排序方式: 共有74条查询结果,搜索用时 343 毫秒
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对产于渭河试验站的秦黑卜杨、秦黑青杨1号和秦黑青杨2号3种秦黑杨杂交新品种对照陕林4号杨木进行木材纤维形态和物理力学性质研究。秦黑卜杨、秦黑青杨1号、秦黑青杨2号和陕林4号杨木的纤维长度分别为987.5、1 064、1 087、935 μm;木纤维长宽比分别为42.75、41.3、42.35、44.9;气干密度分别为0.44、0.42、0.42、0.49 g/cm3;体积干缩系数分别为0.40%、0.33%、0.28%、0.26%;顺纹抗压强度分别为36.46、34.79、36.21、46.29 MPa;抗弯强度分别为63.18、60.52、61.89、81.34 MPa;抗弯弹性模量分别为6 896.67、6 339.21、6 627.16、8 082.40 MPa;综合强度分别为99.64、95.31、98.10、127.63 MPa。结果表明,3种秦黑杨新品种的木纤维长度均大于陕林4号,木纤维长宽比略小于陕林4号;3种秦黑杨新品种的物理力学性质指标均小于陕林4号,但干缩系数大于陕林4号。综合分析纤维形态和物理力学性质指标,作为纤维工业用材,3种秦黑杨新品种优于陕林4号,3种秦黑杨新品种是较为理想的造纸和纤维工业用材;作为结构用木材,陕林4号优于3种秦黑杨杂交新品种。 相似文献
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以葛牌文化旅游古镇为例,从古镇规划建设思路、发展定位、游憩系统结构等方面对文化旅游古镇建设进行探讨,以期为古镇提出操作性强的文化旅游发展策略,指导以旅游为引导的新型文化旅游古镇发展建设. 相似文献
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Triticum aestivum-Hayaldia villosa translocation line V3 has shown effective all-stage resistance to the seven dominant pathotypes of Puccinia striiforms f.sp.tritici prevalent in China.To elucidate the genetic basis of the resistance,the segregating populations were developed from the cross between V3 and susceptible genotype Mingxian 169,seedlings of the parents and F 2 progeny were tested with six prevalent pathotypes,including CYR29,CYR31,CYR32-6,CYR33,Sun11-4,and Sun11-11,F 1 plants and F 3 lines were also inoculated with Sun11-11 to confirm the result further.The genetic studied results showed that the resistance of V3 against CYR29 was conferred by two dominant genes,independently,one dominant gene and one recessive gene conferring independently or a single dominant gene to confer resistance to CYR31,two complementary dominant genes conferring resistance to both CYR32-6 and Sun11-4,two independently dominant genes or three dominant genes(two of the genes show cumulative effect) conferring resistance to CYR33,a single dominant gene for resistance to Sun11-11.Resistance gene analog polymorphism(RGAP) and simple-sequence repeat(SSR) techniques were used to identify molecular markers linked to the single dominant gene(temporarily designated as YrV3) for resistance to Sun11-11.A linkage map of 2 RGAP and 7 SSR markers was constructed for the dominant gene using data from 221 F 2 plants and their derived F 2:3 lines tested with Sun11-11 in the greenhouse.Amplification of the complete set of nulli-tetrasomic lines of Chinese Spring with a RGAP marker RG1 mapped the gene on the chromosome 1B,and then the linked 7 SSR markers located this gene on the long arm of chromosome 1B.The linkage map spanned a genetic distance of 25.0 cM,the SSR markers Xgwm124 and Xcfa2147 closely linked to YrV3 with genetic distances of 3.0 and 3.8 cM,respectively.Based on the linkage map,it concluded that the resistance gene YrV3 was located on chromosome arm 1BL.Given chromosomal location,the reaction patterns and pedigree analysis,YrV3 should be a novel gene for resistance to stripe rust in wheat.These closely linked markers should be useful in stacking genes from different sources for wheat breeding and diversification of resistance genes against stripe rust. 相似文献
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不同核桃品种光合特性比较研究 总被引:1,自引:0,他引:1
用Li-6400便携式光合作用测定系统,对香玲、鲁光、清香、西林3号、西洛3号5个核桃品种的光合生理特性进行了研究。结果表明,5个品种的净光合速率日平均值大小顺序为香玲>鲁光>清香>西林三号>西洛3号。净光合速率日变化、蒸腾速率日变化和气孔导度日变化曲线均呈单峰型和双峰型;不同品种净光合速率与蒸腾速率、气孔导度,蒸腾速率与气孔导度均呈极显著正相关(P<0.01);香玲品种核桃苗叶光补偿点、光饱和点分别为58.997、1 450μmo1·m-2·s-1。 相似文献
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对来自陕西省陇县八度林场和洛南古城林场两个油松种子园的47个全同胞家系进行苗期试验,结果表明,一年生幼苗苗高、地径、子叶长度、真叶长度、下胚轴高等性状苗期表现在家系间差异显著而在家系内差异不显著;一年生幼苗地径与苗高间存在显著相关关系,真叶长度与地径和苗高均存在显著相关关系,下胚轴高与苗高存极显著相关关系,其余性状间的相关性不显著,二年生幼苗苗高与地径间仍为显著相关关系。二年生与一年生油松幼苗的苗高间存在极显著相关关系,二年生的苗高与一年生地径间也存在显著相关关系,二年生与一年生油松幼苗地径间的相关性则不显著;各性状的家系遗传力均大于单株遗传力。家系遗传力与单株遗传力由大到小的顺序均为苗高>真叶>下胚轴>地径>子叶;初步选取了D8×G3,276×52,C16×B32,B146×K60,265×16,65×305,48×230,B69×B26,44×270,66×245,D11×G8等11个优良家系。 相似文献
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陕西银杏主要栽培品种的数量分类研究 总被引:4,自引:0,他引:4
以36个陕西银杏主要栽培品种作为分类运算单位,选用20个形态性状进行聚类分析和主成分分析。结果表明,数量分类能基本反映银杏品种间的遗传差异,与传统分类法基本吻合。Q型聚类可按照植株形态特征将36个品种分为5类,其中第1类(马铃3号、泰山3号)可作优良的叶用银杏栽培品种,第4类(陕引15号)和第3类(陕引10号、C9468、陕引2号)适合做观赏绿化用;主成分分析可将原20个性状综合成7个主成分,其累积贡献率可以达到85%以上,其中叶大小(包括叶长、叶宽、叶面积)、叶形态(包括叶形指数、叶色、叶重、叶厚)为第一、二主成分,将叶形态和叶大小作为银杏品种分类的主要分类标准是可行的。 相似文献