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981.
2000年对5%恶霉灵-甲霜灵-丙烯酸水剂防治水稻病害进行实验示范。结果表明:5%恶霉灵-甲霜灵-丙烯酸水剂药量75-125g(a.i)/ha,茎叶喷雾,对水稻穗颈瘟防治效果达90%以上,增产15%,是目前水稻田稻瘟防治理想药剂。 相似文献
982.
以黑米为材料,设计乙醇体积分数、乙醇酸碱度和浸制时间3个因素,在3个不同水平上进行黑米酒的浸制实验,分析比较了黑米酒的黄酮和色素含量,结果表明,3因素中,对黄酮含量影响效应为浸提时间>乙醇体积分数>乙醇酸碱度,而对色素含量影响效效应则为乙醇酸碱度>乙醇体积分数>浸提时间;乙醇的体积分数为40%-60%、酸碱度pH4有利于黄酮和色素的浸出及色泽的改善;3d的浸提时间可最大限度溶解黄酮物质,且对黑米色素溶解较好。 相似文献
983.
深圳股票价格指数的功率谱检验 总被引:1,自引:0,他引:1
首先对股票指数进行了非趋势化处理,接着对经过非趋化处理后的股票指数数据进行了功率谱检验,其目的在于后续计算股票指数的关联组数和李雅普诺夫指数,以便对股市进行有效的预测和研究。 相似文献
984.
Using the genomic DNAs of maize and rice as probes respectively, the homology of maize and rice genomes was assessed by genomic in situ hybridization. When rice genomic DNAs were hybridized to maize, all chromosomes displayed many multiple discrete regions, while each rice chromosome delineated a single consecutive chromosomal region after they were hybridized with maize genomic DNAs. The results indicate that the genomes of maize and rice share high homology, and confirm the proposal that maize and rice are diverged from a common ancestor. 相似文献
985.
The sterility of Pingxiang male-sterile rice (Pms), possibly derided from a spontaneous mutation in Pingxiang fertile rice (Pmf), was previously reported to be controlled by a single dominant nuclear gene. It can be restored to fertility either by a dominant epistatic gene or by higher temperature treatment at the early stage of inflorescence development. In order to tag the genic male-sterile gene, Pms, Pmf and Ce 64, a cytoplasmic male-sterile restoring line without the epistatic gene for Pms, were used to construct mapping populations. Two segregation populations, “(Pms/Ce 64) F1s (sterile plant)//Pmf ” F1 and “Pms//(Pmf/Ce 64) F1” F1, were simultaneously developed. Subsequently, the genic male- sterile gene was mapped between a simple sequence length polymorphism marker, RM228, and a restriction fragment length polymorphism marker, G2155, with distances of 14.9 and 2.6 cM, respectively. The tagged dominant genic male-sterile gene is temporarily designated Ms-p. 相似文献
986.
YU Jun HU Songnian WANG Jun LI Songgang WONG Ka-Shu Gane LIU Bin DENG Yajun DAI Li YUAN Longping YANG Huanming 《科学通报(英文版)》2001,46(23):1937-1942
The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development,
and evolution, as well as information on many beneficial phenotypes of economic significance. Using a “whole genome shotgun”
approach, we have produced a draft rice genome sequence ofOryza sativa ssp.indica, the major crop rice subspecies in China and many other regions of Asia. The draft genome sequence is constructed from over
4.3 million successful sequencing traces with an accumulative total length of 2214.9 Mb. The initial assembly of the non-redundant
sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb
from anindica variant cultivar93-11, giving an estimated coverage of 95.29% of the rice genome with an average base accuracy of higher than 99%. The coverage
of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEMBLER, a custom-designed
software package used for the initial assembly, were verified rigorously by comparisons against finished BAC clone sequences
from bothindica andjapanica strains, available from the public databases. Over all, 96.3% of full-length cDNAs, 96.4% of STS, STR, RFLP markers, 94.0%
of ESTs and 94.9% unigene clusters were identified from the draft sequence. Our preliminary analysis on the data set shows
that our rice draft sequence is consistent with the comman standard accepted by the genome sequencing community. The unconditional
release of the draft to the public also undoubtedly provides a fundamental resource to the international scientific communities
to facilitate genomic and genetic studies on rice biology.
These authors contributed equally to this work. 相似文献
987.
Bojun Ma Wenming Wang Junhuang Zou Guoqing Liu Jin Fang Lihuang Zhu Wenxue Zhai 《科学通报(英文版)》2001,46(2):125-128
The homozygous restorer lines with a single copy of the transgene Xa21 have been obtained from the progenies of transgenic Minghui63 and Yanhui559 plants through PCR marker-assisted selection and test cross. These homozygous transgenic restorer lines can be used to breed hybrid rice with high resistance to bacterial leaf blight. 相似文献
988.
普通野生稻中NBS同源序列的克隆和分析 总被引:9,自引:0,他引:9
已知的植物抗病基因大多数具有核苷结合位点(NBS)和富含亮氨酸重复(LRR)。根据NBS的保守区设计引物,应用聚合酶链式反应(PCR),从普通野生稻基因组中克隆了4个不同的NBS同源序列(OSNBA1-OSNBA4)。同源性比较显示它们均与非TIR类的NBS序列相似,其中,OSNBA1与双子叶植物拟南芥的RPS2基因更接近;OSNBA2-OSNBA4与单子叶植物水稻的XA1、RPR1基因更相似。 相似文献
989.
太湖地区水稻节水灌溉与氮素淋失 总被引:16,自引:1,他引:15
通过田间试验探讨有效的农田氮素水体污染防治途径。研究表明,节水灌溉(湿润灌溉)情况下渗漏水中总氮浓度、氮素渗漏量、氮素渗漏损失代价均随着施氮量的增加而增加,渗漏水中3种形态的氮素(硝态氮、铵态氮和有机氮)以硝态氮为主,铵态氮和有机氮占的比例较低;和常规灌溉相比,相同施氮处理(264.75kg/hm^2)采用节水灌溉时稻谷增产4.1%,氮肥当季利用率提高3%、氮素渗漏量下降8.9kg/hm^2,水稻节水灌溉是当前降低太湖地区水体氮素污染行之有效的重要措施之一。 相似文献
990.
针对传统PCA(主元分析)股票价格预测方法在非线性过程应用中存在的缺点,本文提出了一种基于RBF神经网络的非线性PCA(NLPCA)方法,不仅提取了高维原始数据的线性信息还能提取非线性信息.在此基础上进一步提出了样本中误差的检测方法,仿真试验表明它能有效地减小误差点对网络训练精度的影响,大大增强了股票价格预测的准确性. 相似文献