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Correlation Analysis Between Yield Components and Yield Per Plant of Double-low Hybrid Rapeseed 被引量:1
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作者 张锦芳 周贤琼 +2 位作者 蒲晓斌 李浩杰 蒋梁材 《Agricultural Science & Technology》 CAS 2008年第6期82-83,117,共3页
[Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new doubl... [Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new double-low hybrid rapeseed variety. [Method]The yield components and yield per plant of two cross combination of double-low hybrid rapeseed (B02, D04) and Shuza 6 were correlatively analyzed and compared, besides, the path analysis was also carried on to them. [Result] Among B02, D04 and Shuza No.6, effective pod number per plant and seeds per silique, seeds per pod and 1 000-grain weight were all negative correlation. In high yield hybrid, pod number per plant, seeds per pod had more impaction on yield per plant than 1 000-grain weight and the difference was at 0.01 significant level. In the control variety Shuza No.6, the impactions of pod number per plant and seeds per pod on yield per plant were bigger than that of 1 000-grain weight on yield per plant, however, the difference was not significant. [Conclusion] The improvement of effective pod number per plant was an important aim of breeding work of double low rapeseed breeding in Sichuan ecological region. 展开更多
关键词 Double low rapeseed yield components yield per plant Correlation analysis Path analysis
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Research of an Appropriate Sowing Quantity of Double-cropping Machine-transplanted Rice in Low and Medium Yielding District of Southern Jiangxi Province
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作者 钟珺 胡启锋 +4 位作者 李云 黎为兵 连垚 张朝阳 虞新华 《Agricultural Science & Technology》 CAS 2016年第3期526-529,543,共5页
[Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five differ... [Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five different seeding quantities treatments, and compared with conventional seedling treatment, and the appropriate seeding quantities of double season machine-transplanted rice in middle and lowyielding district of southern Jiangxi Province was discussed. [Result] The yields were highest when the seeding quantity was 70 g per tray of early rice by mechanical transplanting and 60 g per tray of late rice. The yield of early rice by mechanical transplanting showed significantly positive correlation with the number of productive ear and the number of seed per ear, and late rice yield showed significant correlation with the number of productive ear by mechanical transplanting. It is key for improving high yields by guaranteeing the number of productive ear. [Conclusion] The issue of proper sowing quantity should be taken into consideration for double-cropping rice in the region, which is crucial for high yields. 展开更多
关键词 Sowing quantity Double-cropping rice Machine-transplanted Rice low and medium yielding farmlands
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Effects of Low Light on Agronomic and Physiological Characteristics of Rice Including Grain Yield and Quality 被引量:20
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作者 LIU Qi-hua WU Xiu +2 位作者 CHEN Bo-cong MA Jia-qing GAO Jie 《Rice science》 SCIE 2014年第5期243-251,共9页
Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling st... Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components (milling and appearance as well as cooking, eating and nutritional qualities) under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments. 展开更多
关键词 grain quality grain yield physiological characteristic RICE low light agronomic characteristic
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Differential Expression of Iron Deficiency Responsive Rice Genes under Low Phosphorus and Iron Toxicity Conditions and Association of OsIRO3 with Yield in Acidic Soils 被引量:2
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作者 Ernieca Lyngdoh NONGBRI Sudip DAS +3 位作者 Karma Landup BHUTIA Aleimo G.MOMIN Mayank RAI Wricha TYAGI 《Rice science》 SCIE CSCD 2023年第1期58-69,共12页
With the hypothesis that iron(Fe) deficiency responsive genes may play a role in Fe toxicity conditions,we studied five such genes OsNAS1,OsNAS3,OsIRO2,OsIRO3 and OsYSL16 across six contrasting rice genotypes for expr... With the hypothesis that iron(Fe) deficiency responsive genes may play a role in Fe toxicity conditions,we studied five such genes OsNAS1,OsNAS3,OsIRO2,OsIRO3 and OsYSL16 across six contrasting rice genotypes for expression under high Fe and low phosphorus(P) conditions,and sequence polymorphism.Genotypes Sahbhagi Dhan,Chakhao Poirieton and Shasharang were high yielders with no bronzing symptom visible under Fe toxic field conditions,and BAM350 and BAM811 were low yielders but did not show bronzing symptoms.Hydroponic screening revealed that the number of crown roots and root length can be traits for consideration for identifying Fe toxicity tolerance in rice genotypes.Fe contents in rice roots and shoots of a high-yielding genotype KMR3 showing leaf bronzing were significantly high.In response to 24 h high Fe stress,the expression levels of OsNAS3 were up-regulated in all genotypes except KMR3.In response to 48 h high Fe stress,the expression levels of OsNAS1 were3-fold higher in tolerant Shasharang,whereas in KMR3,it was significantly down-regulated.Even in response to 7 d excess Fe stress,the transcript abundances of OsIRO2 and OsNAS3 were contrasting in genotypes Shasharang and KMR3.This suggested that the reported Fe deficiency genes had a role in Fe toxicity and that in genotype KMR3 under excess Fe stress,there was disruption of metal homeostasis.Under the 48 h low P conditions,OsIRO2 and OsYSL16 were significantly up-regulated in Fe tolerant genotype Shasharang and in low P tolerant genotype Chakhao Poirieton,respectively.In silico sequence analysis across 3 024 rice genotypes revealed polymorphism for 4 genes.Sequencing across OsIRO3and OsNAS3 revealed nucleotide polymorphism between tolerant and susceptible genotypes for Fe toxicity.Non-synonymous single nucleotide polymorphisms and insertion/deletions(InDels) differing in tolerant and susceptible genotypes were identified.A marker targeting 25-bp InDel in OsIRO3,when run on a diverse panel of 43 rice genotypes and a biparental population,was associated with superior performance for yield under acidic lowland field conditions.This study highlights the potential of one of the vital genes involved in Fe homeostasis as a genic target for improving rice yield in acidic soils. 展开更多
关键词 acidic soil low phosphorus iron toxicity OsNAS1 OsIRO3 RICE yield
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A Novel Multiphase Stainless Steel with Ultra-Low Yield Ratio and High Ductility 被引量:1
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作者 Menghao Liu Cuiwei Du +1 位作者 Yuewu Li Xiaogang Li 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第10期1777-1784,共8页
This study focuses on developing a novel multiphase stainless steel with enhanced ductility and an ultralow yield ratio achieved through solid-solution treatment.The steel exhibits remarkable mechanical properties:a t... This study focuses on developing a novel multiphase stainless steel with enhanced ductility and an ultralow yield ratio achieved through solid-solution treatment.The steel exhibits remarkable mechanical properties:a tensile strength of approximately 1114 MPa,an ultralow yield ratio of 0.36,exceptional uniform elongation of approximately 17.48%,and total elongation of approximately 21.73%.The remarkable ductility of the steel can be attributed to the transformation-induced plasticity(TRIP)effect observed in the retained austenite,while its exceptional strength results from the combined effects of TRIP and the martensite phase. 展开更多
关键词 Stainless steels Metastable phases low yield ratio Martensitic phase transformation
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Potential promoted productivity and spatial patterns of medium-and low-yield cropland land in China 被引量:9
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作者 闫慧敏 冀咏赞 +3 位作者 刘纪远 刘芳 胡云锋 匡文慧 《Journal of Geographical Sciences》 SCIE CSCD 2016年第3期259-271,共13页
With a continuously increasing population and better food consumption levels, im- proving the efficiency of arable land use and increasing its productivity have become funda- mental strategies to meet the growing food... With a continuously increasing population and better food consumption levels, im- proving the efficiency of arable land use and increasing its productivity have become funda- mental strategies to meet the growing food security needs in China. A spatial distribution map of medium- and low-yield cropland is necessary to implement plans for cropland improvement In this study, we developed a new method to identify high-, medium-, and low-yield cropland from Moderate Resolution Imaging Spectroradiometer (MODIS) data at a spatial resolution of 500 m. The method could be used to reflect the regional heterogeneity of cropland productiv- ity because the classification standard was based on the regionalization of cropping systems in China. The results showed that the proportion of high-, medium-, and low-yield cropland in China was 21%, 39%, and 40%, respectively. About 75% of the low-yield cropland was lo- cated in hilly and mountainous areas, and about 53% of the high-yield cropland was located in plain areas. The five provinces with the largest area of high-yield cropland were all located in the Huang-Huai-Hai region, and the area amounted to 42% of the national high-yield cropland area. Meanwhile, the proportion of high-yield cropland was lower than 15% in Hei- Iongjiang, Sichuan, and Inner Mongolia, which had the largest area allocated to cropland in China. If all the medium-yield cropland could be improved to the productive level of high-yield cropland and the low-yield cropland could be improved to the level of medium-yield cropland, the total productivity of the land would increase 19% and 24%, respectively. 展开更多
关键词 food security light use efficiency model cropland productivity high- medium- and low-yield crop-land potential productivity
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The Impact of Varied Fertilizers on the Yield and Quality of Panicum miliaceum under Low Nitrogen Conditions
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作者 Mengyao Wang Jiao Mao +6 位作者 Yuanmeng Xu Shu Wang Yuhan Liu Jiangling Ren Sichen Liu Zhijun Qiao Xiaoning Cao 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第10期2629-2644,共16页
To clarify the response characteristics of broomcorn millet yield and quality to various fertilizers under low nitrogen conditions,the present study investigated the effects of different fertilization treatments,inclu... To clarify the response characteristics of broomcorn millet yield and quality to various fertilizers under low nitrogen conditions,the present study investigated the effects of different fertilization treatments,including no fertilization(HCK,CCK),urea(HF1,CF1),phosphate fertilizer(HF2,CF2),compound fertilizer(HF3,CF3),and organic fertilizer(HF4,CF4),on the agronomic traits,quality,and starch pasting properties of proso millet.As experimental materials,non-waxy proso millet(Hequ red proso millet,denoted as HQH)and waxy proso millet(Chishu 1,denoted as CS1)were utilized.The results showed that under low nitrogen conditions,urea treatment(HF1)significantly increased plant height and yield,and phosphate fertilizer treatment(HF2)significantly increased thousand-grain weight(TW).For waxy proso millet Chishu NO.1(CS1),urea treatment(CF1)significantly increased yield,phosphate fertilizer treatment(CF2)significantly influenced the height of the plants,and compound fertilizer treatment(CF3)significantly increased thousand-grain weight.In terms of quality,phosphate fertilizer treatment(CF2)and organic fertilizer treatment(CF4)resulted in a substantial augmentation of both the total starch content and amylose content of waxy proso millet Chishu NO.1(CS1),respectively,and organic fertilizer treatment(HF4,CF4)resulted in a notable enhancement of the protein content of proso millet.Organic fertilizer treatment(HF4)increased peak viscosity(PV),hot viscosity(HV),setback viscosity(SV),final viscosity(FV),breakdown viscosity(BV),pasting time(PTim),and pasting temperature(PTemp)of non-waxy proso millet.Phosphate fertilizer treatment(CF2)increased the peak viscosity(PV),hot viscosity(HV),breakdown viscosity(BV),final viscosity(FV),pasting time(PTim),and pasting temperature(PTemp)of waxy proso millet.Organic fertilizer treatment(HF4)and phosphate fertilizer treatment(CF2)under low nitrogen were the most effective in improving the comprehensive quality of non-waxy and waxy proso millet,respectively.The findings of our research elucidated the impacts of various fertilizers on the productivity and quality of non-waxy and waxy proso millet in nitrogen-deficient environments.Furthermore,this research offered a conceptual underpinning for attaining enhanced cultivation outcomes,encompassing both improved yield and quality,of proso millet in drought-prone regions. 展开更多
关键词 Proso millet low nitrogen yield QUALITY
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Low cycle fatigue estimation of low yield point steel
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作者 LI Chen DING Fulian 《Baosteel Technical Research》 CAS 2010年第S1期123-123,共1页
With the development of technology for earthquake resistant,the research of the low yield point(LYP)steel which used for the fabrication of energy dissipation damper were paid more and more attention.The common studie... With the development of technology for earthquake resistant,the research of the low yield point(LYP)steel which used for the fabrication of energy dissipation damper were paid more and more attention.The common studies of the low yield point steel is mainly about the performance with constant amplitude and constant frequency.The low cycle fatigue properties of low yield piont steel were studied by series of test with continuous varying amplitude and varying frequency with the materials testing system by us.The test results showed that low yield point steel of Baosteel have excellent low cycle fatigue properties,which meet the requirement for steel used for the fabrication of energy dissipation damper completely.The low cycle fatigue performance of low yield point steel of Baosteel mainly depended on the amplitude in test.And the effect of varying frequency for the low yield point steel was more less than varying amplitude. 展开更多
关键词 low cycle fatigue low yield point steel continuous varying amplitude and varying frequency high strain
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A New Type of Multielements-Doped,Carbon-based Materials Characterized by High-thermoconductiv-ity,Low Chemical Sputtering,Low RES Yield and Exposure to Plasma
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作者 许增裕 刘翔 +4 位作者 谌继明 王明旭 宋进仁 翟更太 李承新 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第3期1311-1317,共7页
Low-Z materials, such as carbon-based materials and Be, are major plasma-facing material (PFM) for current, even in future fusion devices. In this paper, a new type of multielement-doped carbon-based materials develop... Low-Z materials, such as carbon-based materials and Be, are major plasma-facing material (PFM) for current, even in future fusion devices. In this paper, a new type of multielement-doped carbon-based materials developed are presented along with experimental re-sults of their properties. The results indicate a decrease in chemical sputtering yield by one order of magnitude, a decrease in both thermal shock resistance and radiation-enhanced sublimation, an evidently lower temperature desorption spectrum, and combined properties of exposing to plasma. 展开更多
关键词 than GBS RES A New Type of Multielements-Doped Carbon-based Materials Characterized by High-thermoconductiv-ity low Chemical Sputtering low RES yield and Exposure to Plasma
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Actuality and Improvement Measures of Mediumand Low-yielding Farmland in Liaoning Province
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作者 Song Dan 《Meteorological and Environmental Research》 CAS 2015年第10期30-33,共4页
In order to improve the quality of cultivated land in Liaoning Province in the light of local conditions, medium- and low-yielding farmland in Liaoning Province are divided into various zones according to characterist... In order to improve the quality of cultivated land in Liaoning Province in the light of local conditions, medium- and low-yielding farmland in Liaoning Province are divided into various zones according to characteristics of the terrain, and the practical and feasible improvement measures are put forward based on the current situation and main existing problems in the medium- and low-yielding farmland in different areas, 展开更多
关键词 Medium- and low-yielding farmland Current situation Improvement measures China
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The Type of Low-yielding Fields,Using Direction and Land Fertility Building Measures in Suiping County
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作者 Jiuyi HU 《Asian Agricultural Research》 2014年第11期81-82,86,共3页
Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,s... Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,soil management,and soil nutrients concerning various types of low-yielding fields in the county. In accordance with the dominant soil constraint factors and main direction of improvement,the lowyielding fields in the county are divided into four types: irrigation improvement type,waterlogging drainage type,barren soil fertilization and barrier layer type. Finally this paper offers specific guidance on the construction of arable land. 展开更多
关键词 TYPE of low-yielding FIELDS USING direction LAND f
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Screening cotton cultivars for low-phosphorus tolerance:a comparison of hydroponic and field methods
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作者 SUN Miao DONG Helin +5 位作者 HAN Huimin FENG Weina SHAO Jingjing HUO Feichao LI Pengcheng ZHENG Cangsong 《Journal of Cotton Research》 2025年第1期89-101,共13页
Background Soil available phosphorus(AP)deficiency significantly limits cotton production,particularly in arid and saline-alkaline regions.Screening cotton cultivars for low phosphorus(P)tolerance is crucial for the s... Background Soil available phosphorus(AP)deficiency significantly limits cotton production,particularly in arid and saline-alkaline regions.Screening cotton cultivars for low phosphorus(P)tolerance is crucial for the sustainable development of cotton production.However,the effect of different growth media on the screening outcomes remains unclear.To address this,we evaluated the low P tolerance of 25 cotton cultivars through hydroponic culture at two P levels(0.01 and 0.5 mmol·L^(-1) KH_(2)PO_(4))in 2018 and field culture with two P rates(0 and 90 kg·hm^(-2),in P2O5)in 2019.Results In the hydroponic experiments,principal component analysis(PCA)showed that shoot dry weight(SDW)and P utilization efficiency in shoots(PUES)of cotton seedlings explained over 45%of the genetic variation in P nutri-tion.Cotton cultivars were subjected to comprehensive cluster analysis,utilizing agronomic traits(SDW and PUES)during the seedling stage(hydroponic)and yield and fiber quality traits during the mature stage(in field).These cultivars were grouped into four clusters:resistant,moderately resistant,moderately sensitive,and sensitive.In low P conditions(0.01 mmol·L^(-1) KH_(2)PO_(4) and 4.5 mg·kg^(-1) AP),the low-P-resistant cluster showed significantly smaller reduc-tions in SDW(54%),seed cotton yield(3%),lint yield(-2%),fiber length(-1)%),and fiber strength(-3%)compared with the low-P-sensitive cluster(75%,13%,17%,7%,and 9%,respectively).The increase in PUES(299%)in the resist-ant cluster was also significantly higher than in the sensitive cluster(131%).Four of the eight low-P-tolerant cotton cultivars identified in the field and six in the hydroponic screening overlapped in both screenings.Two cultivars overlapped in both screening in the low-P-sensitive cluster.Conclusion Based on the screenings from both field and hydroponic cultures,ZM-9131,CCRI-79,JM-958,and J-228 were identified as low-P-tolerant cotton cultivars,while JM-169,XM-33B,SCRC-28,and LNM-18 were identified as low P-sensitive cotton cultivars.The relationship between field and hydroponic screening results for low-P-tolerant cotton cultivars was strong,although field validation is still required.The low P tolerance of these cultivars was closely associ-ated with SDW and PUES. 展开更多
关键词 COTTON Hydroponic culture Field culture low phosphorus tolerance yield Fiber quality
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低产低效茶园综合改造研究进展
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作者 陈勋 胡晶晶 +9 位作者 张琳玲 安立进 陈超 黄丹娟 王红娟 焦龙 蒋白虎 黎珊财 冷杨 赵振军 《中国茶叶》 2026年第2期39-45,共7页
茶产业在我国农业经济中占据重要地位,但低产低效茶园的广泛存在,严重制约了其高效发展。文章阐述了我国低产低效茶园分布情况,低产低效茶园评估指标、主要类型、表现特征、形成原因及改造技术。同时,对改造后茶园经济效益、生态与景观... 茶产业在我国农业经济中占据重要地位,但低产低效茶园的广泛存在,严重制约了其高效发展。文章阐述了我国低产低效茶园分布情况,低产低效茶园评估指标、主要类型、表现特征、形成原因及改造技术。同时,对改造后茶园经济效益、生态与景观效益的协同提升进行了分析,旨在为提升茶园管理的科学性与效率、为我国低产低效茶园转型升级及茶产业的高质量发展提供更具针对性的理论与实践支撑。 展开更多
关键词 低产低效茶园 茶园改造 类型 管理技术
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低屈服点钢沙漏形钢棒阻尼器力学性能研究
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作者 连鸣 周玉浩 +1 位作者 苏明周 李伟 《工程力学》 北大核心 2026年第3期180-195,共16页
由LYP225低屈服点钢材制成的沙漏型钢棒阻尼器(LYP225-HBD)可用作结构中的耗能元件,以有效增强结构的地震耗能能力,最大限度地减少主要结构构件的地震损伤。对两个LYP225-HBD试件进行了低周往复加载试验。LYP225-HBD表现出稳定、饱满的... 由LYP225低屈服点钢材制成的沙漏型钢棒阻尼器(LYP225-HBD)可用作结构中的耗能元件,以有效增强结构的地震耗能能力,最大限度地减少主要结构构件的地震损伤。对两个LYP225-HBD试件进行了低周往复加载试验。LYP225-HBD表现出稳定、饱满的滞回曲线和出色的耗能能力;在滞回和疲劳加载过程中,阻尼器的破坏主要表现为耗能段裂纹发展引起的断裂;经过11倍屈服位移循环加载30圈后,仍能正常工作;在疲劳加载过程中,各项疲劳性能指标均满足相关规范要求;建立的初始刚度及屈服承载力计算公式与试验结果吻合较好,为LYP225-HBD的初步设计和参数优化提供了支持。利用ABAQUS建立了有限元分析模型,并通过试验验证了模型的准确性,对15个LYP225-HBD模型进行了参数分析。结果表明:LYP225-HBD的形状显著影响其承载能力、耗能能力和失效模式;随着耗能段内外径之比的增加,耗能段塑性发展区域减小,耗能能力降低,超强系数增大,建议内外径之比取0.45~0.55;随着耗能段长径比的增加,LYP225-HBD的承载力、刚度退化系数和耗能能力逐渐降低,建议长径比不超过4.75。该文的研究结果可为LYP225-HBD在建筑结构中的实际应用提供了参考。 展开更多
关键词 低屈服点钢 沙漏型钢棒阻尼器 滞回性能 疲劳性能 数值分析
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冷昼日数对东北三省水稻气象产量的影响
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作者 曲辉辉 朱海霞 +6 位作者 李秀芬 巩敬锦 王冬冬 孙丽莉 纪仰慧 王秋京 姜丽霞 《中国农业气象》 2026年第3期418-430,共13页
以东北水稻为研究对象,分析1980-2021年东北三省冷昼日数对水稻产量的影响,以期为极端低温事件对水稻产量影响评估提供参考。结果表明:1980-2021年东北三省水稻移栽-返青、返青-孕穗、孕穗-乳熟和乳熟-成熟4个生育阶段冷昼日数均呈减少... 以东北水稻为研究对象,分析1980-2021年东北三省冷昼日数对水稻产量的影响,以期为极端低温事件对水稻产量影响评估提供参考。结果表明:1980-2021年东北三省水稻移栽-返青、返青-孕穗、孕穗-乳熟和乳熟-成熟4个生育阶段冷昼日数均呈减少趋势,2009年为冷昼日数突变年,从2016年开始减少趋势达显著水平。水稻田间生长季冷昼日数对水稻相对气象产量呈极显著负效应,仅移栽-返青期为正效应。水稻孕穗-乳熟阶段冷昼日数对相对气象产量影响贡献率最大,达43%,即孕穗-乳熟阶段冷昼日数对东北三省水稻产量影响最大。辽宁省冷昼日数对相对气象产量影响的贡献率为东北三省最大,达到55%。水稻不同生育阶段冷昼日数对水稻相对气象产量存在一定交互影响,且交互影响可能放大移栽-返青阶段冷昼日数的正效应。未来东北三省水稻生产管理中,需重点关注孕穗-乳熟阶段冷昼的发生,并及时采取相应措施降低冷昼影响,保证水稻高产稳产。 展开更多
关键词 东北三省 极端低温事件 水稻 气象产量 贡献率
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加快老龄低产橡胶园更新的难点与举措
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作者 刘锐金 何长辉 +4 位作者 安锋 张晓飞 仇键 肖苏伟 李积华 《中国热带农业》 2026年第1期80-88,共9页
从维持生产潜力、优化树龄结构、加快新技术应用角度,系统阐释了推动老龄低产胶园更新的重要性和必要性,分析认为导致老龄低产胶园更新缓慢的关键原因是要素相对价格变化诱致产业比较效益明显减弱,而相应生产技术体系未能有效地对此作... 从维持生产潜力、优化树龄结构、加快新技术应用角度,系统阐释了推动老龄低产胶园更新的重要性和必要性,分析认为导致老龄低产胶园更新缓慢的关键原因是要素相对价格变化诱致产业比较效益明显减弱,而相应生产技术体系未能有效地对此作出调整和适应。建议下一步要摸清“家底”,科学制定未来10年的更新方案;锚定目标,强化土地、资金等要素保障;超前布局,加快新品种、新技术、新装备应用,谋划农机农艺融合发展;多措并举,增强支持政策预期,提高胶园单位土地面积产出率。同时,要加强天然橡胶生产保护区土地用途管制,增强地方政府激励,做好政策宣传。 展开更多
关键词 天然橡胶 老龄胶园 残次胶园、低产胶园 更新定植 科技支撑 生产能力
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中低产土壤接种根际促生细菌对玉米叶片生理特性的影响
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作者 刘桂民 宿磊 +5 位作者 郑晓宁 陈迪 刘丙花 孙铭婕 刘幸红 徐英梅 《中国农学通报》 2026年第3期119-124,共6页
针对中低产土壤养分亏缺制约玉米生长的问题,为明确根际促生细菌(PGPR)的缓解效应及机制,以玉米品种‘郑单958’为试材,设置对照、接种培养基、接种灭活菌剂、接种菌剂等4个处理,通过盆栽试验,试剂盒法测定叶片抗氧化酶活性、非酶抗氧... 针对中低产土壤养分亏缺制约玉米生长的问题,为明确根际促生细菌(PGPR)的缓解效应及机制,以玉米品种‘郑单958’为试材,设置对照、接种培养基、接种灭活菌剂、接种菌剂等4个处理,通过盆栽试验,试剂盒法测定叶片抗氧化酶活性、非酶抗氧化物质、渗透调节物质及内源激素含量等指标,分析PGPR对玉米生理特性的影响。结果表明,与对照相比,接种菌剂处理能显著提高玉米叶片的过氧化物酶(POD)、谷胱甘肽还原酶(GR)活性和非酶抗氧化物质、促进类激素含量,以及IAA/ABA、GA/ABA、ZT/ABA、(IAA+GA+ZT)/ABA比值,显著降低叶片可溶性糖、脯氨酸和脱落酸(ABA)含量,其中POD和GR活性分别较对照显著高出59.46%和56.91%,可溶性糖和ABA含量分别较对照显著降低40.32%和23.87%。此外,与接种菌剂处理相比,接种培养基和灭活菌剂处理对玉米叶片生理特性影响较小。综合分析可知,在玉米根部接种PGPR菌剂,能够通过调节玉米叶片抗氧化系统、渗透调节物质和内源激素含量以及内源激素平衡,进而增强玉米植株在中低产土壤中的适应能力。未来可明确PGPR接种浓度优化方案,开展多点田间试验,结合产量与品质指标,为中低产田玉米提质增效提供更全面的技术支撑。 展开更多
关键词 中低产土壤 根际促生细菌 玉米 抗氧化系统 内源激素平衡 渗透调节物质 抗逆性
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马铃薯耐低氮种质资源筛选与氮效率分析
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作者 许国春 许泳清 +5 位作者 李华伟 纪荣昌 罗文彬 林赵淼 邱思鑫 汤浩 《园艺学报》 北大核心 2026年第3期775-790,共16页
筛选耐低氮和氮高效种质对培育马铃薯绿色高效新品种具有重要意义。采用盆栽营养液控制试验方法,对180份马铃薯种质资源在低氮(0.1 mmol·L^(-1)NH_(4)NO_(3))和正常氮(10 mmol·L^(-1)NH_(4)NO_(3))处理下的叶片气体交换参数... 筛选耐低氮和氮高效种质对培育马铃薯绿色高效新品种具有重要意义。采用盆栽营养液控制试验方法,对180份马铃薯种质资源在低氮(0.1 mmol·L^(-1)NH_(4)NO_(3))和正常氮(10 mmol·L^(-1)NH_(4)NO_(3))处理下的叶片气体交换参数、相对叶绿素含量、地上部干物质积累和产量相关性状进行测定,分析各性状变异、相关性和低氮敏感性,筛选耐低氮和氮高效种质,并进行生理机制探讨和田间验证。结果表明,180份马铃薯种质资源的光合与产量相关性状变异显著,在正常氮和低氮处理下,9个性状的变异系数分别介于11.76%~73.04%和13.48%~112.13%之间;而且低氮处理下各性状的变异高于正常氮处理。测定性状两两之间多数具有较明显的相关关系,且在一定程度上受氮处理影响。低氮显著影响马铃薯叶片光合和产量性状,其中单株产量受低氮抑制最明显,其变异也最大,单株产量的耐低氮指数变异系数为57.53%。通过对单株产量耐低氮指数进行聚类,筛选获得10份耐低氮种质,其中7份属于双高效基因型(CIP8、CIP52、E33、CIP10、CIP16、T1和CIP66);在田间低氮条件下,耐低氮且氮高效种质同样具有较高的产量水平。分析发现,耐低氮种质比敏感种质具有更高的净光合速率、叶绿素含量、地上部干物质量和单株结薯数。本研究结果可为进一步挖掘优异基因资源和选育高产氮高效品种提供材料基础。 展开更多
关键词 马铃薯 种质资源 耐低氮种质 氮效率 产量 盆栽试验
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低氮和干旱对持绿型籼稻产量及生理指标的影响
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作者 王帮孝 付晓全 +4 位作者 钟蕾 傅军如 周大虎 贺浩华 陈小荣 《核农学报》 北大核心 2026年第1期171-182,共12页
生育后期功能叶持绿性能对籼型水稻抗逆防早衰、增强植株抗倒伏能力及高产稳产均具有重要意义。为探究籼稻持绿性与后期逆境适应性能间关系与作用机制,本试验选取两个自育籼型持绿自交系GKR1、GKR2,以常规籼稻品种黄华占(HHZ)为对照,于... 生育后期功能叶持绿性能对籼型水稻抗逆防早衰、增强植株抗倒伏能力及高产稳产均具有重要意义。为探究籼稻持绿性与后期逆境适应性能间关系与作用机制,本试验选取两个自育籼型持绿自交系GKR1、GKR2,以常规籼稻品种黄华占(HHZ)为对照,于穗期进行氮素亏缺和灌浆期干旱处理,考查叶绿素动态、产量形成及有关生理生化指标。结果表明,籽粒灌浆开始至成熟期,GKR1、GKR2叶片叶绿素含量高出黄华占20%~80%,差异整体达显著水平,且随熟期推进,其叶绿素含量下降始期更晚、降幅更低、降速更慢。与对照相比,两胁迫处理下GKR1、GKR2的产量下降幅度明显低于黄华占,主要体现在两持绿品系结实率和千粒重波动更小。正常或胁迫条件下,两持绿水稻羧化酶(Rubisco)活性和脱落酸(ABA)含量整体显著高于黄华占,而其丙二醛(MDA)、过氧化氢(H_(2)O_(2))含量均较低,可溶性糖含量较高;硝酸还原酶(NR)、谷氨酸合成酶(GOGAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性也较高。相关性分析显示,抽穗0 d的叶绿素a和叶绿素b含量与灌浆0 d的ABA含量和羧化酶活性及灌浆15 d时的GOGAT和NR活性均呈极显著正相关,使得两持绿籼稻在后期干旱与氮素亏缺条件下维持良好的生理机能,保证了逆境下的产量稳定性。综上,两持绿籼稻具有较为优良的抗逆稳产性能,该结果为其育种应用及相关基础研究奠定了良好基础。 展开更多
关键词 持绿籼稻 干旱胁迫 氮素亏缺 籽粒产量 作物生理
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土壤改良措施对玉米-大豆间作体系土壤结构、养分及作物产量的影响
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作者 李贺男 李锦朝 +7 位作者 付浩川 张浩磊 温家宣 庞津雯 方妍欣 董勤各 梁福琴 冯浩 《干旱地区农业研究》 北大核心 2026年第1期232-239,共8页
为解决黄土高原中低产田土壤结构差、肥力弱、作物产能低等问题,于2023年开展土壤改良田间试验,设传统施肥(CK)、γ-聚谷氨酸保水剂(P)、松土剂(S)、30%有机肥替代化肥(F)、30%有机肥替代化肥+γ-聚谷氨酸保水剂(FP)和30%有机肥替代化肥... 为解决黄土高原中低产田土壤结构差、肥力弱、作物产能低等问题,于2023年开展土壤改良田间试验,设传统施肥(CK)、γ-聚谷氨酸保水剂(P)、松土剂(S)、30%有机肥替代化肥(F)、30%有机肥替代化肥+γ-聚谷氨酸保水剂(FP)和30%有机肥替代化肥+松土剂(FS)共6个处理,研究不同改良措施对土壤结构、养分含量及玉米-大豆间作系统产量的影响。结果表明,与CK相比,各改良措施下土壤紧实度显著降低,降幅为15.90%~28.19%,玉米产量显著提高12.07%~30.73%。与CK相比,FS处理土壤容重显著降低7.01%,土壤团聚体平均重量直径(MWD)与几何平均直径(GMD)分别提高18.26%、21.96%,土壤有机质、全氮、有效磷含量分别显著增加44.70%、74.22%、100.95%,玉米的穗粒数、百粒重、产量分别提升16.11%、10.58%、30.73%。各改良措施对大豆产量和百粒重提升效果不显著。综上,30%有机肥替代+松土剂改良措施(FS)在改善土壤结构、土壤肥力和增加作物产量方面效果显著,推荐采用该方式来改善黄土高原区域旱地农业中低产田土壤质量,进而提高作物产量。 展开更多
关键词 土壤改良 土壤结构 土壤养分 玉米-大豆间作 产量 中低产田
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