Comparison of Taste Components between Triploid and Diploid Oyster

The main taste components of triploid and diploid oyster (Crassostrea gigas) were compared. Free amino acids, inosine monophosphate, succinate, trimethylamine oxide and betaine in fresh and boiled extractives were analyzed. The protein, lipids, glycogen, moisture and ash, which may affect the flavour, were evaluated. In boiled extractives, the amino acids were 394.1 mg(100 g) -1 in diploid and 183.5 mg(100 g) -1 in triploid. However, in fresh oyster extractives, they were 320.0 mg(100 g) -1 and 147.3 mg(100 g) -1 respectively. The inosine monophosphate in triploid was 44% more than that in diploid, and a little difference existed in the content of trimethylamine oxide between them. The contents of these taste components were the basis for taste flavour pattern determination.

STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFT-EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S.)

The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fertilized eggs at 0-2℃ for 45 minutes duration 5 minutes after fertilization, and the induced triploidy rates were 31.2%-50% and the relative hatching rates were 53.3%-99%. Gynogenetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0-2℃ for 45 minutes duration 5 minutes after fertilization. The induced gynogenetic diploid rates and the relative hatching rates were 94%-96% and 48.5%-68.5% respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae according to Student’s t test (α=0.05). The relationship between the early growth of the triploid experimental group larvae and that of gynogenetic diploid experimental group larvae was also studied.

Seasonal Variation of the Glycogen Enzyme Activity in Diploid and Triploid Pacific Oyster Gonad During Sexual Maturation

The glycogen content and the activities of two key enzymes in glycogen metabolism, glycogen phosphorylase and gly- cogen synthetase, in the gonad of diploid and triploid Pacific oysters (Crassostrea gigas) were compared during maturation. The glycogen content in the gonad of diploids decreased with gametogenesis (by 85.7%), but the glycogen content in the gonad of trip- loids did not vary significantly. Activity of glycogen phosphorylase (GP) in the gonad of diploids decreased with gametogenesis (by 55.5%), while GP activity of triploids did not vary significantly during maturation. Activity of glycogen synthetase (GS) in the gonad of diploids increased slightly with gametogenesis, reaching a peak in June. Activity of GS declined sharply from June to July, which might be due to gonad spawning. GS activity of triploid oysters in spawning time (July and August) was significantly higher than that in other months, which might be explained with a ‘compensating’ mechanism for the higher glycogen content in triploids.

Analysis on Genetic Background of Female Triploid and Male Diploid Individuals of Siraitia grosvenorii by Using RAPD Molecular Markers

In order to provide molecular biological basis for breeding of excellent seedless varieties of Siraitia grosvenorii, the genetic background of 28 female triploid and male diploid individuals of S. grosvenorii was analyzed by using RAPD molecular markers. The results showed that female triploid and male diploid individuals of S. grosvenorli had abundant genetic background, with great genetic similarity cecfficients and close genetic distance. Overall, the genetic background of female triploid and male diploid individuals of S. grosvenorii exhibited relatively low complexity. Therefore, it is necessary to take corresponding measures for germplasm innovation to enrich the genetic background of seedless parents of S. grosvenorii.

Comparative Analysis of the Transcriptome and Metabolome in Leaves of Diploid and Tetraploid Fagopyrum tataricum

Tartary buckwheat(Fagopyrum tataricum)is a dual-purpose medicinal and food crop grown for its high contents of functional compounds and abundant nutrients.Although studies have shown the differences of total flavonoid content in Tartary buckwheat at different ploidy levels,the composition of flavonoid and its regulatory mechanisms are largely unknown.In this study,the leaf metabolome and transcriptome of diploid and tetraploid accessions of Tartary buckwheat were analyzed to gain insight into the impact of polyploidization on comparative secondary metabolite composition and molecular regulatory mechanism.Based on a widely targeted metabolomics analysis,a total of 792 metabolites were identified,including 127 flavonoids.The accumulation of 127 metabolites and expression of 3871 genes differed significantly between diploid and tetraploid Tartary buckwheat.Integrated metabolomics and transcriptome analysis revealed that chromosome doubling up-regulated the expression of upstream genes in the flavonoid biosynthesis pathway to promote the accumulation of flavonoids.The present results contribute to elucidation of the molecular mechanism of phenotypic variation associated with polyploidy in Tartary buckwheat.The findings provide a reference for further studies on phenotypic traits in polyploid Tartary buckwheat,the cloning of crucial regulatory genes,and utilization of genetic engineering technologies in the breeding of Tartary buckwheat.

Productive Traits and Triploid Rate Stability in Triploidy-Induced ‘Haida No. 2’ Strain of the Pacific Oyster, Crassostrea gigas

In order to evaluate the effects of triploidy induction on a selected strain‘Haida No.2’of the Pacific oyster Crassostrea gigas,which is characterized with golden shell color and high growth rate,the growth,survival rate and stability of triploid rate were analyzed at different development stages in the present study.Three different conditions inhibiting the release of polar body Ⅱ or polar body Ⅰ were tested:(A)Cytochalasin-B(CB),0.5mg L^(−1) at 10min post-insemination for 15 min;(B)CB,0.5mg L^(−1)at 15 min postinsemination for 20 min;and(C)CB,0.7mg L^(−1),at 15 min post-insemination for 20 min.The triploidy induction treatments significantly reduced the D-larvae and survival rates at the larvae stage but not at the juvenile and adult stages.Triploid rate dramatically decreased at the larval stage and did not significantly change at the juvenile and adult stages.Regarding the stability of the triploid rate,there was a significant difference between the three treatment groups.Larvae from the treatment A and control groups exhibited higher growth rates in shell height than those from the other two treatment groups at day 27.Triploid juveniles and adults from the treatment A group exhibited a higher wet weight than diploids from the control group and triploids from the other treatment groups.Triploidy induction did not affect the shell color of the progeny.The results obtained in the study demonstrate that triploidy induction has the potential to be used to increase the production of C.gigas variety‘Haida No.2’without modifying its golden shell color.

Selection of Media for Hardwood Cuttings Container Seedling-raising of Triploid Clones of Populus tomentosa

[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.

Establishment of in Vitro Regeneration System of Triploid Chinese White Poplar

初步建立了三倍体毛白杨 (PopulustomentosaCarr.)组织培养再生系统。组织培养时 ,外植体最好选用在弱光下从休眠芽上萌发的幼芽或嫩茎 ,经HgCl2 溶液表面消毒后 ,接种到大量元素减半、含 0 .2 5mg/L吲哚乙酸和 1.0 0mg/L玉米素的MS培养基上。试管苗的生根可采用含 0 .2 5mg/L吲哚丁酸和 10mg/L维生素B1的MS培养基。试管苗茎段的分化依无性系和外源激素条件的不同而异。无性系B19的茎段较易分化 ,而无性系B30 4和B331分化较难。最适的分化培养基为大量元素减半、含 0 .0 5～ 0 .10mg/L吲哚乙酸和 1.0

Comparison Between a Tetraploid Turnip and Its Diploid Progenitor(Brassica rapa L.):The Adaptation to Salinity Stress

Polyploidy is pursued in plant breeding programs due mainly to its ability to yield larger vegetative or reproductive organs. In controlled growth chamber experiments, a tetraploid turnip （cv. Aijiaohuang, 4n） and its diploid progenitor （cv. Aijiaohuang, 2n） were evaluated for their tolerance to salinity stress via investigations on a group of physiological parameters. The results indicate that the tetraploid turnip exhibit better adaptation to a high concentration salt medium （200 mmol L-1）, as evidenced by a less-affected germination rate and a healthier morphological appearance at the seedling stage. Furthermore, an extension of salinity stress up to a certain period of time at the 5-7-leaf stage shows differences between the tetraploid turnip and its diploid progenitor. The former had a higher K＋/Na＋ ratio in the roots, higher glutathione concentration and antioxidant activities in the leaves, and smaller reductions in photosynthetic capacity in terms of leaf chlorophyll content. Studies on the differences between an autopolyploid and its respective relative, from which the autopolyploid originated, in terms of their tolerance to salinity and/or other abiotic stresses, have remained rather limited. The comparison is interesting due to a homogenous genetic background.

Natural Homologous Triploidization and DNA Methylation in SARII-628,a Twin-seedling Line of Rice (Oryza sativa)

A total of five pairs of diploidotriploid twin-seedlings （a diploid seedling and a triploid seedling emerged from a grain） were selected out from 4500 pairs of seedlings from SARII-628, a twin-seedling rice line. SSR analysis indicated that no difference between the diploid seedling and corresponding triploid seedling in a twin-seedling was found at the 310 loci, indicating that there was no obvious change in DNA primary structure. A modified AFLP technique ＇MSAP （methylation-sensitive AFLP）＇ was used to analyze methylation mutation. Although no methylation mutation was noted among the five diploids, 29 methylation mutation loci were found from the corresponding triploids. This suggested that methylation mutation happened rapidly on Mogeneration after natural homologous triploidization. The mutations were classified into 10 types, including 3 increased types, 3 decreased types and 4 undecided types of methylation-degrees. The bands of 22 loci were sequenced and then those sequences were searched through website. The result showed that the methylation mutation involved into the whole rice genome and the 12 pairs of chromosomes. The mutation trend was site-related and there were different mutation loci for different triploids, which foretold that SARII-628 would have different evolution fates after natural homologous triploidization.

PRELIMINARY STUDY ON CHROMOSOMES OF INDUCED TRIPLOID IN THE RED SEA BREAM, PAGROSOMUS MAJOR

Triploidy red sea bream were induced by cold shock techniques (0 3℃) in Qingdao in April 1994, May 1995 and May 1996. Normal diploidy and triploidy chromosome metaphases were produced by chromosome spreads from the gastrula. Counts of 104 chromosome metaphases of normal diploid showed each of them consisted of 2 acrocentric (st) and 46 telocentric (t) chromosomes. Based on the relative lengths and arm ratios, the 48 chromosomes were matched into 24 pairs. Counts of 107 chromosome metaphases of induced triploid showed that each metaphase consisted of 3 acrocentric (st) and 69 telocentric (t) chromosomes. The 72 chromosomes were easily matched into three sets of chromosomes, based on the relative lengths and arm ratios.

Acute motor axonal neuropathy following anti-rabies human diploid cell vaccine:A rare case and review

Rationale:Guillain Barre syndrome(GBS)is an acute neurological illness leading to quadriparesis with respiratory involvement.It can be triggered by infections,vaccinations,surgery,trauma,transplantation and drugs.Anti-rabies cell culture vaccines introduced to overcome the high rate of neurological complications associated with tissue based rabies vaccine,can be very rarely associated with GBS.Patient concerns:A 50-year-old female presented with acute severe upper back pain evolving into pure motor quadriparesis following administration of human diploid cell vaccine for rabies.Diagnosis:Acute motor axonal neuropathy variant of GBS following anti-rabies human diploid cell vaccine.Interventions:Intravenous high dose steroids.Outcomes:Patient recovered completely within 1 month.Lessons:Although anti-rabies cell culture vaccines are highly immunogenic and safe,they are rarely associated with GBS.Clinicians should be aware of this link because prompt diagnosis and treatment can result in complete recovery and avoid complications.

Microsatellite-Centromere Mapping in Japanese Scallop(Patinopecten yessoensis) Through Half-Tetrad Analysis in Gynogenetic Diploid Families

Gene-centromere mapping is an essential prerequisite for understanding the composition and structure of genomes. Half-tetrad analysis is a powerful tool for mapping genes and understanding chromosomal behavior during meiosis. The Japanese scallop(Patinopecten yessoensis), a cold-tolerant species inhabiting the northwestern Pacific coast, is a commercially important marine bivalve in Asian countries. In this study, inheritance of 32 informative microsatellite loci was examined in 70-h D-shaped larvae of three induced meiogynogenetic diploid families of P. yessoensis for centromere mapping using half-tetrad analysis. The ratio of gynogenetic diploids was proven to be 100%, 100% and 96% in the three families, respectively. Inheritance analysis in the control crosses showed that 51 of the 53 genotypic ratios observed were in accordance with Mendelian expectations at the 5% level after Bonferroni correction. Seven of the 32 microsatellite loci showed the existence of null alleles in control crosses. The second division segregation frequency(y) of the microsatellite loci ranged from 0.07 to 0.85 with a mean of 0.38, suggesting the existence of positive interference after a single chiasma formation in some chromosomes in the scallop. Microsatellite-centromere distances ranged from 4 c M to 42 c M under the assumption of complete interference. Information on the positions of centromeres in relation to the microsatellite loci will represent a contribution towards the assembly of genetic maps in the commercially important scallop species.

Sequencing of a Cultivated Diploid Cotton Genome-Gossypium arboreum

Sequencing the genomes of crop species and model systems contributes significantly to our understanding of the organization,structure and function of plant genomes.In a `white paper' published in 2007,the cotton community set forth a strategic plan for sequencing the AD genome of cultivated upland cotton that initially targets less complex diploid genomes.This strategy banks on the high

Discovery of Triploid Allium macrostemon Bunge in Laizhou City of Shandong Province

[Objective]The study was to analyze the karyotype of Allium macrostemon Bunge in Laizhou City of Shandong Province.[ Method] The root tip of A. macrostemon was pretreated with 8-hydroxyquinoline solution, fixed, dissociated and stained for preparing the glass slide to reveal the chromosome number via the microscopic examination; the sparse cells with good chromosome morphology were photographed under microscope. [ Result ]Allium macrostemon Bunge in Laizhou City introduced in this study was tdploid; its somatic chromosome number was 24 and karyotype formula was K（2n） =3x=24m（2SAT） ＋ 1Bs, thus the karyotype belongs to 1A type. One of the chromosome No. 3 contained satellite, and chromosome deletion may be existed in one of the chromosome No. 5. In addition, B chromosome was observed in some cells.[ Conclusion] This introduction of triploid A. macrostemon found in China was the first time.

Genetic Control of Air-Dried Wood Density, Mechanical Properties and Its Implication for Veneer Timber Breeding of New Triploid Clones in Populus tomentosa Carr

The wood samples of 9 triploid clones of Populus tomentosa Carr. taken from a 9 year old clonal test site were analyzed in order to investigate the genetic variation of wood properties, including air dried wood density and some mechanical properties. The results showed that significant or extremely significant difference in air dried wood density and the mechanical properties existed among the clones, this means these wood properties were under moderate or strong genetic controls and could be improved by genetic manipulations. The radial and vertical variation patterns of air dried wood density were also studied and the results were found to coordinate with other previous research results. The vertical variation patterns of most mechanical properties within the individual tree also conformed to the general wood theories except the modulus of elasticity and cross section hardness. Among the mechanical properties, modulus of elasticity (MOE) and tangent section hardness were under strong genetic control, with the clonal repeatabilities being 0 90 and 0 80, respectively. However, the clonal repeatabilities of other mechanical properties under study were a little lower than above two indexes. Genetic correlation analysis indicated that super clonal selection and breeding for veneer timber could be realized through indirect selection of wood density and form indexes.

Genetic Diversity of Italian Ryegrass Diploid Cultivars, Revealed by Electrophoretically Detected Genotypes in Phosphoglucose Isomerase （PGI）

Nine diploid cultivars of Italian ryegrass （Lolium multiflorum Lain.） from France （Fortyl, Vertyl and Jericho）, Germany （Ligrande）, United Kingdom （Aber Epic and Aber Mario）, Denmark （Cordelia）, Netherlands （Alamo） and Poland （Tur） were tested with horizontal gel electrophoresis according to one locus （with four alleles） of the PGI enzyme system. One of them, named P4 is typical for the species, therefore can serve as a good marker for hybrids identification. Each cultivar was characterized by frequencies of different phenotypes. They were highly polymorphic （Pg = 0.58 - 0.78） and showed differences in heterozygosity level. The variability within populations （GST = 0.055） was higher than among populations （DST = 0.032）.

Artificial induction of androgenetic diploid in Yellow catfish(Pelteobagrus fulvidraco)

Androgenesis was the especial zoogamy that the germ plasma of offspring was from the agnate. In this study the eggs of Yellow catfish （Pelteobagrus fulvidraco） were irradiated by UV suspending in the synthetic ovarian fluid （OF）, and the total dosage of UV irradiation was 220 mJ·cm^-2. Diploid could be induced by heat shock （40℃, 2 min, 3 min） with different time period after fertilization （15-37 min）. The result showed that heat shock with 2 min was better than 3 min; there were two apices of induction in 17-21 min and 27-31 min after fertilization. The highest hatching rate was 3.30% at 29 min after fertilization, and the difference between two apices of induction was unobvious.

SAR-3——a resource of diploid true breeding hybrid rice

In 1988, we found strain 9003 from compositehybridization of indica and japonica. 9003 pos-sesses characteristics of twin seedlings withfrequency of 15-20% of the investigated popu-lation. The highest frequency was 45.68%.Afterwards, we discovered that some twinseedlings had variabilities in chromosome set.As to a pair of twin plants, it may be 2n-1n,2n-3n, 3n-3n or 1n-1n. The changes in chro-mosome set also occurred in the plants devel-oped from mono-embryo seeds. All of thesevariants nearly account for 1% in our con-trolled experiment. We named the triploidplants SAR-3 and found that SAR-3 could be aresource of diploid true breeding hybrid rice.

Evaluation of some Newly Developed Diploid Hybrids and their Breeding Value in 4x-2x Crosses

The narrow genetic base in potato (Solanum tuberosum L.) limits the progress in cultivar development.The rich diploid germplasm in the origin center of potato provide a unique resource for improvement of tetraploid potatoes.Seven newly developed diploid hybrids with 2n pollen production,all of which have S. phureja background,were developed and evaluated for their value in potato breeding.They were crossed as male parnets to six tetraploid Solanum tuberosum cultivars,and seeds in large quantity from eleven crosses were obtained.Main agronomic traits,such as tuber yield,tuber number,mean tuber weight,tuber shape,eye depth,skin smoothness,flesh color,and specific gravity,were measured for 4x 2x tetraploid progenies in seedling generation,and their parents as well.All of the diploid hybrids had some merit for specific traits and the DH39 was more promising;high specific gravity trait in some diploid hybrids was successfully introgressed into tetroploid progenies via 4x 2x crosses.These diploid hybrids have potential value in potato breeding.