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我国螨类研究的最新进展   总被引:9,自引:0,他引:9  
螨类是一种对人类危害极其严重的小型节肢动物,不论从人的健康方面还是农牧林生产方面来说都需要防治及至根除。主要钛螨类的形态特征、生活史、生态类群、对人类的危害及其防治等5个方面简述了我国螨类研究的最新研究进展概况。  相似文献   
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对710名(男328人,女382人)新疆蒙古族进行了糖精和乙酰水杨酸尝味能力的检测分析。结果表明,蒙古人群中的糖精味盲率为4.648%,没有尝味能力的隐性基因频率为0.2156,具有尝味能力的显性基因频率为0.7844,平均尝味阈值为8.009±1.34(0.108mol/L)。乙酰水杨酸的尝味阈值分布出现了非常明显的双峰一谷分布,表明该性状是单基因决定的性状,谷底7号液(3.00×10-4 mol/L)是味盲的界限,味盲的峰值在1号液(1.7×10-2mol/L),尝味者的峰值在11号液(1.25×10-5mol/L),味盲率为90.282%,。经χ2检验,男、女性的味盲率无显著差异(P>0.90),表明决定乙酰水杨酸尝味能力的基因位于常染色体,对该基因的显隐性等特点尚需通过家系分析进行确定。 Abstract:The saccharin and aspirin tasting abilities have been detected and analyzed in 710 individuals (328men,382women)of Xinjiang Mongol.It is showed that the saccharin taste- blindness ratio among Mongolians was 4.648%,frequency of the recessive gene determining taste-blindness and the dominant gene determining taste ability was 0.2156,and 0.7844 respectively,and its mean testable threshold was 8.00±1.34 (0.108mol/L).Distribution of aspirin tasting threshold appeared a distinct curve with double peaks and single bottom,and demonstrated the aspirin tasting ability was a monogenic character.Solution NO.7 (3.00×10-4mol/L) at the bottom in the curve was the boundary of taste-blindness.The peak of taste-blindness was at the solution NO.1 (1.7×10-2mol/L),and the peak of tasters was at the solution NO.11 (1.25×10-5mol/L),The ratio of aspirin taste-blindness was 90.28%.The χ2 test has been used to evaluate the statistical difference in aspirin taste-blindness ratio between male and female,the result showed that there was no significant difference (P>0.90),and the gene determining for aspirin tasting ability located on autosomes.  相似文献   
3.
新疆北部森林生态系统地衣植物生活型分析   总被引:2,自引:0,他引:2  
Life forms of lichen of forest ecosystem in Northern Xinjiang were researched in the Kanas National Natural Reservation Area.They have been grouped into 6 types:Epipetria,Soil-epipetria,Epiphytia arboricosa,Epiphytia moss,Epiphytis grass and Dry-radicantia,in which the species of Epiphytia arboricosa account for 36.89% of the total species in this area,the species of Epipetria for 22.33% and Epiphytia grass the least.The results show that life forms of lichem at the srea in Northem Xinjiang are relatively rich,which indicates the biodiversity characteristics of lichen.  相似文献   
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 根据多年的研究资料并采用聚类分析方法对分布在天山西部山脉的地衣群落结构进行了研究。结果表明,分布在该地区的地衣种类形成了6种群落:1) 土星猫耳衣(Leptogium saturninum)+矮石蕊(Cladonia humilis)+兰灰蜈蚣衣(Physcia caesia)群落;2)黑穗石蕊(Cladonia amaurocr  相似文献   
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Race 1 of Pseudomonas phaseolicola introduced into leaves of susceptible Canadian Wonder bean plants multiplied logarithmically for 3–5 days, reaching final populations about 105–106 times the original. In resistant Red Mexican, Race 1 multiplied less rapidly to give final populations about 102–103 times the original. Race 2 behaved in susceptible Red Mexican as did Race 1 in Canadian Wonder. Macroscopic symptoms appeared in leaves when bacterial numbers reached their maxima. When introduced into the cotyledonary node Race 1 moved more rapidly upwards than downwards, and more rapidly and farther in Canadian Wonder than in Red Mexican. But even in Canadian Wonder the bacterium appeared only sporadically above the node of the first compound leaf. It could be isolated only rarely from chlorotic haloes around necrotic areas in leaves, or from chlorotic leaves not carrying lesions. Fewer lesions developed and the bacteria multiplied less in older than in younger leaves. Addition of glucose and casein hydrolysate to inocula of Race 1, separately or together, had little effect on growth in Canadian Wonder or Red Mexican, and the bacterium grew equally well in extracts of susceptible and of resistant plants. Preinoculation of leaves with an avirulent race reduced the number of lesions caused by a virulent race inoculated later, and also reduced growth of this race in leaves of a susceptible variety.  相似文献   
9.
Two new species of Heliotropium L. (Boraginaceae, subfam. Heliotropioideae), growing in sandy loam soils in Jizan, south-west Saudi Arabia, Heliotropium chaudharyanum Al-Turki, Omer & A. Ghafoor and Heliotropium jizanense Al-Turki, Omer & A. Ghafoor, are described and illustrated. The relationships of the new species within the small-flowered Heliotropium europaeum L. species group are discussed. Notes on distribution and habitat are provided, together with a map.  相似文献   
10.
对710名(男328人,女382人)新疆蒙古族进行了糖精和乙酰水杨酸尝味能力的检测分析。结果表明,蒙古人群中的糖精味盲率为4.648%,没有尝味能力的隐性基因频率为0.2156,具有尝味能力的显性基因频率为0.7844,平均尝味阈值为8.009 ±1.34(0.108mol/L)。乙酰水杨酸的尝味阈值分布出现了非常明显的双峰一谷分布,表明该性状是单基因决定的性状,谷底7号液(3.00X10-4mol/L)是味盲的界限,味盲的峰值在1号液(1.7X10-2mol/L),尝味者的峰值在11号液(1.25X10-5mol/L),味盲率为90.282%,。经x2检验,男、女性的味盲率元显著差异(P>0.90),表明决定乙酰水杨酸尝味能力的基因位于常染色体,对该基因的显隐性等特点尚需通过家系分析进行确定。  相似文献   
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