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Simple nonlinear model for the relationship between maize yield and cumulative water amount

Journal of Integrative Agriculture 2017年第4期16卷 858-866页

作者： LIU Cheng SUN Bao-cheng TANG Huai-jun WANG Tian-yu LI Yu ZHANG Deng-feng XIE Xiao-qing SHI Yun-su SONG Yan-chun YANG Xiao-hong LI Jian-sheng Maize Research Center China Agricultural University Institute of Grain Crops Xinjiang Academy of Agricultural Sciences Institute of Crop sciences Chinese Academy of Agricultural Sciences

Both the additive and multiplicative models of crop yield and water supply are polynomial equations, and the number of parameters increases linearly when the growing period is specified. However, interactions among multiple parameters occasionally lead to unreasonable estimations of certain parameters, which were water sensitivity coefficients but with negative value. Additionally, evapotranspiration must be measured as a model input. To facilitate the application of these models and overcome the aforementioned shortcomings, a simple model with only three parameters was derived in this paper based on certain general quantitative relations of crop yield （Y） and water supply （W）. The new model, Y/Y-W＊/（W＊＋w＊）, fits an S or a saturated curve of crop yield with the cumulative amount of water. Three parameters are related to biological factors： the yield potential （Y＊）, the water requirement to achieve half of the yield potential （half-yield water requirement, wh）, and the water sensitivity coefficient （k）. The model was validated with data from 24 maize lines obtained in the present study and 17 maize hybrids published by other authors. The results showed that the model was well fit to the data, and the normal root of the mean square error （NRMSE） values were 2.8 to 17.8% （average 7.2%） for the 24 maize lines and 2.7 to 12.7% （average 7.4%） for the 17 maize varieties. According to the present model, the maize water-sensitive stages in descending order were pollen shedding and silking, tasselling, jointing, initial grain filling, germination, middle grain filling, late grain filling, and end of grain filling. This sequence was consistent with actual observations in the maize field. The present model may be easily used to analyse the water use efficiency and drought tolerance of maize at specific stages.

关键词： yield water model maize water sensitivity drought tolerance

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Transcriptomes of early developing tassels under drought stress reveal differential expression of genes related to drought tolerance in maize

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Journal of Integrative Agriculture 2018年第6期17卷 1276-1288页

作者： WANG Nan LI Liang GAO Wen-wei WU Yong-bo YONG Hong-jun WENG Jian-feng LI Ming-shun ZHANG De-gui HAO Zhuan-fang LI Xin-hai Institute of Crop sciences Chinese Academy of Agricultural Sciences College of Agriculture Xinjiang Agricultural University

Tassel, the male reproductive organs in maize, its development is adversely affected by drought during tasseling. To determine drought tolerance mechanisms of tassel differentiation at transcriptome level, RNA-Seq was performed using RNA of early developing tassel from 10 maize inbred lines under well-watered （control） and drought-stressed conditions, respectively. Results showed that the most active pathway for drought stress in maize were related to metabolic regulation at RNA level. And some genes, encoding enzymes involved in carbohydrate and lipid metabolism, were significantly down-regulated in drought-stressed plants. While, the transcription factors and genes, encoding catabolic or degradative enzymes, were over-expressed in maize early developing tassels under drought-stressed conditions, and among them, the transcripts of genes encoding exon-junction complexes involved in ＇RNA transcript＇ and ＇mRNA surveillance＇ pathways were significantly affected by drought stress. In addition, many other genes related to drought stress showed transcriptional changes at the later period of stress.

关键词： Zea mays L. early developing tassel transcriptome drought tolerance

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The trade margins of Chinese agricultural exports to ASEAN and their determinants

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Journal of Integrative Agriculture 2018年第10期17卷 2356-2367页

作者： SUN Zhi-lu LI Xian-de Institute of agricultural Economics and Development Chinese Academy of Agricultural Sciences

How do Chinese agricultural exports to ASEAN（Association of Southeast Asian Nations） evolve？ And what factors affected the evolution pattern？ This study measures the trade margins of Chinese agricultural exports to ASEAN by utilizing the 2000-2015 Harmonized System＇s six-digit agricultural trade data, and further analyzes their determinants by developing an augmented gravity model of international trade. The results indicate that, the main growth source of Chinese agricultural exports to ASEAN has shifted from the extensive margin before the formal establishment of CAFTA（China-ASEAN Free Trade Area） in 2010 to the intensive margin since the formal establishment of CAFTA, but changes in Chinese agricultural exports to ASEAN have always mainly depended on the intensive margin. Since the formal establishment of CAFTA, the evolution pattern of Chinese agricultural exports to ASEAN has shifted from ＂more varieties, low price, and small quantity＂ to ＂less varieties, high price, and large quantity＂. Relative economic scale, relative population scale, capacity of agricultural export, trade integration, global financial crisis, and common border significantly affect the trade margins of Chinese agricultural exports to ASEAN.

关键词： China agricultural product ASEAN trade margins

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Do large-scale farmers use more pesticides? Empirical evidence from rice farmers in five Chinese provinces

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Journal of Integrative Agriculture 2020年第2期19卷 590-599页

作者： QIN Shi-le LU Xin-ye Institute of agricultural Economics and Development Chinese Academy of Agricultural Sciences

It is of great theoretical and practical significance to understand the rules of the differences in pesticide use behaviors between large-scale and small-scale farmers,so as to regulate the behavior of farmers differently and improve the quality and safety of *** overall pesticide use behavior of large-scale farmers was characterized by large doses and high application frequency,while that of small-scale farmers was characterized by small doses and low application *** econometric test showed that(i)the proportion of staple food ration has a significant negative impact on the single dose exceeding the standard and pesticide application frequency of small-scale farmers,and the increase of the proportion of staple food ration will reduce the demand among small-scale farmers for pesticides;(ii)yield effect has a greater impact on the frequency of pesticide application by large-scale farmers,and the large yield effect will increase the frequency of pesticide application among large-scale ***,in pesticide use behaviors,large-scale farmers should reduce pesticide quantity and increase efficiency,while small-scale farmers improve the level of plant protection.

关键词： pesticide use behavior rice farmers scale management

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Breaking the structural symmetry of active sites in zeolite imidazolate framework for enhanced CO2 photoreduction

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Science China Chemistry 2025年

作者： Yupeng Han Yayu Yan Qiaohong Li Xin Wu Fei Wang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of sciences College of Chemistry Fuzhou University

Adjusting the structure and composition of active sites is a highly effective method for activating linear ***, precise control of interfacial chemistry within molecular-scale environments presents a significant challenge in heterogeneous catalysis. In our study, we present symmetry-broken Mo-O-Co triple-atom active sites within the hybrid zeolite imidazole framework HZIF-CoMo. These sites disrupt the electronic balance and create a weak built-in electric field, thus promoting photocatalytic CO2reduction. The CO yield over HZIF-CoMo is improved to 3.1 mmol g-1h-1, which is over four times higher than the parent cobalt-imidazole framework MAF-6-Co. Both experimental and theoretical studies indicate that electronic modulation through the symmetry-breaking Mo-O-Co moiety acts as an organizing knob to accelerate charge separation and result in more carriers participating in the catalytic reaction. This work provides important insights into optimizing site-related electronic structures for targeted photocatalytic reactions.

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Traffic safety helmet wear detection based on improved YOLOv5 network

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Optoelectronics Letters 2025年第1期21卷 35-42页

作者： GUI Dongdong SUN Bo College of Software Southeast University Quanzhou Equipment Research Centre Haixi Institute Chinese Academy of Sciences

Aiming at the problem that the current traffic safety helmet detection model can't balance the accuracy of detection with the size of the model and the poor generalization of the model, a method based on improving you only look once version 5(YOLOv5) is proposed. By incorporating the lightweight Ghost Net module into the YOLOv5 backbone network, we effectively reduce the model size. The addition of the receptive fields block(RFB) module enhances feature extraction and improves the feature acquisition capability of the lightweight model. Subsequently, the high-performance lightweight convolution, GSConv, is integrated into the neck structure for further model size compression. Moreover, the baseline model's loss function is substituted with efficient insertion over union(EIoU), accelerating network convergence and enhancing detection precision. Experimental results corroborate the effectiveness of this improved algorithm in real-world traffic scenarios.

关键词： Traffic control

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Effects of potassium deficiency on photosynthesis and photoprotection mechanisms in soybean(Glycine max(L.)Merr.)

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Journal of Integrative Agriculture 2015年第5期14卷 856-863页

作者： WANG Xiao-guang ZHAO Xin-hua JIANG Chun-ji LI Chun-hong CONG Shan WU Di CHEN Yan-qiu YU Hai-qiu WANG Chun-yan College of Agronomy Shenyang Agricultural University Institute of Crop Research Liaoning Academy of Agricultural Sciences Institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Potassium is an important nutrient element requiring high concentration for photosynthetic *** potassium deficiency in soil could inhibit soybean（Glycine max（L.） Merr.） photosynthesis and result in yield *** on the photosynthetic variations of the different tolerant soyben varieties should provide important information for high yield tolerant soybean breeding *** representative soybean varieties Tiefeng 40（tolerance to K^＋ deficiency） and GD8521（sensitive to K^＋ deficiency） were hydroponically grown to measure the photosynthesis,chlorophyll fluorescence parameters and Rubisco activity under different potassium *** the K-deficiency stress time extending,the net photosynthetic rate（Pn）,transpiration rate（Tr） and stomatal conductance（Gs） of GD8521 were significantly decreased under K-deficiency condition,whereas the intercellular CO2 concentration（Ci） was significantly *** a contrast,the variations of Tiefeng 40 were almost little under K-deficiency condition,which indicated tolerance to K^＋ deficiency variety could maintain higher efficient *** the 25 th d after treatment,the minimal fluorescence（F0） of GD8521 was significantly increased and the maximal fluorescence（Fm）,the maximum quantum efficiency of PSII photochemistry（F√Fm）,actual photochemical efficiency of PSII（φ（PSII））,photochemical quenching（qp）,and electron transport rate of PSII（ETR）were significantly decreased under K^＋ deficiency *** addition,the Rubisco content of GD8521 was significantly decreased in *** is particularly noteworthy that the chlorophyll fluorescence parameters and Rubisco content of Tiefeng 40 were unaffected under K^＋ deficiency *** the other hand,the non-photochemical quenching（qN） of Tiefeng 40 was significantly *** dry matter weight of Tiefeng 40 was little affected under K^＋ deficiency *** indicated that Tiefeng 40 could avoid or relieve the destruction of PSII caused

关键词： photosynthesis photosynthetic soybean Rubisco potassium Glycine stomatal PSII transpiration chlorophyll

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Differential responses of short-term soil respiration dynamics to the experimental addition of nitrogen and water in the temperate semi-arid steppe of Inner Mongolia, China

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Journal of Environmental sciences 2014年第4期26卷 834-845页

作者： Yuchun Qi Xinchao Liu Yunshe Dong Qin Peng Yating He Liangjie Sun Junqiang Jia Congcong Cao Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences University of the Chinese Academy of sciences Institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

We examined the effects of simulated rainfall and increasing N supply of different levels on CO2 pulse emission from typical Inner Mongolian steppe soil using the static opaque chamber technique, respectively in a dry June and a rainy August. The treatments included NH4NO3 additions at rates of 0, 5, 10, and 20 g N/（***） with or without water. Immediately after the experimental simulated rainfall events, the CO2 effluxes in the watering plots without N addition （WCK） increased greatly and reached the maximum value at 2 hr. However, the efflux level reverted to the background level within 48 hr. The cumulative CO2 effluxes in the soil ranged from 5.60 to 6.49 g C/m2 over 48 hr after a single water application, thus showing an increase of approximately 148.64% and 48.36% in the efftuxes during both observation periods. By contrast, the addition of different N levels without water addition did not result in a significant change in soil respiration in the short term. Two-way ANOVA showed that the effects of the interaction between water and N addition were insignificant in short-term soil COz efftuxes in the soil. The cumulative soil CO2 fluxes of different treatments over 48 hr accounted for approximately 5.34% to 6.91% and 2.36% to 2.93% of annual C emission in both experimental periods. These results stress the need for improving the sampling frequency after rainfall in future studies to ensure more accurate evaluation of the grassland C emission contribution.

关键词： soil respiration short-term response N addition simulated rainfall temperate steppe

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Applying a new method for direct collection, volume quantification and determination of N_2 emission from water

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Journal of Environmental sciences 2015年第1期27卷 217-224页

作者： Xinhong Liu Yan Gao Honglian Wang Junyao Guo Shaohua Yan Institute of agricultural Resources and Environment Jiangsu Academy of Agricultural Sciences College of Resources and Environmental Science Nanjing Agricultural University

The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al.（2013） developed a new method using a bubble trap device to collect gas samples from waters. However, the determination accuracy of sampling volume and gas component concentration was still debatable. In this study, the method was optimized for in situ sampling, accurate volume measurement and direct injection to a gas chromatograph for the analysis of N2 and other gases. By the optimized new method, the recovery rate for N2 was 100.28% on average; the mean coefficient of determination（R2） was 0.9997; the limit of detection was 0.02%. We further assessed the effects of the new method, bottle full of water, vs. vacuum bag and vacuum vial methods, on variations of N2 concentration as influenced by sample storage times of 1,2, 3, 5, and 7 days at constant temperature of 15°C, using indices of averaged relative peak area（%） in comparison with the averaged relative peak area of each method at 0 *** indices of the bottle full of water method were the lowest（99.5%–108.5%） compared to the indices of vacuum bag and vacuum vial methods（119%–217%）. Meanwhile, the gas chromatograph determination of other gas components（O2, CH4, and N2O） was also accurate. The new method was an alternative way to investigate N2 released from various kinds of aquatic ecosystems.

关键词： New method N2 Ebullition collection Direct injection Gas chromatograph

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Biosorption of La^(3+) and Ce^(3+) by Agrobacterium ***1

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Journal of Rare Earths 2011年第3期29卷 265-270页

作者：徐淑霞张世敏陈克韩锦峰刘华山吴坤 College of Life sciences Henan Agricultural University College of Agronomy Henan Agricultural University

The Agrobacterium ***1 was isolated from the soil and used to adsorb rare earth ions La3＋ and Ce3＋.The results showed that the pretreatments of Agrobacterium ***1 did not enhance the adsorption of La3＋ and Ce3＋.The pH,temperature,time and bacterial age affected the dynamics of adsorption of La3＋ and Ce3＋.The optimum adsorption conditions for Agrobacterium ***1 were as follows：15 mg/L La3＋ of initial concentration,10 mg/L Ce3＋,300 mg/L（dry ***） biomass for sorption,6.8 pH,30 oC temperature,150 r/min rotational speed,2 h adsorption time and 28 h bacterial *** adsorption kinetics of La3＋ and Ce3＋ for Agrobacterium ***1 followed the pseudo-second order equation.

关键词： biosorption rare earth elements(REEs) Agrobacterium sp.HN1

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