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Journal of Animal Science and Biotechnology 2024年第4期15卷 1751-1760页

作者： Su A Lee Diego A.Rodriguez Chad B.Paulk Hans H.Stein Department of Animal Sciences University of IllinoisUrbanaIL 61801USA Department of Grain Sciences and Industry Kansas State UniversityManhattanKS 66506USA

Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable *** may also reduce particle size of grain,but it is not known if there are interactions between particle size reduction and *** objective of this experiment was to test the hypothesis that particle size reduction and pelleting,separately or in combination,increase N balance,apparent total tract digestibility(ATTD)of fiber and fat,and net energy(NE)in corn-soybean meal diets fed to group-housed *** Six corn-soybean meal-based diets were used in a 3×2 factorial design with 3 particle sizes of corn(i.e.,700,500,or 300μm)and 2 diet forms(i.e.,meal or pelleted).Pigs were allowed ad libitum access to feed and ***-four castrated male pigs(initial weight:29.52 kg;standard diviation:1.40)were allotted to the 6 diets using a 6×6 Latin square design with 6 calorimeter chambers(i.e.,4 pigs/chamber)and 6 *** consumption and CO_(2)and CH_(4)productions were measured during fed and fasting states and fecal and urine samples were *** Regardless of particle size of corn,the ATTD of gross energy(GE),N,and acid-hydrolyzed ether extract(AEE),and the concentration of NE were greater(Pcorn,but the increase was greater in meal diets than in pelleted diets(interaction;Pcorn particle size increased nutrient digestibility and NE,but increases were greater in meal diets than in pelleted diets.

关键词： corn Digestibility Feed technology Net energy Particle size Pelleting

Design and optimization of the seed conveying system for belt-type highspeed corn seed guiding device

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 123-131页

作者： Yifei Li Wenqi Zhou Chengcheng Ma Zhaohua Feng Jinwu Wang Shujuan Yi Song Wang College of Engineering Northeast Agricultural UniversityHarbin 150030China College of Engineering Heilongjiang Bayi Agricultural UniversityDaqing 163000HeilongjiangChina Agricultural Engineering Department Qitaihe Vocational Technician CollegeQitaihe 154600HeilongjiangChina

Seeding is an important part of improving corn ***,seed guide tubes are mostly used as transport *** the existing seed guide tubes cannot meet the requirements or achieve the goal of fixing the seed falling trajectory.A seed collision phenomenon occurs ***,in response to the problems that the seeds and seed guide tube collide or bounce under high speed operation,which results in a lower sowing qualification rate and poor spacing uniformity,a seed receiving and conveying system comprising a belt-type high-speed corn seed guiding device was designed and optimized,to meet the needs of high-speed precision sowing operations and improve the spacing *** factors affecting the seed conveying performance were obtained by analyzing the mechanical properties of the seeds at various movement *** factors were the number of seed cavities between adjacent seeds,the forward speed,the height from the ground,and the installation *** factor simulation experiments were conducted by selecting the paddle spacing as the test factor and using the pass rate,reseeding rate,omission rate and coefficient of variation as the evaluation indexes to investigate the influence of the paddle spacing on the seed guide performance of the device and further determine the structural parameters of the paddle *** rotation combination tests of three factors and five levels were also conducted through bench *** the test outcomes were *** results indicated that the best results were obtained when the number of seed cavity intervals between adjacent seeds was 5.16,the installation angle was 79.40°,and the height from the ground was 31.84 *** this time,the qualified rate was 98.49%,the repeated sowing rate was 0.48%,the missed sowing rate was 1.03%,and the coefficient of variation was 6.80%.Experiments were used to validate the optimization results,and all of the obtained index data satisfied the criteria for accurate

关键词： corn high-speed sowing belt-type seed guide device test

Humic Acid Effects on Reducing corn Leaf Burn Caused by Foliar Spray of Urea-Ammonium Nitrate at Different Humic Acid/Urea-Ammonium Nitrate Ratios

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Open Journal of Soil Science 2024年第3期14卷 180-189页

作者： Xinhua Yin Department of Plant Sciences The University of Tennessee Jackson USA

Technologies for reducing corn leaf burn caused by foliar spray of urea-ammonium nitrate (UAN) during the early growing season are limited. A field experiment was carried out to evaluate the effects of humic acid on corn leaf burn caused by foliar spray of undiluted UAN solution on corn canopy at Jackson, TN in 2018. Thirteen treatments of the mixtures of UAN and humic acid were evaluated at V6 of corn with different UAN application rates and different UAN/humic acid ratios. Leaf burn during 1 2, 3, 4, 5, 6, 7, and 14 days after UAN foliar spray significantly differed between with or without humic acid addition. The addition of humic acid to UAN significantly reduced leaf burn at each UAN application rate (15, 25, and 35 gal/acre). The reduction of leaf burn was enhanced as the humic acid/UAN ratio went up from 10% to 30%. Leaf burn due to foliar application of UAN became severer with higher UAN rates. The linear regression of leaf burn 14 days after application with humic acid/UAN ratio was highly significant and negative. However, the linear regression of leaf burn 14 days after application with the UAN application rate was highly significant and positive. In conclusion, adding humic acid to foliar-applied UAN is beneficial for reducing corn leaf burn during the early growing season.

关键词： Humic Acid Urea-Ammonium Nitrate corn Leaf Burn N rate Ratio

Evaluation of Ruminal Dry Matter Disappearance and pH of Dry corn, High-Moisture corn, and Rye under in Vitro Conditions

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Agricultural Sciences 2024年第3期15卷 327-332页

作者： Warren Carl Rusche Zachary Kidd Foster Smith South Dakota State University Brookings South Dakota USA

An in vitro experiment was conducted to evaluate the effects of grain type on in vitro dry matter disappearance (IVDMD) and pH using ruminal fluid and a buffer reagent. Five beef cows were used for ruminal fluid collection and ruminal fluid was pooled prior to use. The cows used for ruminal fluid collection were maintained on a forage-based diet (60:40 forage to concentrate) for 28 d prior to ruminal fluid collection. Three grain types were evaluated: 1) dry corn (89% dry matter;DRC), 2) high-moisture corn (72% dry matter;HMC) and 3) rye (89% dry matter;RYE). Data were analyzed as a completely randomized design. A total of twenty-one replications of each grain type were used for statistical analysis (n = 63 tubes total). IVDMD was greater (P ≤ 0.05) by 97.1% and 46.4% for RYE compared to DRC and HMC, respectively. Additionally, IVDMD was greater (P = 0.05) by 34.6% for HMC compared to DRC. Final pH was decreased (P ≤ 0.05) for RYE by 12.3% and 2.8% for RYE compared to DRC and HMC, respectively. Also, final pH was decreased (P = 0.05) by 9.8% for HMC compared to DRC. These data indicate that corn harvest method (dry vs. high-moisture) influences IVDMD and final pH and that rye has a greater disappearance of dry matter and lower final pH than corn under in vitro conditions.

关键词： corn Grain Processing Ruminal Fermentation Rye

Effect on anaerobic digestion performance of corn stover by freezing–thawing with ammonia pretreatment

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Chinese Journal of Chemical Engineering 2019年第1期27卷 200-207页

作者： Hairong Yuan Yanyan Lan Jialin Zhu Akiber Chufo Wachemo Xiujin Li Liang Yu Centre for Resource and Environmental Research Beijing University of Chemical Technology China National General Machinery Engineering Corporation Department of Water Supply and Environmental Engineering Arba Minch University Department of Biological Systems Engineering Washington State University

In order to enhance the biomethane production from corn stover, choosing effective pretreatment is one of the necessary steps before starting anaerobic digestion(AD).This study was aimed to analyze the effectiveness of freezing–thawing with ammonia pretreatment on substance degradation and AD performance of corn *** ammonia concentrations(2%, 4%, and 6%) with two different moisture contents(50% and 70%) were used to pretreat the corn stover at two temperatures(-20 ℃ and 20 ℃).The result showed that an optimum pretreatment condition for corn stover was at the temperature of -20 ℃, moisture content of 70% and ammonia concentration of 2%.Under the optimum pretreatment condition, the maximum biomethane yield reached 261 ml·(g VS)^(-1), which was 41.08% higher than that of the *** different pretreatment conditions,the highest loss of lignin at -20 ℃ with 2% ammonia concentration was 63.36% compared with the *** buffer capacity of AD system was also improved after the freezing–thawing with ammonia ***, the freezing–thawing with ammonia pretreatment can be used to improve AD performance for corn *** study provides further insight for exploring an efficient freezing–thawing with ammonia pretreatment strategy to enhance AD performance for the practical application.

关键词： Freezing–thawing Ammonia pretreatment Anaerobic digestion corn stover

corn Yield Forecasting in Northeast China Using Remotely Sensed Spectral Indices and Crop Phenology Metrics

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Journal of Integrative Agriculture 2014年第7期13卷 1538-1545页

作者： WANG Meng TAO Fu-lu SHI Wen-jiao Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Early crop yield forecasting is important for food safety as well as large-scale food related planning. The phenology-adjusted spectral indices derived from Moderate Resolution Imaging Spectroradiometer （MODIS） data were used to develop liner regression models with the county-level corn yield data in Northeast China. We also compared the different spectral indices in predicting yield. The results showed that, using Enhanced Vegetation Index （EVI）, Normalized Difference Water Index （NDWI） and Land Surface Water Index （LSWI）, the best time to predict corn yields was 55-60 days after green-up date. LSWI showed the strongest correlation （R2=0.568）, followed by EVI （R2=0.497） and NDWI （R2=0.495）. The peak correlation between Wide Dynamic Range Vegetation Index （WDRVI） and yield was detected 85 days after green-up date （RZ=0.506）. The correlation was generally low for Normalized Difference Vegetation Index （NDVI）（R2=0.385） and no obvious peak correlation existed for NDVI. The coefficients of determination of the different spectral indices varied from year to year, which were greater in 2001 and 2004 than in other years. Leave-one-year-out approach was used to test the performance of the model. Normalized root mean square error （NRMSE） ranged from 7.3 to 16.9% for different spectral indices. Overall, our results showed that crop phenology-tuned spectral indices were feasible and helpful for regional corn yield forecasting.

关键词： remote sensing yield corn MODIS phenology

Enrichment of thermophilic and mesophilic microbial consortia for efficient degradation of corn stalk

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Journal of Environmental Sciences 2019年第4期31卷 118-126页

作者： Jun Lu Zhiman Yang Wanying Xu Xiaoshuang Shi Rongbo Guo Shandong Industrial Engineering Laboratory of Biogas Production & Utilization Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences

Six different environmental samples were applied to enrich microbial consortia for efficient degradation of corn stalk,under the thermophilic and mesophilic *** consortium obtained from anaerobic digested sludge under thermophilic condition(TC-Y)had the highest lignocellulose-degrading *** CO_2yield was 246.73 m L/g VS in23 days,meanwhile,the maximum CO_2production rate was 15.48 mL/(CO_2·d),which was28.75%and 52.27%higher than that under mesophilic condition,*** peak value of cellulase activity reached 0.105 U/mL,which was at least 34.61%higher than the other *** addition,49.5%of corn stalk was degraded in 20 days,moreover,the degradation ratio of cellulose,hemicellulose and lignin can reach 52.76%,62.45%and42.23%,*** consortium structure analysis indicated that the TC-Y contained the phylum of Gemmatimonadetes,Acidobacteria,Chloroflexi,Planctomycetes,Firmicutes,and ***,the Pseudoxanthomonas belonging to GammaProteobacteria might be the key bacterial group for the lignocellulose *** results indicated the capability of degrading un-pretreated corn stalk and the potential for further investigation and application of TC-Y.

关键词： corn stalk Lignocellulose degradation Microbial consortium Bacterial community structure

Fertilizer-Induced Advances in corn Growth Stage and Quantitative Definitions of Nitrogen Deficiencies

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Pedosphere 2008年第1期18卷 60-68页

作者： J. ZHANG A. M. BLACKMER P. M. KYVERYGA B. W. VAN DE WOESTYNE T. M. BLACKMER Department of Agronomy Iowa State University Ames IA 50011 (USA) Iowa Soybean Association 4554 114th Street Urbandale IA 50322 (USA) John Deere Ag Management Solutions 140 114th Street Urbandale IA 50322 (USA) Statistieal Consulting Center 130 MM Wright State University Dayton OH 45435 (USA)

Evidence that nitrogen (N) fertilization tends to accelerate maturation as well as increase rates of growth has received little attention when diagnosing N deficiencies in corn (Zea mays L.).Such a tendency could be a potential source of errors when the diagnosis is solely based on comparing plants with different rates of *** N fertilization could accelerate rates of growth and maturation was tested in a field study with 12 paired plots representing relatively large variability in soil properties and landscape *** plots were located under conditions where preplant N fertilization reduced or avoided temporary N shortages for some plants but did not reduce for other plants early in the *** measured corn heights to the youngest leaf collar,stages of growth and chlorophyll meter readings (CMRs). The added N advanced growth stages as well as increased corn heights and CMRs at any given *** effects on corn heights,growth stages and ear weights were statistically significant (Pcorn growth could help to define N deficiency more precisely and to improve the accuracy of diagnosing N status in production agriculture.

关键词： chlorophyll corn fertilizer growth stage nitrogen deficiency

An Image-Based Diagnostic Expert System for corn Diseases

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Agricultural Sciences in China 2010年第8期9卷 1221-1229页

作者： LAI Jun-chen MING Bo LI Shao-kun WANG Ke-ru XIE Rui-zhi GAO Shi-ju Key Laboratory of Oasis Ecology Agriculture of Xinjiang Construction Crop/Research Center of Crop High-Yield Shihezi University Shihezi 832003 P.R. China Institute of Crop Science Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Production Ministry of Agriculture Beijing 100081 P.R.China

The annual worldwide yield losses due to pests are estimated to be billions of dollars. Integrated pest management （IPM） is one of the most important components of crop production in most agricultural areas of the world, and the effectiveness of crop protection depends on accurate and timely diagnosis of phytosanitary problems. Accurately identifying and treatment depends on the method which used in disease and insect pests diagnosis. Identifying plant diseases is usually difficult and requires a plant pathologist or well-trained technician to accurately describe the case. Moreover, quite a few diseases have similar symptoms making it difficult for non-experts to distinguish disease correctly. Another method of diagnosis depends on comparison of the concerned case with similar ones through one image or more of the symptoms and helps enormously in overcoming difficulties of non-experts. The old adage ＇a picture is worth a thousand words＇ is crucially relevant. Considering the user＇s capability to deal and interact with the expert system easily and clearly, a webbased diagnostic expert-system shell based on production rules （i.e., IF 〈 effects 〉 THEN 〈 causes 〉） and frames with a color image database was developed and applied to corn disease diagnosis as a case study. The expert-system shell was made on a 32-bit multimedia desktop microcomputer. The knowledge base had frames, production rules and synonym words as the result of interview and arrangement. It was desired that 80% of total frames used visual color image data to explain the meaning of observations and conclusions. Visual color image displays with the phrases of questions and answers from the expert system, enables users to identify any disease, makes the right decision, and chooses the right treatment. This may increase their level of understanding of corn disease diagnosis. The expert system can be applied to diagnosis of other plant pests or diseases by easy changes to the knowledge base.

关键词： expert system disease diagnosis disease image corn

Estimating Fraction of Photosynthetically Active Radiation of corn with Vegetation Indices and Neural Network from Hyperspectral Data

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Chinese Geographical Science 2012年第1期22卷 63-74页

作者： YANG Fei ZHU Yunqiang ZHANG Jiahua YAO Zuofang The State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China The Laboratory of Remote Sensing and Climate Information Chinese Academy of Meteorological Sciences Beifing 100081 China The Beijing National Technology Transfer Center of Chinese Academy of Sciences Beijing 100086

The fraction of photosynthetically active radiation （FPAR） is a key variable in the assessment of vegetation productivity and land ecosystem carbon cycles. Based on ground-measured corn hyperspectral reflectance and FPAR data over Northeast China, the correlations between corn-canopy FPAR and hyperspectral reflectance were analyzed, and the FPAR estimation performances using vegetation index （VI） and neural network （NN） methods with different two-band-combination hyperspectral reflectance were investigated. The results indicated that the corn-canopy FPAR retained almost a constant value in an entire day. The negative correlations between FPAR and visible and shortwave infrared reflectance （SWIR） bands are stronger than the positive correlations between FPAR and near-infrared band re- flectance （NIR）. For the six VIs, the normalized difference vegetation index （NDVI） and simple ratio （SR） performed best for estimating corn FPAR （the maximum R2 of 0.8849 and 0.8852, respectively）. However, the NN method esti- mated results （the maximum Rz is 0.9417） were obviously better than all of the VIs. For NN method, the two-band combinations showing the best corn FPAR estimation performances were from the NIR and visible bands; for VIs, however, they were from the SWIR and NIR bands. As for both the methods, the SWIR band performed exceptionally well for corn FPAR estimation. This may be attributable to the fact that the reflectance of the SWIR band were strongly controlled by leaf water content, which is a key component of corn photosynthesis and greatly affects the absorption of photosynthetically active radiation （APAR）, and makes further impact on corn-canopy FPAR.

关键词： hyperspectral remote sensing corn FPAR vegetation index neural network