Improvement of maturation and conversion of horse chestnut androgenic embryos

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Ćalić-Dragosavac, D.

2010-12-01

Full Text Available Horse chestnut (Aesculus hippocastanum L., Hippocastanaceae is a relict species of the tertiary flora and endemit of Balkan peninsula. It has enormous horticultular and medical important. Horse chestnut trees are native to the Balkan peninsula, but grow as ornamental trees in parks and avenues throughout the Northern Hemisphere. Because of the slow and difficult reproduction of great importance to be fast and cheap in vitro multiplication. Possible solution is regenerated by androgenesis. Microspore culture has been used in recent years as a tool for producing haploid plants in a varyety of higher plants, but the low frequencies of microspore-derived plants restrict the use of the technique in plant breeding.

Effects of free and chelated iron on in vitro androgenesis in barley and wheat

Czech Academy of Sciences Publication Activity Database

Novotný, J.; Vagera, Jiří; Ohnoutková, Ludmila

2000-01-01

Roč. 63, - (2000), s. 35-40 ISSN 0167-6857 R&D Projects: GA ČR GV521/96/K117 Institutional research plan: CEZ:AV0Z5038910 Keywords : ferrous ions * Hordeum vulgare * Triticum aestivum Subject RIV: EF - Botanics Impact factor: 0.444, year: 2000

Reduction of ploidy level by androgenesis in intergeneric Lolium-Festuca hybrids for turf grass breeding

Czech Academy of Sciences Publication Activity Database

Kopecký, David; Lukaszewski, A.J.; Gibeault, V.

2005-01-01

Roč. 45, č. 1 (2005), s. 274-281 ISSN 0011-183X Institutional research plan: CEZ:AV0Z50380511 Keywords : anther culture * pentaploid hybrids * perenne L. Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.925, year: 2005

Tissue culture-induced genetic and epigenetic variation in triticale (× Triticosecale spp. Wittmack ex A. Camus 1927) regenerants.

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Machczyńska, Joanna; Zimny, Janusz; Bednarek, Piotr Tomasz

2015-10-01

Plant regeneration via in vitro culture can induce genetic and epigenetic variation; however, the extent of such changes in triticale is not yet understood. In the present study, metAFLP, a variation of methylation-sensitive amplified fragment length polymorphism analysis, was used to investigate tissue culture-induced variation in triticale regenerants derived from four distinct genotypes using androgenesis and somatic embryogenesis. The metAFLP technique enabled identification of both sequence and DNA methylation pattern changes in a single experiment. Moreover, it was possible to quantify subtle effects such as sequence variation, demethylation, and de novo methylation, which affected 19, 5.5, 4.5% of sites, respectively. Comparison of variation in different genotypes and with different in vitro regeneration approaches demonstrated that both the culture technique and genetic background of donor plants affected tissue culture-induced variation. The results showed that the metAFLP approach could be used for quantification of tissue culture-induced variation and provided direct evidence that in vitro plant regeneration could cause genetic and epigenetic variation.

Selective deletion of Pten in theca-interstitial cells leads to androgen excess and ovarian dysfunction in mice.

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Lan, Zi-Jian; Krause, M S; Redding, S D; Li, X; Wu, G Z; Zhou, H X; Bohler, H C; Ko, C; Cooney, A J; Zhou, Junmei; Lei, Z M

2017-03-15

Theca cell-selective Pten mutation (tPtenMT) in mice resulted in increases in PDK1 and Akt phosphorylation, indicating an over-activation of PI3K signaling in the ovaries. These mice displayed elevated androgen levels, ovary enlargement, antral follicle accumulation, early fertility loss and increased expression of Lhcgr and genes that are crucial to androgenesis. These abnormalities were partially reversed by treatments of PI3K or Akt inhibitor. LH actions in Pten deficient theca cells were potentiated. The phosphorylation of Foxo1 was increased, while the binding of Foxo1 to forkhead response elements in the Lhcgr promoter was reduced in tPtenMT theca cells, implying a mechanism by which PI3K/Akt-induced upregulation of Lhcgr in theca cells might be mediated by reducing the inhibitory effect of Foxo1 on the Lhcgr promoter. The phenotype of tPtenMT females is reminiscent of human PCOS and suggests that dysregulated PI3K cascade in theca cells may be involved in certain types of PCOS pathogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

The Chromosomal Constitution of Embryos Arising from Monopronuclear Oocytes in Programmes of Assisted Reproduction

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Bernd Rosenbusch

2014-01-01

Full Text Available The assessment of oocytes showing only one pronucleus during assisted reproduction is associated with uncertainty. A compilation of data on the genetic constitution of different developmental stages shows that affected oocytes are able to develop into haploid, diploid, and mosaic embryos with more or less complex chromosomal compositions. In the majority of cases (~80%, haploidy appears to be caused by gynogenesis, whereas parthenogenesis or androgenesis is less common. Most of the diploid embryos result from a fertilization event involving asynchronous formation of the two pronuclei or pronuclear fusion at a very early stage. Uniparental diploidy may sometimes occur if one pronucleus fails to develop and the other pronucleus already contains a diploid genome or alternatively a haploid genome undergoes endoreduplication. In general, the chance of obtaining a biparental diploid embryo appears higher after conventional in vitro fertilization than after intracytoplasmic sperm injection. If a transfer of embryos obtained from monopronuclear oocytes is envisaged, it should be tried to culture them up to the blastocyst since most haploid embryos are not able to reach this stage. Comprehensive counselling of patients on potential risks is advisable before transfer and a preimplantation genetic diagnosis could be offered if available.

Hybridogenesis and a potential case of R2 non-LTR retrotransposon horizontal transmission in Bacillus stick insects (Insecta Phasmida).

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Scavariello, Claudia; Luchetti, Andrea; Martoni, Francesco; Bonandin, Livia; Mantovani, Barbara

2017-02-06

Horizontal transfer (HT) is an event in which the genetic material is transferred from one species to another, even if distantly related, and it has been demonstrated as a possible essential part of the lifecycle of transposable elements (TEs). However, previous studies on the non-LTR R2 retrotransposon, a metazoan-wide distributed element, indicated its vertical transmission since the Radiata-Bilateria split. Here we present the first possible instances of R2 HT in stick insects of the genus Bacillus (Phasmida). Six R2 elements were characterized in the strictly bisexual subspecies B. grandii grandii, B. grandii benazzii and B. grandii maretimi and in the obligatory parthenogenetic taxon B. atticus. These elements were compared with those previously retrieved in the facultative parthenogenetic species B. rossius. Phylogenetic inconsistencies between element and host taxa, and age versus divergence analyses agree and support at least two HT events. These HT events can be explained by taking into consideration the complex Bacillus reproductive biology, which includes also hybridogenesis, gynogenesis and androgenesis. Through these non-canonical reproductive modes, R2 elements may have been transferred between Bacillus genomes. Our data suggest, therefore, a possible role of hybridization for TEs survival and the consequent reshaping of involved genomes.

In vitro haploid zygotic embryogenesis due to pollination with maize pollen and induced in vitro androgenesis in Czech wheat breeding genotypes

Czech Academy of Sciences Publication Activity Database

Vagera, Jiří; Nesvadba, Z.; Martinek, P.; Ohnoutková, Ludmila

2001-01-01

Roč. 47, č. 5 (2001), s. 193-200 ISSN 0370-663X R&D Projects: GA ČR GA521/01/1383; GA ČR GV521/96/K117 Institutional research plan: CEZ:AV0Z5038910 Keywords : haploid zygote * embryogenesis * maize pollen Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.237, year: 2001

Female Mimicry by Sneaker Males Has a Transcriptomic Signature in Both the Brain and the Gonad in a Sex-Changing Fish.

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Todd, Erica V; Liu, Hui; Lamm, Melissa S; Thomas, Jodi T; Rutherford, Kim; Thompson, Kelly C; Godwin, John R; Gemmell, Neil J

2018-01-01

Phenotypic plasticity represents an elegant adaptive response of individuals to a change in their environment. Bluehead wrasses (Thalassoma bifasciatum) exhibit astonishing sexual plasticity, including female-to-male sex change and discrete male morphs that differ strikingly in behavior, morphology, and gonadal investment. Using RNA-seq transcriptome profiling, we examined the genes and physiological pathways underlying flexible behavioral and gonadal differences among female, dominant (bourgeois) male, and female-mimic (sneaker) male blueheads. For the first time in any organism, we find that female mimicry by sneaker males has a transcriptional signature in both the brain and the gonad. Sneaker males shared striking similarity in neural gene expression with females, supporting the idea that males with alternative reproductive phenotypes have "female-like brains." Sneaker males also overexpressed neuroplasticity genes, suggesting that their opportunistic reproductive strategy requires a heightened capacity for neuroplasticity. Bourgeois males overexpressed genes associated with socio-sexual behaviors (e.g., isotocin), but also neuroprotective genes and biomarkers of oxidative stress and aging, indicating a hitherto unexplored cost to these males of attaining the reproductively privileged position at the top of the social hierarchy. Our novel comparison of testicular transcriptomes in a fish with male sexual polymorphism associates greater gonadal investment by sneaker males with overexpression of genes involved in cell proliferation and sperm quality control. We propose that morphological female-mimicry by sneaker male teleosts entails pervasive downregulation of androgenesis genes, consistent with low androgen production in males lacking well-developed secondary sexual characters. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Induction of gynogenetic and androgenetic haploid and doubled haploid development in the brown trout (Salmo trutta Linnaeus 1758).

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Michalik, O; Dobosz, S; Zalewski, T; Sapota, M; Ocalewicz, K

2015-04-01

Gynogenetic and androgenetic brown trout (Salmo trutta Linnaeus 1758) haploids (Hs) and doubled haploids (DHs) were produced in the present research. Haploid development was induced by radiation-induced genetic inactivation of spermatozoa (gynogenesis) or eggs (androgenesis) before insemination. To provide DHs, gynogenetic and androgenetic haploid zygotes were subjected to the high pressure shock to suppress the first mitotic cleavage. Among haploids, gynogenetic embryos were showing lower mortality when compared to the androgenetic embryos; however, most of them die before the first feeding stage. Gynogenetic doubled haploids provided in the course of the brown trout eggs activation performed by homologous and heterologous sperm (rainbow trout) were developing equally showing hatching rates of 14.76 ± 2.4% and 16.14 ± 2.90% and the survival rates at the first feeding stage of 10.48 ± 3.48% and 12.78 ± 2.18%, respectively. Significantly, lower survival rate was observed among androgenetic progenies from the diploid groups with only few specimens that survived to the first feeding stage. Cytogenetic survey showed that among embryos from the diploid variants of the research, only gynogenetic individuals possessed doubled sets of chromosomes. Thus, it is reasonable to assume that radiation employed for the genetic inactivation of the brown trout eggs misaligned mechanism responsible for the cell divisions and might have delayed or even arrested the first mitotic cleavage in the androgenetic brown trout zygotes. Moreover, protocol for the radiation-induced inactivation of the paternal and maternal genome should be adjusted as some of the cytogenetically surveyed gynogenetic and androgenetic embryos exhibited fragments of the irradiated chromosomes. © 2015 Blackwell Verlag GmbH.

Comparative morphology, biology and histology of reproductive development in three lines of Manihot esculenta Crantz (Euphorbiaceae: Crotonoideae).

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Perera, P I P; Quintero, M; Dedicova, B; Kularatne, J D J S; Ceballos, H

2013-01-01

Cassava (Manihot esculenta), a major food staple in the tropics and subtropics, thrives even in environments undergoing threatening climate change. To satisfy the increasing demand for crop improvement and overcome the limitations of conventional breeding, the introduction of inbreeding techniques such as the production of doubled haploid lines via androgenesis or gynogenesis offers advantages. However, comprehensive studies on cassava flower bud biology or structural development are lacking and precise structural and biological information is a prerequisite to enhance the efficiency of these techniques. The floral biology of three selected cassava lines was studied, focusing on morphology, phenology and pollen biology (quantity, viability and dimorphism). Histological studies were also conducted on microsporogenesis/microgametogenesis and megasporogenesis/megagameto-genesis to generate precise developmental data for these lines. Male and female cyathia have distinct developmental phases. Pollen viability was high during immature stages of plant development; however, pollen mortality was common at later stages. Pollen trimorphism in male gametophytes towards the larger or smaller pollen size, as compared with normal size, was observed. Ten characteristic events were identified in male gametogenesis and six in female gametogenesis that were correlated with flower bud diameter. Male gametophyte diameter at different developmental stages was also determined. Results indicate that the three lines did not differ significantly, except regarding a few morphological aspects such as plant height, flower colour and number of male cyathia. Pollen grains were initially viable, but viability decreased drastically at later stages of growth. Abnormal meiosis or mitosis triggered pollen trimorphism. The demonstrated sequential events of reproductive development generated valuable information at the cellular level, which will help close the current information gap for cassava

Anti-androgen vinclozolin impairs sperm quality and steroidogenesis in goldfish.

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Hatef, Azadeh; Alavi, Sayyed Mohammad Hadi; Milla, Sylvain; Křišťan, Jiří; Golshan, Mahdi; Fontaine, Pascal; Linhart, Otomar

2012-10-15

In mammals, vinclozolin (VZ) is known as anti-androgen, which causes male infertility via androgen receptor (AR) antagonism. In aquatic animals, the VZ effects on reproductive functions are largely unknown and results are somewhat contradictory. To understand VZ adverse effects on male reproduction, mature goldfish (Carassius auratus) were exposed to three nominal VZ concentrations (100, 400, and 800 μg/L) and alternations in gonadosomatic (GSI) and hepatosomatic indices (HSI), 17β-estradiol (E(2)), 11-ketotestosterone (11-KT) and sperm quality were investigated compared to the solvent control. One group was exposed to E(2) (nominal concentration of 5 μg/L), an estrogenic compound, as a negative control. Following one month exposure, GSI and HSI were unchanged in all VZ treated groups compared to solvent control. Sperm volume, motility and velocity were reduced in fish exposed to 800 μg/L VZ. This was associated with the decrease in 11-KT level, suggesting direct VZ effects on testicular androgenesis and sperm functions. In goldfish exposed to 100 μg/L VZ, 11-KT was increased but E(2) remained unchanged. This is, probably, the main reason for unchanged sperm quality at 100 μg/L VZ. In goldfish exposed to E(2), GSI and 11-KT were decreased, E(2) was increased and no sperm was produced. The present study shows different dose-dependent VZ effects, which lead to impairment in sperm quality via disruption in steroidogenesis. In addition to VZ effects through competitive binding to AR, our data suggests potential effects of VZ by direct inhibition of 11-KT biosynthesis in fish as well as abnormalities in sperm morphology. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluation of chemical castration with calcium chloride versus surgical castration in donkeys: testosterone as an endpoint marker.

Science.gov (United States)

Ibrahim, Ahmed; Ali, Magda M; Abou-Khalil, Nasser S; Ali, Marwa F

2016-03-08

For the last few years, researchers have been interested in developing a method for chemical sterilization which may be a better alternative to surgical castration. An ideal chemical sterilant would be one that effectively arrests spermatogenesis and androgenesis as well as libido with absence of toxic or other side effects. Calcium chloride in various solutions and concentrations has been tested in many animal species, but few studies have been evaluated it in equines as a chemical sterilant. So, the objective of this study was to evaluate the clinical efficacy of chemical castration with 20% calcium chloride dissolved in absolute ethanol in comparison with surgical castration in donkeys based on the changes in the serum testosterone level and the histopathological changes in treated testes. Twelve clinically healthy adult male donkeys were used in this study. Donkeys were divided randomly and equally into two groups: a surgical (S) group (n = 6) and a chemical (C) group (n = 6). Animals in the (S) group were subjected to surgical castration while those in the (C) group received a single bilateral intratesticular injection of 20% calcium chloride dissolved in absolute ethanol (20 ml/testis). Animals were kept under clinical observation for 60 days. Changes in animals' behavior and gross changes in external genitalia were monitored daily. Serum concentrations of testosterone were measured prior to treatment and at 15, 30, 45 and 60 days post-treatment. Testicles in the (C) group were examined histopathologically at the end of the experiment. Chemical castration with intratesticular calcium chloride vs. surgical castration failed to reduce serum concentrations of testosterone throughout the whole duration of the study; however it induced orchitis that was evident by focal necrotic areas in seminiferous tubules, cellular infiltration of neutrophils, proliferative intertubular fibrosis with a compensatory proliferation of Leydig cells. Donkeys tolerated the

Morphological markers for microspore developmental stage in maize

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Ana Paula de Moraes

2008-10-01

Full Text Available The use of maize in anther culture has been limited because only few genotypes presented a high androgenetic potential. Obtaining the proper stage of microspore development at culture initiation is one of the most crucial factors for success in the androgenesis. For Brazilian maize genotypes there are no studies reporting a correlation between cytological features and morphological parameters. In this study, morphological parameters were recorded and associated with cytological specific stages of the the microsporogenesis in two Brazilian maize genotypes that were sowed in different places (field and growing chamber. For both genotypes, the plants of the growing chamber presented a delay in development. Spikelets length and anther length/spikelet length ratio are not good parameters since they can be greatly influenced by the environment. The anther length was the more reliable parameter to correlate with a specific developmental stage. Nevertheless, variations between genotypes and environment were detected.A utilização do milho (Zea mays na cultura de anteras é limitada devido ao baixo número de genótipos com alto potencial androgenético. A obtenção de micrósporos no estádio de desenvolvimento apropriado no início da cultura é um dos fatores cruciais para o sucesso do processo androgenético. Em genótipos brasileiros de milho não existem estudos relatando a correlação entre características citológicas e parâmetros morfológicos. Neste estudo, parâmetros morfológicos foram avaliados e associados com estádios específicos da microsporogênese em dois genótipos brasileiros de milho os quais foram semeados em diferentes locais (campo e câmara de crescimento. Para ambos os genótipos, as plantas crescidas na câmara de crescimento apresentaram atraso no desenvolvimento. O comprimento da espigueta e a razão comprimento da antera/comprimento da espigueta não são bons parâmetros uma vez que podem ser muito influenciados

Haplodiploid androgenetic breeding in oat: genotypic variation in anther size and microspore development stage Melhoramento por haplodiploidização androgenética: variação genotípica no tamanho das anteras e no estágio de desenvolvimento dos micrósporos em aveia

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Taniela De Cesaro

2009-02-01

Full Text Available Oat (Avena spp. is poorly responsive to the haplodiploidization process, which leads to the production of homozygous lines in one step, increasing breeding efficiency. Androgenetic haploids in small grain cereal crops are obtained from microspores cultured at the mononucleate stage, which can be identified by the size of anthers. In order to identify the appropriate anther size for in vitro culture, microspore cytological analyses were made in Avena sativa cultivars UPF 7, UPF 18, UFRGS 14, Stout and Avena sterilis CAV 3361, cultivated in growth chamber under controlled light and temperature conditions. Variation was observed within and among genotypes for anther size at each microspore developmental stage and according to the position of spikelets in the panicle. Architecture variation in panicle shape and non-linear microsporogenesis maturation increased the challenge of identifying potentially androgenetic oat anthers. Cytological screening before culture is critical in identifying microspores at the right stage for oat androgenesis.A aveia (Avena spp. tem sido pouco responsiva à haplodiploidização, um processo que aumenta a eficiência da seleção no melhoramento por gerar, em uma etapa, linhas puras homozigóticas. A fase mononucleada do micrósporo é critica para o sucesso da androgênese in vitro nos cereais de inverno e, em geral, pode ser inferida pelo tamanho da antera. Foram medidas anteras e analisados citológicamente micrósporos das cultivares de Avena sativa UPF 7, UPF 18, UFRGS 14, Stout e da linhagem CAV 3361 de Avena sterilis, cultivadas em câmaras de crescimento sob temperaturas dia-noite variando de 16ºC a 9ºC e 12 horas de intensidade luminosa de 300 mol m-2 s-1. O tamanho das anteras em cada fase de desenvolvimento dos micrósporos variou significativamente entre genótipos e de acordo com a região de inserção das espiguetas na panícula. A variação na arquitetura da panícula e a maturação não linear das

Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

International Nuclear Information System (INIS)

Karayuecel, I.

1999-05-01

The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6±3.5% (relative to controls) with optimal UV irradiation dose of 450JM -2 for 5 minutes. The highest survival rate of diploid androgens was 0.07±0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12±0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3±1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0±5.2 and 33.8±1.5% were produced, significantly higher intersex percentages of 18.5±2.5 and 1.6±0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62.6±9.8% compared to the

Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

Energy Technology Data Exchange (ETDEWEB)

Karayuecel, I

1999-05-01

The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6{+-}3.5% (relative to controls) with optimal UV irradiation dose of 450JM{sup -2} for 5 minutes. The highest survival rate of diploid androgens was 0.07{+-}0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12{+-}0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3{+-}1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0{+-}5.2 and 33.8{+-}1.5% were produced, significantly higher intersex percentages of 18.5{+-}2.5 and 1.6{+-}0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62

Genotypic differences in proembryoid development and green plantlets regeneration through androgenesis in barley varieties Diferenças genotípicas no desenvolvimento de pró-embrióides e regeneração de plântulas verdes via androgênese em genótipo de cevada

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Paula Wiethölter

2008-02-01

Full Text Available The development of in vitro haploid plants followed by spontaneous or induced genome duplication allows to achieve, in one generation, the recovery of total homozygosis. The efficiency of the haplodiploidization process through in vitro anther culture of barley is variable among genotypes. This study was aimed at determining the androgenetic response of nine barley genotypes from the breeding program of Embrapa Trigo, analysing proembryoid development and green plantlets regeneration in anthers cultivated in vitro. Cultivar 'BR2' presented the highest average of proembryoids (104/anther and 'MN698' presented the highest average of green plantlets (0,41/anther. There was a significant variation among the average values of barley genotypes for embryo formation and green plantlets regeneration, making possible the selection to combine androgenetic capacity and good agronomic traits.A obtenção, na cevada, de plantas haplóides in vitro e a posterior duplicação natural ou artificial do genoma permitem alcançar a homozigose completa, em uma geração. A eficiência da haplodiploidização pela cultura de anteras é variável entre os genótipos. Foi avaliada a resposta androgenética através da formação de pró-embrióides e da regeneração de plântulas verdes em nove cultivares do programa de melhoramento de cevada da Embrapa Trigo, em anteras cultivadas in vitro. A cultivar "BR2" apresentou maior média de pró-embrióides (104/antera, enquanto "MN698" mostrou a maior média de plântulas verdes (0,41/antera. Houve variação significativa entre os valores médios dos genótipos em relação à formação de pró-embrióides e à regeneração de plântulas verdes, indicando a possibilidade de seleção para combinar a capacidade androgenética com boas características agronômicas.