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991.
以内蒙古乌梁素海人流水体为研究对象,考虑湖泊水质的随机性和灰色不确定性,以灰色概率统计理论为基础,引人灰色-随机风险率方法,通过计算并分析2006年、2007年和2008年入湖断面各水质参数存在的超标风险性,反映不同水质参数的污染强度和污染历时的变化过程.结果表明,入湖水体总氮总磷浓度超标风险率呈现逐年上升的趋势;总氮...  相似文献   
992.
利用2005—2010年250 m×250 m的EOS-MODIS卫星资料,通过预处理、几何校正,在C++环境下,进行水体判识与面积计算,对艾比湖湖区水域面积进行计算,得到逐旬的遥感动态监测数据,将其与同期气象台站的观测资料(温度、降水、风速、蒸发量)相结合,在SPSS中进行统计分析.结果表明:①艾比湖面积有显著的季节性变化,同一年内,由春到秋,艾比湖湖区水体面积总体呈现逐渐减少的趋势;湖区水域面积年内最大值多出现在春季,年内最小值多出现在秋季,但秋末湖区水域面积相对秋初又有所增加.②从年际变化来看,2005—2010年,艾比湖湖区水域面积呈现逐年减少的趋势;旬平均最高峰出现在4月中旬,且5月下旬湖区面积会出现次高峰,旬平均最小值出现在10月上旬,旬平均最高峰主要是山区融雪和降水的共同作用所致,次高峰主要是由降水所致.③相关分析表明,湖泊面积变化与温度、降水相关性不显著,但与风速有显著的正相关,与蒸发量有显著的负相关.  相似文献   
993.
Identification of genes related to flowering-time in Arabidopsis is very important and meaningful contribution to the flowering process control. One late flowering mutant plant, which exhibits 60-day delay in flowering, was screened from Arabidopsis library of T-DNA insertion. Southern blotting was used to confirm the single copy of exogenetic T-DNA in the genome of the mutant. The flanking sequence of T-DNA insert was obtained by TAIL-PCR and then analyzed by BLAST to confirm that the insertion site locates at the sixth exon of AT2G19520.1 (FVE gene). FVE is considered as a classical flowering time gene in Arabidopsis. It is a component of the autonomous pathway that encodes AtMSI4, which is a putative retinoblastoma-associated protein. The late-flowering mutant is named as fve-4, which is similar to fve-3 of Columbia and allelic with fve-1 and fve-2 of Landsberg erecta. The fve-4 mutant’s delay of flowering was longer than that of fve-3 mutant, whose T-DNA insertion is located at the first exon of FVE gene, suggesting that the sixth exon of FVE gene may play a more important role in the control of floral transition.  相似文献   
994.
A novel conidium development mutant was obtained by screening the transformants of Botrytis cinerea produced by Agrobacterium tumefaciens mediated method, which lost the ability of producing conidia. The flanking sequence of T-DNA insertion site was acquired by TAIL-PCR technology, and then, the T-DNA insertion in the second exon of BC1G_02800.1 confirmed by BLAST between the flanking sequence and the known sequence in the B. cinerea gene database. The mutant gene was identified as BC1G_02799.1 located in the upstream of BC1G_02800.1 gene by RTPCR. The DNA full-length sequence of BC1G_02799.1 was 1951 bp and contained 1848 bp coding region, which encoded a 615 amino acids putative protein similar to ABC-transporter, and the function of BC1G_02799.1 gene was unknown to date. Phenotype analysis of the mutant found that the mutant strain colony was white, grew slowly, and did not produce conidium and sclerotia on PDA medium but showed a stronger pathogenicity to tomato leaves and successfully increased the enzyme activity related to pathogenicity compared to the wild type strain. The results suggested that the BC1G_02799.1 gene was involved in the conidium development, the sclerotia formation, and pathogenicity in B. cinerea. Our research will facilitate in understanding the molecular mechanism of conidium development, sclerotia formation, and pathogenic in B. cinerea.  相似文献   
995.
The timing of floral transition is tightly controlled by a combination of endogenous and environmental signals. One early flowering mutant plant was screened from Arabidopsis library of T-DNA insertion to accelerate flowering under short-day condition, and a related-gene EFS1 (AT4G36680.1) was isolated and identified as a novel flowering-time gene of Arabidopsis in our preliminary studies. To investigate the function and the specific mechanism of EFS1 in the flower process control, the RNAi expression vector containing EFS1 gene-specific sequences in the sense and antisense orientations was constructed and transferred into Arabidopsis by using the floral-dip method, with 11 transgenic plants obtained through hygromycin B screening and PCR assays. The results showed that the expression level of EFS1 in transgenic lines was significantly lower than that in wild type and efs1 mutant. The flowering time of the efs1 mutant and RNAi transgenic plants was much earlier than that of wild-type plants. This result further verified that the EFS1 gene played an important role in flowering, and its specific mechanisms need further study. These work provided a foundation to further regulatory mechanisms of EFS1 in the control of floral transition.  相似文献   
996.
Based on the DNA sequence of ACS9, two produced fragments were subcloned into binary vector pCAMBIA1300 in antisense and sense orientations, and the generated RNA interference (RNAi) vector was then transformed into Arabidopsis thaliana. The stress resistance function of ACS9 gene in Arabidopsis thaliana was researched by determination of stress resistance physiologic indexes, NaCl and PEG6000 resistance. The results showed that the inhibition of ACS9 expression enhanced the sensitivity to high concentration NaCl (150 mmol/L) and PEG6000 (7%) in Arabidopsis thaliana seeding stage. The proline contents and water loss rates in transgenic plants were 0.68 and 1.4 times higher than those in the wild-type leaves, respectively, indicating that the inhibition of ACS9 expression due to salt and drought resistant was reduced and suggested that ACS9 gene played important roles in plant salt and drought tolerance.  相似文献   
997.
Using a PCR homology approach, DNA and cDNA sequences of calcium/calmodulin-dependent protein kinase (CaMK) gene of Botrytis cinerea were obtained. Southern blotting result displayed that CaMK was single copy in the genome of B. cinerea. The cDNA sequence of CaMK revealed an open reading frame of 2190 nucleotides encoding a 730 amino acid protein with predicted molecular weight of 81.8748 kDa. The genomic sequence of CaMK revealed the same ORF interrupted by six introns. Bioinformatics analysis showed that this protein had the distinctive features that characterize CaMK ATP binding region signature and serine/threonine protein kinase active-site signature. Pharmaceutical analysis displayed that the CaMK specific inhibitor, KN-62, could inhibit conidial germination, pathogenicity and herbicidal activity of B. cinerea BC4 strain. It was suggested that CaMK played an important role in regulating conidial germination, pathogenicity and herbicidal activity of B. cinerea.  相似文献   
998.
贵州省1984—2010年农区鼠情监测结果分析   总被引:2,自引:0,他引:2  
为研究农区鼠类种群组成及种群数量变化规律,并为其种群数量预测预报和防治提供科学依据。通过分析1984—2010年贵州省30个县(市、区)农区鼠情监测结果表明,贵州省家栖鼠类和农田鼠类隶属2目(啮齿目、食虫目)3科(鼠科、仓鼠科、鼩鼱科)18种,主要集中于鼠科,占总种数的77.78%,在区系组成上以东洋界种类占绝对优势,占总种数的66.67%。褐家鼠、黄胸鼠为家栖鼠优势种,分别占总鼠数的51.26%、29.16%,小家鼠为常见种,占总鼠数的16.80%;黑线姬鼠为农田区(稻田、旱地)害鼠优势种,占总鼠数的62.57%,褐家鼠、黄胸鼠为常见种,分别占总鼠数的12.29%、14.73%,在部分地区为农田害鼠优势种,高山姬鼠为黔西北部分地区优势种。贵州省农区灭鼠的重点是黑线姬鼠、高山姬鼠、褐家鼠、黄胸鼠、小家鼠5种害鼠,应将其列为贵州省主要的监测对象。住宅区混合鼠种种群数量明显高于农田区,种群数量呈明显的下降趋势,不同年度、不同时期、不同月份、不同季节种群数量存在明显差异。根据贵州省多年来的农区鼠害测报及防治实践,明确了农区鼠害监测及综合防治的技术路线,提出了一套切实可行的农区鼠害监测技术和综合防治配套技术。  相似文献   
999.
为研究人工合成的三肽囊素与胸腺九肽对伪狂犬和口蹄疫疫苗免疫效果的影响,选择40头体重相近的1月龄仔猪随机分为4组,接种伪狂犬疫苗1头份/头,同时,第I组注射10μg/kg的三肽囊素,第II组注射5μg/kg的胸腺九肽,第III组注射10μg/kg的三肽囊素和5μg/kg的胸腺九肽,第IV组注射等体积的生理盐水。1周后接种猪O型口蹄疫疫苗2头份/头,同时各试验组注射与前次等量的三肽囊素(10μg/kg)或胸腺九肽(5μg/kg),在伪狂犬疫苗注射后第1、2、3、4、6、7、8、9周采血,采用ELISA方法检测伪狂犬及口蹄疫抗体水平。研究结果表明,三肽囊素与胸腺九肽单独或联合应用均可提高伪狂犬及口蹄疫疫苗免疫后的抗体水平以及抗体的维持时间,说明三肽囊素与胸腺九肽可增强猪伪狂犬和口蹄疫疫苗的免疫效果。  相似文献   
1000.
以稳定黄瓜品系649为试材,经"实践8号"返回式育种卫星太空搭栽诱变后,与地面保留的对照进行田间对比试验,考察了卫星搭载后黄瓜649 SP0~SP2与对照的遗传变异情况.结果表明,在SP0代只有果实形状和果色发生变异,64个变异株系中只有部分变异遗传到SP1,SP1代在农艺性状上表现强烈的广谱变异,大部分变异能遗传到S...  相似文献   
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