首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 728 毫秒
1.
Summary With in vitro culture of ovules, interspecific hybrids have been obtained in an otherwise incompatible cross between a diploid (Gossypium arboreum) and a tetraploid (G. hirsutum) cultivated cotton. The early abortion of the embryo was prevented by repeated treatment of the flowers, immediately after pollination with a solution of gibberellic acid and naphthalene acetic acid. The ovules excised three days after pollination and cultured in a liquid medium underwent profuse proliferation, whereas on an agar-solidified medium supplemented with casein hydrolysate, indoleacetic acid and kinetin they germinated to form hybrid plants.  相似文献   

2.
Summary Interspecific hybrids were generated from crosses between 4 Zinnia angustifolia clones (maternal parents) and an inbred line of Z. elegans Orange King (paternal parent) to investigate the influence of Z. angustifolia genotype on morphology and flowering of hybrids. Leaf length, leaf width, flower diameter, number of ray petals, and days to flowering of interspecific hybrids were significantly influenced by Z. angustifolia clonal genotype. Genetic analysis of hybrid morphology and development was performed using 2 parental Z. angustifolia clones and 18 F1 (9 seedlings from each of 2 populations generated from reciprocal crosses between parental clones) as maternal parents in crosses with Z. elegans Orange King. Genotype of Z. angustifolia significantly affected plant height, fresh weight, number of nodes, and days to flowering of interspecific hybrids. Control of these traits was through the Z. angustifolia nuclear genome. Improvement in interspecific hybrid morphology or development, i.e., shorter stature, earlier flowering, or larger flowers, may be possible by selection of superior-performing Z. angustifolia clones as parents.  相似文献   

3.
Summary Pollen germination and pollen tube growth after self- and intra- and interspecific pollinations of annual [M. scutellata (L.) Mill., M. disciformis DC., and M. rigidula (L.) All.] and perennial (M. sativa L.) Medicago species were studied using a Carl Zeiss microscope with a fluorescence filter attachment.Self-pollination of self-fertile annual and intraspecific pollination of cross-fertile perennials were characterized by high pollen germination and rapid normal pollen tube growth. In contrast pollen germination percentages were very low and many pollen tube growth abnormalities occurred following interspecific pollination and self-pollination of self-sterile plants. The time period from pollination to fertilization for interspecific crosses was about double that following self-pollination of the annual species. However, fertilization occurred frequently following interspecific pollinations. Much of the sterility was due to factor(s) operating after fertilization.Cooperative investigations of the Kansas Agricultural Experiment Station, Dept. of Agronomy and the U.S. Department of Agriculture, Agricultural Research Service. Contribution No. 82-582-J- Mention of a trademark name or proprietary product does not constitute a guarantee or warranty by the U.S. Department of Agriculture, and does not imply its approval over other products that also may be suitable.  相似文献   

4.
Summary Pollen of 4 Cucumis sativus genotypes and of the related species C. metuliferus and C. zeyheri 2x was irradiated with four doses of -rays: 1, 2, 4 and 5 kGy. Higher radiation doses were found to inhibit germination and pollen tube growth in vitro with C. sativus, the most sensitive species.Irradiated pollen of cucumber never performed normal fertilization. However, after radiation with 1 kGy, cucumber pollen was able to occupy all available ovules, of which about 50% developed into empty seeds without embryo. This makes 1 kGy-irradiated maternal pollen less suitable to serve as mentor pollen in interspecific hybridizations. Doses of 2 kGy and more appeared to eliminate the ability to compete for ovules, while fruit set after a 2 kGy radiation was still high.  相似文献   

5.
Summary A genetic resources preservation program led to an in vitro germplasm collection of yam (Dioscorea spp.), obtained by nodal cutting and maintained under slow growth conditions with ((Knop, 1865) in George & Sherrington, 1984) modified medium. The collection comprises accessions of 14 species from Africa and Asia, including edible varieties from the humid intertropical areas, viz 10 wild species (D. abyssinica, D. bulbifera, D. burkilliana, D. dumetorum, D. hirtiflora, D. mangenotiana, D. minutiflora, D. praehensilis, D. schimperana, D. togoensis), 5 edible species (D. alata, D. bulbifera, D. cayenensis-D. rotundata complex, D. dumetorum and D. esculenta) and 1 interspecific hybrid (D. cayenensis-D. rotundata complex, cv. Krengle x D. praehensilis). Three factors that may influence the success in transfer from the in vivo to the in vitro conditions have been studied. These are: the type of introducted material (nodal cutting fragments, seeds and exchanged microplants), the introduction date and the genotype. Some significant differences in success were due to the type of introduced material, whereas the introduction date had no effect. On the other hand, some species showed a greater success in the transfer from the in vivo to the in vitro conditions than others. The three tuberization types (basal tuberization, aerial tuberization and boulage (tuberization without vegetative development) phenomena), according to species, are discussed.  相似文献   

6.
Summary Immature embryos of Glycine max (L.) Merr. cv. Bay, G. tabacina (Labill.) Benth. and G. tomentella Hayata were cultured on 72 media combinations to identify a nutrient medium which would allow a greater percentage of interspecific plants to be recovered from cultured embryos of G. max × various perennial Glycine species. The highest mean plant recovery rate of 79% was from a medium containing B5 nutrient salts as reported by Gamborg et al. (1968), vitamin components according to Williams (1978) and 30 g/l sucrose. This is as compared with 25% from a medium used previously. In an additional test, 67% of hybrid embryos of G. max × G. tomentella were recovered from the same medium, from which G. tomentella was most effectively recovered in all testing.Contribution No. 89-276-J of the Kansas Agric. Exp. Stn., Manhattan.  相似文献   

7.
Summary The pre-and post-fertilization barriers in the interspecific crosses between Vigna umbellata and V. minima were investigated. In the reciprocal crosses (V. minima as the parent) the entry of pollen tubes into the ovary was delayed by about 4 h, and no seed set was observed. However, no pre-fertilization barriers were encountered in crosses involving V. minima as the parent and V. umbellata as the parent (normal cross). The delay/absence of divisions in the endosperm and the failure of embryo to divide were the post-fertilization barriers responsible for somatoplastic sterility in normal crosses which yielded a few hybrid seeds. The hybrid seeds showed poor germinability. The F1 hybrids were intermediate between the parents in most morphological characters, and are completely sterile for pollen. Backcrossing of F1 hybrid with both the parents did not restore fertility in the progenies. V. minima is considered as the tertiary gene pool of the rice bean.  相似文献   

8.
Tsutomu Yabuya 《Euphytica》1991,52(3):215-219
Summary Following bud pollination of tartary buckwheat (Fagopyrum tataricum) with pollens from common buckwheat (F. esculentum), cv. Mancan, 31% of the ovaries began to grow but all turned brown and withered after 6 to 14 days. Fluorescence microscopy of the growing ovaries showed the pollen-tube entering the embryo-sac. The ovules from the growing ovaries failed to produce any embryo in the culture medium in which the immature embryos from the self-pollinated (compatible) tartary flowers were able to mature and germinate. No embryo development was observed after cross-pollination. The interspecific incompatibility is attributed to the failure of gametes to fuse.Abbreviations BAP benzylaminopurine - IAA indoleacetic acid  相似文献   

9.
Summary CertainPhaseolus vulgaris L. ×P. lunatus L. crosses were performed to study the effect of maternal heterozygosity on development and growth of the interspecific hybrid embryos. Interspecific embryos had a much slower growth rate in vitro compared with embryos derived from self-pollination ofP. vulgaris parents. Thus, interspecific embryos could be identified by growth rate in vitro. TheP. vulgaris maternal genotype affected both the number and size of 15-day-old interspecific embryos. Specifically, 76 Spartan Arrow produced significantly more interspecific embryos than did Great Northern as the seed parent, while maternal intraspecific hybrids produced smaller embryos than did maternal pure lines. There were no reciprocal differences between hybrid maternal parents for embryo number or size. Embryo size at excision and final size after culturing were closely correlated (r2=+0.93). The crossP. vulgaris 76 Spartan Arrow ×P. lunatus P.I. 214170 produced both the largest mean size at excision and the fastest growth in culture, indicating that specific combining ability affected both characteristics.Journal Paper No. J-12208 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 2495  相似文献   

10.
Black rot is a bacterial disease of Brassica oleracea caused by Xanthomonas campestris pv. campestris. Resistance to the major black rot races 1 or 4 has been identified in related Brassica species including B. carinata and B. napus. In this study, two B. juncea accessions (A 19182 and A 19183) that are resistant to races 1 and 4 of Xcc were used as maternal and paternal parents to generate interspecific hybrids with B. oleracea cultivars. Interspecific hybrids were recovered using the embryo rescue technique and confirmed through inheritance of paternal molecular markers. Twenty-six interspecific hybrid plants were obtained between A 19182 and B. oleracea cultivars, but no interspecific hybrids were obtained using A 19183. Although interspecific hybrid plants were male sterile, they were used successfully as maternal parents to generate backcross plants using embryo rescue. All hybrid and BC1 plants were resistant to black rot races 1 and 4.  相似文献   

11.
Summary Four different hybridization experiments were carried out to obtain interspecific hybrids with Spanish cultivars of lentil (Lens culinaris M.). In hybridization experiments I and II, undertaken with only pollination and pollination with the addition of gibberellic acid after fertilization, respectively, no lentil hybrids were recovered. A single interspecific hybrid with L. odemensis was obtained in experiment III using the embryo rescue protocol of Cohen et al. (1984), in this case, a crossing efficiency of 0.11% and a rescue efficiency of 2.5% were obtained. Hybridization experiment IV used a specific embryo rescue protocol developed in this study. In this experiment, ovule-embryos of 18 DAP were cultured on MS salts with 1% sucrose and 1 μ M IAA + 0.8 μ M KN; after two weeks, embryos were released from the ovular integuments and cultured on the same medium for another two weeks in upright position. Afterwards, the embryos were transferred to test tubes containing the same medium and one month later plantlets were obtained. Using the above protocol, out of a total of 1707 pollinations, 6 interspecific hybrids with L. odemensis, 2 with L. nigricans and one with L. ervoides were recovered, yielding on average a crossing efficiency of 0.53% and an average rescue efficiency of 8.26%. Taking into consideration only the interspecific crossing blocks in which hybrids were recovered, the crossing efficiency with L. odemensis was 9%, while with both L. nigircans and L. ervoides the crossing efficiencies were 3%. Rescue efficiencies based on hybrids recovered per number of ovules cultured ranged between 50–100%.  相似文献   

12.
Formation of embryo autonomy of strawberry, plant regeneration fro membryo components, plant freezing conditions in vitro and the possibility to differentiate objectively genotypes by freezing them in vitro and in vivo were studied to create strawberry screening technology in vitro for cold resistance. It was established that autonomy of strawberry embryos manifests itself not earlier than on 14–16th day after pollination and full autonomy is reached on 20–22nd day. Plants regenerated from 26 days old embryos grew most intensively. At the highest rate strawberry plants regenerated from an isolated embryo axis on MS medium without phytohormones, and from rescued cotyledons x on the medium with 1.0 BA and 0.5 NAA. The temperature interval, at which genotypes differentiated according to cold resistance in vitro, was -8 to 12 °C. Differentiation of strawberry genotypes according to this character conformed to their differentiation in vivo, provided hardening proceeded not less than 21 days. The correlation between cold resistance in vitro and in vivo reached 0.93. Domination of cold resistance manifested itself in strawberry seedlings from various crossing combinations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
Summary Various genes for disease resistance identified in wild Lactuca are difficult, even impossible to exploit in lettuce breeding, due to sexual incompatibility between L. sativa and wild Lactuca sp. We adapted two cellular biology techniques to overcome these interspecific barriers: in vitro embryo rescue and protoplast fusion. In vitro rescue of immature embryos was used successfully for sexual hybridization between L. sativa and L. virosa. Vigorous hybrid plants were produced between L. sativa and seven accessions of L. virosa. Protoplast fusion permitted the regeneration of somatic hybrids between L. sativa and either L. tatarica or L. perennis. Hybrids between L. sativa and L. tatarica were backcrossed to L. sativa.  相似文献   

14.
Summary Interspecific crosses between Cucumis metuliferus Naud. and C. anguria L. were obtained through embryo culture. Embryos in the rabbit-ear to advanced fluke-shaped stages were rescued 34–99 days after pollination. Plants were obtained through direct embryo culture, and through somatic embryogenesis from immature embryos. For direct embryo culture, fluke-shaped embryos were stored in sterile water in darkness for three days at 25C prior to transfer on Murashige and Skoog (MS) culture medium plus 1.0 M 6-benzylamino-purine. Multiple plants were obtained from single embryos through somatic embryogenesis of rabbit-ear stages on MS plus 10 M indole-3-acetic acid and 5 M 6-benzylamino-purine. Evidence of hybridization included leaf shape intermediate between the two parents, penduncle shape prior to fertilization which resembled the male parent, low pollen viability and isoelectric focussing of protein bands for acid phosphatase of leaf extracts.  相似文献   

15.
Summary Hybridizations between three lines of the common bean (Phaseolus vulgaris L.) and two lines of the lima bean (P. lunatus L.) were attempted in order to transfer characters from the lima bean to the common bean. A total of 115 interspecific hybrid embryos were rescued and cultured, and 7 plantlets were eventually transferred to soil. The most compatible cross was Edogawa XPI164891, which had a high proportion of expanded ovules, and from which we obtained one mature interspecific hybrid. In general, morphological characters of the hybrid were intermediate between the parents, and the chromosome number of the hybrid was 2n=22 the same as that of both parents. The hybrid nature of the progeny plant was confirmed by restriction endonuclease analysis of rDNA. Species specific fragments were detected when total DNA was digested by BamHI, and BamHI-digested total DNA of the hybrid contained all fragments from both parents. Selves and backcrosses were attempted, but no progeny were obtained. The only hybrid obtained was completely sterile and meiosis highly irregular.  相似文献   

16.
Summary Sixty-six chrysanthemum (Dendranthema grandiflora) inbred selections, noninbred cultivars and hybrids, and D. makinoi were the base populations from which up to three generations of inbreds were obtained using multiple plant descent. Each parent possessed pseudo-self compatibility (PSC), which allowed seed set following self pollination. Rapid-generation cycling (laboratory seed ripening to heart stage and subsequent embryo rescue) reduced generation time and minimized confounding maternal with zygotic inbreeding depression during post heart-stage seed development. Selection criteria were male/female fertility and PSC. Two stages of the life cycle were chosen to evaluate inbreeding depression: germination (seed development to germination) and survivorship (fertile individuals at anthesis). PSC was environmentally interactive and genotype dependent, causing variable levels of self seed set between and within populations and generations. By the end of the second generation, families from all noninbred cultivars, D. makinoi, and one F1 hybrid were eliminated from the experiment due to self incompatibility and/or inbreeding depression. Post-germination inbreeding depression was severe in several advanced inbreds. Inbred progeny of most F1 or F2 hybrids expressed less or equal amounts of inbreeding depression compared to advanced inbreds. Linear regression coefficients for either germination or survivorship on percent homozygosity were negative. Correlation coefficients between percent germination and survivorship (as a percent of seed set) were highly significant for Minnesota inbreds (r=0.67, P0.002) and hybrids (r=0.67, P0.006). The correlation coefficient was higher when percent germination and survivorship (as a percent of germinated seedlings) were compared (r=0.95, P0.001).Abbreviations F Fisher's Coefficient of Inbreeding - IBD Inbreeding Depression - PSC Pseudo-self Compatibility - RGC Rapid Generation Cycle - SI Self Incompatibility  相似文献   

17.
The primary aim of this study was to optimize in vitro culture protocols to establish an efficient reproducible culture system for different Brassica interspecific crosses, and to synthesize yellow-seeded Brassica napus (AACC) for breeding and genetical studies. Reciprocal crosses were carried out between three B. rapa L. ssp. oleifera varieties (AA) and five accessions of B. oleracea var. acephala (CC). All the parental lines were yellow-seeded except one accession of B. oleracea. Hybrids were obtained through either ovary culture from crosses B. rapa × B. oleracea, or embryo culture from crosses B. oleracea × B. rapa. A higher rate of hybrid production was recorded when ovaries were cultured at 4–7 days after pollination (DAP). Of different culture media, medium E (MS with half strength macronutrients) showed good response for ovaries from all the crosses, the highest rate of hybrid production reaching 45% in B. rapa (1151) × B. oleracea (T2). In embryo culture, the hybrid rate was significantly enhanced at 16–18 DAP, up to 48.1% in B. oleracea (T3) × B. rapa (JB2). The combinations of optimal DAP for excision and media components increased recovery of hybrids for ovary and embryo culture, and constituted an improved technique for B. rapa × B. oleracea crosses. In addition, yellow seeds were obtained from progenies of two crosses, indicating the feasibility of developing yellow-seeded B. napus through the hybridization between yellow-seeded diploids B. rapa and B. oleracea var. acephala.  相似文献   

18.
Summary In vitro tillers of over 1000 genotypes from nine contrasting Lolium perenne cultivars were cultured on various media containing the synthetic cytokinin, 6-benzylaminopurine (BAP), in order to determine the effect on tillering. The cultures were assessed after seven weeks for survival, tiller production, size and vigour. Added auxins 2,4-dichlorophenoxyacetic acid (2,4-D) and -napthaleneacetic acid (NAA) had no consistent beneficial effects.A significant relationship was found between in vitro tiller production and cultivar heading date. Genotypes of early-heading, less persistent cultivars produced more tillers than genotypes from late heading more persistent cultivars. This was consistent with the generally higher in vitro tiller production in the biennial species Lolium multiflorum cultured on similar media.  相似文献   

19.
Summary An early postfertilization ovule culture technique in Alstroemeria was described in which young ovules were cultured in vitro two days after pollination. This resulted in the direct production of seedlings in a normally incongruous cross combination. A histological study of the in vitro cultured ovules revealed the development of the embryo inside the ovule in the absence of normal endosperm. The in vivo grown ovules showed a total breakdown of the developing seed within four weeks after pollination due to a postfertilization barrier. This ovule culture technique was applied in a diallel cross of seven Alstroemeria species, five from Chile and two from Brazil. The selfings and the reciprocal crosses between the Brazilian species A. inodora and A. brasiliensis were congruous and gave seed set. The cross A. inodora x A. pelegrina gave viable seeds. In all other 39 combinations no viable seeds were harvested. In those cross combinations both pre-and postfertilization barriers were found. After early ovule culture hybrid plants were obtained in 27 of the 39 incongruous species combinations of the diallel.Abbreviations DAP days after pollination - MS medium medium according to Murashige & Skoog (1962)  相似文献   

20.
The first success at interspecific hybridization between cultivated sunflower(H. annuus) and a diploid perennial species, H. simulans is reported. The F1s from both direct and reciprocal directions exhibited dominance of the wild species phenotype and were pollen sterile. Meiosis was irregular in the F1 hybrids and both univalents and multivalents were observed. Multiplication of the interspecific hybrids was achieved through in vitro culture of nodal sections on Murashige & Skoog medium supplemented with 0.5 mg l-1 benzyladenine. Fertility of the interspecific hybrids was improved by subjecting the in vitro proliferating shoots to 0.001% colchicine incorporated in the shoot multiplication medium. The amphiploids serve as fertile bridges and facilitate interspecific gene transfer through conventional breeding. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号