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901.
902.
PENG Yuan-ying PENG Zheng-song SONG Hui-xing XU Jia-shao 《中国农业科学(英文版)》2006,5(8):579-586
Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous chromosomes on photosynthesis using the substitution series as materials. In this research, Triticum aestivum cv. Chinese Spring-Lophopyrum elongatum (Host) A.Loeve disomic substitution series were used as materials and flag leaves as the measuring position. And the CI-310 Portable Photosynthesis System made by CID Co. in USA was used to measure the net rate of photosynthesis of flag leaves in different developing stages and also to correlate photosynthesis with yield. Results showed that, out of the whole developing stages, at the anthesis stage the line of DS2Ee (2A) had the highest photosynthetic rate, therefore it could be used in improving process of the character of kernel number. The flag leaves of DS4Ee (4A, 4B, 4D) lines demonstrated certain high net photosynthetic rate from heading to grain filling stage, so it is valuable in the researh of promoting the yield index like 1 000-grain weight through improvement of the photosynthetic rate at grain filling stage. 相似文献
903.
904.
Ji-Rui Wang Ze-Hong Yan Yu-Ming Wei Eviatar Nevo Bernard R. Baum You-Liang Zheng 《Journal of Cereal Science》2006,43(3):360-368
Alpha-amylase inhibitors are attractive candidates for the control of seed weevils as these insects are highly dependent on starch as an energy source. For weevil control, alpha-amylase inhibitors and their genes could be used to genetically engineer weevil resistant seeds. Thirty genes encoding dimeric alpha-amylase inhibitors were isolated from Triticum aestivum L. ‘Chinese Spring’ and characterized by nucleotide and amino acid sequence analysis. Eleven representative alpha-amylase inhibitor genes were identified, and the deduced amino acid sequences of these genes were of high coherence (95.1%). These inhibitors and others obtained from the wheat EST database were clustered into three groups, the genes from ‘Chinese Spring’ were present in each group. Specific primer sets were designed for each group, based on the SNPs of these genes, and the chromosome locations of each group of inhibitor genes investigated by amplification of the ‘Chinese Spring’ ditelosomic lines. There were two and one groups of inhibitor genes on chromosomes 3BS and 3DS, respectively, whereas no group of inhibitor genes was found on chromosome 3AS. Thus, the primer set for each group of inhibitor genes was genome allele-specific. The two known inhibitors, 0.53 and 0.19, were located on chromosomes 3BS and 3DS, respectively. The validity of the three genome allele-specific primer sets was confirmed by amplifications in 15 accessions of Triticum urartu, Triticum monococcum, Aegilops tauschii and Triticum dicoccoides. These results gave further support at the molecular level, that the 24 kDa dimeric alpha-amylase inhibitors in cultivated wheat are encoded by a multigene family. 相似文献
905.
利用分子标记定位水稻芽期耐冷性基因 总被引:30,自引:4,他引:30
利用籼稻品种南京11和粳稻品种巴利拉的F1花药进行组织培养,获得67个加倍单倍体植株(Doubled haploid, DH)。 以该群体构建了一张包含131个RFLP标记的水稻分子图谱。 以芽期的死苗率为指标, 评定亲本及各 DH系在低温(4~5℃)条件下的耐冷性。结果表明:死苗率在DH群体中呈双峰连续分布, 表明芽期耐冷性是由主基因控制的数量性状。将死苗率作为数量性状进行QTL的区间作图分析, 发现在第7染色体上G379b-RG4区间存在有与耐冷性有关的基因(Cts7) 。 相似文献
906.
为了研究福建三明地区火烧迹地杉木人工林地的土壤速效养分变化,采用调查取样和室内分析相结合的方法,对上、中和下3个坡位的土壤,分别在火烧前、火烧2个月、1年和2年后,分析速效性养分质量分数的变化.结果表明:硝态氮质量分数在火烧2个月和1年后相比火烧前均有上升趋势,且火烧1年内,上坡位较中坡位和下坡位的硝态氮质量分数要低,在火烧2年后硝态氮质量分数略低于火烧前水平,但未达到显著差异;铵态氮质量分数与硝态氮质量分数的变化趋势相反,在火烧的第1年内持续下降,但在火烧第2年后显著升高;不同时间的速效磷质量分数,在不同坡位间无显著差异,火烧的第1年内,其质量分数变化不明显,在火烧2年后显著升高,这可能是土壤矿化速度加快造成的结果;无机氮/速效磷比值在火烧2年后显著降低,速效磷质量分数剧增是影响其比值的主要因素.火烧在短期内,加快了土壤速效性养分循环,但要注意可能造成氮素从森林生态系统中流失.研究以期为火烧对土壤养分的长期影响提供数据基础,为森林生态系统火烧迹地的人工林经营,提供科学的理论依据. 相似文献
907.
基于地理信息系统的农村电网规划 总被引:3,自引:0,他引:3
针对目前农村电网规划难以满足规划人员实用要求的现状,提出应用地理信息系统(GIS)技术改进农村电网规划的设想,并结合珠海斗门县电网进行了试验性的研究。利用VB5.0和GIS软件进行了农村电网规划应用程序的开发,实现了农村电网的变电站选址以及路径优化。研究结果表明,借助GIS无需复杂的计算便可实现农村电网的规划,且规划过程更具交互性,规划结果更具直观性,方案调整更具灵活性。GIS可作为农村电网规划人员的得力工具。 相似文献
908.
909.
TIBL-1RS wheat-rye translocation cultivars utilized in wheat programmes worldwide carry powdery mildew resistance gene Pm8. Cultivar‘Amigo’possesses resistance gene Pm17 on its TIAL-1RS translocated chromosome. To be able to use Pm17efficiently in breeding programmes, this gene was transferred to a TIBL-1RS translocation in line Helami-105, and allelism between Pm8 and Pm17was studied. The progenies of the hybrids in the F2 generation and F3 families provided evidence that the two genes are allelic. Genetic studies using monosomic analyses confirmed that in cultivar‘Amigo', Pm17 and leaf rust resistance gene Lr24 are located on a translocated chromosome involving 1 A and 1B, respectively. 相似文献
910.
农业跨区域投资对于促进区域优势互补,实现乡村产业振兴具有重要意义。基于浙江省跨区域农业投资项目库,运用计量经济模型从宏观上解析农业跨区域投资的区位影响因素,结合微观调查法从投资主体视角分析其区位决策机制。研究表明:浙江农业跨区域投资总体上呈现东高西低、由东部向西部递减的区位特征,且主要集中在周边省(市)和农业大省;耕地资源条件、农业发展基础、与产业类型相匹配的自然环境条件以及与产品消费市场之间的距离是农业跨区域投资区位选择的主要影响因素;在跨区域投资区位决策中,农业投资者除了关注土地、劳动力、农业基础设施条件、交通运输条件、优惠政策等经济因素外,还较关注社会治安、民风状况、政府部门工作效率、领导重视程度等社会政治因素。据此,提出了农业“精准招商”策略和优化营商环境的建议。 相似文献