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991.
过去20多年来,随着板式家具的高速发展,消费了大量中密度纤维板,带动我国中密度纤维板业的发展。不但在家具领域,而且在装修和包装等行业里对中/高密度纤维板的需求量也不断增加。在国际市场上,我国中密度纤维板出口数量也不断增长,2012年产量达到5023万m3。近10多年来,中  相似文献   
992.
介绍了戴云山国家级自然保护区资源现状,从自然环境、生物资源的多样性、生态系统的典型性、科普教育、科学及经济社会等方面分析其保护价值,并阐明了加快戴云山国家级自然保护区建设的重要意义。  相似文献   
993.
Effects of light, macronutrients strength of Murashige and Skoog (MS) (1962), and sucrose in the culture medium on spore germination and gametophyte development of the endangered fern Adiantum reniforme var. sinense were investigated. The presence of light was found to be essential for both spore germination and gametophyte growth. Moreover, a medium consisting of 1/4 MS with 15 g/l sucrose was optimal for spore germination and early gametophyte development; whereas, MS medium with 30 g/l sucrose was optimal for further gametophyte development. Increasing amounts of sucrose (45–60 g/l) in the medium delayed gametophyte growth and development. Additionally, sporophyte formation and early growth of gametophytes in a medium consisting of clay and peat (v/v = 1:2) was higher than those in a medium consisting of pure river sand. These findings indicated that requirements for nutrients for spore germination and early gametophyte development of A. reniforme var. sinese were relatively low, but these increased with further gametophyte development, formation and growth of sporophytes.  相似文献   
994.
Duan  W. J.  Zhang  X. Q.  Yang  T. Z.  Dou  X. W.  Chen  T. G.  Li  S. J.  Jiang  S. J.  Huang  Y. J.  Yin  Q. Y. 《植物病害和植物保护杂志》2010,117(3):112-116
Journal of Plant Diseases and Protection - Alternaria alternata (Fries) Keissler is a facultative parasitic fungus which causes brown spot disease of senescing tobacco (Nicotiana tabacum L.)...  相似文献   
995.
996.
X. K. Zhang    L. Liu    Z. H. He    D. J. Sun    X. Y. He    Z. H. Xu    P. P. Zhang    F. Chen    X. C. Xia 《Plant Breeding》2008,127(2):109-115
Wheat quality properties are genetically determined by the compositions of high and low molecular weight glutenin subunits, grain hardness, polyphenol oxidase (PPO) activity and starch viscosity. Two multiplex PCR assays were developed and validated using 70 cultivars and advanced lines from Chinese autumn‐sown wheat regions. Multiplex PCR I includes molecular markers for genes/loci ω‐secalin, Glu‐B1‐2a (By8), Glu‐D1‐1d (Dx5), Glu‐A3d, Glu‐B3 (for non‐1B·1R type) and Pinb‐D1b targeting improved gluten parameters and pan bread quality. Multiplex PCR II comprises markers for genes/loci Ppo‐A1, Ppo‐D1 and Wx‐B1b targeting improved noodle quality. The results were consistent with those achieved by SDS‐PAGE and RP‐HPLC, indicating that the two multiplex assays were highly effective, with good repeatability and low costs enabling their use in wheat breeding programmes. In total, nine alleles (subunits) at locus Glu‐B1, four at Glu‐D1 and five at Glu‐A3 locus were identified, and the alleles (subunits) Glu‐B1b (7 + 8), Glu‐B1c (7 + 9), Glu‐D1a (2 + 12), Glu‐D1d (5 + 10), Glu‐A3a, Glu‐A3c and Glu‐A3d were most frequently present in the cultivars and lines tested. The 1B·1R translocation was present in 28 (40.0%) lines, whereas the Wx‐B1 null allele for better noodle quality was present in only seven (10.0%) cultivars and advanced lines, and 37 (52.9%) lines had Pinb‐D1b associated with hard grains. The allele Ppo‐A1b on chromosome 2AL associated with lower PPO activity was present in 38 (54.3%) genotypes, whereas the less effective allele Ppo‐D1a on chromosome 2DL, also associated with low PPO activity was present in 45 (64.3%) of genotypes. These two multiplex PCR assays should be effective in marker assisted selection targeting improved pan bread‐making and noodle qualities.  相似文献   
997.
运用灰色关联度分析法对31个油茶无性系进行综合评判,较全面地分析了各品种的综合表现及各性状的相互关系。结果表明,各油茶无性系的加权关联度大小顺序依次为:XLC48,XLC36,XLC55,XLC41,XLC42,XLC59,XLC58,XLC43,XLC44,XLC56,XLC61,XLC33,XLC46,XLC50,XLC37,XLC31,XLC54,XLC57,XLC45,XLC49,XLC40,XLC38,XLC47,XLC39,XLC35,XLC51,XLC60,XLC52,XLC34,XLC53,XLC32;各经济性状与产油量关系密切程度的顺序依次为:鲜果出籽率,干籽含油率,抗病性,果形指数,总叶片数,单果重,冠幅面积,单株产果量,为今后油茶定向育种提供了理论依据。  相似文献   
998.
Cotton yield improvement is vital to fulfill rising global demands. The identification of major quantitative trait loci (QTL) for yield components was helpful in molecular marker-assisted selection (MAS) to improve cotton yield. We previously identified a densely populated QTL region for fiber qualities and yield components on chromosome D8 (Chro.D8) of Upland cotton from a (7235 × TM-1)RIL. In the present study, to fine-map yield component QTLs, we chose three overlapped recombinant inbred lines (RILs) with different intervals included the yield component QTLs, and backcrossed each line with TM-1 to develop three large sized mapping populations. Phenotypic data for yield components were collected in Nanjing (JES/NAU) and Xinjiang (BES/XJ) in 2006 and 2007. Three simple sequence repeat (SSR) genetic linkage maps on chro.D8 were constructed using 907 individuals in (7TR-133 × TM-1)F2 (Pop A), 670 in (7TR-132 × TM-1)F2 (Pop B), and 940 in (7TR-214 × TM-1)F2 (Pop C). Three stable QTLs for boll size, two for lint percentage and one for boll number per plant,were detected on chro.D8 following analysis of three RIL backcrossed F2/F2:3 progeny at JES/NAU and BES/XJ although their cultivation practices differ greatly between these two cotton-growing regions. One QTL for boll number per plant exhibited a phenotypic variance (PV) of 5.6–10.1%, three QTLs for boll size exhibited 15.0–35.5% PV and two lint percentage QTLs exhibited 10.9–19.3% PV. Negative correlation between lint yield and fiber strength was confirmed.  相似文献   
999.
试验采取盆栽,三次重复,以2个不同青蒿为材料,在遮阴和正常两个条件下,利用生物性状检测青蒿的遮阴性能。结果表明,遮阴条件下,青蒿地上部干重、地下部干重、株高、叶面积、叶绿素含量、类胡萝卜素含量和青蒿素含量均减少,经过方差分析,2个青蒿材料各项指标遮阴和正常两个条件下差异显著, 青蒿叶片青蒿素与地上部干重、叶绿素含量和类胡萝卜素达1%显著相关。  相似文献   
1000.
陈国文  李丽 《粮食储藏》2003,32(4):44-46
本文就美国齐富24—13钢板仓安装的诸多问题进行了探讨,表明了其具有广泛的实用价值。  相似文献   
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