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- Abstract：In order to explore the mechanism of maize yield increase by ear grain number after spraying plant fungicides ‘Cabrio' and ‘Opera', this study analyzed the dry matter accumulation and yield components of corn under low density(67 500 and 75 000 plants/hm2)and high density(90 000 plants/hm2)conditions from 2011 to 2015. The results show that: The application of plant fungicide at 9 leaf stage can increase yield at different densities. The yield increase was 8. 83% at high density, which is more significant. PCA analysis showed that the yield increase was significantly correlated with grain number per ear and 1 000-grain weight, but mainly depended on grain number per ear. The increase of grain number per ear was mainly related to the decrease of seed abortion and the significant increase of seed setting rate. After the application of fungicide, the seed abortion rate of low density and high density treatment decreased by 30. 20% and 36. 60%, respectively. The decrease of seed abortion rate was related to the increase of Pn and dry matter accumulation. Further analysis of the Pn of the three leaves(ear leaf, upper ear leaf and lower ear leaf)of maize plants showed that the average Pn increased by 49. 10% at the low density spinning stage, and the average Pn at the high density filling stage increased by 43. 49%. From the data analysis of dry matter increase in V6(6th leaf stage)-R1(silking stage), it was obvious that after spraying fungicide, the correlation between dry weight increment and panicle grain number(r=0. 669*)was higher than that of water treatment(r=0. 517*), showing significant correlation. In conclusion, the application of fungicides at the 9th leaf stage of maize could enhance the photosynthetic capacity after flowering, improve the accumulation of dry matter after flowering, promote the transport of matter to the grain, reduce the grain abortion, and thus significantly increase the seed setting rate and the number of grains per ear. At the same time, it is beneficial to delay the senescence of late plant and increase the grain weight.Keywords：maize;fungicides;kernel number;grain weight;yield4|13|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the changes and sustainability of water resources in Hebei Province, the changes of the water resources were calculated, and the water ecological footprint and water ecological carrying capacity models were constructed. The water resources supply and demand status in Hebei Province form 2004 to 2018 were analyzed. The results showed that: Compared with the period from 2004 to 2011, the inter-annual variation increased from 2012 to 2018, while the mean value of total water resources did not change much. In terms of the water use structure, the water using was steadily decreasing. Although the proportion of agricultural water use was decreasing year by year, it still accounted for a large proportion of the water usage, which resulted in a total water resource deficit of 618. 28 billion m3 from 2004 to 2018. From the point of view of the water supply structure, the proportion of above ground water supply increased year by year, and the below ground water was still the main water supply, which led to the continuous increase of groundwater depth. The ecological footprint of water resources showed that: The overall ecological footprint of water resources in Hebei Province for many years displayed a downward trend, and the carrying capacity showed a slowly rising trend. In conclusion, the water pressure in Hebei Province is still high, but it is developing toward a positive direction. Scientific and effective ways of saving water are important to promote the sustainable development of water resources in Hebei Province. A variety of water-saving measures should be taken together to speed up the construction of a new water use and supply structure, and reach the new balance of water resource supply and demand as soon as possible.Keywords：water resources;agricultural water;water resources deficiency;water conservation;structure of water consumption6|10|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Under salt and drought stress, the effects of different far red light irradiation scenarios on rice seed germination and seedling growth were investigated. Rice was selected as the experimental object. NaCl solution and polyethylene glycol(PEG)were set as salt stress and drought stress, respectively. Under the condition of far red light, the critical values of drought and salt damage for rice growth and development were obtained. Then a cross stress of salt and drought was set according to the threshold value of drought and salt damage. There was no far red light irradiation in the control group. The experimental groups of intermittent far red light irradiation for 1-4 times and single irradiation for 5, 10, 15 and 20 minutes were designed, respectively. The germination rate, germination potential, germination index, root length, plant height, stem diameter, dry matter quantity and chlorophyll content of rice seeds were measured. The effects of far red light irradiation on rice seed germination and seedling growth under salt and drought stress were compared. The results showed that: The drought threshold of PEG solution was 18%, which was expressed by mass fraction. The drought threshold of NaCl solution salt stress was 0. 05 mol/L, which was expressed by the concentration of NaCl solution. The salt and drought environment was set as the above threshold. When the far red light irradiation times are increased, the germination rate, germination potential and germination index of rice increased by 9. 1%, 10. 5% and 25. 7%, the root length, plant height and stem diameter of rice increased by 29. 2%, 7. 2% and 8. 9%, and the dry matter quantity and chlorophyll content of rice increased by 50. 6% and 85. 8%. When the duration of single irradiation is prolonged, the germination rate, germination potential and germination index of rice increased by 10. 2%, 10. 5% and 34. 3%, the root length, plant height, stem diameter of rice increased by 91. 6%, 14. 4% and 7. 8%, and the dry matter quantity and chlorophyll content of rice increased by 48. 8% and 68. 1%. Therefore, increasing the number of far red light irradiation times and single irradiation time can significantly promote rice seed germination and seedling growth.Keywords：rice;salt drought stress;far red light;LED light source11|14|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the effect of cis-abienol synthesis gene NtCPS2 on terpenoid metabolic pathways, CRISPR/Cas 9 gene editing technology was used to edit the tobacco cis-abienol synthesis gene NtCPS2. The homozygous mutant plants were screened, and named as ‘8306' gene-editing series. The content and the key synthesis genes of cis-abienol and gibberellin were compared between the ‘8306' gene-editing series(T2-26, T2-45, T2-48)and the wild type(WT). Compared with WT, the cis-abienol content in the ‘8306' gene-editing series was decreased by 86. 20%, the gibberellin content was increased by 27. 05% on average. The key gene′s expression in the synthesis pathway of cis-abienol was significantly reduced. In the gibberellin synthesis pathway, the expression level of GA20ox, the key gene of positive regulation, was significantly increased. At the same time, the expression level of GA2ox, the key gene of negative regulation, was significantly decreased. Moreover, the expression level of DXR, the key gene of GGPP synthesis, was increased. In conclusion, the NtCPS2 gene not only affected the labdane diterpenes metabolic pathway and effectively reduced cis-abienol content, but also affected the gibberellin metabolism and increased gibberellin content.Keywords：tobacco;the ‘8306' edited strains;NtCPS;2;cis-abienol;gibberellin9|13|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the physiological characteristics of cucumber, and ensure its high-yield cultivation, pot experiments were conducted at seedling and adult plant stages. Using sterile water as control, 103, 104, 105, 106 and 107 CFU/g of Trichoderma asperellum agents were respectively applied. The effects of different T. asperellum agents application amounts on the morphological formation, physiological indexes of cucumber seedlings, quality and yield traits were monitored. The results showed that: Application of T. asperellum agents effectively improved the plant height, stem diameter, leaf area, fresh weight of whole plant, dry weight of whole plant, root shoot ratio and strong seedling index of cucumber seedlings. The treatment of 106 CFU/g had the best promoting effect on the morphological formation and material accumulation of cucumber seedlings. Application of T. asperellum agents improved the physiological characteristics of cucumber seedlings including chlorophyll content, root activity, nitrate nitrogen content, nitrate reductase activity, soluble sugar content and soluble protein content. Application of T. asperellum agents also improved the formation of cucumber quality and yield, and the treatment of 106 CFU/g T. asperellum agents had the best promoting effect on the formation of cucumber quality and the yield, soluble sugar, vitamin C, soluble protein, soluble solid and yield of cucumber fruit increased by 78. 43%, 31. 55%, 38. 47%, 8. 63% and 26. 20%, respectively, compared with CK under 106 CFU/g T. asperellum agents. In conclusion, T. asperellum agents can improve the physiological characteristics of cucumber seedlings, promote the growth of seedlings, increase the yield and qualities of cucumber fruit, and the 106 CFU/g of T. asperellum agents is the most effective. This study provides technical references for the development and utilization of T. agents and the high quality cultivation of cucumber.3|15|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The objective of this study was to calculate the resistant coefficients of different simplified lying pig geometric models and analyze the differences. In this study, the validated CFD model was applied to investigate the effect of four different simplified geometric models of lying pigs on the resistant coefficients in X, Y and Z directions in pig occupied zone for porous media modeling. The four geometric models were simplified pig model, ellipsoid model, half ellipsoid model, and half cylinder model. The influence of the four geometric models on the relationship between wind speed and pressure distribution in the pig occupied zone was also analyzed. The results showed that the inertial resistant coefficients of ellipsoid model were closer to the simplified pig model than the half ellipsoid model and the half cylinder model. The relative errors of inertial resistant coefficients between ellipsoid model and simplified pig model in X, Z, and Y directions were -4. 0%, -12. 2% and 14. 7%, respectively. In addition, the wind speed and pressure distribution of ellipsoid model and simplified pig model were basically consistent. Therefore, the ellipsoid model instead of the simplified pig model can not only ensure the accuracy, but also effectively improve the calculation efficiency.Keywords：lying pig model;porous media model;resistant coefficient;computational fluid dynamics(CFD)5|10|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：This experiment aimed to study the effects of long-term feeding of citrus extract on blood biochemical indexes, antioxidant capacity, immune function and free amino acids of finishing pigs. A total of 108 56-day 19. 73±0. 39 kg Duroc×Landrace×Large White pigs, both barrows and females, were assigned to 3 dietary treatments. The blank group was fed the basic diet, the antibiotic group was fed the basal diet with 75 g/t chlortetracycline, and the citrus extract group was fed the basic diet with 250 mL/t citrus extract(56-112 d)and 200 mL/t citrus extract(113-194 d). The total plasma cholesterol, triglyceride and other biochemical indexes, and malondialdehyde, total antioxidant capacity and other antioxidant indicators were determined by spectrophotometry. The content of free amino acids in plasma was determined by amino acid analyzer. The immune indexes such as interleukin and immunoglobulin were determined by enzyme-linked immunosorbent assay. The results showed that: 1)Compared with the blank group, the plasma urea nitrogen content of the citrus extract group and antibiotic group were significantly decreased by 19. 66% and 15. 53%(P<0. 05), respectively; compared with the antibiotic group, the total cholesterol content in the citrus extract group was decreased(0. 05≤P<0. 10). 2)Compared with the blank group, citrus extract significantly increased the total antioxidant capacity of plasma(P<0. 05). 3)Compared with the blank group, the serum IgA concentration in the antibiotic and citrus extract groups increased by 13. 17% and 15. 50%, respectively(P<0. 05), and the IgM concentration in the antibiotic group decreased significantly(P<0. 05). 4)Compared with the blank and antibiotic groups, the level of plasma leucine in the citrus extract group was significantly increased(P<0. 05), and the proline level tended to increase(0. 05≤P<0. 10); compared with the blank group, the citrus extract group significantly increased the contents of asparagine, glutamate and alanine(P<0. 05), which was similar to the antibiotic group. In short, the long-term feeding of citrus extract can reduce plasma urea nitrogen content, and improve the blood antioxidant capacity, immune function and free amino acids level of finishing pigs.Keywords：citrus extract;pig;antioxidant capacity;immune function;free amino acid1|12|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to study the changes of physical and chemical indicators and antioxidant properties of donkey meat during chilled aging, 10 Dezhou donkeys were selected. After slaughtering, longissimus dorsi were harvested and chilled aging at 0-4 ℃ for 72 h. The physicochemical and antioxidant indexes were determined at 0, 1, 6, 24, 48 and 72 h respectively. The results showed that pH of donkey meat changed significantly(P<0. 001)within 72 h chilled aging, and showed significant linear decrease with the extension of time(PL<0. 001), which was significantly lower than 1 and 6 h, and there was no significant difference after 24 h; The L* value of donkey meat had significant difference(P<0. 001)during 72 h chilled aging, and presented linear increasing change with acid excretion time(PL<0. 001). a* value first increased and then decreased during low temperature maturation(PQ<0. 001), which reached the maximum value at 6 h chilled aging. b* value did not change significantly(P=0. 141). TVB -N and AV values of donkey meat also did not change significantly during the period of 72 h chilled aging(P=0. 880, P=0. 857), which met the national standards for fresh meat. The PV value of donkey meat presented a linear increase with the extension of low temperature maturity time(PL<0. 001), which was significantly higher at 24 h than that of 0 and 1 h. There was no significant difference in TBARS content(P=0. 788). The content of -SH increased first and then decreased(PQ=0. 024). T-AOC, SOD, CAT and GSH-Px all presented the same linear decreasing trend(PL<0. 05), and decreased significantly after 48 h chilled aging(P<0. 05). In conclusion, the pH and color of donkey meat changed during 72 h low temperature ripening, and the antioxidant capacity decreased. Further research on the stability of meat color and the improvement of antioxidant capacity of donkey meat were needed.Keywords：donkey meat;chilled aging;physical and chemical indicator;antioxidant property5|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Milk fat is not only a key factor affecting the quality of fresh milk, but also the main target character of dairy cow breeding. In order to explore the theory and approach of milk fat formation and regulation, the epigenetic regulation of milk fat metabolism in ruminants by functional non-coding RNA was expounded by collecting the latest literature. The results showed that: 1)PPARγ is a crucial regulatory factor in the process of milk fat synthesis. In bovine, miR-29 s、miR-454、miR-34b and miR-27a all have binding sites with PPARγ, which respectively play important roles in promoter region or 3′-UTR, thus affecting the synthesis of BMECs TAG. 2)A variety of the target genes of microRNAs regulating goat milk fat metabolism come from peroxisome proliferation-activated receptor family, which suggests that this family plays a key regulatory role in goat milk fat synthesis and catabolism. 3)miR-27a is identified in ruminant including cattle and sheep by regulating PPAR γ to inhibit the synthesis of tag and the expression of lipid related genes. 4)There are relatively few studies on the regulation mechanism of milk fat metabolism by lncRNA and circRNA in ruminants. But it is clear that they focus on the regulation of milk fat by sponging microRNAs to indirectly regulating lipid-generating genes, which has a positive effect on gene expression. In conclusion, studies on the regulation of milk fat metabolism by lncRNA, circRNA and microRNA are still ongoing, and the specific mechanism remains to be further studied and explored to provide new ideas for the research on the regulation mechanism of milk fat in ruminants.Keywords：microRNA;lncRNA;circRNA;ruminants;milk fat5|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study was to compare miRNA expression profiles of sensitive and resistant strains of Haemonchus contortus, and to explore the regulatory mechanism between miRNA and albendazole resistance related genes of H. contortus. Illumina Hiseq2000 platform was used to sequence and construct the cDNA library. RNAhybrid, Miranda, TargetScan were used to predict the target gene of the sequenced data, and then their intersection was taken as the miRNA prediction result. Bioinformatics analysis softwares such as Bowtie, RepeatMasker, MIREAP, Rfam, miRbase, DAVID and authoritative database systems were used to screen differentially expressed miRNAs and miRNAs associated with drug resistance of H. contortus for target genes prediction. Target genes enriched by KEGG pathway and GO function and possible pathways involved in regulation were predicted and analyzed. The results showed that 294 miRNAs were differentially screened from sensitive and resistant strains, of which 113 were up-regulated and 181 were down-regulated. A total of 1 770 miRNA-mRNA pairs are negatively correlated with miRNA, including 274 differentially expressed miRNAs and 603 differentially expressed mRNAs. The target genes of the differentially expressed miRNA were annotated to 1 430 GO terms and 327 KEGG pathways, and enriched to FoxO signaling pathway, mTOR signaling pathway, PI3K-Akt signaling pathway and other resistance-related pathways. In summary, through the analysis of miRNA expression profile and miRNA-mRNA targeting analysis, it was found that there were significantly different miRNA and the corresponding target genes between the sensitive and resistant strains of H. contortus. The target genes in some drug-resistance related pathways and the pathways in which the significantly different target genes were located, screened and analyzed. This study provided references for the further exploration of the genes and regulatory molecules related to drug resistance of H. contortus.Keywords：Haemonchus contortus;albendazole;drug resistance;transcriptome;miRNA2|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Soil-borne fungal diseases have the characteristics of wide distribution, rapid spread and great harm, which have become a worldwide problem. Chemical fungicides have always been considered an important means to control soil-borne fungal diseases. However, the long-term extensive use of chemical fungicides has not only caused pesticide residues and increased resistance to pathogens, but also poses a huge threat to food security, food safety and environmental safety. It seriously restricts the healthy and sustainable development of agriculture. The rhizosphere micro-ecological environment is closely connected to the soil micro-domain and interacts with plant roots. It is an ecosystem built by plants themselves, which is beneficial to plant health and growth. In-depth exploration of the rhizosphere micro-ecological mechanism of the occurrence of crop soil-borne fungal diseases is conductted to find safe and effective control ways from the aspects of rhizosphere microorganisms, environmental factors, and disease-inhibiting substances. This article focuses on the harm caused by soil-borne fungal diseases, the rhizosphere micro-ecological mechanism of fungal soil-borne disease occurrence, and the research progress on biological control of soil-borne fungal diseases, etc. , and aims to provide reference for the research of green prevention and control of soil-borne fungal diseases.Keywords：soil-borne fungal diseases;soil microorganisms;rhizosphere micro-ecological;biological control11|21|19<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The effects of different peanut shell biochar addition ratio on greenhouse gas and NH3 emissions during swine manure composting were investigated to provide scientific basis for nitrogen conservation and greenhouse gas emissions reduction. In this study, an experiment with peanut shell biochar addition rates of 0, 3%, 6% and 9% was conducted to study greenhouse gas(GHG)and NH3 emission and its correlation with environmental factors during swine manure composting using static forced-air composting boxes. The results showed that peanut shell biochar addition increased the high temperature duration of swine manure composting, the pH of composts increased by 0. 09-0. 13 units, and the EC increased by 11. 7%-50. 6%. The CO2, CH4, and N2O emission rates increased first and then decreased with the increase of the composting time, and had a significant correlation with pH. With the increase of peanut shell biochar addition, the CO2 emission rate during swine manure composting first increased and then decreased. The average CO2 emission rate of 3% peanut shell biochar treatment was the highest, and increased by 12. 9% than that of control. Both N2O emission and NH3 volatilization of 9% peanut shell biochar treatment were the lowest, which decreased by 12. 5% and 29. 9%, respectively. In conclusion, during the entire composting process, the addition of peanut shell biochar reduced the cumulative emissions of N2O and CH4. The emission reduction effect increased with the increase of the peanut shell biochar.Keywords：swine manure;composting;biochar;greenhouse gas;NH;37|14|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Using Mono-Window algorithm, supervised classification and logistic regression model, Wuhan, a typical metropolis in the Yangtze River economic belt, was taken as the research area. The spatial and temporal evolution characteristics of heat island effect and its relationship with land use types and different construction land types were quantitatively studied. The main conclusions are as follows: 1)In terms of time series, the area and intensity of Wuhan heat island have a tendency to gradually increase with time; from the perspective of spatial distribution pattern, Wuhan heat island gradually gathers in the central urban area and spreads around it. 2)The distribution of construction land is consistent with that of heat island. The expansion of construction land can obviously aggravate the heat island effect, and green space and water bodies have a significant mitigation effect on the heat island effect. 3)Transportation contribute the most to the increase of heat island effect. The industrial and mining storage land, public management and public service land can also lead to the enhancement of the heat island effect, while the residential and commercial land have not shown obvious enhancement. Therefore, in order to alleviate the urban heat island effect, on the macro level, it is necessary to ensure a certain proportion of urban green space to slow down the temperature rise; on the micro level, it is necessary to reasonably arrange various types of construction land and build small patches of green space and pocket parks in urban planning.Keywords：heat island effect;land use;construction land;logistic regression;Wuhan4|13|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to track the development trend of soil conditioner and understand the characteristics of current soil conditioner patents, the patents published from 2011 to present obtained from the DII(Derwent Innovations Index)patent database were analyzed from the aspects of the raw materials and functions using the bibliometric method. The results showed that a total of domestic and foreign 1 997 patents were published at home and abroad from 2011 to 2020 and the patents from China accounted for 84%. The raw materials adopted in Chinese patents mainly included the agricultural wastes, chemical agents and natural minerals, and their functions mainly include the improvement of soil structure and crop yield, amendment of the saline soil and heavy metal passivation. Taking the function of heavy metal passivation as an example, this kind of patents accounted the highest proportion of 17. 3% from 2019 to 2020. The research development of new materials of soil conditioner, innovation of preparation technology and immobilization mechanisms, and combination of material functions are recommended in this study as the future development trends.Keywords：soil conditioner;patent;raw material;function;mechanism of action8|12|6<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Soil is the main source of the magnesium nutrient for plants, however magnesium deficiency is wildly existing in soil in southern China. In this study, Langmuir, Temkin and Freundlich adsorption isotherm models are selected to simulate the result of magnesium adsorption experiments with four types of typical soil samples in China(red soil, latosol yellow brown and meadow soil), and the influence of organic matter and particle size on magnesium adsorption are further studied. The results show that: 1)The Langmuir adsorption isotherm model effectively fits the soil magnesium adsorption data; 2)The amount of magnesium adsorption in soil with organic matter is significantly higher than that of eliminating organic matter, and magnesium adsorption in soil with a particle size of 1 mm is significantly stronger than that of soil samples with a particle size of 2 mm. 3)Meadow soil and latosol have the highest and lowest magnesium adsorption capacity, respectively. 4)The maximal magnesium adsorption(qmax)has a very significant positive correlation with soil pH, organic matter, cation exchange capacity and exchangeable magnesium ions(P<0. 01), and a significant positive correlation with soil particle size(P<0. 05). In summary, increasing organic matter and reasonably improving soil particle composition can significantly increase the amount of magnesium adsorption in the soil.Keywords：magnesium;organic matter;particle size;adsorption isotherm6|12|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the quality of Lycium barbarum L. dry products, the effects of different pretreatment methods(ultrasonic, permeating, hot blanching, ultrasonic + permeating group and ultrasonic + hot blanching group)on the quality of L. barbarum were studied. The contents of L. barbarum polysaccharides and the main antioxidant, color and sensory evaluation and microstructure of L. barbarum dry products by hot-air and far-infrared drying after different pretreatment were compared. The results showed that: 1)Under hot-air drying without pretreatment, the color of dried products was bright, the total color difference value was small, and the contents of total phenols and total flavonoids were the highest, and its antioxidant capacity was the best; The content of polysaccharide in far-infrared drying was the highest(793. 841 mg/g), and the microstructure was better and sensory score was higher. 2)In addition to ultrasonic+hot blanching pretreatment, the other four pretreatment methods are conducive to improve the sensory quality of dry products. Ultrasonic and hot blanching pretreatment can significantly shorten the drying time, improve the lightness value of the dried product, and can significantly improve the content of total flavonoids under the hot-air drying conditions. The osmotic pretreatment could significantly improve the content of polysaccharides and total phenols under far-infrared drying, and the color of dried products was better. In conclusion, the far-infrared drying under ultrasonic+osmotic pretreatment is the most suitable processing method for L. barbarum.6|11|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The number of wheat ears per unit area is an important indicator for estimating wheat yield. In view of the low efficiency and high subjectivity of traditional wheat ear counting methods, a density regression model based on the deep residual network is introduced into the field of wheat ear counting. It establishes the corresponding relation-ship between the original image and the density map, and determines the number of wheat ears in the image by the sum of the pixel values of the density map. The ResNet-16 model is proposed on the basis of improving the ResNet34 model. In view of the high complexity of the ResNet34 network, ResNet-16 model is used to increases the width of the residual block and reduces the depth of the ResNet34 network; In order to avoid distortion of true value density map and too fast gradient descent, correction factor δ and the expansion factor K are introduced. The results show that: The improved ResNet-16 model can obtain better prediction accuracy. Its mean absolute error is 2. 50, root mean square error is 3. 27, correlation coefficient R2 is 0. 973, and the counting accuracy rate reaches 94%. Compared with MCNN model, the accuracy of ResNet-16 is improved by 6%, which can achieve high efficiency and fast ear counting. The regression counting model based on deep residual network provides a new counting method for wheat ear counting.Keywords：wheat ear;counting;density map regression;residual network4|11|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to study the effects of the pig face recognition model on the face change recognition during finishing pigs' growth, this study used deep convolutional networks to investigate the relationship between facial changes during Large White finishing pigs' growth and the accuracy of recognition models. The results showed that: 1)Comparision of the results of four pre-trained pigface recognition models(DenseNet201, MobileNetV3_small, SeNet154 and Xception)in experiments discovered that the pig face recognition accuracy of SeNet154(98. 80% in validation set)was the highest, and was then selected as pig face recognition model in this study. 2)The model was trained using the data of first few days after experiment operated, and then tested by using the daily data of the next 6 days, respectively. It was found that the recognition accuracy of the model trained with the data of the first 4 days after the experiment operated was equivalent with that the model trained with the data of first 5 days, and was higher than the model trained with the data of the first 2 and 3 days. The recognition accuracies of the model trained with the data of the first 4 days were gradually decreased to test the daily data of next 6 days, and the recognition accuracies were 96. 74% and 84. 17% to test the data of the 5th day and 10th day, respectively. The reasons for the recognition accuracies decreasing were due to the growth of pig faces, illumination changes inside the pig house, and adhesion of stains. 3)The recognition accuracies of using the dynamic model updated daily with the data of 4 days before the tested day to recognize pig face data of the tested day were all above 95. 82%. Therefore, the deep convolutional network model has high recognition accuracy on pig face, and it can be used for finishing pig's facial recognition. Due to the finishing pigs grow fast, it is recommended that the pig face recognition model should be updated every day using the data of previous 4 days or more and the face images without less than 10 800 sets.Keywords：finishing pigs;pig face recognition;deep learning;convolutional neural network7|10|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To precisely forecast NH3 concentration in layer house, this study proposes a NH3 concentration prediction model based on two-stage attention mechanism and long short-term memory(LSTM). In order to validate the model, time series of carbon dioxide(CO2), oxygen(O2)and ammonia(NH3)volume fraction, particulate matter(PM2. 5)mass concentration, temperature and relative humidity in layer house in Shanghe County Shandong Province are collected and input to two-stage attention mechanism and LSTM base model. The results show that the model could predict NH3 concentration in layer house accurately. Under different window size T∈{2, 3, 4, 8}, the root mean square error(RMSE)are 0. 433 4, 0. 394 8, 0. 379 9 and 0. 405 1 μL/L, respectively; The mean absolute error(MAE)are 0. 267 4, 0. 262 9, 0. 228 9 and 0. 272 4 μL/L, respectively. The model performance in this research is better than the support vector regression(SVR), artificial neural network(ANN)and common LSTM without attention mechanism by RMSE and MAE showing that the model has great potential to be used in NH3 concentration prediction and control in layer house.Keywords：attention mechanism;long short-term memory neural network;recurrent neural network;encoder-decoder;layer house;ammonia concentration4|10|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A large amount of water is used in the process of livestock and poultry production. Water consumption can be assessed by the water footprint of livestock and poultry. Nowadays, with the demand for livestock and poultry products increasing, water consumption is also rising. Therefore, it is time to address the problem of global water stress. Evaluating the water consumption of livestock and poultry products production and analyzing the water consumption at different stages of production will help producers and consumers to identify the processes of maximum water consumption and adopt targeted strategies to improve water use efficiency. This paper introduces the current state of research on the water footprint of livestock and poultry products at home and abroad, and makes a comparative analysis of different methods for evaluating the water footprint of livestock and poultry products. Finally, this study looks forward to the development of the water footprint of livestock and poultry products. Proposes the following main measures to reduce the water footprint of livestock and poultry products. 1)reduce the water footprint of feed production; 2)improve the feed conversion efficiency; 3)manage water resources and improve the production performance of livestock and poultry animals; 4)change people's consumption habits.Keywords：livestock and poultry products;water footprint;virtual water;virtual water trade5|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to explore the impact of online reviews on the operation effect of fresh e-commerce, based on the theoretical framework of Information Adoption Model, a theoretical model is constructed to clarify how the online review influence the fresh products, and exploit the Python crawler to obtain the monthly cross-sectional data of all fresh mutton products on Taobao platform. The effect of online reviews on fresh agricultural products sales is analyzed by OLS method with robust standard error from the perspective of agricultural product sales volume. The direct and interactive effects of online-review number, online-review length, number of negative comments and visual comments on fresh e-commerce sales are discussed. The results show that the number of online reviews and visual reviews can significantly improve the fresh agricultural products sales, while the number of negative reviews tend to decrease the sales volume, and the length of reviews has no significant effect on sales. The analysis of interaction effect between online review features shows that negative reviews can weaken the positive effect of pictures and online-review numbers on sales volume, pictures can strengthen the positive effect of comment length on sales volume, and the negative effect of negative reviews can be neutralized by comment length to a certain extent. Therefore, the fresh e-commerce business should pay attention to the opinions reflected by the negative online reviews to avoid the repetition of these negative ones, and adopt reasonable measures to encourage consumers to comment, and write the evaluation with more pictures and words, which are all effective ways to facilitate trust and promote the fresh e-commerce sales.Keywords：online reviews;fresh e-commerce sales;information adoption;interaction effect4|10|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
How does home-owned agricultural machinery affect land transfer? An empirical analysis based on CFPS
Abstract：To explore the role of household-owned farm machinery on land transfer, based on the nationally representative CFPS2018 data, this study explores and examines how farmers' self-owned agricultural machinery affects land circulation land under the premise of controlling the socialized services of agricultural machinery. The results show that: 1)With the improvement of the household-owned agricultural mechanization, the lower the possibility of farmers transferring in land, the higher the possibility of transferring out land. 2)Using the moderating effect model, it is found that the household non-agricultural employment rate can significantly positively regulate the impact of own agricultural machinery on land circulation, the wage level of agricultural hired workers and uneven terrain could negatively regulate the impact of household-owned agricultural machinery on land circulation. However, the village traffic conditions cannot adjust the impact of own agricultural machinery on land circulation. 3)For farmers' land transfer behavior, the socialized service of agricultural machinery and self-owned agricultural machinery negatively inter-regulate their effects on land transfer, indicating that there is a certain competitive relationship and complementary relationship between family-owned agricultural machinery and socialized service of agricultural machinery. Therefore, the influence of family-owned agricultural machinery on land circulation cannot be ignored, and the influence of family-owned agricultural machinery on land circulation is regulated by external factors such as non-agricultural employment, labor cost, natural landscape and social services of agricultural machinery, which can enhance or weaken the influence of family-owned agricultural machinery on land circulation.Keywords：household-owned machinery;agricultural mechanization;land transfer out;land transfer in1|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27- Abstract：To explore how farmers make decisions when facing multiple green production technologies, this study uses a multivariate Probit model to analyze the observable determinants of different green production technologies(conservation tillage technology, green control techniques, and recycling of agricultural plastic film)based on cross-correlation error controlled, and the correlation among adopted technologies are investigated. The cross-technology correlation is estimated by using conditional probabilities and the average treatment effect method. The results show that: 1)Farmers with different resource endowments have certain technical choices for the technology of different attributes, but they do not necessarily adopt the technology of corresponding attributes. 2)Farmers' adoption of different green production technologies is interdependent, and there exist a strong positive correlation. Comparing the effects, the number of technologies that farmers adopt increase the probability of adoption, which results in a “superimposed effect”. The impact of the cross-technology correlation is heterogeneous. Therefore, this study proposes differentiated technology promotion strategies should be adopted according to farmers' resource endowments and technical attributes. And to improve the efficiency of green production technology promotion, the technical combination and the sequence of technology promotion should be arranged reasonably according to cross-technology correlation.Keywords：multivariate Probit model;green production technology;technology adoption;treatment effect8|10|8<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study was to promote a sound system of laws and regulations on crop straw burning control and comprehensive utilization in China, and to provide fundamental security for smooth progressing of burning control and constant improvement of comprehensive utilization. Current laws and regulations that contained explicit statements on crop straw burning control and comprehensive utilization were summarized at three levels, which were national laws, administrative and sectoral regulations, local regulations. Problems and deficiencies were analyzed and summarized. The results showed that the system of laws and regulations on crop straw burning control and comprehensive utilization has initially established. However, there some problems still existed in the system. These problems could be classified into 6 categories, e. g. the absence of higher-level special laws, the shortage of characteristic in local regulations, the poor feasibility, the deficiency of regulatory measures for non-prohibition areas, the inadequacy of strength of incentives and penalties, and incompetence of monitoring and law enforcement capacity categories. In view of problems mentioned above and learning from experiences of developed countries, proposals including completing the system of laws and regulations, enhancing operability, strengthening surveillance and law enforcement, and improving supporting legal systems were put forward in the end of this study.Keywords：crop straw;burning control;comprehensive utilization;laws and regulations7|9|6<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
