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991.
番茄内生细菌种群动态分析及拮抗菌株的筛选 总被引:3,自引:3,他引:3
摘要:采用研磨组织稀释分离法对3个种植地区的番茄内生细菌的种群分布、数量变化规律进行了初步探讨。共分离、纯化得到内生细菌374株,经形态及理化特征鉴定,分属10个不同的属,13个种。其中假单孢菌属Pseudomonas sp.,黄单孢菌属Xanthomonas sp.;肠杆菌属Entenobacter sp.和芽孢杆菌属Bacillus sp.为优势种群。内生细菌在番茄植株种群数量从0.21x104 到13.82x104 cfu.g -1鲜重之间,但不同品种、组织、生育期及种植地,内生细菌的种群和数量各不相同,各组织中内生细菌的种群及数量根中最多,其次是茎和叶,成株期内生细菌无论种类和数量都明显高于苗期。采用平板对峙法从分离的内生细菌中筛选出对番茄灰霉病菌具有体外拮抗活性的菌株32个,占菌株总数的8.56%; 25个菌株对叶霉病菌有抑制作用,占菌株总数的6.68%;对灰霉病菌和叶霉病菌都具有拮抗作用的菌株20个,占菌株总数的5.35%。对灰霉病菌有强拮抗作用的菌株12个,对叶霉病菌有强拮抗作用的菌株仅1个,其中芽孢杆菌是主要的类群。 相似文献
992.
Xiaoshuang Wei Bowen Guo Yun Tuo Fudong Tian Zheng Han Xueying Wang Wenbin Li Shanshan Liu 《Plant Breeding》2014,133(5):638-648
The development of soybean varieties that lack the β‐conglycinin α‐subunit is an attractive goal because the β‐conglycinin α‐subunit negatively influences the nutrition and gelation of tofu and is a major allergen. To remove this undesirable allergen and simultaneously improve the seed nutritional value and food‐processing quality, marker‐assisted background selection (MABS) was used in backcross breeding to incorporate cgy‐2, a null phenotype version of the gene encoding the β‐conglycinin α‐subunit, from the donor line ‘RiB’ into the genetic background of the Chinese cultivar ‘Dongnong47’ (DN47), a popular high‐oil superfine seed soybean cultivar from Heilongjiang Province, China. In each F2 (F2, BCnF2) generation of the breeding programme, the offspring that carried the introgressed cgy‐2 were identified by sodium dodecyl sulphate–polyacrylamide gel electrophoresis and rescreened by MABS using simple sequence repeat markers to accelerate recurrent parent genome recovery. Of the 49 advanced backcrossing breeding lines (ABLs), the three best lines, ABL1, ABL2 and ABL3, were selected from the BC1, BC2 and BC3 populations, respectively. The ABLs were evaluated for desirable agronomic characteristics, yield‐related traits, amino acid composition, free amino acid composition and tofu‐processing quality in the mature seeds. All of the ABLs lacked the α‐subunit but grew and reproduced normally without deleterious effects on physiological processes such as seed development and germination. The free amino acid content of ABL1 was significantly higher than that of ‘DN47’, with arginine (Arg) being particularly enriched. Compared to the recurrent parent ‘DN47’, the total protein content of the three ABLs was higher, the amino acid composition of the seed proteins was markedly modified and the yield and hardness of the tofu that was made from the ABLs were significantly increased. MABS combined with stringent phenotypic selection in a backcross breeding programme is a feasible strategy for the genetic engineering of seed protein components to produce allergenic subunit‐deficient variant alleles. 相似文献
993.
994.
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
995.
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
996.
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
997.
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
998.
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
999.
1000.
以巢湖油菜田优化施肥(YH)、秸秆施肥(JG)、习惯性施肥(CG)和不施肥(CK)4种施肥类型为研究对象,利用静态箱--气相色谱法测定了油菜生长期间的CH4的排放通量,同时对土温、土壤含水量和空气湿度进行测定,得出油菜田温室气体CH4的排放通量有明显的时间变化特征。与CK相比,YH、CG、JG 3种施肥类型下CH4的排放分别增加了21.50%、27.33%、29.87%。通过对数据进行相关性分析,实验期间CH4的排放通量从整体上与10 cm以下温度正相关、YH处理的土壤含水率与CH4通量在0.05水平显著正相关。 相似文献