共查询到20条相似文献,搜索用时 0 毫秒
1.
Mindaugas Grikpėdis Giedrė Motuzaitė Matuzevičiūtė 《Vegetation History and Archaeobotany》2016,25(6):601-610
In this paper we review the earliest Secale (rye) records, both pollen and macroremains, from the eastern Baltic region (northeast Poland, Lithuania, Latvia, Estonia and Finland) in order to understand the processes evident in the beginnings of rye cultivation. By taking note of the abundance of recovered Secale grains and pollen in relation to other cereals found in published archaeobotanical data, we try to understand when rye began to be used regionally as a staple food. The clarification of the timing of Secale in the East Baltic, that had social and economic implications, is of particular importance. In this publication we also present a radiocarbon date directly derived from dating a Secale grain from a Roman period hillfort in Lithuania. The date obtained constitutes the earliest record of Secale in the eastern Baltic region, showing that rye cultivation traditions and concomitant innovations in agricultural technology started there much earlier than previously suggested. 相似文献
2.
Alicja Szatanik-Kloc Patrycja Warchulska Grzegorz Józefaciuk 《Acta Physiologiae Plantarum》2009,31(1):59-64
The plants of winter rye variety Rostockie grown in nutrient solution prepared according to Marschner and Romheld (1983) were stressed at shooting stage with different zinc (ZnCl2) concentrations of 0, 20, 200 and 400 mgXdm−3 during 10 days at pH = 4.5. The control plants were grown continuously at pH = 7, without Zn2+. The roots of all plants were titrated with 0.1 molXdm−3 NaOH in 1 molXdm−3 NaCl solution with a rate 0.01 ml/min using auto-titrator Titrino 702 (Metrohm). The amount of the base consumed between
pH 3 and 10 was recorded with a step of 0.1 pH unit. From the titration data root surface charge was characterized. Roots
grown at pH = 4.5 without Zn2+ addition, had apparently the same charge properties as the control roots. Under 200 and 400 mgXdm−3 of zinc addition, variable charge, Q, and the cation exchange capacity, CEC, of the roots significantly decreased as did the fractions of surface acidic functional
groups of strong and medium acidity i.e. the groups having apparent surface dissociation constants, Kapp, between 10−3.5 and 10−5.5. For 20 mgXdm−3 zinc stress the fraction of weaker surface groups (surface dissociation constants around 10−6.5) decreased also. The surface charge density, SCD, of roots decreased under the Zn stress. 相似文献
3.
Monika Rakoczy-Trojanowska Wacław Orczyk Paweł Krajewski Jan Bocianowski Anna Stochmal Mariusz Kowalczyk 《Journal of applied genetics》2017,58(1):1-9
Hydroxamates (HX) are major secondary metabolites synthesized by rye and are responsible for some of the unique properties of this cereal, including good tolerance of biotic and abiotic stresses and allelopathy. Recently, five genes encoding enzymes taking part in HX biosynthesis have been sequenced and characterized, which was the starting point to undertake the present study. Association analysis of the content of six HX–HBOA (2-hydroxy-1,4-benzoxazin-3-one), GDIBOA (2,4-dihydroxy-1,4-benzoxazin-3(4H)-one glucoside), DIBOA (2,4-dihydroxy-1,4-benzoxazin-3(4H)-one), GDIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3(4H)-one glucoside), DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3(4H)-one) and MBOA (6-methoxy-benzoxazolin-2(3H)-one) in the above-ground parts of plants and roots was performed on a population consisting of 102 and 121 diverse inbred lines, in 2013 and 2014, respectively. Altogether, 48 single nucleotide polymorphisms (SNPs) were found to be associated with the content of at least one HX: 20 SNPs were associated with HX synthesized in the above-ground parts of rye plants (AG-SNP), and 28 were associated with HX synthesized in the roots (R-SNP). The highest number of SNPs was present in genes ScBx1 (9) and ScBx5 (11). The majority of SNPs were affected by environmental factors, except for two: ScBx4_1702 associated with GDIBOA and MBOA contents, and ScBx5_1105 associated with HBOA content in roots. 相似文献
4.
Grain quality of rye is often negatively affected by sprouting - a complex trait with a poorly understood genetic background and strong interaction with weather conditions. The aim of this report was to detect the main quantitative trait loci (QTLs) underlying preharvest sprouting resistance in rye, measured as a percentage of sprouted kernels after spraying spikes with water for 7 days. Simple and composite interval mapping, carried out in 3 environments on 94 F3 and F4 families of the cross between sprouting-susceptible (541) and sprouting-resistant (Ot1-3) inbred lines, revealed 5 QTLs located on chromosome arms 1RL, 2RL, 5RL, 6RL and 7RL. The significance of these QTLs was additionally proved by disruptive selection carried out on 5000 F2 plants of the 541 x Ot1-3 cross and continued to the F5 generation of recombinant inbred lines (RIL), which strongly affected allele frequencies at linked marker loci. Resistance to preharvest sprouting showed dominant inheritance except for QPhs.uas-7R.1 (recessive) and QPhs.uas-1R.1 (additive). Results of the present study suggest that introgression of 4-5 QTLs, identified in line Ot1-3, should substantially reduce sprouting risk in rye varieties. 相似文献
5.
Bolibok H Gruszczyńska A Hromada-Judycka A Rakoczy-Trojanowska M 《Cellular & molecular biology letters》2007,12(4):523-535
This study was conducted in order to identify quantitative trait loci (QTLs) for the in vitro culture response of winter rye (Secale cereale L.) immature embryos and immature inflorescences. A genetic linkage map comprising 67 SSRs, 9 ISSRs, 13 SAMPLs, 7 RAPDs,
2 SCARs and one EST marker was created based on the analyses of 102 recombinant inbred lines from the cross between lines
L318 (which has a good response in tissue cultures) and L9 (which is unable to regenerate plants from somatic tissues and
anthers). The map spans 979.2 cM, and the average distance between markers is 9.9 cM. Two characteristics were evaluated:
callus induction (CI) and somatic embryogenesis ability (SE). They were expressed as the percentage of immature embryos/inflorescences
producing callus (designated ECI/ICI) and the percentage of explants producing somatic embryos (ESE/ISE). All the analysed
traits showed continuous variation in the mapping population but a non-normal frequency distribution. We identified nine putative
QTLs controlling the tissue culture response of rye, explaining up to 41.6% of the total phenotypic variation: two QTLs for
ECI — eci-1, eci-2; 4 for ESE — ece-1, ese-2, ese-3, ese-4; 2 for ICI — ici-1, ici2; and 1 for ISE — ise-1. They were detected on chromosomes 1R, 4R, 5R, 6R and 7R. 相似文献
6.
S. V. Golubtsov S. P. Sosnikhina I. V. Iordanskaya A. V. Voilokov E. I. Mikhailova O. L. Kolomiets Yu. F. Bogdanov 《Russian Journal of Genetics》2010,46(6):682-688
A study was made of the expression and inheritance of the sy11 mutation, which alters homologous chromosome synapsis in meiotic prophase I of rye. The abnormal phenotype proved to be determined
by a recessive allele of a single sy11 gene. Univalents and multivalents were observed in homozygotes for the mutant allele. Analysis of the synaptonemal complex
revealed a combination of homologous and nonhomologous synapsis in the mutant. The nonhomologous synapsis frequency significantly
decreased in the course of meiotic prophase I in the mutant. The number of chiasmata per bivalent in metaphase I was 1.1 ±
0.01 versus 1.8 ± 0.01 in wild-type plants, and the number of univalents was 2.7 ± 0.06 versus 0.5 ± 0.05 in wild-type plants.
As a result, a broad range of abnormalities was observed at subsequent stages of meiosis and led to the formation of defective
microspores. Mutant plants were semisterile. 相似文献
7.
Bernd Hackauf Eva Bauer Viktor Korzun Thomas Miedaner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(6):1179-1189
Key message
A comparative genetics approach allowed to precisely determine the map position of the restorer gene Rfp3 in rye and revealed that Rfp3 and the restorer gene Rfm1 in barley reside at different positions in a syntenic 4RL/6HS segment.Abstract
Cytoplasmic male sterility (CMS) is a reliable and striking genetic mechanism for hybrid seed production. Breeding of CMS-based hybrids in cereals requires the use of effective restorer genes as an indispensable pre-requisite. We report on the fine mapping of a restorer gene for the Pampa cytoplasm in winter rye that has been tapped from the Iranian primitive rye population Altevogt 14160. For this purpose, we have mapped 41 gene-derived markers to a 38.8 cM segment in the distal part of the long arm of chromosome 4R, which carries the restorer gene. Male fertility restoration was comprehensively analyzed in progenies of crosses between a male-sterile tester genotype and 21 recombinant as well as six non-recombinant BC4S2 lines. This approach allowed us to validate the position of this restorer gene, which we have designated Rfp3, on chromosome 4RL. Rfp3 was mapped within a 2.5 cM interval and cosegregated with the EST-derived marker c28385. The gene-derived conserved ortholog set (COS) markers enabled us to investigate the orthology of restorer genes originating from different genetic resources of rye as well as barley. The observed localization of Rfp3 and Rfm1 in a syntenic 4RL/6HS segment asks for further efforts towards cloning of both restorer genes as an option to study the mechanisms of male sterility and fertility restoration in cereals.8.
Raúl de la Puente Ana Isabel González María Luisa Ruiz Carlos Polanco 《In vitro cellular & developmental biology. Plant》2008,44(5):419-426
Amplified fragment length polymorphism (AFLP) analysis of 24 in vitro regenerated rye plants was performed in order to evaluate the somaclonal variation rate in this species and to identify rye
genomic regions where mutations are preferentially promoted by in vitro culture processes. Regenerated plants were obtained from cell lines derived from immature embryos and plants were regenerated
by somatic embryogenesis. Twenty-three regenerants showed variation when compared against sibling plants obtained from the
same cell line. A total number of 887 AFLP markers were scored, and 8.8% identified the same polymorphism in plants obtained
independently from different cell lines, revealing putative mutational hot spots. Using controlled crossings and analysis
of the corresponding progenies, we were able to verify the genetic stability in the next generation for only five of these
polymorphisms. The nucleotide sequence of the AFLP amplicon of four of the polymorphic markers was obtained, but only the
sequence of two markers was clearly identified in the databases. The sequence of marker A1-303 was identified as part of a
tandemly repeated sequence, the 120-bp family, which is located at telomeric regions and is widely distributed among rye chromosomes.
The marker A5-375 showed high similarity with regions of Angela retrotransposons. 相似文献
9.
Roux SR Hackauf B Linz A Ruge B Klocke B Wehling P 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,110(1):202-201
Three dominant resistance genes, Pr3, Pr4, and Pr5, were identified by genetic analysis of resistance to leaf rust in rye (Puccinia recondita f. sp. secalis). Each of the three genes confers resistance to a broad scale of single-pustule isolates (SPIs), but differences could be observed for specific Pr gene/SPI combinations. Resistance conferred by the three genes was effective in both detached-leaf tests carried out on seedlings and in field tests of adult plants. Molecular marker analysis mapped Pr3 to the centromeric region of rye chromosome arm 1RS, whereas Pr4 and Pr5 were assigned to the centromeric region of 1RL. Chromosomal localization and reaction patterns to specific SPIs provide evidence that the three Pr genes represent distinct and novel leaf-rust resistance genes in rye. The contributions of these genes to resistance breeding in rye and wheat are discussed.The authors dedicate this paper to Prof. Dr. H.H. Geiger, University of Hohenheim, on the occasion of his 65th birthday.An erratum to this article can be found at 相似文献
10.
Grattapaglia D Ribeiro VJ Rezende GD 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(1):192-199
The conventional way to drive modifications in old forest tree seed orchards is to establish progeny trials involving each parent tree and then evaluate its contribution to the performance of the progeny by estimating its general and specific combining ability (GCA and SCA). In this work, we successfully applied an alternative parent selection tactic based on paternity testing of superior offspring derived from a hybrid seed orchard established with a single Eucalyptus grandis seed parents and six E. urophylla pollen parents. A battery of 14 microsatellite markers was used to carry out parentage tests of 256 progeny individuals including two independent samples of selected trees and one control unselected sample, all derived from 6-year-old forest stands in eastern Brazil. Paternity determination was carried out for all progeny individuals by a sequential paternity exclusion procedure. Exclusion was declared only when the obligatory paternal allele in the progeny tree was not present in the alleged parent tree for at least four independent markers to avoid false exclusions due to mutation or null alleles. After maternity checks to identify seed mixtures and selfed individuals, the paternity tests revealed that approximately 29% of the offspring was sired by pollen parents outside the orchard. No selfed progeny were found in the selected samples. Three pollen parents were found to have sired essentially all of the offspring in the samples of selected and non-selected progeny individuals. One of these three parents sired significantly more selected progeny than unselected ones (P0.0002 in a Fisher exact test). Based on these results, low-reproductive-successful parents were culled from the orchard, and management procedures were adopted to minimize external pollen contamination. A significant difference (P<0.01) in mean annual increment was observed between forest stands produced with seed from the orchard before and after selection of parents and revitalization of the orchard. An average realized gain of 24.3% in volume growth was obtained from the selection of parents as measured in forest stands at age 2–4 years. The marker-assisted tree-breeding tactic presented herein efficiently identified top parents in a seed orchard and resulted in an improved seed variety. It should be applicable for rapidly improving the output quality of seed orchards, especially when an emergency demand for improved seed is faced by the breeder.Communicated by D.B. Neale 相似文献
11.
B.-J. Shi J. P. Gustafson J. Button J. Miyazaki M. Pallotta N. Gustafson H. Zhou P. Langridge N. C. Collins 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(4):695-704
Rye is a diploid crop species with many outstanding qualities, and is important as a source of new traits for wheat and triticale
improvement. Rye is highly tolerant of aluminum (Al) toxicity, and possesses a complex structure at the Alt4 Al tolerance locus not found at the corresponding locus in wheat. Here we describe a BAC library of rye cv. Blanco, representing
a valuable resource for rye molecular genetic studies, and assess the library’s suitability for investigating Al tolerance
genes. The library provides 6 × genome coverage of the 8.1 Gb rye genome, has an average insert size of 131 kb, and contains
only ~2% of empty or organelle-derived clones. Genetic analysis attributed the Al tolerance of Blanco to the Alt4 locus on the short arm of chromosome 7R, and revealed the presence of multiple allelic variants (haplotypes) of the Alt4 locus in the BAC library. BAC clones containing ALMT1 gene clusters from several Alt4 haplotypes were identified, and will provide useful starting points for exploring the basis for the structural variability
and functional specialization of ALMT1 genes at this locus.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
12.
Chebotar S Röder MS Korzun V Saal B Weber WE Börner A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(8):1469-1476
The genetic integrity of six accessions represented by 14 sub-populations of the open-pollinating species rye (Secale cereale L.) was investigated. Seeds available from a herbarium collection (first regeneration) and from the cold store (most recent regeneration) were multiplied two to fourteen times and fingerprinted using microsatellite markers. Four accessions had significantly different allele frequencies. These were multiplied seven to thirteen times. Nearly 50% of the alleles discovered in the original samples were not found in the material present in the cold store. However alleles were detected in the most recently propagated sub-populations, that were not observed in the investigated plants of the original one. The change in allele frequencies is a continuous process. Reasons for the occurrence of genetic changes and consequences for managing open pollinating species maintained in ex situ genebanks are discussed.Communicated by G. Wenzel 相似文献
13.
A method for somatic embryogenesis and fertile green plant regeneration from suspension cell-derived protoplasts of rye (Secale cereale L. cv. Auvinen) was developed. Fast-growing and friable embryogenic calli with a high regeneration capacity were induced from immature rye inflorescences using modified MS medium. These friable embryogenic calli were used for suspension culture initiation in liquid AA medium. A high yield of protoplasts was obtained from suspension cell clumps after 3–5 days of subculture. Isolated protoplasts were cultured in KM8p medium. The frequency of protoplast cell divisions and colony formations in liquid culture medium were similar to those on agarose-solidified medium. Compact embryogenic calli were developed from protoplast-derived microcalli in growth medium mMS. Approximately 7% of the transferred embryogenic calli produced green shoots on N6 regeneration medium. Of 33 green plants, 28 were fertile with normal flowering and seed set. The ratio of green and albino plantlets was 1:4. Rye protoplast-derived green plants showed normal diploid characters as determined by flow cytometer analysis and chromosome counting.Abbreviations 2,4-D 2,4-Dichorophenoxyacetic acid - FDA Fluorescein diacetate - FW Fresh weight - GA3 Gibberellic acid - Kinetin 6-Furfurylaminopurine - IAA Indole-3-acetic acid - NAA -Naphthaleneacetic acid 相似文献
14.
S. P. Sosnikhina E. I. Mikhailova O. A. Tikholiz S. N. Priyatkina V. G. Smirnov A. V. Voilokov Yu. S. Fedotova O. L. Kolomiets Yu. F. Bogdanov 《Russian Journal of Genetics》2005,41(10):1071-1080
Genetic collection of meiotic mutants of winter rye Secale cereale L. (2n = 14) was created. Mutations were detected in inbred F2 generations after self-fertilization of the F1 hybrids, obtained by individual crossing of rye plants (cultivar Vyatka) or weedy rye with plants from autofertile lines. The mutations cause partial or complete plant sterility and are maintained in collection in a heterozygous state. Genetic analysis accompanied by cytogenetic study of meiosis has revealed six mutation types. (1) Nonallelic asynaptic mutations sy1 and sy9 caused the formation of only axial chromosome elements in prophase and anaphase. The synaptonemal complexes (SCs) were absent, the formation of the chromosome “bouquet” was impaired, and all chromosomes were univalent in meiotic metaphase I in 96.8% (sy1) and 67% (sy2) of cells. (2) Weak asynaptic mutation sy3, which hindered complete termination of synapsis in prophase I. Subterminal asynaptic segments were always observed in the SC, and at least one pair of univalents was present in metaphase I, but the number of cells with 14 univalents did not exceed 2%. (3) Mutations sy2, sy6, sy7, sy8, sy10, and sy19, which caused partially nonhomologous synapsis: change in pairing partners and fold-back chromosome synapsis in prophase I. In metaphase I, the number of univalents varied and multivalents were observed. (4) Mutation mei6, which causes the formation of ultrastructural protrusions on the lateral SC elements, gaps and branching of these elements. (5) Allelic mutations mei8 and mei8-10, which caused irregular chromatin condensation along chromosomes in prophase I, sticking and fragmentation of chromosomes in metaphase I. (6) Allelic mutations mei5 and mei10, which caused chromosome hypercondensation, defects of the division spindle formation, and random arrest of cells at different meiotic stages. However, these mutations did not affect the formation of microspore envelopes even around the cells, whose development was blocked at prophase I. Analysis of cytological pictures of meiosis in double rye mutants reveled epistatic interaction in the mutation series sy9 > sy1 > sy3 > sy19, which reflects the order of switching these genes in the course of meiosis. The expression of genes sy2 and sy19 was shown to be controlled by modifier genes. Most meiotic mutations found in rye have analogs in other plant species. 相似文献
15.
M. Targońska H. Bolibok-Brągoszewska M. Rakoczy-Trojanowska 《Plant Molecular Biology Reporter》2016,34(1):37-51
The primary aim of this study was to estimate genetic diversity among Secale cereale L. accessions using 22 previously published simple sequence repeat (SSR) markers. The plant material included 367 rye accessions comprising historical and contemporary cultivars, cultivated materials, landraces, and breeding strains from the Polish breeding company Danko. The studied accessions represented a wide geographical diversity. Several methods were employed to analyze genetic diversity among the Secale cereale L. accessions and to determine population structure: principal coordinate analysis (PCoA), neighbor-joining (NJ), and Bayesian clustering. We also defined a core collection of 25 rye accessions representing over 93 % of SSR alleles. The results of these analyses showed that accessions from the rye gene bank are clearly divergent in comparison with materials received directly from European breeding companies. Our findings suggest also that the genetic pool of current rye cultivars is becoming narrower during breeding processes. The selected panel of SSR markers performed well in detection of genetic diversity patterns and can be recommended for future germplasm characterization studies in rye. 相似文献
16.
Wehling P Linz A Hackauf B Roux SR Ruge B Klocke B 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(3):432-438
Genetic analysis of resistance to leaf rust in rye (Puccinia recondita f. sp. secalis) led to the identification of two dominant resistance genes, Pr1 and Pr2. Both genes proved to be effective against a local leaf-rust population as well as a subset of single-pustule isolates (SPIs) the latter of which comprised SPIs with very high virulence complexity. Resistance conferred by Pr1 and Pr2 was expressed in detached-leaf tests of seedlings as well as in field tests of adult plants. Molecular marker analysis allowed us to map Pr1 in the proximal part of rye chromosome 6RL, whereas Pr2 was assigned to the distal part of chromosome 7RL. These results are discussed in view of homoeology relationships among Triticeae. A proposal is submitted for the designation of resistance genes to rye leaf rust which would avoid interference with existing gene-symboling in respect to wheat leaf-rust resistances introgressed from rye into wheat or triticale. 相似文献
17.
Camacho MV Matos M González C Pérez-Flores V Pernaute B Pinto-Carnide O Benito C 《Genetica》2005,123(3):303-311
The polymerase chain reaction (PCR) was used to locate Secale cereale (inter-simple sequence repeat ISSR) or Secale cereale inter-microsatellite (SCIM) markers using wheat–rye addition lines in order to develop a set of molecular markers distributed on the seven rye chromosomes. The number of SCIM markers located on 1R, 2R, 3R, 4R, 5R, 6R and 7R chromosomes were 4, 3, 12, 3, 2, 9 and 8, respectively. Therefore, a total of 41 new SCIMs were located on the seven rye chromosomes. The segregation of the 63 different SCIM markers in three different F2 was studied. The observed ISSR segregations were the 3:1 (50.7%), the 15:1 (12.7%) and the 1:1 (14.2%). The linkage analysis carried out indicated that seven of the segregating SCIMs were linked to chromosome 7R and two were linked to chromosome 4R. The use of the SCIM markers as a source of molecular markers that could be linked to interesting genes or other important agronomic traits is discussed. 相似文献
18.
19.
Mirdita V Dhillon BS Geiger HH Miedaner T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,118(1):85-90
Ergot (Claviceps purpurea [Fr.] Tul.) is a serious disease of rye (Secale cereale L.) and it adversely affects the quality of grain. The present investigation was undertaken to study genotypic variability among
full-sib families (FSF) of five open-pollinated (OP) winter rye populations of highly diverse origin, namely Dankovskie Selekcyine
(Poland), Charkovskaja (Ukraine), NEM4 (Russia), Halo and Carokurz, both from Germany. About 50 FSF were developed at random
in each population, and the FSF of each population were evaluated in separate but adjacent experiments conducted in four environments
under artificial inoculation. A mixture of conidia of C. purpurea isolates was sprayed thrice during the flowering period. The materials were manually harvested at yellow-ripe stage. Resistance
trait recorded was disease severity, i.e. percent ergot sclerotia in grain by weight. Mean ergot severity ranged from 2.29
to 4.08% for the five populations across environments. Significant genotypic variation (P < 0.01) due to FSF and FSF × environment interaction was observed within each population. Genotypic variation within all
populations was higher than that among five populations. All populations showed high estimates of heritability (0.72–0.89).
The study indicated that the evaluated OP populations are rich reservoirs of genetic variation that should also be used in
hybrid breeding. Recurrent selection to further improve ergot resistance should be successful. 相似文献
20.
Hamid Rismani-Yazdi Kristin H. Hampel Christopher D. Lane Ben A. Kessler Nicholas M. White Kenneth M. Moats F. C. Thomas Allnutt 《Bioprocess and biosystems engineering》2015,38(4):639-650
A mixed trophic state production process for algal lipids for use as feedstock for renewable biofuel production was developed and deployed at subpilot scale using a green microalga, Auxenochlorella (Chlorella) protothecoides. The process is composed of two separate stages: (1) the photoautotrophic stage, focused on biomass production in open ponds, and (2) the heterotrophic stage focused on lipid production and accumulation in aerobic bioreactors using fixed carbon substrates (e.g., sugar). The process achieved biomass and lipid productivities of 0.5 and 0.27 g/L/h that were, respectively, over 250 and 670 times higher than those obtained from the photoautotrophic cultivation stage. The biomass oil content (over 60 % w/DCW) following the two-stage process was predominantly monounsaturated fatty acids (~82 %) and largely free of contaminating pigments that is more suitable for biodiesel production than photosynthetically generated lipid. Similar process performances were obtained using cassava hydrolysate as an alternative feedstock to glucose. 相似文献