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61.
62.
毛眼水蝇属(Hydrellia)中数种为稻、麦等农作物重要害虫。受害水稻会造成死秧、大发生年使水稻严重减产。笔者对安徽省水稻产区毛眼水蝇属进行调查,发现有10种,已鉴定出6种,其中有3个为我国新纪录种。本文将已鉴定出的种列出种的检索表和5个种的描述。 相似文献
63.
Fei Ge Jingtao Qu Peng Liu Lang Pan Chaoying Zou Guangsheng Yuan Cong Yang Guangtang Pan Jianwei Huang Langlang Ma Yaou Shen 《作物学报(英文版)》2022,(1):47-55
The current assembled maize genomes cannot represent the broad genetic diversity of maize germplasms.Acquiring more genome sequences is critical for constructing a pan-genome and elucidating the linkage between genotype and phenotype in maize.Here we describe the genome sequence and annotation of A188,a maize inbred line with high phenotypic variation relative to other lines,acquired by single-molecule sequencing and optical genome mapping.We assembled a 2210-Mb genome with a scaffold N50 size of 11.61 million bases(Mb),compared to 9.73 Mb for B73 and 10.2 Mb for Mo17.Based on the B73_Ref Gen_V4 genome,295 scaffolds(2084.35 Mb,94.30%of the final genome assembly)were anchored and oriented on ten chromosomes.Comparative analysis revealed that~30%of the predicted A188 genes showed large structural divergence from B73,Mo17,and W22 genomes,which causes high protein divergence and may lead to phenotypic variation among the four inbred lines.As a line with high embryonic callus(EC)induction capacity,A188 provides a convenient tool for elucidating the molecular mechanism underlying the formation of EC in maize.Combining our new A188 genome with previously reported QTL and RNA sequencing data revealed eight genes with large structural variation and two differentially expressed genes playing potential roles in maize EC induction. 相似文献
64.
Soybean bacterial spot disease caused by Pseudomonas syringae pv.Glycinea which is a bacterial disease seriously affects soybean yield.Ten soybean germplasms and recombinant inbred lines (RILs) population were used to identify the resistant trait after inoculated with P.sg (P.sgneau001) in this study.High-density genetic mapping was obtained by specific length amplified fragment sequencing (SLAF-seq) of 149 RILs population which was derived from the crossing between Charleston and Dongnong594.The results indicated that 10 germplasm resources had four resistant germplasms included highly resistant cultivar Charleston,four susceptible varieties included Dongnong594 and two moderately resistant cultivars.Five quantitative trait locus (QTLs) were detected in RILs population by the composite interval mapping (CIM) method,and located on Linkage Group (LG) D1b (chromosome two),LG C2 (chromosome six) and LG H (chromosome 12),respectively.LOD scores ranged from 2.68 to 4.95 and the phenotypic variation percentage was from 6% to 11%.Six candidate genes were detected,according to the result of gene annotation information.Four of them had relationship with protein kinase activity,protein phosphorylation and leucine rich repeat (LRR) transmembrane protein,which had high expression after inoculated with P.sg by qRT-PCR. 相似文献
65.
66.
美国农业部梅岛国外病研究中心(PIADC)的非洲猪瘟专家潘英章博士应农牧渔业部邀请,于1985年5月来我国讲学,这是他讲的部分学术资料,现整理发表,供参考。 相似文献
67.
Pan Delu Wang Jingxin Northeast Forestry University 《林业研究》1991,2(2):77-82
The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the formation and development of three kinds of log production lines innortbeast forest areas of China.It gives different combination types of log production lines andtheir applications, so it is significant for us to evaluate and standardize the log Production lines. 相似文献
68.
Objective To determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The effect of breed, sex and age of dogs and season on the presence or absence of bacteria in the conjunctival sac of clinically normal dogs was evaluated. Sample population This investigation included 240 healthy dogs, 27 dogs with unilateral corneal ulcer and one dog with bilateral corneal ulcer. Procedure The 480 samples from healthy dogs and the 29 samples from dogs with ulcerative keratitis were incubated in an aerobic and 5% CO2 environment at 37 °C for 48 h. Logistic regression analysis was performed. Statistical significance was set at P < 0.01. Results Of 480 normal eyes, Staphylococcus spp. were the most frequently isolated organisms (40.29%). Neisseria spp. (11.47%) were the next most frequently isolated organisms, followed by Corynebacterium spp. (9.4%). Of 29 eyes with ulcerative keratitis, Staphylococcus spp. were also the most frequently isolated bacteria (47.06%). Streptococcus spp. (12.94%) and Pseudomonas spp. (8.24%) were the second and third, respectively. Season (P = 0.002) was a significant factor influencing presence or absence of bacterial microorganisms in the conjunctival sac of normal dogs in Beijing, China, while the effects of breed (P = 0.095), sex (P = 0.588) and age (P = 0.866) of dogs were insignificant. Conclusion Staphylococcus spp. were the most frequently isolated organisms, and S. intermedius predominated in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The likelihood of detecting bacteria depends on the season. 相似文献
69.
In this paper,the effects of quality of gangue amount ofCaO added and w/c ratio upon the weight loss rate and potential of steelas well as pH value and structure of concrete cover of gangue concreteare analysed by means of mercury intrusion porosimetry,scanning electronmicroscopy,pH value measurement and soak-dry cycling.The results ofthis study confirm that the gangue concrete with appropriate proportiongives a good protection for steel. 相似文献
70.
Wang Ding Pan Wu Wang Tao 《保鲜与加工》1997,(6):62-66
This article describes the diffraction efficiency,resolution and colour purity of synthetic slit rainbow holograms.A formula is given to express the relation between the diffraction efficiency and the synthetic slit width.It is proved that the resolution and the colour purity of this holograms are both lower than the ordinary rainbow holograms. 相似文献