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Pedosphere 2010年第5期20卷 674-680页

作者： AmANULLAH m.W.KHAN Department of agronomy Faculty of Crop Production SciencesKPK Agricultural University

Potassium(K) and phosphorus(P) applications improve growth,increase yield and yield components of sunflower(Helianthus annuus L.) on K and P deficient soils in Northwest Pakistan.A field experiment was conducted using sunflower ***-33 at the New Developmental Research Farm of KPK Agricultural University,Peshawar,Pakistan,during summer *** experimental design was a randomized complete block in split plot arrangements,with six levels of K(0,25,50,75,100,and 125 kg K ha-1) as main plots and four levels of P(0,45,90,and 135 kg P ha-1) as sub-plots with three *** yield and yield components responded positively to K and P fertilization but the magnitude of response varied with the levels of K and *** to flowering and maturity,grains per head,1000-grain weight,shelling percentage,and grain yield increased tremendously in the K and P-fertilized plots as compared to the control with no K and P *** combined application of 100 kg K and 45 kg P ha-1 significantly increased yield components,grain yield,harvest index,and shelling percentage of sunflower,suggesting that 100 kg K ha-1 in combination with 45 kg P ha-1 could maximize productivity of sunflower planted after wheat on the K and P deficient soils in the study area.

关键词： days to flowering days to maturity harvest index soil yield components

Rising from the dead: the power of genome editing

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science China(Life sciences) 2023年第12期66卷 2949-2951页

作者： Hongyuan Zheng Junyao Zhao Daowen Wang Zheng Qing Fu State Key Laboratory of Wheat and maize Crop science College of Agronomyand Center for Crop Genome EngineeringHenan Agricultural UniversityZhengzhou 450002China Department of Biological sciences University of South CarolinaColumbia SC 29208USA

To protect themselves against diverse pathogens, plants have developed sophisticated defense mechanisms. Hypersensitive response or the rapid localized death of plant cells is a major defense strategy deployed by plan... 详细信息

关键词： dead genome

Brain metastases Treated with Radio surgery Alone:An Alternative to Whole Brain Radiotherapy?

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癌症 2003年第7期22卷 784-784页

作者： Toshinori Hasegawa Douglas Kondziolka John C.Flickinger Anand Germanwala L.Dade Lunsford m.D. M.D.M.Sc.F.R.C.S.(C)M.D.M.D.M.D.

OBJECTIVE:Whole brain radiotherapy(WBRT)provides benefit for patients with b rain metastases but may result in neurological toxicity for patien ts with extended survival *** reotactic radiosurgery in combination with WBRT has become an important approach,but the value of WBRT has been *** an alternative to WBRT,we managed patients with stereotactic radiosurgery alone,evaluated pati ents’outcomes,and assessed prognostic factors for survival and tumor c ***:One hundred seventy-two patients with b rain metastases were managed with ra diosurgery *** hundred twent y-one patients were evaluable with follow-up imaging after *** median patien t age was 60.5years(age range,16-86yr).The mean marginal tumor dose and volume were 18.5Gy (range,11-22Gy )and 4.4ml (range,0.1-24.9ml ).Eighty percent of patients had soli tary ***:The overall median survival time *** median survival time in patients with no evidence of primary tumor disease or stable disease was 13and *** local tumor contr ol rate was 87%.At 2years,the rate of local control,remote brain control,and total intr acranial control were 75%,41%,and 27%,*** multivariate a nalysis,advanced primary tumor status(P=0.0003),older age(P=0.008),lower Karnofsky Performance scale score(P=0.01),and malignant melanoma (P=0.005)were significant for poorer surviva *** median survival time was 28mon ths for patients younger than 60years of age,with Karnofsky Performance scale score o f at least 90,and whose primary tumor status showed either no evidence of disease or stable *** volume (P=0.02)alone was significant for local tumo r control,whereas no factor affecte d remote or intracranial tumor contr *** patients developed complica tions,six of which were ***(16.5%)of 116patients in whom the cause of death was obtained died as a result of cause s related to brain ***:Brain metastases were controlled

关键词：脑转移瘤局部放射外科治疗全脑放射疗法比较

PHYSICAL mODEL FOR THE ENGINEERING ANALYSISOF THE THERmOELASTICLTY OF SOLID BODIES

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Chinese Journal of mechanical Engineering 2000年第3期13卷 165-170,177页

作者： Lucia Umberto I.N.F.m.-Istituto Nazionale per la Fisica della materia Nucl 意大利 Rivalta Sc I-15047

The thermal behaviour of the solids under elastic deformations is analysed in order to obtain a model which combines the molecular dynamics results with the global thermal behaviour of the solids under elastic transformations. The result obtained consists of the introduction of the thermal behaviour in the Parrinello-Rahman model, obtaining the thermal molecular dynamic model useful in the analysis of the thermoelastic behaviour of solids.

关键词： PHYSICAL mODEL FOR THE ENGINEERING ANALYSISOF THE THERmOELASTICLTY OF SOLID BODIES

Genotypic differences in callus induction and plant regeneration from mature embryos of barley(Hordeum vulgare L.)

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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2011年第5期12卷 399-407页

作者： Yong HAN Xiao-li JIN Fei-bo WU Guo-ping ZHANG Department of agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China

An efficient induction system and regeneration protocol based on mature barley embryos were *** isolated from mature seeds,dehusked by hand and inoculated with longitudinally bisected sections,showed low contamination and high primary callus-forming *** influences of nine culture media on primary callus induction and germination from the mature embryos of barley cultivars Golden Promise and Zaoshu 3 were *** results showed that the two cultivars had much higher values of primary callus induction in the B16m6D medium as compared to the other eight medium formulations,with a frequency of 74.3% and 78.4% for Golden Promise and Zaoshu 3,***,Zaoshu 3 demonstrated particularly high stability in callus induction over the different media,indicating its potential utilization in callus induction and regeneration for its good agronomic traits and wide *** were significant differences amongst 11 barley genotypes in terms of primary callus induction in the optimum medium,with percentages of callus induction and germination response ranging from 17.9% to 78.4% and 2.8% to 47.4%,*** plantlets of Dong 17,Golden Promise,and Zaoshu 3 were successfully de-veloped from primary calli through embryogenesis,with green plant differentiation frequencies ranging from 9.7% to 21.0% across genotypes.

关键词： Barley mature embryo Genotypic difference Primary callus Plant regeneration

migration and population genetics of the grain aphid macrosiphum m.sc.nti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural science:materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (College of agronomy and Biotechnology, China Agricultural University, Beijing 100094, China) College of agronomy and Biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid macrosiphum m.sc.nti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in China have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of m. m.sc.nti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： macrosiphum m.sc.nti microsatellite gene flow migration.

Increased plant density and reduced N rate lead to more grain yield and higher resource utilization in summer maize

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Journal of Integrative Agriculture 2016年第11期15卷 2515-2528页

作者： SHI De-yang LI Yan-hong ZHANG Ji-wang LIU Peng ZHAO Bin DONG Shu-ting agronomy College Shandong Agricultural University/State Key Laboratory of Crop Biology

Planting at an optimum density and supplying adequate nitrogen（N） to achieve higher yields is a common practice in crop production, especially for maize（Zea mays L.）; however, excessive N fertilizer supply in maize production results in reduced N use efficiency（NUE） and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index（LAI）, intercepted photosynthetically active radiation（IPAR）, and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958（ZD958） under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation（DmA）, grain yield, NUE, and radiation use efficiency（RUE）. However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DmA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK（320 kg ha^（–1）） was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^（–2）, compared to LD（5.25 plants m^（–2））, would lead to an optimal balance between yield and resource use efficiency.

关键词： summer maize increased plant density reduced N rate N use efficiency resource use efficiency

Soil Organic Carbon mineralization as Affected by Cyclical Temperature Fluctuations in a Karst Region of Southwestern China

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Pedosphere 2015年第4期25卷 512-523页

作者： CI En mahdi m.AL-KAISI WANG Liange DING Changhuan XIE Deti College of Resources and Environment Southwest University Department of agronomy Iowa State University

The diurnal fluctuation in soil temperature may influence soil organic carbon （SOC） mineralization, but there is no consensus on SOC mineralization response to the cyclical fluctuation in soil temperature. A 56-d incubation experiment was conducted to investigate the effects of constant and variable temperatures on SOC mineralization. Three soils were collected from the karst region in western Guizhou Province, southwestern China, including a limestone soil under forest, a limestone soil under crops and a yellow soil under crops. According to the World Reference Base （WRB） classification, the two limestone soils were classified as Haplic Luvisols and the yellow soil as a Dystric Luvisol. These soils were incubated at three constant temperatures （15, 20 and 25 ℃） and cyclically fluctuating temperatures （diurnal cycle between 15 and 25 ℃）. The results showed that the 56-d cumulative SOC mineralized （C56） at the fluctuating temperatures was between those at constant 15 and 25 ℃, suggesting that the cumulative SOC mineralization was restricted by temperature range. The SOC mineralization responses to the fluctuating temperatures were different among the three soils, especially in contrast to those at constant 20 ~C. Compared with constant 20 ℃, significant （P 〈 0.05） decreases and increases in C56 value were found in the limestone soil under forest and yellow soil under crops at the fluctuating temperatures, respectively. At the fluctuating temperatures, the forest soil with lower temperature coefficient Q10 （the relative change in SOC mineralization rate as a result of increasing the temperature by 10 ℃） had a significantly （P 〈 0.05） lower SOC mineralization intensity than the two cropland soils. These indicated that differences in temperature pattern （constant or fluctuating） could significantly influence SOC mineralization, and SOC mineralization responses to the fluctuating temperatures might be affected by soil characteristics. moreover, the warmer temperatures mi

关键词： labile C limestone soil recalcitrant C temperature coefficient (Q10) yellow soil

Relationship Between Grain Yield and Yield Components in Super Hybrid Rice

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Agricultural sciences in China 2011年第10期10卷 1537-1544页

作者： HUANG min ZOU Ying-bin JIANG Peng XIA Bing md Ibrahim AO He-jun College of agronomy Hunan Agricultural University Changsha 410128 P.R.China

Chinese super hybrid rice breeding project has developed many new varieties with great yield potential. It is controversial which yield component should be emphasized in super hybrid rice production. The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions, and evaluate relationships between grain yield and yield components of super hybrid rice in farmer’s paddy fields. Field experiments were done in Changsha, Guidong, and Nanxian, Hunan Province, China, from 2007 to 2009. Eight super hybrid varieties, one common hybrid variety, and one super inbred variety were grown in each location and year. Rice production investigation was undertaken in high-yielding （Guidong）, moderate-yielding （Nanxian）, and low-yielding （Ningxiang） regions of Hunan Province, China, in 2009. Grain yield and yield components were measured in both the field experiments and rice production investigation. Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years. Yield potential has been increased by 11.4% in super hybrid rice varieties compared with common and super inbred varieties. The higher yield of super hybrid varieties was attributed to improvement in panicle size. Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1, and was positively related to grain yield in farmer’s field at all of the high-, moderate-, and low-yielding regions. Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.

关键词： super hybrid rice yield panicle number panicle size