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Characterization of root architecture in an applied core collection for phosphorus efficiency of soybean germplasm 总被引:9,自引:0,他引:9
ZHAOJing FUJiabing LIAOHong HEYong NIANHai HUYueming QIULinjuan DONGYinsan YANXiaolong 《科学通报(英文版)》2004,49(15):1611-1620
In the present study, we constructed an “applied core collection“ for phosphorus (P) efficiency of soybean germplasm using a GIS-assisted approach. Systematic characterization and comparative analysis of root architecture were conducted to evaluate the relationship between root architecture and P efficiency and its possible evolutionary pattern. Our results found that: i) root architecture was closely related to P efficiency in soybean. Shallow root architecture had better spatial configuration in the P-rich cultivated soil layer hence higher P efficiency and soybean yield; ii) there was a possible co-evolutionary pattern among shoot type, root architecture and P efficiency. The bush cultivated soybean had a shallow root architecture and high P efficiency, the climbing wild soybean had a deep root architecture and low P efficiency, while the root architecture and P efficiency of semi-wild soybean were intermediate between cultivated and wild soybean; iii) P availability regulated root architecture. Soybean roots became shallower with P addition to the topsoil, indicating that the co-evolutionary relationship between root architecture and P efficiency might be attributed to the long-term effects of topsoil fertilization. Our results could provide important theoretical basis for improving soybean root traits and P efficiency. 相似文献
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近年来,复合材料逐渐被广泛应用于输电杆塔横担结构中,为了研究复合材料横担的极限承载力,本文对35kV复合材料横担进行了极限承载能力试验,得到各个测点在不同横向载荷作用下的位移和应变;建立该复合横担的有限元模型,通过计算得到相应测点的位移和应变结果;结合试验与仿真结果,分析了复合横担在横向载荷作用下的变形规律;通过分析根部压接对复合横担极限承载能力的影响,提出了一种新的法兰与复合材料芯棒的连接方式。研究结果表明:当横向载荷达到16.91kN时,芯棒上表面与法兰开始脱离,当横向载荷达到29.81kN时,复合横担根部发生失效;结合仿真与试验结果,证实了复合横担根部压接脱离是决定复合横担极限承载力的重要因素之一;提出的新型根部连接方式可以有效提升复合材料横担的极限承载能力。 相似文献
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<正>在常规超声波探伤中,对检测缺陷进行定性分析存在一定难度。比如,焊缝探伤中未焊透、根部内凹、根部错边等情况不易确定,目前国外的相关标准也都没有提及缺陷的定性分析。但是在实际工作中,除了对危害性缺陷进行定量分析以外,结合 相似文献
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在常规超声波探伤中,对检测缺陷进行定性分析存在一定难度。比如,焊缝探伤中未焊透、根部内凹、根部错边等情况不易确定,目前国外的相关标准也都没有提及缺陷的定性分析。 相似文献
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1.缺氛障碍。葡萄缺氮时,叶片失绿黄化,叶小而薄;新梢生长缓慢,枝蔓细弱,节间短;果穗松散,成熟不齐,产量降低。发现缺氛,应及时在根部追施适量氛肥,也可结合根部施肥,用0.5%尿素溶液进行叶面喷施。 相似文献
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连,轮作大豆土壤微生物生态分布特征与大豆根部病… 总被引:14,自引:0,他引:14
本研究在东北黑土大豆主产区进行,四年定位试验,分别设置大豆轮作、连作(连一、连三)、迎茬及休闲地五个处理区。重点分析了大豆生育期间不同茬口、土壤微生物组成及密度,不同茬口,大豆根腐病、大豆孢囊线虫病和大豆根潜蝇的发生程度及其对大豆产量的影响。 相似文献
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四、施肥过于集中 生产中,幼树多因施肥过于集中而造成根死、树干纵枯现象.成年树发生肥害后,常导致根系局部烧坏褐变,引发根腐病等根部病害. 相似文献