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1.
Agnieszka Kiełkowska Adela Adamus Rafal Baranski 《In vitro cellular & developmental biology. Plant》2014,50(3):376-383
In this work, we describe an improved protocol for induced parthenogenesis and ovule culture of carrot (Daucus carota L.). The effects of pollination with parsley pollen and/or 2,4-dichlorophenoxyacetic acid (2,4-D) treatment on the stimulation of parthenogenesis were studied using heterozygous donor plants of 30 varieties and breeding populations of carrots. Isolated ovules, cultured in vitro, enlarged and developed embryos or calli. The application of 2,4-D on pollinated flowers stimulated callus development but did not increase the frequency of embryo development from ovules and, thus, was not useful for increasing the frequency of haploid plant recovery. The efficiency of embryo development was accession-dependent and varied from 0 to 24.29%. In optimized conditions, most accessions responded by embryo development exclusively. The highest frequency of embryo development was observed from ovules excised from ovaries 20–22 d after pollination with parsley pollen. Among several media used for ovule culture, 1/2-strength Murashige and Skoog medium with 0.06 μM indole-3-acetic acid (IAA) was the best. It allowed the production of embryos at a similar frequency as on the media supplemented with kinetin, gibberellic acid, putrescine, or thidiazuron, but restricted callus development. Most plants obtained were haploids and diploids derived from parthenogenesis, as evidenced by homozygosity at three independent loci based on isozyme and PCR analyses. In total, considering haploids and embryo-derived homozygous diploids together, 72.6% of regenerated plants were of gametic origin. 相似文献
2.
Influences of Cross Pollination on Pollen Tube Growth and Fruit Set in Zuili Plums (Prunus salicina) 总被引:1,自引:0,他引:1
Zuili plum (Prunus salicina L.) trees usually set fruit poorly, although they produce high quality fruit. To elucidate the causes of the poor fruit set, pollen tube growth into pistils and fruit set percentage were investigated after cross-, self- and open-pollination. Ovule development in Zuili pistils was also investigated. Pollen tube penetration into the ovules via the obturator and micropyle was best when Zuili pistils were pollinated by cv. Black Amber (P. domestica) pollen grains, although cross-pollinations with Hongxinli and Miili (P. salicina) pollen were more effective than self- and open-pollination. The fruit set percentage was also highest in pistils pollinated with Black Amber pollen grains. Morphological observation of Zuili pistils revealed that the trees produce "double pistils", developing two ovaries from a basal pistil, at a rate as high as 28%. In such abnormal pistils, most ovules were lacking an embryo sac or were entirely degenerated. The percentage of normally developed ovules was 24.3% and 8.9% in normal and double pistils, respectively. From these results, we conclude that the main causes of poor fruit set of Zuili plums are a lack of effective cross-pollination and the production of high percentages of double pistils in which normally developed ovules are scarcely formed. 相似文献
3.
Winter rapeseed (Brassica napus, cv. Samouraï) flowersearly in spring and, under field conditions, short freezingperiods can occur. Unacclimatized plants were freeze-stressed(3°C for 4 h) at different developmental stages ofbuds, open flowers and seeds. The dissection of pistils from stressed plants showed that freezingresults in shrivelled ovules. We assessed freezing injury onthe basis of per cent of shrivelled ovules: ovule sensitivitybegins early (8 d before anthesis) but increases up to anthesis.Crosspollination of stressed pistils with non-stressed pollenshowed that recording of freeze-injured ovules is a good methodfor early estimation of the effect of stress on seed yields. On the other hand, stress does not reduce the viability of pollen,except when it was applied at the binucleate pollen stage. Useof frozen pollen x nonstressed pistils has little effect onseed yields. Freeze injury on seeds was assessed by seed filling:seeds are very susceptible just after fertilization until 20d after fertilization (DAF). Freezing seems to inhibit seedfilling. A germination test of stressed seeds during their developmentindicated that embryo viability is not affected if the stressoccurs after 35 DAF. As the embryos develop, resistance to stressincreases. Key words: Brassica napus, rapeseed, freeze injury, pollen and ovule, seed filling 相似文献
4.
Summary Plants derived from anther culture are theoretically haploid, but diploid plants are also known to arise. Anther culture-derived
diploid plants are usually homozygous and are believed to be due to spontaneous doubling of chromosomes in either microsporocytes
or callus cells during the culture process. However, heterozygous diploid regenerants may also arise from a) regeneration
from cultured somatic cells, b) mutation occurring during or after a spontaneous doubling event, c) fusion of unlike haploid
cells in chimeric callus, and d) regeneration from diploid microsporocytes resulting from aberrant meioses. This study was
designed to elucidate the frequency and origin of diploid regenerants from rice anther culture. Regenerants were obtained
from 11 F1 genotypes. Progeny testing detected heterozygosity in 7 out of 211 regenerants. Each of the heterozygous regenerants were
from ‘Calrose 76’/waxy ‘M-101’, Half of the diploid regenerants from this cross were heterozygous. No heterozygous regenerants
arose from the other 10 F1 genotypes. Progeny testing indicated that two of the heterozygous regenerants were as heterozygous as the F1 plants for three parental characters. The other five regenerants exhibited decreased levels of heterozygosity. One of the
heterozygous regenerants exhibited evidence of mutation for a non-parental character. However, mutation is an unlikely cause
of the observed high levels of parental-type heterozygosity. No evidence for the occurrence of chimeric callus was detected,
making this an unlikely cause as well. The most likely origin of the observed partial heterozygosity is regeneration from
diploid microspores, which could also produce plants exhibiting complete parental-type heterozygosity. 相似文献
5.
S. Zdravković-Korać J. Milojević Lj. Tubić D. Ćalić-Dragosavac N. Mitić B. Vinterhalter 《Plant Cell, Tissue and Organ Culture》2010,101(2):237-244
A protocol has been developed for somatic embryogenesis and subsequent plant regeneration in Allium schoenoprasum L. Calli were induced from root sections isolated from axenic seedlings and cultivated on media containing either Murashige
and Skoog’s (MS) or Dunstan and Short’s mineral solution supplemented with 5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) in
combination with 6-benzylaminopurine (BA), 6-furfurylaminopurine (Kin) or thidiazuron (TDZ) at 1, 5 or 10 μM. The highest
frequencies of callus induction were achieved on media with 5 μM 2,4-D in combination with 5 μM TDZ or 10 μM BA (78.9% and
78.4%, respectively). Calli were then transferred to 1 μM 2,4-D, where compact yellow callus turned to segmented yellowish
callus with transparent globular somatic embryos at the surface. Calli that were previously grown on media with 5 μM 2,4-D
in combination with 10 μM BA or 10 μM TDZ showed the highest frequencies of embryogenic callus formation (45% and 42%) as
well as mean number of somatic embryos per regenerating callus. The choice of mineral solution formulation did not significantly
affect callus induction or embryogenic callus formation. The embryos could complete development into whole plants on plant
growth regulator (PGR)-free medium, but inclusion of Kin (0.5, 2.5 and 5 μM) in this phase improved somatic embryo development
and multiplication. Subsequently transferred to 1/2 MS PGR-free medium, all embryos rooted and the survival rate of the plants
in a greenhouse was 96%. 相似文献
6.
Mya Thuzar Apichart Vanavichit Somvong Tragoonrung Chatchawan Jantasuriyarat 《Acta Physiologiae Plantarum》2011,33(1):123-128
An efficient and rapid plant regeneration system through somatic embryogenesis was developed using 13-week-old zygotic embryos
of oil palm (Elaeis guineensis Jacq.) cv. ‘Tenera’. Zygotic embryos were cultured on MS and N6 media supplemented with 2.0 mg L−1 picloram, 2,4-D and dicamba. The highest embryogenic callus formation (32%) was observed on N6 medium with 2,4-D after 3 month
culture on callus induction medium. Somatic embryos were continuously formed from nodular calli on embryo maturation medium
[N6 + 0.1 mg L−1 2,4-D, 0.16 g L−1 putrescine, 0.5 g L−1 casein amino acids and 2.0 g L−1 activated charcoal(AC)] for 3–5 months. Histological analysis confirmed that embryo development occurred via somatic embryogenesis.
For plant regeneration, modified N6 medium (MN6) with AC (0.5 g L−1) without growth regulators, induced both shoot and root formation simultaneously with the highest regeneration rate of 56%.
This combined shoot and root induction protocol shortened the culture time to 9–12 months. Furthermore, after acclimatization,
more than 85% of transferred plants from our protocol developed successfully in the soil. 相似文献
7.
Summary Media components used for three stages of development: (1) callus maintenance, (2) maturation of embryos, and (3) conversion
of embryos to plants were shown to affect regeneration of plants for the commercially important red rose cultivar Kardinal.
Embryogenic callus was maintained for 5yr on either Schenk and Hildebrandt’s basal salts medium (SH) supplemented with 13.6
μM 2,4-dichlorophenoxyacetic acid (2,4-D) or Murashige and Skoog’s basal salts medium (MS) supplemented with 18.1 μM dicamba and 0.46 μM kinetin. Maturation of embryos was three times higher using callus maintained on the SH medium supplemented with 2,4-D while
conversion of cotyledonary-stage embryos to plants was significantly higher (10 times) using callus that had been maintained
on MS medium with dicamba and kinetin. Maximum maturation (13.5%), and conversion (15.2%), occurred when callus was cultured
on MS maturation medium without hormones. Cotyledonary-stage embryos cultured on MS conversion medium supplemented with abscisic
acid (5–20 μM) produced plants that survived at a significantly higher rate (two times) in the greenhouse than when embryos were cultured
without abscisic acid. The highest rate of plant regeneration occurred when embryogenic callus of ‘Kardinal’ was maintained
on MS medium supplemented with dicamba and kinetin, maturation of embryos occurred on MS maturation medium without hormones,
and conversion of cotyledonary-stage embryos occurred on MS conversion medium supplemented with abscisic acid. 相似文献
8.
Regeneration of albino shoots in cultured anthers of intermediate wheatgrass (Agropyron intermedium (Host) Beauv.) 总被引:3,自引:0,他引:3
Kangshen Yao Chen H. Chen Charles R. McMullen 《Plant Cell, Tissue and Organ Culture》1991,26(3):189-193
Shoots were regenerated from Oahe intermediate wheatgrass anthers cultured on Tsay's, N6, Yu-pei and 85D12 basal media supplemented with kinetin and 2,4-D or NAA. Androgenesis mainly started with symmetrical divisions of pollen nuclei immediately followed by cytokinesis. Formation of tetranucleate pollen grains resulting from asymmetrical divisions of the pollen nuclei was also noted. Tsay's medium was more effective for callus induction, while N6, Tsay's and Yu-pei differentiation media were equally effective for shoot regeneration in the calluses. All regenerants were albino.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- NAA
naphthaleneacetic acid 相似文献
9.
Response of twenty eight cultivars of durum wheat (Triticum turgidum var. durum) to immature embryo culture, callus production and in vitro salt tolerance was evaluated. For assessment of cultivars to salt tolerance, growing morphogenic calli were exposed to different
concentrations of NaCl (0, 0.3, 0.6, 0.9, 1.2, 1.5, 1.8 and 2.1% w/v) added to the culture medium during two subsequent subcultures
(4 weeks each). Comparison of cultivars for callus induction from immature embryo was based on callus induction frequency
and fresh weight growth of callus (FWG). While, for salt tolerance, the relative fresh weight growth (RFWG) and necrosis percent
of callus were used. There were significant differences among cultivars for potential of regeneration from immature embryo,
and ‘Shahivandi’ a native durum wheat cultivar originating from western Iran was superior among the cultivars tested. The
FWG distinguished cultivars more than callus induction frequency did for callus induction evaluation. Hence, a range of FWG
from 1.23 to 14.65 g was observed in ‘Mexical-75’ and ‘Omrabi-5’ cultivars, respectively. Growing calli derived from cultivars
‘PI 40100’ and ‘Dipper-6’ showed superiority for tolerating salinity under in vitro conditions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
XiaoPeng Fu ShuHua Yang ManZhu Bao 《In vitro cellular & developmental biology. Plant》2008,44(3):194-202
In this study, we aimed to maximize the rates of somatic embryogenesis achievable in anther cultures of Chinese pink (Dianthus chinensis L.) (2n = 2x = 30). The genotype of the donor plant was found to be a major factor in determining the success rate. Conditions
imposed during anther culture (notably medium composition and light conditions) and pretreatments (namely, cold, heat, and
mannitol incubations) were also found to influence somatic embryo induction. For example, the highest levels of embryogenic
callus induction were achieved when the donor buds had been cold pretreated and the subsequent anther culture was maintained
in darkness. Furthermore, there appeared to be an interaction of genotype with culture conditions. Thus, in cultures of the
cultivar (cv.) ‘Carpet’, the highest rates of embryogenesis were obtained when the anthers had received a 5-d heat-shock,
but such a thermal treatment did not generally produce a significant effect. Likewise, a 3-d mannitol pretreatment was optimal
only for the cross-hybrid line ‘HC’. Assessment of the ploidy of the plants regenerated from the anther cultures revealed
both diploid and tetraploid plants. Histological and cytological observations showed that all of these (both from n-pollen
and 2n-pollen lines) derived from anther wall cells. Spontaneous chromosome doubling was inferred to have occurred during
the embryogenic callus culture period. 相似文献
11.
In vitro induction, regeneration and analysis of autotetraploids derived from protoplasts and callus treated with colchicine in Citrus 总被引:2,自引:0,他引:2
Shao-Hua Zeng Chuan-Wu Chen Liu Hong Ji-Hong Liu Xiu-Xin Deng 《Plant Cell, Tissue and Organ Culture》2006,87(1):85-93
In the present paper attempts were made to induce chromosome doubling of ‘Meiwa’ kumquat (Fortunella crassifolia) protoplasts and ‘Frost’ navel orange (Citrus sinensis Osbeck) embryogenic callus via colchicine treatment. Colchicine decreased protoplast viability, delayed protoplast division and inhibited callus growth, indicating presence of toxicity to cells. Cell lines established from ‘Meiwa’ protoplasts treated with 0.01 and 0.1% colchicine for 8, 16 and 24 h at each concentration showed different responses when they were cultured on embryoid-induction medium. Flow cytometry (FCM) demonstrated that tetraploids were detected in cell lines and embryoids from all of the treatments, with the highest frequency being 19.23%. As for ‘Frost’, tetraploid cells were only detected when the callus was treated with 0.1% colchicine for either 4 or 8 days, from which plantlets were regenerated. FCM and chromosome counting confirmed them as true tetraploids. The diploid cells were more active in mitotic division during a 12-day culture and smaller in size than their tetraploid counterpart. Potential applications of the novel tetraploid germplasms obtained through in vitro chromosome doubling to citrus cultivar improvement are discussed. 相似文献
12.
Callus cultures initiated from shoot base explants of Curcuma aromatica Salisb. were maintained on Murashige and Skoog (MS) media supplemented with 2 mg dm−3 2,4-dichlorophenoxyacetic acid alone or with 0.5 mg dm−3 kinetin. Plantlets were regenerated from 60 and 180-d-old callus on MS media supplemented with 3 mg dm−3 benzyladenine and 0.5 mg dm−3 α-naphthalene acetic acid. Approximately 8–10 plantlets were produced after 30–40 d of culture per 50 mg of callus inoculated.
Out of 113 regenerants analyzed 85 plants were exclusively diploid and 28 were predominantly diploid revealing presence of
polyploid nuclei. Frequency of polyploid cells were more in regenerants obtained from 180-d-old callus then from 6-d-old callus
which might be attributed to the ageing of callus. 相似文献
13.
Brent Tisserat Toshio Murashige 《In vitro cellular & developmental biology. Plant》1977,13(11):799-805
Summary A factor that represses asexual embryogenesis has been observed in the Rutaceae, with particularly high concentrations in
the naturally monoembryonic cultivars. This investigation was an initial step towards identifying the factor.Citrus reticulata Blanco Ponkan mandarin nucellus explants andDaucus carota L. ‘Queen Anne's Lace’ callus were employed to examine effects of known plant growth regulators and to determine possible
identity of one or more of them with the repressive factor. The chalazal halves of ovules ofC. media L. ‘Citron of Commerce’ were used as control repressor source. Embryo initiation and growth of both test tissues were depressed
markedly by 2,4-D, abscisic acid and ethephon. Slight inhibitions were obtained with IAA, kinetin and gibberellic acid. Recovery
from the repressor did not occur readily inCitrus nucellus following recultures in citron-ovule-free medium; carrot callus resumed normal embryogenesis immediately upon transfer
to suppressor-free medium. The repression by natural sources apparently involved the combined action of some or all natural
hormones that are generically related to the above.
This paper is part of B. Tisserat's Ph.D. dissertation in Botany at the University of California, Riverside. The research
was supported in part by the Elvenia J. Slosson Fellowship in Ornamental Horticulture awarded to T. Murashige. 相似文献
14.
Daniela Lopes Paim Pinto Ana Maria Rocha de Almeida Mailson Monteiro Rêgo Maurecilne Lemes da Silva Evelyn Jardim de Oliveira Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2011,107(3):521-530
Mature zygotic embryos of three genotypes of Passiflora edulis Sims, including ‘FB-100’, ‘FB-200’, and ‘FB-300’ were incubated on a Murashige and Skoog (MS) (1962) medium supplemented with different concentrations (18.1–114.8 μM) of 2,4-diclorophenoxyacetic acid (2,4-D) and 4.4 μM of
6-benzyladenine (BA). MS basal medium and MS with BA induced germination of P. edulis embryos. The highest frequencies of embryogenic calli were observed when explants were incubated on MS medium supplemented
with 72.4 μM 2,4-D and 4.4 μM BA for ‘FB-200’, which showed the highest potential for embryogenic callus formation. Cytological
and histological analyses of pro-embryogenic callus revealed two distinct cell types: thin-walled, small, isodiametric cells
with large nuclei and dense cytoplasm, typical of intense metabolic activity; and elongated and vacuolated cells, with small
nuclei and less dense cytoplasm. Differentiation of somatic embryos was promoted on MS medium supplemented with activated
charcoal and indole-3-acetyl-l-aspartic acid (IAA-Asp) either with or without 2,4-D. However, no conversion of somatic embryos into plantlets was observed. 相似文献
15.
Hui Song Qun-Feng Lou Xiang-Dong Luo Joseph N. Wolukau Wei-Ping Diao Chun-Tao Qian Jin-Feng Chen 《Plant Cell, Tissue and Organ Culture》2007,90(3):245-254
Six experiments (including pretreatment, embryonic callus induction media, preculture conditions, embryo induction media,
embryo germination media, and genotypic effects) were conducted to develop an efficient cucumber (Cucumis sativus L., 2n = 2x = 14) anther culture protocol. Pretreatment and embryo induction were key factors for successful anther culture. Suitable
temperature stress depended on the ecotype, i.e., cucumbers from cold areas responded well to cold shock whereas those from
temperate areas responded well to heat treatment. The best medium for embryonic callus induction was MS medium supplemented
with 4.44 μM BA, 2.26 μM 2, 4-D, 4.64 μM KIN, 3% sucrose and 0.8% agar. For embryo induction, MS medium supplemented with
0.54 μM NAA, 13.32 μM BA, 3% sucrose and 0.8% agar was optimal, and for embryo germination MS medium containing 2.22 μM BA,
6% sucrose and 1.2% agar was best. Using this protocol, we produced callus from 16 genotypes and regenerated plants from three
of 20 evaluated. Three embryos per anther and 42 DH per 45 anthers (93% success) were obtained for cv. Ningjia No. 1, which
was an improved result over a previous report. The origin of regenerants from microspores was determined by cytological, morphological
and AFLP analyses. 相似文献
16.
Elena Rákosy-Tican Adriana Aurori Simona Vesa Krisztina-Maria Kovacs 《Plant Cell, Tissue and Organ Culture》2007,90(1):55-62
Sunflower, as one of the most important oil-producing crops, represents an important target for genetic improvement through
gene transfer or somatic hybridization. Unfortunately, sunflower is recognized as recalcitrant to in vitro culture. The aim
of our paper was to improve sunflower protoplast regeneration. Three cultivars (Romanian hybrids) and one inbred line were
used for protoplast isolation from etiolated hypocotyls. Isolated protoplasts were embedded in alginate disks and cultured
in two plating densities, using two culture regimes as indicated by previous authors. Plating efficiency, callus development
and plant regeneration were evaluated as well as old callus histology. In cv. ‘Select’, the effects of 1:50 haemoglobin and
1 mM spermidine were assayed on asymmetric division and/or plating efficiency. Plant regeneration from hypocotyl protoplasts
was achieved for two cvs., ‘Florom 328’ and ‘Turbo’, with the former proving once more its totipotency. The best culture regime
proved to be as recommended by Krasnyanski and Menczel (1993), but the best density in the culture medium was the highest ever tested, 8 × 105 pp ml−1. Moreover, the histology of old green compact protoplast-derived callus revealed a very well organized structure suggesting
senescence. In the non-responsive cv. ‘Select’, haemoglobin was found to stimulate protoplast asymmetric division and the
development of heart-shaped embryo-like structures, while spermidine stimulated overall protoplast plating efficiency. 相似文献
17.
Nawrocki J 《Communications in agricultural and applied biological sciences》2007,72(4):819-824
Field experiments were carried out in the years 2005 and 2006 on carrot cv. 'Koral' and 'Perfekcja', and parsley cv. 'Berlinska' and 'Cukrowa'. Effectiveness of substances: Biochikol 020 PC (biologically active substances BAS--chitosan 20 g/dm3), Bioczos BR (extract of garlic 10 g/1 brick) and Biosept 33 SL (extract of grapefruit 33%) on seedling roots of carrot and parsley was studied. As the standard fungicide Zaprawa Funaben T (carbendazim 20% + tiuram 45%) was used. Roots of carrot and parsley were treated one of tested substances spring immediately before planting seedling roots. During vegetation period the growth of seedling shoots and setting of seeds, and their infestation by fungal and bacterial pathogens was noticed. Among substances used for spring dressing of carrot and also parsley seedling roots, the best efficacy exhibited Zaprawa Funaben T in both years of observation. The highest yield of carrot seeds had combination roots cv. 'Koral' and parsley seeds roots cvs 'Berlińska' and 'Cukrowa' dressed Zaprawa Funaben T. Effectiveness of biopreparates Biochikol and Biosept was lower in comparison with the standard fungicide, but their protective effect was significantly higher than in control. Bioczos had the lowest control efficacy. 相似文献
18.
Pistil induction by hormones from callus of <Emphasis Type="Italic">Oryza sativa</Emphasis> in vitro
This study describes the successful formation of floral organ pistil from the callus of pistil explants of Oryza sativa L. For induction of floral organs, different explants—including young embryo, lemma, palea and pistil—were used for callus induction with different combinations of N6-benzyladenine and 2,4-dichlorophenoxyacetic acid (2,4-D). High frequencies of callus formation from pistil and young embryo explants were achieved. Floral organs were induced after calli from pistils were transferred to medium containing both zeatin and 2,4-D. The morphological characteristics of the pistil-like organs are very similar to those formed in planta though with minor differences. Further histological study revealed that the in vitro pistil contains an ovule within its ovary. Furthermore, a pistil-specific gene, OsMADS3 used as a molecular marker for pistil identity, was expressed in the pistil-like organs as it was in pistils in the flower of the plant. 相似文献
19.
The effects of genotype, pollen or growth regulator-pretreatment of pistils, developmental stage of the ovule (embryo sac)
and culture media on induction of gynogenesis, and subsequent plantlet regeneration in vitro were assessed in interspecific
Gossypium barbadense × G. hirsutum cotton hybrids. Gynogenesis occurred in all genotypes used when the pistils had been pre-treated with pollen from Hibiscus cannabinus and ovaries were harvested 5 or 10 days after anthesis. The use of culture media, SH and MS, showed no significant differences
in responding ovules, embryogenic ovules or embryo germination frequency. Recovered progeny were characterized cytogenetically
and microscopically to help documenting their reproductive basis. Root tip chromosome counts of 17 plants established from
ovule culture revealed that chromosome numbers ranged from 27 to 44. Although the reproductive mechanisms need to be characterized
more extensively by cytological and molecular means, the observations suggest that gynogenesis in cotton involves some unusual
reproductive events. Aneuploids could be useful for functional genomic characterization of genome shock, deletion mapping,
and germplasm introgression. 相似文献
20.
M. A. McNeilage 《Sexual plant reproduction》1991,4(4):267-273
Summary Flower and fruit characters were measured in ten female, five male and five fruiting male selections of A. deliciosa var deliciosa (A. Chev) Liang and Ferguson. Flowers from female vines had functional pistils, which contained many ovules. Stamens appeared to be fully developed but produced only empty pollen grains. Flowers from male vines had functional stamens that produced high percentages of pollen grains with stainable cytoplasmic contents. Pistils did not contain ovules and were generally small with vestigial styles. Fruiting male vines had both staminate and bisexual flowers. Staminate flowers were similar to those found on strictly male vines. Bisexual flowers produced ovules and stainable pollen. Pistils were smaller than in pistillate flowers. Although the three flower sexes differed in style length, ovary dimensions and ovules per carpel, staminate and bisexual flowers were similar in number of flowers per inflorescence, stamen filament length, pollen stainability, inflorescence rachis length and carpel number, and differed from pistillate flowers in these characters. The three flower sexes had similar sepal and petal numbers. The fruit of fruiting males were considerably smaller than those of females. Low ovule number appears to be the major factor limiting fruit size in the fruiting males studied. Prospects for developing hermaphroditic kiwifruit cultivars through breeding are discussed. 相似文献