growth behaviour at 10°C. The populations in both species responded differently in terms of germination behaviour to selection for fast germination. In most of the populations that did respond positively to selection, selection practised at 2°C was superior to selection at 25°C in improving percent germination at 2°C, and was as good as the selection at 25°C in improving germination rate at the higher temperature. Selection for fast germination had no effect on growth characteristics of B. napus and B. campestris populations grown at 10°C. Thus, selection for fast germination at one low temperature may lead to improvement in germination characteristics over a range of temperatures, but will not necessarily lead to improved growth performance of the selected populations. 相似文献
4.
Summary In vitro pollen germination at 10°C, 14°C and 22°C of four groups of two pure line tomato varieties was compared with their plant growth at 19°C D/10°C N under controlled environmental conditions. Generally, pollen germination was slow at 10°C but after 6 h the percentage of germination was similar to that at 22°C. Maximum germination was obtained at 14°C already after 4 h. The longest pollen tubes occurred at 22°C. The two varieties within each group differed significantly from each other for percentage of pollen germination. For one group, this difference was greater at 10°C than at 22°C. The varieties in two groups also differed significantly for pollen tube growth. These differences in pollen tube growth rate were greater at 22°C than at 10°C. There was no clear relationship between pollen germination, pollen tube growth and plant growth in any of the four pairs of varieties. The results are discussed with regard to the possibility of pollen selection at low temperature in order to improve the efficiency of breeding for growth at low temperature. 相似文献
5.
Q. B. Zielinski 《Euphytica》1968,17(1):121-125
Summary Temperature and humidity immediately before dehiscence were important in maintaining viability and germination of filbert pollen. Air temperatures at or above 23°C during dehiscence and pollen storage resulted in nonviability after 8–24 h. Cut branches bearing elongating catkins when exposed to temperatures of 18°±2°C during dehiscence yielded viable pollen. Manganese and boron added to the medium did not significantly increase germination, while 10–100 p.p.m. boron appeared to inhibit it. Storage tests indicated that filbert pollen viability may be maintained at 92% relative humidity and –18°C for at least 12 months.Also published as Tech. Paper No. 2305, Oregon Agricultural Experiment Station. 相似文献
6.
花期高温胁迫对水稻花药生理特性及花粉性状的影响 总被引：6，自引：0，他引：6
为探明花期高温胁迫对水稻花器官的影响机制,以耐热水稻品系996和热敏感水稻品系4628为材料,在人工气候室进行高温(8:00~17:00,37℃;17:00~次日8:00,30℃)和适温处理(8:00~17:00, 30℃;17:00~次日8:00,25℃), 研究高温胁迫对水稻花药抗氧化酶活性、膜透性、MDA含量及花粉性状等生理特性的影响。结果表明,高温胁迫下,水稻花药中SOD、POD、CAT、AsA-POD活性在高温胁迫初期均明显增加,尔后快速下降,耐热品系996这四种酶活性增幅大于热敏感品系4628;热敏感品系4628花药中MDA含量和膜透性在高温胁迫下增幅大于耐热性品系996;高温胁迫导致花药开裂、花粉萌发率和柱头上花粉粒数的显著下降,花粉粒直径增大。但耐热品系996的前3项参数显著高于热敏感品系4628。高温胁迫下水稻花药中保持较高抗氧化酶活性、较好的花粉散落特性和花粉萌发特性及较低的膜透性和MDA含量,是品种耐高温的生理基础。 相似文献
7.
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
8.
Haploid selection for traits related to pollen cold tolerance in tomato was performed in segregating populations derived from a Lycopersicon esculentum × L. pennellii hybrid. BC1 populations were obtained by combining normal and low temperature treatments on two stages of pollen development: pollen formation, and germination and pollen tube growth. F1 hybrids were cultivated under low and normal temperatures and their pollen was used to pollinate L. esculentum plants at low and normal temperatures. The four BC1 populations obtained were tested for the quality and quantity of pollen produced at low temperatures. The population obtained by cold treatment at both stages had a significantly improved pollen germination ability at low temperatures. The two other coldselected BC1 populations showed no differences compared with the unselected BC population. A second cycle of pollen selection, corresponding to BC2, was applied in order to test its persistence in the subsequent generations and the possibility to further improve the character. This second cycle showed no improvement although some plants retained the high pollen germination ability at low temperatures that was observed in the first cycle. Hence, gametophytic selection of some characters related with tomato pollen performance may be feasible, at least for the first cycle of selection. 相似文献
9.
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
10.
Low temperature storage of pistachio pollen 总被引：3，自引：0，他引：3
Summary Pollen from four male pistachio (Pistacia vera L.) clones was stored at –196°C and –20°C for up to 12 months and tested for ability to germinate in vitro following a period of hydration at high humidity. Germination of fresh pollen was high (>80%) for each clone. At –196°C, pollen of cv. Peters survived freezing, storage and thawing with no loss of germinability; pollen of the other three clones had sharp declines in germination possibly attributable to cellular lesions incurred during freezing or thawing. When the relative humidity of the –20°C storage environment was maintained at or near 33%, Peters pollen had high rate of germination through 12 months storage. Without control of relative humidity, Peters pollen germination was high at 4 months, but declined at 12 months. Germination requirements became more exacting for pollen stored at –20°C for 12 months at suboptimal humidity conditions. Pollen of the other three clones did not tolerate storage at –20°C as well as Peters pollen regardless of the storage humidity environment. 相似文献
11.
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
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.
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
14.
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
15.
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
16.
Ingileif S. Kristjansdottir 《Euphytica》1991,58(1):71-80
Summary The temperature-related performances of six tetraploid potato clones, two Andean, three European, and one hybrid, were compared by cultivating them in growth chambers under one of two temperature regimes: 10°C day/4°C night or 20°C day/10°C night. Preformance was measured in terms of biomass production and pollen germinability.For dry matter yield at second harvest, the temperature-related performance ratios (performance at 10°C/4°C divided by performance at 20°/10°C) were highest for the Andean clones, intermediate for the Andean/European hybrid clone 2015×S12, and lowest for the European cultivars. The ability of the European cultivars to maintain their normal rates (i.e. rates at 20/10°C) of biomass production when cultivated at low temperatures varied greatly, with clone S3 performing most poorly at 10/4°C.For pollen germinability in vitro, performance ratios were highest for the hybrid clone 2015×S12 and lowest for the European clones.The high tuber yield of hybrid 2015×S12 at 10/4°C can be attributed to its low-temperature tolerance and it being daylength neutral. 相似文献
17.
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
18.
R. A. Whitehead 《Euphytica》1963,12(2):167-177
Results of experiments on collection, viability testing, storage and dispatch of coconut pollen are given, and their relevance to the breeding of coconuts is briefly discussed.Pollen was obtained in large quantities following oven-drying of male flowers at 40° C. Viability decreased as drying time increased but viable grains were obtained in greater numbers after two days than after drying for a single day.Germination of pollen in vitro was better at 30° C and 35° C than at other temperatures tried; media with high gelatine concentrations (30%) seemed superior to those with less gelatine.For normal breeding purposes storage of pollen for two or three months is adequate. At low temperature, reliable storage in sealed ampoules for at least this period was obtained after further drying pollen over silica gel. Some samples retained good viability for considerably longer. Most samples stored over silica gel were still viable after 5 months, though viability was low. Over damp CaCl2 considerable reduction in viability occurred during the first month but there was little further reduction at least up to 7 months after collection, and all samples were still viable after 18 months. Freeze-dried pollen in ampoules under vacuum had up to 40% viability after storage for one year.At room temperature, viability of pollen kept at controlled humidities over sulphuric acid solutions, though retained for longer periods than in an uncontrolled atmosphere, was only reliably maintained for about three weeks; some samples remained viable for longer periods. Freeze-drying was found to greatly increase the longevity of pollen kept at room temperature; freeze-dried pollen used in a trial shipment to New Guinea retained viability for four months and was successfully used in a number of controlled pollinations. 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.
Summary An investigation into the conditions that lead to higher seed yields from species crosses of tulip has revealed that the temperature has an effect on seed production. Under constant temperatures, the best results in the phytotron were obtained at 14 °C.Various problems associated with such crosses have been explained on the basis of microscopical observations. One of the factors associated with a poor seed yield from interspecific tulip crosses is the abnormal growth of the pollen tubes in the embryo-sac cavities of numerous ovules, with the result that fertilization does not take place.The failure of the cross between Red Pitt, a Darwin tulip of the species T. gesneriana and the T. fosteriana tulips Mad. Lefeber and Princeps appears to be due to an inhibition of the pollen tube growth in the stigma. 相似文献