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Effects of Peat Extract on Crop Yields
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作者 LuoShengguo LiuShiyong 《Journal of Northeast Agricultural University(English Edition)》 CAS 1998年第2期104-110,共7页
This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports th... This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports the effect of this product on plant growth vigors such as plant height, leaf width and diameter of plant stem. 展开更多
关键词 Shibide(SBD) peat extract crop yields
全文增补中
Yields,growth and water use under chemical topping in relations to row configuration and plant density in drip-irrigated cotton 被引量:1
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作者 Wang Xuejiao Hu Yanping +10 位作者 Ji Chunrong Chen Yongfan Sun Shuai Zhang Zeshan Zhang Yutong Wang Sen Yang Mingfeng Ji Fen Guo Yanyun Li Jie Zhang Lizhen 《Journal of Cotton Research》 CAS 2024年第2期123-136,共14页
Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting m... Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting mode could achieve high yield,fiber quality and water use efficiency(WUE).This study aimed to explore if chemical topping affected cotton yield,quality and water use in relation to row configuration and plant densities.Results Experiments were carried out in Xinjiang China,in 2020 and 2021 with two topping method,manual topping and chemical topping,two plant densities,low and high,and two row configurations,i.e.,76 cm equal rows and 10+66 cm narrow-wide rows,which were commonly applied in matching harvest machine.Chemical topping increased seed cotton yield,but did not affect cotton fiber quality comparing to traditional manual topping.Under equal row spacing,the WUE in higher density was 62.4%higher than in the lower one.However,under narrow-wide row spacing,the WUE in lower density was 53.3%higher than in higher one(farmers’practice).For machine-harvest cotton in Xinjiang,the optimal row configuration and plant density for chemical topping was narrow-wide rows with 15 plants m-2 or equal rows with 18 plants m-2.Conclusion The plant density recommended in narrow-wide rows was less than farmers’practice and the density in equal rows was moderate with local practice.Our results provide new knowledge on optimizing agronomic managements of machine-harvested cotton for both high yield and water efficient. 展开更多
关键词 Yield components Fiber quality TRANSPIRATION Water use efficiency Heat ratio method(HRM)
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Managing cotton canopy architecture for machine picking cotton via high plant density and plant growth retardants 被引量:1
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作者 LAKSHMANAN Sankar SOMASUNDARAM Selvaraj +4 位作者 SHRI RANGASAMI Silambiah ANANTHARAJU Pokkharu VIJAYALAKSHMI Dhashnamurthi RAGAVAN Thiruvengadam DHAMODHARAN Paramasivam 《Journal of Cotton Research》 2025年第1期102-114,共13页
Machine picking in cotton is an emerging practice in India,to solve the problems of labour shortages and production costs increasing.Cotton production has been declining in recent years;however,the high density planti... Machine picking in cotton is an emerging practice in India,to solve the problems of labour shortages and production costs increasing.Cotton production has been declining in recent years;however,the high density planting system(HDPS)offers a viable method to enhance productivity by increasing plant populations per unit area,optimizing resource utilization,and facilitating machine picking.Cotton is an indeterminate plant that produce excessive vegeta-tive growth in favorable soil fertility and moisture conditions,which posing challenges for efficient machine picking.To address this issue,the application of plant growth retardants(PGRs)is essential for controlling canopy architecture.PGRs reduce internode elongation,promote regulated branching,and increase plant compactness,making cotton plants better suited for machine picking.PGRs application also optimizes photosynthates distribution between veg-etative and reproductive growth,resulting in higher yields and improved fibre quality.The integration of HDPS and PGRs applications results in an optimal plant architecture for improving machine picking efficiency.However,the success of this integration is determined by some factors,including cotton variety,environmental conditions,and geographical variations.These approaches not only address yield stagnation and labour shortages but also help to establish more effective and sustainable cotton farming practices,resulting in higher cotton productivity. 展开更多
关键词 COTTON High density planting system Plant growth retardant Canopy management Defoliators Machine picking Yield improvement
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Effects of Ultrasound-Assisted Alkaline Extraction on the Structural and Emulsifying Properties of Chickpea Protein Isolate
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作者 ZHANG Yixue YANG Qing +4 位作者 CHENG Teng ZHENG Ruihan MA Wuchao HE Xiangli LI Ke 《食品科学》 北大核心 2025年第19期236-247,共12页
This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of ... This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of chickpea protein isolate(CPI).Compared with the non-ultrasound group,ultrasound treatment at 400 W resulted in the largest increase in CPI yield,and both the particle size and turbidity decreased with increasing ultrasound power from 0 to 400 W.The scanning electron microscope results showed a uniform structural distribution of CPI.Moreover,itsα-helix content increased,β-sheet content decreased,and total sulfhydryl group content and endogenous fluorescence intensity rose,illustrating that UAE changed the secondary and tertiary structure of CPI.At 400 W,the solubility of the emulsion increased to 63.18%,and the best emulsifying properties were obtained;the emulsifying activity index(EAI)and emulsifying stability index(ESI)increased by 85.42%and 46.78%,respectively.Furthermore,the emulsion droplets formed were smaller and more uniform.In conclusion,proper UAE power conditions increased the extraction yield and protein content of CPI,and effectively improved its structure and emulsifying characteristics. 展开更多
关键词 CHICKPEA ULTRASOUND extraction yield protein structure functional properties
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Diagnostic yield and safety of pancreatic cystic lesions:A comparison between EUS-FNA and EUS-FNB
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作者 YU Xiaoyu YE Mingmei +5 位作者 NI Yawen LIU Qianqi GONG Pan HUANG Yuanyuan WANG Xiaoyan TIAN Li 《中南大学学报(医学版)》 北大核心 2025年第2期227-236,共10页
Objective:In recent years,the incidence and detection rate of pancreatic cystic lesions(PCLs)have increased significantly.Endoscopic ultrasound(EUS)plays an indispensable role in the diagnosis and differential diagnos... Objective:In recent years,the incidence and detection rate of pancreatic cystic lesions(PCLs)have increased significantly.Endoscopic ultrasound(EUS)plays an indispensable role in the diagnosis and differential diagnosis of PCLs.However,evidence comparing the diagnostic performance of EUS-guided fine-needle aspiration(EUS-FNA)and fine-needle biopsy(FNB)remains limited.This study aims to compare the diagnostic yield,adequacy of tissue acquisition,and safety between EUS-FNA and EUS-FNB in evaluating PCLs to inform clinical practice.Methods:A retrospective review was conducted on patients with PCLs who underwent either EUS-FNA or EUS-FNB between January 2014 and August 2021.The diagnostic yield,tissue acquisition adequacy,and incidence of adverse events were compared between the 2 groups.Results:A total of 90 patients with PCLs were included(52 in the FNA group and 38 in the FNB group).The diagnostic yield was similar between the FNA and FNB groups(94.2%vs 94.7%,P>0.05).The adequacy of tissue acquisition was 71.2%in the FNA group and 81.6%in the FNB group(P>0.05).No statistically significant difference was observed in the incidence of adverse events between the 2 groups(P>0.05).Conclusion:Both EUS-FNA and EUS-FNB demonstrate equally high diagnostic yields and tissue adequacy in PCLs,with excellent safety profiles.Both methods are safe and effective diagnostic tools for evaluating PCLs. 展开更多
关键词 endoscopic ultrasound-guided fine-needle aspiration endoscopic ultrasound-guided fine-needle biopsy pancreatic cystic lesions diagnostic yield SAFETY
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Static recrystallization behavior of cold-rolled AZ31 Mg alloy with high density of shear bands and{101^(-)1}twins
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作者 CHENG Zong-yuan PENG Jin-hua +3 位作者 FANG Tao ZANG Qian-hao CHEN Liang-yu LU Sheng 《Journal of Central South University》 2025年第3期727-743,共17页
Cold-rolling was conducted on AZ31 magnesium alloy with fine and coarse grains to produce plates with high density of shear bands and{101^(-)1}twins,respectively.Then,these two kinds of plates are subjected to isother... Cold-rolling was conducted on AZ31 magnesium alloy with fine and coarse grains to produce plates with high density of shear bands and{101^(-)1}twins,respectively.Then,these two kinds of plates are subjected to isothermal annealing to reveal the effect of shear bands and{101^(-)1}twins on recrystallization behavior.During annealing,static recrystallization occurs firstly in shear band zones and{101^(-)1}twin zones,which has different effect on texture and mechanical properties.With the increase of annealing temperature,strong basal texture remains in annealed SG-17%while the basal texture is weakened gradually in annealed LG-15%.Recrystallized grains from twin zones have a random orientation which is responsible for the weakened basal texture in annealed LG-15%.In addition,microhardness decreases gradually with the prolonged annealing time due to static recrystallization.LG-15%has a lower recrystallization activation energy because{101^(-)1}twins are in favor of the nucleation and growth of recrystallized grains.After 500℃annealing,the yield strength decreases significantly with a significant improvement in failure strain.The annealed LG-15%has a much higher compressive strain than the annealed SG-17%due to texture weakening effect. 展开更多
关键词 COLD-ROLLING isothermal annealing TWINNING TEXTURE yield strength
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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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What kind of cotton ideotype is adapted to agroecological cropping systems and climate change in Benin?
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作者 ABOUA Dègbédji Charlemagne GÉRARDEAUX Edward +2 位作者 DEBAEKE Philippe BOULAKIA Stéphane SEKLOKA Emmanuel 《Journal of Cotton Research》 2025年第3期319-332,共14页
Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertili... Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertility. A study was conducted in Benin from 2020 to 2023 to compare six different cotton cultivars in three agroecological cropping systems in two cotton-growing zones. Plough-based tillage plus incorporation of cover crop biomass(PTI), conservation agriculture with strip tillage(CA_ST), and conservation agriculture with no tillage(CA_NT) were compared with the reference plough-based tillage(PT). The objective was to identify morpho-physiological traits of cotton that increase yield in agroecological cropping systems. Our approach combined a field experiment and crop simulation model(CSM) of CROPGRO-Cotton to evaluate the effects of genotype(G) × environment(E) × management(M) interactions on seed cotton yield(SCY).Results Cultivars Tamcot_camde and Okp768 and simulated ideotypes performed best in CA systems. Increased seed mass, large and thick leaves, and later maturity were identified as beneficial for yield enhancement in CA systems. Cultivars and ideotypes that combine these traits also resulted in better nitrogen and water use efficiencies in CA systems. Under different climate scenarios up to 2050, ideotypes designed could increase SCY in Benin.Conclusion A set of morpho-physiological traits associated with vegetative vigour is required to ensure a good SCY in agroecological cropping systems. These results provide scientific evidence and useful knowledge for breeders and research programmes on cropping systems focused on the adaptation of cotton to climate change. 展开更多
关键词 TILLAGE Agroecological practices Water status Gossypium hirsutum IDEOTYPE Seed cotton yield Cover crop CSM-CROPGRO-Cotton
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Comparative analysis of machine learning and statistical models for cotton yield prediction in major growing districts of Karnataka,India
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作者 THIMMEGOWDA M.N. MANJUNATHA M.H. +4 位作者 LINGARAJ H. SOUMYA D.V. JAYARAMAIAH R. SATHISHA G.S. NAGESHA L. 《Journal of Cotton Research》 2025年第1期40-60,共21页
Background Cotton is one of the most important commercial crops after food crops,especially in countries like India,where it’s grown extensively under rainfed conditions.Because of its usage in multiple industries,su... Background Cotton is one of the most important commercial crops after food crops,especially in countries like India,where it’s grown extensively under rainfed conditions.Because of its usage in multiple industries,such as textile,medicine,and automobile industries,it has greater commercial importance.The crop’s performance is greatly influenced by prevailing weather dynamics.As climate changes,assessing how weather changes affect crop performance is essential.Among various techniques that are available,crop models are the most effective and widely used tools for predicting yields.Results This study compares statistical and machine learning models to assess their ability to predict cotton yield across major producing districts of Karnataka,India,utilizing a long-term dataset spanning from 1990 to 2023 that includes yield and weather factors.The artificial neural networks(ANNs)performed superiorly with acceptable yield deviations ranging within±10%during both vegetative stage(F1)and mid stage(F2)for cotton.The model evaluation metrics such as root mean square error(RMSE),normalized root mean square error(nRMSE),and modelling efficiency(EF)were also within the acceptance limits in most districts.Furthermore,the tested ANN model was used to assess the importance of the dominant weather factors influencing crop yield in each district.Specifically,the use of morning relative humidity as an individual parameter and its interaction with maximum and minimum tempera-ture had a major influence on cotton yield in most of the yield predicted districts.These differences highlighted the differential interactions of weather factors in each district for cotton yield formation,highlighting individual response of each weather factor under different soils and management conditions over the major cotton growing districts of Karnataka.Conclusions Compared with statistical models,machine learning models such as ANNs proved higher efficiency in forecasting the cotton yield due to their ability to consider the interactive effects of weather factors on yield forma-tion at different growth stages.This highlights the best suitability of ANNs for yield forecasting in rainfed conditions and for the study on relative impacts of weather factors on yield.Thus,the study aims to provide valuable insights to support stakeholders in planning effective crop management strategies and formulating relevant policies. 展开更多
关键词 COTTON Machine learning models Statistical models Yield forecast Artificial neural network Weather variables
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Zinc nutrition optimization for better cotton productivity on alkaline calcareous soil
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作者 ASHRAF M. QAMAR F. +4 位作者 MEHRAN M. MASOOD S. SHAHZAD S.M. JAVED M.S. AZHAR M.T. 《Journal of Cotton Research》 2025年第2期193-204,共12页
Background Zinc(Zn),being the most deficient micronutrient,can largely limit plant growth and development on alkaline calcareous soil.Crop species and varieties within species differently require Zn for optimum produc... Background Zinc(Zn),being the most deficient micronutrient,can largely limit plant growth and development on alkaline calcareous soil.Crop species and varieties within species differently require Zn for optimum productivity.The current study aimed to optimize Zn level and mode of application for better growth,yield,and fiber quality of cotton(Gossypium hirsutum L.).The experimental plan comprised a control group with no Zn application,three Zn levels through soil application,i.e.5 mg·kg^(-1)(SZn5),10 mg·kg^(-1)(SZn10),and 15 mg·kg^(-1)(SZn15),two levels of foliar application including 0.5%(FZn0.5)and 1%(FZn1)Zn solution,and various combinations of soil plus foliar application.Two cotton cultivars,CIM-663(Bt)and Cyto-124(non-Bt)were used,and each treatment was replicated thrice.Results Zinc nutrition caused a significant(P≤0.05)improvement in growth,yield,physiological,and fiber quality characteristics of both cotton cultivars.All levels and modes of Zn application were found effective in improving cotton productivity on alkaline calcareous soil.However,integrated soil application and foliar spray showed superiority over sole soil or foliar application.Among different treatments,SZn15+FZn1 caused the highest improvement in most of the observed growth and yield traits.The said treatment maximally increased the leaf Zn concentration by 270.5%and 218.4%with a subsequent increase in plant height 23.2%and 28.0%,monopodial branches 40.7%and 42.1%,sympodial branches 37.2%and 35.2%,seed cotton yield 32.5%and 36.6%,and lint yield 30.0%and 34.6%in CIM-663 and Cyto-124,respectively,compared with the control.SZn15+FZn1 also caused the highest increase in relative water contents 32.6%and 22.4%,chlorophyll contents 92.0%and 67.1%,and stomatal conductance 112.8%and 100.8%in CIM-663 and Cyto-124,respectively,compared with the control.Among the fiber quality characteristics,fiber fineness was maximally improved by 19.7%and 15.9%in CIM-663 and Cyto-124,respectively,with SZn15+FZn1 compared with the control.Leaf Zn concentration was positively correlated with fiber length(R2=0.7173),fiber strength(R2=0.5483),and fiber fineness(R2=0.6379)of both cotton cultivars grown with different levels and application modes of Zn.The benefit-cost ratio was remarkably improved with Zn nutrition,and the highest value of 1.64 was found in CIM-663 at SZn10+FZn1 and SZn15+FZn1.Conclusion The plant growth,physiological,yield,and fiber quality characteristics of cotton cultivars were significantly improved with Zn supply at different levels and modes of application.SZn15+FZN1 could be recommended to get optimum seed cotton yield and fiber quality of cotton on alkaline calcareous soil. 展开更多
关键词 Boll weight CHLOROPHYLL Fiber quality Foliar spray Monopodial branches PHOTOSYNTHESIS Seed cotton yield Sympodial branches
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Determination of support mechanical mechanism of pre-stressed expandable props to stope roof in room-and-pillar mining
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作者 LI Kun-meng WANG Yong-jiang +3 位作者 LIU Kai LI Yuan-hui FU Zheng-chun PANG Bo-xue 《Journal of Central South University》 2025年第9期3539-3556,共18页
This study is to determine the support mechanism of pre-stressed expandable props for the stope roof in room- and-pillar mining, which is crucial for maintaining stability and preventing roof collapse in mines. Utiliz... This study is to determine the support mechanism of pre-stressed expandable props for the stope roof in room- and-pillar mining, which is crucial for maintaining stability and preventing roof collapse in mines. Utilizing an engineering case from a gold mine in Dandong, China, a laboratory-based similar test is conducted to extract the actual roof characteristic curve. This test continues until the mining stope collapses due to a U-shaped failure. Concurrently, a semi-theoretical method for obtaining the roof characteristic curve is proposed and verified against the actual curve. The semi-theoretical method calculated that the support force and vertical displacement at the demarcation point between the elastic and plastic zones of the roof characteristic curve are 5.0 MPa and 8.20 mm, respectively, corroborating well with the laboratory-based similar test results of 0.22 MPa and 0.730 mm. The weakening factor for the plastic zone in the roof characteristic curve was semi-theoretically estimated to be 0.75. The intersection between the actual roof characteristic curve and the support characteristic curves of expandable props, natural pillars, and concrete props indicates that the expandable prop is the most effective “yielding support” for the stope roof in room-and-pillar mining. That is, the deformation and failure of the stope roof can be effectively controlled with proper release of roof stress. This study provides practical insights for optimizing support strategies in room-and-pillar mining, enhancing the safety and efficiency of mining operations. 展开更多
关键词 expandable prop room-and-pillar mining complex variable function roof characteristic curve support characteristic curve yielding support
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栽培密度和施肥量对甜玉米金玉甜1号农艺性状和产量的影响 被引量:17
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作者 潘彬荣 岳高红 +4 位作者 许立奎 楼珏 梅喜雪 周志辉 张宗宸 《江西农业学报》 CAS 2010年第8期9-11,15,共4页
研究了不同的栽培密度和施肥量对甜玉米金玉甜1号的农艺性状和产量的影响,结果表明:金玉甜1号的最适栽培密度为4.20万株/hm2,氮肥施用量为225 kg/hm2。
关键词 栽培密度 密度和施肥量 甜玉米 金玉 农艺性状 产量 Sweet Corn Yield AGRONOMIC Traits 氮肥施用量 结果
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施肥位置对木薯产量和生长的影响 被引量:10
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作者 黄洁 刘子凡 +2 位作者 许瑞丽 叶剑秋 李开绵 《江西农业学报》 CAS 2010年第10期15-16,26,共3页
进行了2个木薯品种、5个施肥位置的裂区试验,结果发现:在茎基部、茎基顶中间和茎侧中间施肥,木薯的鲜薯产量比茎侧施肥(CK)提高10.2%~17.3%,鲜薯淀粉产量比CK提高12.7%~19.0%。因此宜在种茎基部至茎基顶中间之间,即离茎基部15~30cm... 进行了2个木薯品种、5个施肥位置的裂区试验,结果发现:在茎基部、茎基顶中间和茎侧中间施肥,木薯的鲜薯产量比茎侧施肥(CK)提高10.2%~17.3%,鲜薯淀粉产量比CK提高12.7%~19.0%。因此宜在种茎基部至茎基顶中间之间,即离茎基部15~30cm处定点施肥;对木薯苗施肥时,可在茎基顶中间或茎侧中间施肥。 展开更多
关键词 施肥位置 木薯品种 鲜薯产量 生长 Yield 裂区试验 淀粉产量 结果 定点
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基于GIS的黄土丘陵沟壑区作物生产潜力模拟研究 被引量:12
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作者 李忠武 蔡强国 +2 位作者 Scott Mitchell 唐政洪 Ferko Csillag 《生态学报》 CAS CSCD 北大核心 2002年第3期311-317,共7页
从 YIELD模型的来源、输入文件及基本参数、模型中作物生产力计算各个子模型以及计算流程 4个方面作了简单的叙述 ,以黄土丘陵沟壑区典型小流域晋西狼窝沟为例 ,在地理信息系统 ( GIS)技术支持下 ,应用 YIELD模型对该流域的作物生产潜... 从 YIELD模型的来源、输入文件及基本参数、模型中作物生产力计算各个子模型以及计算流程 4个方面作了简单的叙述 ,以黄土丘陵沟壑区典型小流域晋西狼窝沟为例 ,在地理信息系统 ( GIS)技术支持下 ,应用 YIELD模型对该流域的作物生产潜力进行了模拟 ,并从作物类型、地类、耕作措施及气候条件 4个方面对影响该流域作物产量的因素进行分析。结果表明 ,该模型对不同作物的模拟产量在总体上与实测产量基本相符合 ,表明模型可以应用于黄土丘陵沟壑区的作物产量模拟之中 ;对于不同地类来说 ,坝地的土壤水分和肥力条件明显高于梯田和坡耕地 ,因而坝地的模拟产量也高于梯田和坡地 ,但三者之间的差距没有实测产量显著 ;耕作措施是提高作物生产力的有效途径 ,对地膜覆盖、梯田以及施肥等耕作措施的模拟产量表明 ,这 3种耕作措施均能有效的提高作物生产力 ,其产量提高率均平均在 85 %以上 ,其中以施肥对作物的增产作用最大 ,增产率高达 95 % ,这与实测产量资料基本一致 ;气候条件是影响作物生产的直接因素 ,模拟结果表明模型对降水量和温度等气候条件十分敏感 ,不同年份降水量和温度的差异将直接导致作物生产力的显著不同。对 YIELD模型的模拟结果分析表明 。 展开更多
关键词 GIS 地类 耕作措施 气候条件 YIELD模型 黄土丘陵沟壑区 作物生产力 模拟
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基于CAN总线的谷物产量快速计量系统研发(英文) 被引量:8
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作者 安晓飞 孟志军 +2 位作者 武广伟 李立伟 魏学礼 《农业工程学报》 EI CAS CSCD 北大核心 2015年第S2期262-266,共5页
It depended on the spatial and temporal variation of soil and grain yield to implement precision agriculture.Grain yield monitoring on combine harvester was a cornerstone of precision fertilization.The intelligent gra... It depended on the spatial and temporal variation of soil and grain yield to implement precision agriculture.Grain yield monitoring on combine harvester was a cornerstone of precision fertilization.The intelligent grain yield monitoring system with the sensors and DGPS(differential global positioning system),which was loaded on the combine harvester,could get the different blocks’yield and produce the yield map.In this study,a new grain yield monitoring system based on CAN bus technology was developed.The system consisted of sensor unit,data acquisition unit,GPS module and LCD(liquid crystal display)terminal.The grain yield data were collected by the grain flow sensor,and processed by the signal condition circuit.And then the grain yield data and GPS signal were transmitted to the control unit by CAN bus.With the algorithm of grain yield conversion,all the collected data including real-time grain yield,harvest area and average grain yield were displayed on the LCD terminal.Flow sensor unit included grain yield flow sensor,force impact plate and mounting bracket.The sensor frame was mounted at the top of clean grain elevator of combine harvester.When the elevator paddles rotated around the sprocket,grain was propelled towards a flat impact plate.As grain momentum was lost in the subsequent collision with the impact plate,an effective force was measured by the impact parallel-beam load cell.Along with the calibration relationship between measured force and mass flow rate,the output of the impact parallel-beam load cell could indicate the flow rate of grain yield.Data acquisition unit included power conversion circuit,sensor signal acquisition circuit,analog-to-digital conversion circuit and CAN communication circuit.It could fulfill data acquisition function,CAN communication function and interrupt handling function.LCD terminal had the function of sensor detection,the function of GPS information collection,parameter calibration,data display and storage.It could display the real-time grain yield,total yield,average yield and harvest area.In order to evaluate the grain yield monitoring system,3 experiments which included static performance experiment of grain yield flow sensor,platform test experiment of grain yield monitoring system and dynamic performance experiment on combine harvester were carried out.The result of platform test experiment showed that the system error between predicted yield and measured yield was less than 3%and the system could avoid the effect of vibration from the platform effectively.Field dynamic experiment showed that the system error was less than 5%.Both the experimental results indicated that the grain yield monitoring system could satisfy the need of practical production. 展开更多
关键词 AGRICULTURE CROPS YIELD YIELD flow sensor CAN BUS
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基于WIN-YIELD软件的黄土丘陵区作物产量地形分异模拟 被引量:11
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作者 徐勇 甘国辉 王志强 《农业工程学报》 EI CAS CSCD 北大核心 2005年第7期61-64,共4页
退耕还林是目前黄土丘陵区整治生态环境和控制水土流失的主体政策。为提高退耕政策贯彻落实的科学性,该文基于WIN-YIELD软件,利用2002年延安气象站的逐日气象数据和燕沟流域地貌、土壤及土地利用等资料,通过对玉米、马铃薯、高粱、大豆... 退耕还林是目前黄土丘陵区整治生态环境和控制水土流失的主体政策。为提高退耕政策贯彻落实的科学性,该文基于WIN-YIELD软件,利用2002年延安气象站的逐日气象数据和燕沟流域地貌、土壤及土地利用等资料,通过对玉米、马铃薯、高粱、大豆和豌豆等作物产量随地形高程、坡度和坡向变化的模拟,以揭示作物产量与地形条件的关系。研究发现:地形坡度对作物的产量有着重要影响,地形坡度越大,作物的产量越低;地形高程除对马铃薯有一定影响外,对其它作物产量的影响不大;地形坡向对不同作物产量的影响普遍较微弱。 展开更多
关键词 作物产量 地形分异 WIN—YIELD软件 黄土丘陵区
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不同密度与施肥水平对玛咖产量的影响 被引量:19
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作者 李国庆 郭承刚 +3 位作者 杨少华 薛润光 和寿星 赵菊 《江西农业学报》 CAS 2010年第9期84-86,共3页
在海拔2730 m的云南丽江金安乡进行种植密度、纯氮用量、纯磷用量和纯钾用量4个因素的正交试验,研究不同密度和施肥水平对玛咖产量的影响。结果表明,磷肥用量和种植密度对玛咖的产量有极显著影响,而氮肥用量和钾肥用量对玛咖的影响不明... 在海拔2730 m的云南丽江金安乡进行种植密度、纯氮用量、纯磷用量和纯钾用量4个因素的正交试验,研究不同密度和施肥水平对玛咖产量的影响。结果表明,磷肥用量和种植密度对玛咖的产量有极显著影响,而氮肥用量和钾肥用量对玛咖的影响不明显。玛咖产量较高的是第5组合和第7组合,两者差异不显著,两组合的共同点是施用的纯磷量均达600 kg/hm2。该研究结果可为玛咖的大田生产提供参考。 展开更多
关键词 不同密度 施肥水平 玛咖 产量 Yield Levels 种植密度 组合 正交试验 云南丽江 磷肥用量 两者差异 结果 钾肥用量 氮肥用量 磷用量 钾用量 共同点 氮用量 施用
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温、湿度对假眼小绿叶蝉种群数量及梢内着卵量的影响 被引量:13
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作者 李慧玲 林乃铨 《福建农业学报》 CAS 2012年第1期55-59,共5页
探讨茶园假眼小绿叶蝉的成虫、若虫及茶梢内着卵量的种群动态,以及温湿度对茶园中叶蝉种群数量的影响。结果表明,①成虫、若虫及梢内着卵量均有2个高峰期,分别出现在5月中旬至6月中旬和9月下旬至10月中旬,且成虫、若虫和卵三者都呈显著... 探讨茶园假眼小绿叶蝉的成虫、若虫及茶梢内着卵量的种群动态,以及温湿度对茶园中叶蝉种群数量的影响。结果表明,①成虫、若虫及梢内着卵量均有2个高峰期,分别出现在5月中旬至6月中旬和9月下旬至10月中旬,且成虫、若虫和卵三者都呈显著的正相关。②假眼小绿叶蝉的成虫、若虫虫口数量受田间气候条件影响较大,温度对假眼小绿叶蝉的影响最大,茶梢内假眼小绿叶蝉的着卵量与温度关系很密切,气温高于28℃或者低于20℃都不适宜小绿叶蝉产卵繁殖。③对温度和田间假眼小绿叶蝉成、若虫种群数量及梢内着卵量进行统计分析,结果表明,温度与假眼小绿叶蝉的成、若虫虫口数量、茶梢内着卵量呈现Yield Density模型变化规律。 展开更多
关键词 温度 相对湿度 假眼小绿叶蝉 种群动态 YIELD Density模型
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温度和盐度对短节硬毛藻(Chaetomorpha brachygona Harvey)生长发育的影响研究 被引量:3
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作者 丁兰平 李雯诗 +2 位作者 谭华强 颜泽伟 黄冰心 《海洋与湖沼》 CAS CSCD 北大核心 2015年第1期191-196,共6页
利用双因素实验和单藻培养等方法,对采自广东南澳岛的短节硬毛藻(Chaetomorpha brachygona Harvey)进行研究,在不同温度和盐度条件下,对该硬毛藻的生长、活力以及形态进行了观察与测定。结果表明,温度和盐度对短节硬毛藻的生长均有一定... 利用双因素实验和单藻培养等方法,对采自广东南澳岛的短节硬毛藻(Chaetomorpha brachygona Harvey)进行研究,在不同温度和盐度条件下,对该硬毛藻的生长、活力以及形态进行了观察与测定。结果表明,温度和盐度对短节硬毛藻的生长均有一定影响,当温度为20°C时,藻体培养第3、6和12天活力分别为0.70—0.75Y、0.60—0.70Y和0.55—0.65Y,培养12天时藻体有生殖细胞形成,此温度有利于藻体维持活力;温度为25—30°C时,培养第3天时会大量形成生殖细胞;在盐度10、20、40和50时,藻体的生长与温度相关,即30°C>25°C>20°C;在盐度20—30时,藻体长度最大达4.55 cm;在盐度10—30时,更有利于藻体生长,整体趋势为20>30>10>40>50。因此,实验条件下,温度25—30°C、盐度10—30更利于短节硬毛藻的生长和形成生殖细胞。本实验表明,短节硬毛藻为暖水、广盐性种,有可能在我国南方海区大量生长并扩散,具有引发绿潮的潜力。 展开更多
关键词 短节硬毛藻 环境因子 绿潮藻 量子产量Yield
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氮磷钾肥对紫云英产量、养分累积及种植后土壤养分的影响 被引量:8
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作者 李昱 何春梅 +5 位作者 杨仁仙 张辉 李清华 王飞 刘志华 林新坚 《江西农业学报》 CAS 2010年第11期112-114,共3页
通过田间试验,研究了不同配比的NPK肥对紫云英生长、产量、养分累积及土壤养分的影响。研究结果表明:种植紫云英后土壤速效钾、碱解氮、有机质、pH值提高,土壤有效磷下降。施用P2O5在54 kg/hm2内时,紫云英产量随着施磷的增加而增加,并... 通过田间试验,研究了不同配比的NPK肥对紫云英生长、产量、养分累积及土壤养分的影响。研究结果表明:种植紫云英后土壤速效钾、碱解氮、有机质、pH值提高,土壤有效磷下降。施用P2O5在54 kg/hm2内时,紫云英产量随着施磷的增加而增加,并且在早春适当施少量的氮肥(施尿素30 kg/hm2),可以提高紫云英产量。施钾对紫云英产量影响不大,原因有待于进一步研究。 展开更多
关键词 氮磷钾肥 紫云英生长 产量影响 养分累积 种植 土壤养分 Yield 土壤有效磷 土壤速效钾 田间试验 不同配比 有机质 碱解氮 NPK肥 早春 施用 尿素 结果 氮肥
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