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911.
彩色马蹄莲2n配子育种技术初探 总被引:2,自引:0,他引:2
以彩色马蹄莲的栽培品种‘黒魔术’Black magic、‘火烈鸟’Flamingo为实验材料,研究彩色马蹄莲2n配子育种技术。选择刚从茎秆中抽出的幼小健壮小花,用0.15%的秋水仙素处理以诱导2n配子,将诱导的2n配子进行不同组合的杂交实验。结果表明:秋水仙素处理对彩色马蹄莲雄雌蕊发育有一定毒副作用,其中对雌蕊的损伤大于雄蕊;2n配子能在一定程度上克服杂交后代不育性;在相同条件下,经2n配子诱导处理的杂交种子与未处理的对照种子相比,种子萌发时间大幅度缩短(50天左右),叶片变薄、变大、叶色变浅,有些杂交植株表现出不同程度的畸变。通过对杂交后代的细胞学鉴定表明:处理配子杂交后代中获得染色体数目为48(2n=3x=48)的三倍体植株。 相似文献
912.
玫瑰茄粗多糖清除DPPH自由基活性研究 总被引:1,自引:0,他引:1
以玫瑰茄干花萼为原料,利用水浸醇析法提取玫瑰茄粗多糖,其抗氧化活性用清除1,1-二苯基苦基苯肼(DPPH)自由基的能力进行评价。结果表明,玫瑰茄粗多糖具有良好的抗氧化活性,其浓度在0.551~2.150 mg/mL范围内,与清除率呈较好的线性关系:y=28.7684x+39.43208,R=0.973。 相似文献
913.
以4个不同的六倍体裸燕麦品种和普通小麦进行正反杂交,确定裸燕麦和普通小麦的可交配性。调查杂种结实率并诱导杂种愈伤组织。结果表明:六倍体裸燕麦与普通小麦的可交配性和愈伤组织诱导率因品种和正反交方式的不同而不同。在以六倍体裸燕麦为母本的正交试验中,‘白燕2号’母本结实率最高,为12.98%。在以六倍体裸燕麦为父本的反交试验中,‘白燕5号’为父本时结实率最高,为6.25%。相同品种间正反交结实率也有差异。4个裸燕麦品种与春小麦的杂种胚均有较高的愈伤组织诱导率。此研究对燕麦的优异基因资源的利用和裸燕麦、小麦种质创新具有重要的理论和现实意义。 相似文献
914.
915.
Tomatoes are the most important vegetable, globally as well as in Germany. Outdoor tomato production is seriously impaired
due to increasing infections with evolving late blight (Phytophthora infestans) populations. Within organic agriculture, research is being conducted to develop regionally adapted and open pollinated cultivars
of outdoor tomatoes with late blight field resistance. In the present experiment, three crosses, including wild, cocktail,
and beefsteak tomatoes, were selected for field resistance against late blight in F2 at one location per cross. The comparison of positive and negative selection in F3 revealed the selection of single F2 plants to be efficient in all three crosses. F2 selection has proved to be a robust and efficient tool for breeding programs. The correlated response to selection in other
traits, including yield, fruit weight, days to maturity, harvest period, and plant height, depended on the cross. It was evident
that selection for desired traits combined with field resistance against late blight is promising, even in wide crosses. The
most undesired attribute of wild tomatoes is the formation of shoots on leaves and in inflorescences. No correlation was observed
between field resistance and shoot formation, allowing the selection of genotypes with improved field resistance and yield,
but without morphological disadvantages. 相似文献
916.
Dong Fu Liang Chen Guohui Yu Yi Liu Qiaojun Lou Hanwei Mei Liang Xiong Mingshou Li Xiaoyan Xu Lijun Luo 《Euphytica》2011,180(2):209-218
Sheath blight, caused by the pathogen Rhizoctonia solani Kühn, is one of the most serious diseases of rice and leads to severe yield loss worldwide. A recombinant inbred line (RIL)
population consisting of 121 lines was constructed from a cross between HH1B and RSB03, the latter of which is a deep-water
rice variety. Five traits were used to evaluate sheath blight resistance, namely disease rating (DR), lesion length (LL),
lesion height (LH), relative lesion length [RLL, the ratio of LL to plant height (PH)], and relative LH (RLH, the ratio of
LH to PH). Using the RIL population and 123 molecular markers, we identified 28 quantitative trait loci (QTLs) for the five
traits in two environments. These QTLs are located on nine chromosomes and most of them are environment specific. A major
QTL for DR (qSBR1) on chromosome 1 was identified with contributions of 12.7% at Shanghai and 42.6% at Hainan, and it collocated with a QTL
for PH. The allele at this locus from RSB03 enhances sheath blight resistance and increases PH. Another QTL for DR on chromosome 7
was adjacent to QTLs for heading date (HD) and four other disease traits. RSB03 also carries the resistant allele at this
locus and shortens HD. The susceptible parent, HH1B, provides the resistance allele at the locus qSBR8, where QTLs for four other disease traits were identified. QTL mapping results showed that most QTLs for LL, LH, RLL, and
RLH are collocated with QTLs for DR. Three QTLs for DR are independent from HD, PH, and four other disease traits, while four
QTLs are closely related to HD and PH. Four QTLs for LL, LH, RLL, and RLH are independent from DR, HD, and PH, while there
is only one region harboring QTLs for these four traits and HD. Correlation analysis and QTL mapping results indicated that
LL, LH, RLL, and RLH might be important indices, like DR, for evaluating the level of resistance to rice sheath blight. 相似文献
917.
Low temperature is a serious abiotic stress affecting rice production in subtropical and temperate areas. In this study, cold
tolerance of rice at the germination and seedling stages were evaluated using one recombinant inbred line (RIL) population
derived from a cross between Daguandao (japonica), with highly cold-tolerant at the seedling stage, and IR28 (indica), with more cold-tolerant at the germination stage, and the quantitative trait loci (QTL) mapping was conducted using the
multiple interval mapping (MIM) approach. Continuous segregation in low temperature germinability (LTG) and cold tolerance
at the seedling stage (CTS) were observed among the RIL populations. Most RILs were moderately susceptible or tolerant at
the germination stage, but were susceptible at the seedling stage. No significant relationship was found in cold tolerance
between the germination and seedling stages. A total of seven QTLs were identified with limit of detection (LOD) >3.0 on chromosomes
3, 8, 11 and 12, and the amount of variation (R
2) explained by each QTL ranged from 5.5 to 22.4%. The rice LTG might be regulated by two minor QTLs, with the CTS controlled
by one major QTL [qCTS8.1 (LOD = 16.1, R
2 = 22.4%)] and several minor loci. Among these loci, one simultaneously controls LTG (qLTG11.1) and CTS (qCTS11.1). Several cold-tolerance-related QTLs identified in previous studies were found to be near the QTLs detected here, and three
QTLs are novel alleles. The alleles from Daguandao at six QTLs increased cold tolerance and could be good sources of genes
for cold tolerance. In addition, only one digenic interaction was detected for CTS, with a R
2 value of 6.4%. Those major or minor QTLs could be used to significantly improve cold tolerance by marker-assisted selection
(MAS) in rice. 相似文献
918.
András Cseri Mátyás Cserháti Maria von Korff Bettina Nagy Gábor V. Horváth András Palágyi János Pauk Dénes Dudits Ottó Törjék 《Euphytica》2011,181(3):341-356
In the present study, allele mining was conducted on a panel of drought related candidate genes in a set of 96 barley genotypes
using EcoTILLING, which is a variant of the targeting induced local lesions in genomes (TILLING) technology. Analyzing approximately
1.5 million basepairs in barley a total number of 94 verified unique haplotypes were identified in 18 amplicons designed for
9 genes. Overall, 185 single nucleotide polymorphisms (SNPs) and 46 insertions/deletions (INDELs) were detected with a mean
of 1SNP/92 bp and 1INDEL/372 bp genomic sequence. Based on overlapping haplotype sequences, markers were developed for four
candidate genes (HvARH1, HvSRG6, HvDRF1, HVA1), which allows distinguishing between the main haplotypes showing either differences in amino acid sequence or which have
larger INDELs in the promoter region. As “proof of concept”, the HvARH1 and HvSRG6 haplotypes were tested for the level of abscisic acid-induced gene expression in subsets of genotypes belonging to different
haplotype categories. An integrated database was developed to contain information about the genes, genotypes, and haplotypes
analyzed in this study. The database supplies profound information about the natural variation in the tested drought related
candidate genes providing a significant asset for further mapping studies dealing with this highly polygenic trait. 相似文献
919.
Edak Aniedi Uyoh Ikootobong Sunday Urua Valentine Otang Ntui Elza Cletus Okpako 《Journal of Crop Science and Biotechnology》2011,14(4):227-232
Nuclear DNA of three accessions of Parkia biglobosa collected from three locations in northern Cross River State was investigated using a Patec PA II flow cytometer equipped
with an argon ion laser (488 nm), and pictures of mitotic chromosomes were taken using a digital micro-camera (Canon) placed
on the eye piece of a binocular microscope at 100X oil immersion. Metaphase chromosome counts of 2n = 22 for accessions A
and C and 2n = 24 for accession B, were obtained and through flow cytometry, the three accessions were confirmed to be diploids.
The nuclear DNA content and genome size for the accessions were 1.5085, 1.489, and 1.5266 pg (737.7054, 728.121, and 746.5074
Mbp) for accessions A, B, and C, respectively. In another experiment, leaf samples from greenhouse-germinated seeds were analyzed
for variation in the banding pattern of the protein by SDS-PAGE in the three accessions. Protein was resolved into three banding
groups according to their electrophoretic mobility: slow, medium, and fast, clustering between 100–200, 40–70, and 10–25 kDa,
respectively. There was 76% similarity in the banding pattern between the accessions. 相似文献
920.
Mi-Young Kang Catherine W. Rico Sang-Chul Lee 《Journal of Crop Science and Biotechnology》2011,14(2):111-118
The physicochemical properties of pigmented (Midorimochi, Jeokjinjubyeo, and Heukmichalbyeo) and non-pigmented (Hwayoungbyeo)
rice varieties were investigated. Starch from non-pigmented rice consisted mainly of large polyhedral granules that were more
loosely packed than those of the non-pigmented sample. Pigmented rice showed higher linoleic acid content (36–40%) and hydrolysis
rate (63–79%) but lower oleic acid content (35–39%), blue value (0.05–0.17), and viscosity values than the non-pigmented one.
Significantly higher mineral content, blue value, and pasting and viscosity values were observed in the Jeokjinjubyeo sample
compared to those of the other pigmented rice samples. The Midorimochi variety, on the other hand, exhibited the highest total
amino acid (816.82 ng mg−1) and sugar (0.15–3.35 μg g−1) contents and the lowest pasting and viscosity values. No substantial difference in the X-ray diffraction pattern was observed
among the samples. Results of this study could serve as baseline information for the quality evaluation of three pigmented
rice cultivars and provide a better understanding of their potential uses and food industry applications. 相似文献