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1.
青花菜小孢子发育时期与花器形态的相关性 总被引：4，自引：0，他引：4
对青花菜小孢子发育时期细胞学特征及其与花器外部形态的相关性展开研究,试图从花器的外部形态特征来推断小孢子的发育时期,最终目的是为花药或游离小孢子培养研究提供科学依据。结果表明,青花菜小孢子发育经历四分体时期、单核早中期、单核靠边期和双核期共4个时期,供试3个青花菜各时期细胞学特征存在明显差异。青花菜小孢子发育时期与花蕾大小和花药颜色等指标密切相关。供试青花菜花蕾纵径为10.52~11.05 mm,花蕾横径为3.64~4.25 mm,花药长度为2.85~2.87 mm,花药宽度为0.95~0.96 mm,且花瓣微露出花萼,花瓣和花药均为淡黄色时,80%以上的小孢子发育至单核靠边期。 相似文献
2.
É. Darkó J. Fodor S. Dulai H. Ambrus A. Szenzenstein Z. Király B. Barnabás 《Journal of Agronomy and Crop Science》2011,197(6):454-465
To improve the abiotic stress tolerance of maize (Zea mays L.), doubled haploid (DH) plants were produced by in vitro selection of microspores exposed to tert‐butyl hydroperoxide (t‐BuOOH) as a powerful prooxidant This study investigated the tolerance of the progenies of t‐BuOOH‐selected DH lines to oxidative stress, cold and drought in controlled environment pot experiments by analyses of photosynthetic electron transport and CO2 assimilation processes, chlorophyll bleaching and lipid peroxidation of leaves. Our results demonstrated that the t‐BuOOH‐selected DH plants exhibited enhanced tolerance not only to oxidative stress‐induced by t‐BuOOH but also to cold and drought stresses. In addition, they showed elevated activities of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase and glutathione S‐transferase when compared with the DH lines derived from microspores that were not exposed to t‐BuOOH and to the original hybrid plants. The results suggest that the simultaneous up‐regulation of several antioxidant enzymes may contribute to the oxidative and cold stress tolerance of the t‐BuOOH‐selected DH lines, and that the in vitro microspore selection represents a potential way to improve abiotic stress tolerance in maize. 相似文献
3.
本文对栽培密度不同的三个春小麦(Triticum aestivum L.)品种的小孢子和花粉发育进行了细胞学比较研究.结果表明:(1)在花粉母细胞时期.稀植小麦的小孢子发育略快于密植的.即当稀植小麦花粉母细胞开始减数分裂、药壁绒毡层开始解体时.密植小麦花粉母细胞刚形成.药壁完整;(2)到二、四分体时期、稀植小麦花粉母细胞发育加快.当其90%形成二、四分体时,密植小麦花粉母细胞才有50%将分裂成二分体.仅部分形成了二分体;(3)当小孢子发育到单核靠边期.稀植的主穗和分蘖穗发育越来越快.并有分蘖穗赶上主穗的趋势;而密植的分蘖穗发育减慢以至停止. 相似文献
4.
Efficient production of doubled haploid wheat plants by in vitro treatment of microspores with trifluralin or APM 总被引：4，自引：0，他引：4
Isolated microspore cultures from two doubled haploid (DH) lines of wheat, Triticum aestivum L., were used to develop an in vitro chromosome-doubling protocol. During the initial 24 h or 48 h of culture the microspores were treated with either of the two antimicrotubule herbicides trifluralin or amiprophos-methyl (APM) in concentrations ranging from 0.1 μM to 10μM. Untreated control cultures yielded 209 embryos per 100000 microspores, which is the equivalent of one spike. Among the regenerated plantlets 67% were green, and 15% of the flowering plants were spontaneously chromosome doubled. Treatments with both the herbicides had a significant effect on chromosome doubling, measured as the percentage of fertile regenerants. With the best combination of treatment duration (48 h) and herbicide concentration (10/μM) the percentage of fertile plants among regenerants could be increased up to 74% with APM and up to 65% with trifluralin. The largest numbers of DH plants per spike could be obtained with herbicide concentrations at 1–3 μM. Treatments with either herbicide at these concentrations resulted in an estimated average between the two genotypes of 27 DH plants per 100 000 microspores. These results demonstrate the high potential of APM and trifluralin as chromosome-doubling agents in isolated microspore cultures. The in vitro treatment integrated into tissue culture procedures will constitute an efficient method for chromosome doubling in future wheat breeding 相似文献
5.
Results on the induction of haploidy in tomato via both gynogenesis and microspore embryogenesis in vitro are far from satisfactory.
The number of reports available on the gynogenic induction via in vitro non-fertilized ovary culture, wide hybridization and
the use of irradiated pollen are limited. The main reason for this may be the difficulty experienced in working with this
species. Therefore, many failed attempts have not been reported. Non-fertilized ovary culture and wide hybridization using
Solanum sisymbriifolium Lam. as the male parent seem to be promising (Bal and Abak, Pak J Biol Sci 6:745–749, 2003a, b). Further efforts in this line may improve results obtained earlier. Several reports (Gresshoff and Doy, Planta 107:161–170,
1972; Sharp et al., Planta 104:357–361, 1972; Zamir et al., Plant Sci Lett 17:353–361, 1980; Chlyah and Taarji, Proc. Int. Symp. Plant tissue and cell culture application to crop improvement. 24–29 Sept. 1984; Jaramillo and Summers, J Amer Soc Hort Sci 115:1047–1050, 1990, HortScience 26:915–916, 1991; Summers et al., HortScience 27:838–840, 1992) are available on anther culture of tomato but a working protocol is yet to be developed. For the induction of anther callus,
anthers carrying microspores at the meiotic stages appear to be the most responsive. However, the callus and the regenerants
obtained were mainly of somatic origin. Somatic tissues of tomato anthers carrying the meiotic stages are highly responsive
to tissue culture manipulations in comparison to anther tissues of the later stages. Therefore, reports on the induction of
callus from anthers carrying early microspore stages should be met with caution. If culturing young anthers is of any help
then it may be that the anther tissues are nursing the microspores and bringing them to the responsive uninucleate stage.
Following the first report by Sharp et al. (Planta 104:357–361, 1972) on the induction of microspore embryogenesis, using a modified version of the microspore culture, reports concentrated only
on anther culture (reviewed by Chlyah et al., Haploids in crop improvement I. Biotechnology in agriculture and forestry 12.
Springer-Verlag, Berlin, 1990). Based on findings reported by Yinnan et al. (J Agric Biotechnol, , 1999) and Bal and Abak (Biotechnol Biotechnol Equip 19:35–42, 2005) on the induction of symmetrical division of microspore nuclei from uninucleate microspores, the formation of multicellular
structures and globular embryos, it is likely that the future of tomato haploidy lies in the technique of isolated microspore
culture. 相似文献
6.
Isolated plant microspores, when stressed and cultured in vitro, can be diverted from their normal gametophytic pathway towards
sporophytic development, with the formation of haploid embryos and ultimately doubled-haploid plants. This process is called
androgenesis or microspore embryogenesis, and is widely used in plant breeding programmes to generate homozygous lines for
breeding purposes. Protocols for the induction of microspore embryogenesis and the subsequent regeneration of doubled haploid
(DH) plants have been successfully developed for more than 200 species. These practical advances stand in stark contrast to
our knowledge of the underlying molecular genetic mechanism controlling this process. The majority of information regarding
the genetic and molecular control of the developmental switch from gametophytic to sporophytic development has been garnered
from four intensely studied (crop) plants comprising two dicotyledonous species, rapeseed (Brassica napus) and tobacco (Nicotiana tabacum), and two monocotyledonous species, wheat (Triticum aestivum) and barley (Hordeum vulgare). In these species the efficiency of microspore embryogenesis is very high and reproducible, making them suitable models
for molecular studies. In the past, molecular studies on microspore embryogenesis have focussed mainly on the identification
of genes that are differentially expressed during this developmental transition and/or early in embryo development, and have
identified a number of genes whose expression marks or predicts the developmental fate of stressed microspores. More recently,
functional genomics approaches have been used to obtain a broad overview of the molecular processes that take place during
the establishment of microspore embryogenesis. In this review we summarise accumulated molecular data obtained in rapeseed,
tobacco, wheat and barley on embryogenic induction of microspores and define common aspects involved in the androgenic switch. 相似文献
7.
Sixteen lines of Brassica carinata were evaluated for microspore culture and plant regeneration. The highest values of cell division and embryo yield resulted from buds between 2.5 and 3.5 mm long with 3 days of pretreatment at 32°C and plating densities of 100 000-150 000 microspores/ml. Ten out of 16 lines tested (63%) responded positively to microspore culture. In all breeding and F1 lines, both cell division and embryo yield varied over a wide range, but embryogenic response was higher in F1 lines than in the breeding lines. 相似文献
8.
Wheat anther cultures have a history of almost 30 years and are nowemployed efficiently in many countries of the world for the developmentof doubled haploid lines for breeding. The present paper discusses keyquestions of the elaboration and perfection of the method: cytologicalaspects of in vitro androgenesis, the conditions required for theembryogenic development of microspores and the applicability of anthercultures in the Martonvásár wheat breeding programme. 相似文献
9.
玉米CMS-S小孢子败育过程中的细胞程序性死亡 总被引：7，自引：2，他引：7
以玉米（Zea mays L.）S型细胞质雄性不育系(CMS-S)的一对近等基因系S-Mo17Rf3Rf3 和S-Mo17rf3rf3为材料，采用TdT介导的dUTP DNA末端标记（TUNEL）、细胞色素C免疫原位杂交和DNA寡聚核小体片段电泳等方法，分别在细胞学水平和DNA水平上研究了玉米CMS-S小孢子败育的细胞程序性死亡（PCD）过程。结果表明，在花粉母细胞减数分裂后的四分体解离时期，不育花药的绒粘层细胞较可育花药提前裂解；在不育系S-Mo17rf3rf3花药和花粉S-rf3中均明显出现PCD过程的DNA片段化以及线粒体细胞色素C外渗的现象，证明了玉米CMS-S的花粉败育与花药绒粘层细胞的提前凋亡和小孢子细胞的程序性死亡有关。 相似文献
10.
Aluminium (Al) toxicity is a major constraint to crop productivity in acidic soils. A quantitative trait locus (QTL) analysis
was performed to identify the genetic basis of Al tolerance in the wheat cultivar ‘Chinese Spring’. A nutrient solution culture
approach was undertaken with the root tolerance index (RTI) and hematoxylin staining method as parameters to assess the Al
tolerance. Using a set of D genome introgression lines, a major Al tolerance QTL was located on chromosome arm 4DL, explaining
31% of the phenotypic variance present in the population. A doubled haploid population was used to map a second major Al tolerance
QTL to chromosome arm 3BL. This major QTL (Qalt
CS
.ipk-3B) in ‘Chinese Spring’ accounted for 49% of the phenotypic variation. Linkage of this latter QTL to SSR markers opens the possibility
to apply marker-assisted selection (MAS) and pyramiding of this new QTL to improve the Al tolerance of wheat cultivars in
breeding programmes. 相似文献
11.
Summary Octoploid Tritileymus was the partial amphiploid obtained from Triticum aestivum × Leymus mollis, its chromosome constitution was 14 Leymus chromosomes and 42 wheat chromosomes. In the pollen development of Tritileymus, some abnormalities were observed, such as the absence of tetrad formation, cytomixis of microspores, irregular shape of
some microspores and multi-germination pores, symmetrical first mitosis, chromosomes or chromatids randomly dispersed in the
cytoplasm of microspore. 相似文献
12.
Regeneration of fertile doubled haploid plants from colchicine-supplemented media in wheat anther culture 总被引：6，自引：0，他引：6
I. Zamani G. Kovács E. Gouli-Vavdinoudi D. G. Roupakias B. Barnabás 《Plant Breeding》2000,119(6):461-465
The effect of colchicine added to induction medium for the production of fertile doubled haploid plants after in‐vitro anther culture was studied in wheat, Triticum aestivum L. For this, one winter and two spring wheat varieties were used. Anther cultures of the three genotypes were treated with 0.03% colchicine for 3 days at the beginning of microspore induction. Colchicine had no significant effect on anther response and embryoid production of the genotypes examined. However, in the winter wheat genotype ‘Mv Szigma’, colchicine caused a significant reduction in microspore‐derived structures. A significant decrease was also observed in plant regeneration ability of two genotypes (‘Vergina’ and ‘Acheloos’) after colchicine treatment. In addition, a significant reduction of the albinos produced was observed in all genotypes after olchicine treatment. In contrast, the regenerants obtained from the colchicine‐supplemented induction media produced significantly higher percentages of fertile plants in all genotypes. However, the level of fertility, was significantly different among the fertile plants obtained. This, together with the observation that in the case of the winter wheat variety the colchicine treatment resulted in 100% completely fertile plants with a high seed‐setting ability indicate that there is space for further improvement of the method when it is applied to spring cultivars. Finally, the increased number of seeds per 100 plated anthers obtained from all three genotypes after colchicine treatment, clearly demonstrates that the addition of colchicine to induction medium was superior to the conventional anther culture method and it could therefore be introduced into wheat breeding programmes. 相似文献
13.
Microspore culture was employed to measure the relative efficiencies of anther culture and isolated microspore culture for the regeneration of embryoids and plants of Brassica napus. The yield of embryoids and plants was at least 10-fold greater from isolated microspores than from anther cultures. Approximately 1400 microspore-derived homozygous line's, the parental varieties and the corresponding F2 plants were grown in a field trial. Important agricultural characteristics, such as morphological homogeneity, growth rate, onset of flowering and seed setting were evaluated subjectively and seed yield and glucosinolate content of individual plants were determined. The relative concentrations of up to S different glucosinolates in these seeds were measured via an automated high performance liquid chromatography (HPLC) system. The alkenyl and indole glucosinolates, the two most important categories of glucosinolates, were found in varying proportions and were independently determined in these line's. Our results do not support the previously suggested connection between low concentrations of glucosinolates and weak growth and/or poor seed yield. Additionally, no evidence was found that the lines derived from isolated microspore culture were subjected to unexpected selection pressures that might adversely affect the diversity of the lines obtained. These results demonstrate that microspore culture is a powerful tool not only for genetic analysis bur also for practical plant breeding. 相似文献
14.
以探讨大麦单倍体细胞水平的耐冷、耐NaCl性与植株水平抗病、耐盐性的相关性为目的，用赤霉病抗性、耐盐性不同的大麦为供试材料，比较了它们的离体培养花药及小孢子对低温、NaCl预处理的培养反应。结果表明：感病材料低温（5℃）预处理17d的花药培养愈伤组织诱导率比未经低温预处理的低，抗病材料则有一定的升幅。用NaCl溶液直接处理游离小孢子，所有供试材料的小孢子存活率随处理浓度升高不断下降，耐盐材料的存活率下降幅度比盐敏材料的小，且抗病材料的降幅比感病材料的小。说明：供体植株水平的抗病、耐盐性在花药、小孢子水平上也能有所表现。 相似文献
15.
In this work we address two aspects of eggplant flower biology potentially involved on the efficiency of anther culture: the
selection of the best floral stage to extract anthers for culture, and the effect of heterostyly in the identification of
suitable buds and anthers. For 12 different accessions, we determined morphological criteria (length ranges) to identify buds
and anthers enriched in vacuolate microspores and young bicellular pollen, the stages most responsive to embryogenesis induction.
While these microspore/pollen stages were the most responsive when isolated and cultured in liquid medium, we observed that
culture of anthers containing these stages is not the best choice. Instead, the highest response was found for younger anthers,
containing mostly young and mid microspores. We analyzed eggplant anther walls and found that their particular thickness may
be behind this apparent discrepancy, since they may delay the diffusion of inducing factors to the anther locule, reducing
their effect over inducible microspores. Thus, the culture of younger anthers would allow for younger microspores to grow
up to the inducible stages while factors are entering the locule. We also analyzed the embryogenic response of short and long-styled
buds present in Cristal, a heterostylic cultivar. Our results demonstrated that each floral morph produced buds and anthers
of different lengths, but equally useful for anther culture, since similar amounts of embryos were produced. The practical
application of these results may improve the efficiency of anther culture not only in these cultivars, but in others also
presenting thick anther walls and heterostyly. 相似文献
16.
The origin of unreduced microspores due to aberrant cytokinesis in the meiocytes of potato and its genetic significance 总被引：1，自引：0，他引：1
Summary In 7 aneuhaploids of Solanum tuberosum and one clone of S. phureja the mechanism of unreduced microspore production has been studied. It has been observed that the unreduced microspores are produced not only by nuclear restitution at meiosis but also by aberrant cytokinesis in the meiocyte. The size and the number of nucleoli that are present in young microspores at the sporad stage give a fairly reliable indication of the ploidy level and the type of nuclear restitution that has occurred. These two aspects are helpful to deduce the meiotic events that have probably led to the formation of unreduced microspores in some cases. It has been found that triads and dyads are formed regardless of the type of nuclear division or restitution, indicating that cytokinesis is independent of karyokinesis to some extent. Cytological basis of unreduced microspore formation in diploid forms of potato appears to be more complex than it was supposed earlier. 相似文献
17.
高粱A2型细胞质雄性不育系小孢子发生的细胞学观察和减数分裂染色体行为分析 总被引：1，自引：0，他引：1
高粱A2型细胞质雄性不育性（CMS）的细胞质来源于IS12662C, A2细胞质杂交种目前已用于生产。本文以A2/B2V4为材料，对A2 CMS小孢子败育过程作了细胞学观察，并对小孢子败育过程中减数分裂的染色体行为作了分析。研究发现，在A2雄性不育系A2V4的花药发育过程中，绒毡层细胞不形成或提前解体；绒毡层细胞畸形化；绒毡层细胞虽发育正常，但小孢子母细胞减数分裂行为异常；这些都导致小孢子退化。A2细胞质雄性不育花粉母细胞减数分裂行为从后期Ⅰ开始出现异常，同源或姊妹染色体向两极分离时滞后或不分裂；染色体多倍化；一个细胞内出现多核和多核仁现象，最终导致小孢子败育。 相似文献
18.
Summary Our objective was to determine the average numbers of pollen grains from fertile plants (Ms
1) and the average numbers of coenocytic microspores from genetic male sterile plants (ms
1
ms
1) in soybeans, Glycine max L. Merr. Comparisons were made between the average numbers of pollen grains and the average numbers of coenocytic microspores with respect to environment where plants were grown and to stamen position in the flower. Five male sterile lines were used. They included the North Carolina ms
1 mutant, the cultivar Hark with the ms
1 gene, and mutants identified as the Urbana, Tonica, and Ames male steriles. Three environments used were the Agronomy Farm, University of Georgia, Athens, Georgia; the Agronomy and Agricultural Engineering Research Center, Iowa State University, Ames, Iowa; and the Agronomy Greenhouse, Iowa State University, Ames, Iowa.Pollen production from fertile plants varied from 374 to 760 pollen grains per anther among genetic lines and environments. This variation may be an important consideration in selecting a male parent to use as a pollinator for hybrid seed production.Among fertile plants, the average numbers of pollen grains per anther of the separate stamen and and of the lower whorl of stamens were significantly different only in greenhouse-grown plants. Among male sterile plants, the average numbers of coenocytic microspores per anther of the separate stamen and of the lower whorl of stamens were significantly different in three genotype x environment combinations. These three exceptions did not conform to any genetic or environmental pattern. Deviations from the expected ratio of 4 pollen grains from fertile plants: 1 coenocytic microspore from sterile plants were attributed to initial differences in the average number of microspore mother cells between the two genotypes.Joint contribution: Agricultural Research Service, USDA, North Central Region, and Journal Paper No. J-8910 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa 50011; Project 2107. 相似文献
19.
Sc2053诱导小麦雄性不育形态学和细胞学观察 总被引：2，自引：0，他引：2
应用化学杂交剂Ｓｃ２０５３诱导小麦雄性不育的形态学和细胞学特征观察结果显示，经处理的小麦植株变矮，植株及麦穗呈现浅绿色，穗子呈爆裂状，花药不开裂，呈现雄性不育株的形态特征，这些特征可做为估算小麦群体化学杀雄效果即绝对不育率的依据。经Ｓｃ２０５３处理的小麦雄性不育有无花粉和花粉败育两种类型。无花粉型是在小孢子刚形成时发生败育，从而是产生无花粉的空壳型花药。花粉败育型是小孢子只发育到单核花粉，二胞花粉 相似文献
20.
Summary
Sorghum bicolor (L.) Moench is generally quite sensitive to salt and acid (high aluminium) soil stresses, but quite tolerant of drought stress. As with any stress phenomenon, intra-specific variability exists within the genus. In vitro cell selection and somaclonal variation offer an alternative to traditional breeding methodology for generating improved breeding lines for hybrid development. A field selection protocol was developed for the three soil stresses and inter-stress evaluations were conducted in an effort to find multiple, stress-tolerant genotypes. The acid soil-drought stress, super-tolerant selections were located by the R7 generation when exposed to a combined aluminium-drought stress field environment and when the regeneration population (number of regenerated lines from one callus source) was maintained at 15,000 plants or higher. A variant frequency of 0.1 to 0.2% for stress tolerance and acceptable agronomic traits among the surviving somaclones, provided an adequate number of phenotypes with desirable agronomic characteristics and a high level of soil stress tolerance. Subsequent research verified that the stress-tolerant regenerants had superior acid soil and drought stress tolerance to that of the donor parents, that their yield capabilities under stress were superior to their parents, and that their stress tolerance attributes were transferred in hybrid combinations. In vitro selection was not effective in increasing the number of field stress survivors. In fact, superior germplasms were developed from non-stressed callus or salt-stressed callus. In vitro selection reduced regeneration frequency and subsequent survival of plants under field stress. In vitro-stressed regenerants should be subjected only to non-stressed environments to maintain population numbers for field selection and thereafter should be subjected to stress environments during later (R5+) generations. The optimal strategy for the exploitation of somaclonal variation may be through short-term cell culture (< 12 months) with no attempt at in vitro selection. 相似文献