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1.
A totatl of 116 isolates of rice blast fungus, Magnaporthe oryzae, were collected from 45 samples in different counties of Heilongjiang Province, and 20 Chinese physiological races belonging to seven groups were identified by using seven standard Chinese rice blast identifying varieties. Results showed that the dominant groups could be ranked as ZA, ZD, and ZB, with the occurrence frequencies of 47.41%, 22.41% and 15.52%, respectively. The race ZA49 was the dominant race with the occurrence frequency of 26.72%. The occurrence frequencies of the races ZD5 and ZD1 were 10.34% and 8.62%, respectively. The rising occurrence frequencies of these three dominant species were the most important reasons that causing Kongyu-131 more sensitive to rice blast. The results of virulence frequency indicated that the race harboring Pi-k, Pi-i, Pi-a gene were more susceptible to rice blast in Heilongjiang Province, and they should not be large-scale cultivated.  相似文献   
2.
为了解浙北山地丘陵小麦田杂草的发生种类和群落结构,实现麦田杂草的可持续治理,在浙北山地的典型麦区仙居县开展杂草调查,进行群落多样性和聚类分析。结果表明,仙居县小麦田杂草共34种,隶属于16科,相对优势度大于10%的杂草依次为看麦娘、牛繁缕、碎米荠。对53块样田的多样性进行研究,Simpson指数平均值为0.70,Shannon-Wiener指数平均值为1.53,Pielou指数平均值为0.74,Margalef指数平均值为1.08。聚类分析结果表明,杂草群落可分为4个类群。类群1优势种为看麦娘、臭独行菜、猪殃殃。类群2优势种为牛繁缕、野老鹳草、臭独行菜、婆婆纳。类群3和类群4的优势种均为看麦娘、牛繁缕、碎米荠,但3种杂草在这2个类群里的相对优势度存在差异。综上所述,仙居恶性杂草为看麦娘、牛繁缕,区域恶性杂草为碎米荠,宜选择氟噻草胺、甲基二磺隆、噻吩磺隆3种除草剂搭配除草。  相似文献   
3.
An allele of CYP6BQI3, named CYP6BQ 13v2 (GenBank accession no. FJ209361), was isolated from the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) by RT-PCR. The cDNA sequence of CYP6BQ13v2, 1 563 bp in length, contains an open reading frame of 1 554 nucleotides encoding a putative protein of 518 amino acid residues with a predicted molecular weight of 59.92 kDa and a theoretical pl of 7.60. The putative protein contains the classic hemebinding sequence motif F××G×××C×G (residues 456-465) conserved among all P450 enzymes as well as other characteristic motifs of all cytochrome P450s. It shares 98% identity with the previously published sequence of CYP6BQ13 (GenBank accession no. XP967146) from the T. castaneum genome project. Phylogenetic analysis of amino acid sequences from members of various P450 families indicated that there was closer phylogenetic relationship of CYP6BQ 13v2 with CYP302A1 and CYP307A1 mediating synthesis of the insect molting hormone, distant relationship with CYP6B1 metabolizing plant allelochemicals, CYP6D 1 linking to pyrethroid resistance and other members of CYP6 family. Expression test of the gene in the adults and immature stages of T. castaneum by quantitative real-time PCR revealed that CYP6BQ13v2 is expressed in all life stages investigated. The mRNA expression level in 1st instar larvae was 14.9- and 3.86-fold higher than those in pupae and adults, respectively. The CYP6BQ13v2 expression levels appeared in the order of 1st instar larvae, followed by 4th instar larvae, 7th instar larvae, adult, and pupae from high to low. The more bioinformation of CYP6BQ 13v2 was also analyzed.  相似文献   
4.
瓜列当发芽诱导植物的筛选及寄生关系研究   总被引:1,自引:0,他引:1  
选用部分中草药和新疆本地能产生可观经济效益的栽培作物为研究材料,研究其蒸馏水和甲醇浸提液原液及其50、100、250、500、1000、2500、5000和10000倍稀释液对瓜列当种子发芽的影响及植物幼苗-番茄寄生情况。结果表明,大部分植物浸提原液对瓜列当种子的发芽具有一定的抑制作用,28种植物组织的蒸馏水浸提液和19种植物组织的甲醇浸提液分别在其不同稀释倍数下对瓜列当种子的发芽具有有不同程度的诱导作用;有菌和无菌的室内寄生模拟试验发现,根际环境是除发芽刺激物质外影响瓜列当-寄主寄生关系的另一主要因素。  相似文献   
5.
李继武  唐文浩 《安徽农业科学》2009,37(13):6112-6113
以西昌市城市污水厂为例,结合DE氧化沟污水处理工艺,研究活性污泥培养的相关问题。  相似文献   
6.
[Objective] This study aimed to investigate the acaricidal effect of scopoletin, and provide the biochemical evidences of scopoletin influences Ca2 +-ATPase activity and gene expressions in the Carmine Spider Mite, Tetranychus cinnabarinus.[Method] The acaricidal effects of scopoletin were investigated by slip-dip method.Exposeed to different concentrations of scopoletin(0.16-2.5 mg/ml), Ca2+-ATPase activity in vivo and protein contents were investigated. For assessing the in vitro effect, Ca2+-ATPase enzyme(200 μl) prepared from normal mites were incubated with different concentrations of scopoletin reagents. [Result] Scopoletin exhibited significant inhibitory effect on Ca2+-ATPase activity both in vivo and in vitro, and resulted in increased protein contents; kinetic analysis showed that the catalytic capability of Ca2+-ATPase was significantly reduced by scopoletin. [Conclusion] Scopoletin exhibits a significant inhibitory effect on Ca2 +- ATPase, and its acaricidal effect against T. cinnabarinus might be due to the direct inhibition of Ca2+-ATPase.  相似文献   
7.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most widespread and destructive wheat diseases in many wheat-growing regions of the world. The winter wheat translocation line H9014-14-4-6-1 has all stage resistance. To identify stripe rust resistance genes, the segregating populations were developed from the cross between H9014-14-4-6-1 and Mingxian 169 (a wheat cultivar susceptible to all Pst races identified in China). The seedlings of the parents and F 1 plants, F2 , F3 and BC 1 generations were tested with Pst races under controlled greenhouse conditions. Two genes for resistance to stripe rust were identified, one dominant gene conferred resistance to SUN11-4, temporarily designated YrH9014 and the other recessive gene conferred resistance to CYR33. The bulked segregant analysis and simple sequence repeat (SSR) markers were used to identify polymorphic markers associated with YrH9014. Seven polymorphic SSR markers were used to genotype the F2 population inoculated with SUN11-4. A linkage map was constructed according to the genotypes of seven SSR markers and resistance gene. The molecular map spanned 24.3 cM, and the genetic distance of the two closest markers Xbarc13 and Xbarc55 to gene locus was 1.4 and 3.6 cM, respectively. Based on the position of SSR marker, the resistance gene YrH9014 was located on chromosome arm 2BS. Amplification of a set of nulli-tetrasomic Chinese Spring lines with SSR marker Xbarc13 indicated that YrH9014 was located on chromosome 2B. Based on chromosomal location, the reaction patterns and pedigree analysis, YrH9014 should be a novel resistance gene to stripe rust. This new gene and flanking markers got from this study should be useful for marker-assisted selection (MAS) in breeding programs for stripe rust.  相似文献   
8.
Effects of low temperature and INA bacteria on the change of chlorophyll a fluorescence inyoung fruit from two apricot cultivars were investigated. Low temperature decreased the potential activity(Fv/Fo) ,conversion efficiency of primary light energy (Fv/Fm)of PS Ⅱ and photochemical quenching (qP) inyoung fruit of two apricot cultivars. Low temperature enhanced non-photochemical quenching qN, decreasingthe quantum yield of photosynthetic electron transfer. The presence of ice nucleating active (INA) bacteria in-tensified the effects of low temperature, raised the injury temperature threshold from - 4℃ to - 2 - - 3℃.INA bacteria can be a factor to induce frost susceptibility of apricot fruit. The amount of damaged PS Ⅱ activi-ty center was related to apricot fruit size and cultivar.  相似文献   
9.
望都县苹果幼果期日灼病的发生情况及预防对策   总被引:1,自引:0,他引:1  
2010年7月中旬在望都县万亩苹果基地抽查3个套袋苹果品种,调查果实日灼率发生情况。结果表明:套纸袋的\"富士\"和\"斗南\"日灼率为11%和14%,套塑料膜袋的\"王林\"日灼率为26%。对气象资料分析发现,7月5日和6日的高温、强日照天气可能是导致此次苹果日灼病发生的主要原因,并据此提出了预防苹果日灼病的相关对策。  相似文献   
10.
针对柑橘老熟组织中富含多糖、多酚、色素和其它次生代谢产物的特点,以柑橘老叶老皮为试材,在传统CTAB提取法的基础上通过添加增效剂并优化配方,建立了一种快速、简便的提取植物老熟组织及其内部病原总核酸的CTAB-Triton提取法。新的提取液对细胞的裂解能力更强,且解决了传统CTAB溶液因低温析出而致DNA得率损失的弊端。比较了该法和微量葡聚糖柱纯化法制备模板时韧皮部杆菌的检出率,并用该法制备模板,分析了韧皮部杆菌在柚子叶片中的分布情况,及对其它几种柑橘病原菌进行PCR/RT-PCR检测。结果表明,CTAB-Triton方法能有效提取柑橘老熟叶片的DNA,所得DNA质量高,产量比商品化试剂盒大,提高了韧皮部杆菌的检出率,且可用于柑橘其他病原真菌、细菌,以及DNA或RNA病毒病害的PCR/RT-PCR检测,也可用于定量PCR检测和病原种群多态性分析。  相似文献   
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