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【Objective】 Wheat is the most important crop in North China. However, the scarcity of freshwater resources in this region cannot sustain its production. Optimizing wheat planting area to balance wheat production and its water requirement is hence essential to conserving irrigation water and alleviating water shortage pressure. 【Method】 Evapotranspiration and wheat yield were used as indicators to establish the objective of the wheat planting areas at county scale in the region. Optimization for wheat production was established from the trade-off between wheat production and its water consumption. 【Result】 From 2001 to 2009, evapotranspiration in the wheat season exhibited an increasing trend, followed by a significant decrease from 2010 to 2018 (p

Intercropping creates a heterogeneous canopy and triggers plastic responses in plant growth and structural development. In order to quantify the effect of planting pattern, strip width and row position on the structural development and light capture of maize and soybean in simultaneous intercropping, both experimental and modelling approaches were used. Field experiments were conducted in 2017－2018 with two sole crops (maize and soybean) and two intercrops: Two rows of maize alternating with two rows of soybeans (2:2 MS) and three rows of maize alternating with six rows of soybean (3:6 MS). The morphological traits of maize and soybean e.g., leaf length and width, internode length and diameter, leaf and petiole declination angle in different rows and different planting patterns, and photosynthetically active radiation (PAR) above and below the canopy of 2:2 MS were measured throughout the growing season. A functional-structural plant model of maize-soybean intercropping was developed in the GroIMP platform. The model was parameterized based on the morphological data set of 2017, and was validated with the leaf area index (LAI), plant height and PAR data set of 2018. The model simulated the morphological development of individual organs based on growing degree days (thermal time) and calculated the light capture at leaf level. The model well reproduced the observed dynamics of leaf area index and plant height (RMSE: 0.24－0.70 m2/m2 for LAI and 0.06－0.17 m for plant height), and the fraction of light capture in the 2:2 MS intercropping (RMSE: 0.06－0.10). Maize internode diameter in intercrops increased, but the internode length did not change. Soybean internodes in intercrops became longer and thinner compared to sole soybean probably caused by the shading imposed by maize, and the 2:2 MS had longer internodes than the 3:6 MS, indicating the effects of strip width. Simulated light capture of maize in 2:2 MS intercropping was 35.6% higher than sole maize. For maize in 3:6 MS intercropping, the light capture of the border rows and inner row were 27.8% and 20.3% higher than sole maize, respectively. Compared to sole soybean, the simulated light capture of soybean in border rows was 36.0% lower in 2:2 MS intercropping, and was 28.8% lower in 3:6 MS intercropping. For 3:6 MS intercropping, light capture of soybean in inner rows I and inner rows II were 4.1% and 1.8% lower than sole soybean, respectively. In the future, the model could be further developed and used to explore and optimize the planting patterns of maize soybean intercropping under different environmental conditions using light capture as an indicator.

To determine the correlation between dominant microorganisms and physicochemical characteristics of pickle brine. Analysis of the correlation between physicochemical properties and microbial communities was revealed, while the microbial community structure was investigated using high-throughput sequencing technology. The results showed that: The total acid content of pickle brine was 3.00-18.90 g/kg, the pH value was 3.27-4.71, the salt content was 11.00¬15.50 g/100g, and 7 kinds of organic acids including oxalic acid, malic acid, succinic acid and lactic acid were de¬tected. The dominant microbial phylums include Firmicutes and Ascomycota, accounting for more than 99.00% of the to¬tal. The dominant bacterial genera were Lactobacillus and Pediococcus. The dominant fungal were Pichia, Kazachstania and Debaryomyces. The correlation analysis showed that Lactobacillus had a significant positive correlation with lactic acid (P<0.05) and acetic acid (P<0.01), and Pediococcus had a significant positive correlation with malic acid (P<0.01). In summary, Lactobacillus spp. and Pediococcus were the dominant microorganisms in the pickle brine. This provided a reference for the selection and breeding of efficient fermentation strains of pickle brine and industrialization of pickles. [ABSTRACT FROM AUTHOR]

Food security is an important guarantee of national security. The northeast black soil region is an important commodity grain production base in China, which plays a fundamental role in ensuring national food security. However, the highly intensive, unreasonable or excessive use of cultivated land in this region has caused serious black soil degradation. Therefore, how to make the Black Soil Granary to provide efficient and sustainable guarantee for national food security is a scientific problem requiring urgent solutions. This paper systematically illuminates the agricultural development of high-productivity black soils since the reform and opening-up. On this basis, the paper systematically summarizes the problems facing the sustainable development of grain production in the black soil region. Furthermore, to meet the requirements of the central government for agricultural production in Northeast China, it puts forward the corresponding countermeasures to coordinate food security and ecological security and to enhance the sustainable development of grain production, intending to provide reference for the sustainable agricultural development in the northeast black soil region, and offer scientific guidance for the strategic planning of national food industry strategy, agricultural policy making, and strengthening of national food security. [ABSTRACT FROM AUTHOR]

Plant architecture is an important determinant of the canopy light interception and photosynthesis. Therefore, effective and nondestructive methods for obtaining plant architecture can help us understand the relationships between plant physiological processes and morphogenesis. Digital camera technology has become relatively ubiquitous and inexpensive, leading to a recent surge in utilizing plant imaging to capture data. Therefore, a three-dimensional (3-D) reconstruction of plant architecture based on these photographed image sequences can be realized. However, the accuracy evaluation of reconstruction is always determined from visual effect and or from 1-D or 2-D measured data. In this study, image sequences were obtained around experimental plants (e.g. egg plant, sweet pepper and cucumber) by slightly moving a commercial camera for image generation so that each neighboring image pair shared short baseline. Structure from motion (SFM) method was applied to produce a set of sparse point cloud based on plant image sequences. As the sparse point cloud was inadequate for the reconstruction of complicated plant architecture, multiple-view stereo (MVS) method was further used to produce dense and accurate point cloud based on the output of SFM. Software Bundler and CMVS were applied to implement the SFM and MVS methods, respectively. Bundler takes a set of images as input, and produces a 3D reconstruction of sparse scene geometry and camera parameters as output. CMVS takes a set of images and camera parameters (the output of Bundler) as input, and outputs a set of dense points with geometry details. Once original point cloud has been obtained, point cloud processing procedures were conducted to refine point cloud, including deleting noise points and scaling to the actual size of experimental plants. In order to obtain point cloud of individual blade, segmentation of point cloud of plants was conducted based on region growing segmentation algorithm. Once point cloud of individual blade was obtained, Poisson surface reconstruction algorithm was used to reconstruct each leaf. Before accuracy evaluation, point cloud of individual leaf blade and corresponding laser scanning point cloud were aligned to the same 3-D coordinate system using the Iterative Closest Point algorithm. Then, comparison on 3-D scale based on Hausdorff distance was made between point cloud data obtained from plant image sequences and referenced point cloud data with laser scanning on individual leaf blade level. Furthermore, phenotypic attributes, such as leaf blade width, leaf blade length and blade area were extracted based on data from image sequences and from laser scanning methods. Besides, these attributes of each blade were manually measured. Finally, comparisons were made for blade area, blade length and blade maximum width between data from the image sequence-based model, laser scanning based model and manually measured data. The results showed that high accuracy of 3-D reconstruction was obtained based on plant image sequence method. Hausdorff distances of experimental plants were ranged from 0 to 10 mm, and most of the values were less than 4.0 mm. There was a good agreement between measured and calculated blade area, blade length and maximum width with R² > 0.95 for blade area, RMSE < 4.5 mm for blade width, and RMSE < 5.6 mm for blade length. There was no significant difference for each attribute between measured and calculated data (ANOVA, P > 0.05). A key advance of the current 3-D reconstruction of plant architecture is the capability to non-destructively capture plant traits with high accuracy. This advance permits time-series measurements that are necessary to follow the progression of growth and stress on individual plants, and will play an important role in related research fields, such as plant phenotyping, genetic breeding, interactions between plant phenotype and environment. [ABSTRACT FROM AUTHOR]

There is an important significance for China's food security to explore the fluctuation characteristics and influence factors of grain output per sown area (hereinafter referred to as grain yield), and then to take corresponding measures to stabilize and improve the grain yield level. In this paper, the time-series yields of grain and main crops (rice, wheat and maize) from 1978 to 2012 in China were decomposed using empirical mode decomposition (EMD) method, and then multi-scale fluctuation characteristics and its main influence factors of grain yield were analyzed. The results showed: 1) the time series of grain yield could be decomposed into two intrinsic mode functions (IMF) and a residual item. The residual item denotes a slow and steady rising trend in grain yield which is dominated by the technological progress. The IMF1 and IMF2 represent a short-term fluctuation in about 4-yr cycle and a medium-term fluctuation in about 9-yr cycle, which respectively reflect the influence of meteorological and policy factors on grain yields according to the analysis of grain production system. The variance contribution rate of the residual item was greatly larger than that of the IMFs, which means the upward trend in grain yield was more pronounced than fluctuations. 2) Fluctuation of trend yield of grain was distinct before and after 1997: fast rise with an average annual growth rate of 2.28% before 1997 and slow rise with an average annual growth rate of only 0.69% after 1997. The change of trend yield was similar between rice and grain, but the former seemed to rise more slowly after 1997. For wheat and maize, the trend yield was still increased obviously although the growing rate had been significantly slowing down after 1997. 3) The IMF2 included 3 complete cycles (1979-1988, 1989-1993, and 1994-2002) and an ongoing cycle (2003 to present) which coincided with adjustment of Chinese agricultural policy. In general, the impact of policy and market factors on fluctuation of grain yield is greater than that of climate factors, but responses of different crops to different policies varied: policies on land, tax, subsidies, incentives and insurance had positive or negative effect on medium-term fluctuation of main crops synchronously, but price policies was not the case for main crops especially for maize. Medium-term fluctuation rate of grain yield was 2.94%, and that of wheat was 3.83%, significantly higher than that of maize (2.38%) and rice (2.18%). It suggested wheat's vulnerability to policies. 4) The short-term fluctuation rate of grain yield was 1.80%, and that of maize, wheat, and rice was 3.38%, 2.55%, and 1.06%, respectively. It indicated that Chinese grain production system had a strong ability to resist against meteorological disaster. The disaster prevention capabilities of different crops was not the same, and maize was more easily affected by meteorological disasters than wheat and rice. 5) Both considering the short-term and medium-term fluctuation rates, rice was the most stable crop in yield. The main problem of rice production was the slow growth of yield trend after 1998, while maize was strongly influenced by meteorological disaster, and fluctuation of wheat was significantly affected by policy cycles. At present, China's agriculture production has entered a new development stage. It is necessary to adjust the agricultural policy in order to adapt to the new situation. The results here can help with decision-making and adjustment of agricultural policies. [ABSTRACT FROM AUTHOR]

The quantitative description of soil water flow, carbon (C) and nitrogen (N) cycles, and crop growth processes at soil-plant-atmosphere continuum system is important for improving water and N use efficiencies and decision-making of crop production and environmental protection in the North China Plain (NCP). The objective of this study was to develop a water and N management model for intensive cropping systems and agricultural management practices in NCP. Based on the previous research findings, a coupled model (Soil Water Heat Carbon and Nitrogen Simulation, WHCNS) model was established. The model included 5 main modules: soil water, soil heat, soil C, soil N, and crop growth. The Penman-Montheith method from the Food and Agriculture Organization of the United Nation was used to calculate the reference crop evapotranspiration. The method for simulating soil water movement and heat transfer was directly introduced from the HYDRUS1D and RZWQM models. The PS123 model from the Netherlands was used to simulate crop growth. The simulation of C and N cycles was done by the Daisy model from Denmark. The model ran on a daily time step and was driven by the meteorological and crop biological variables, and agricultural management practices. The soil water infiltration and redistribution processes were described by Green-Ampt and Richard's equations, respectively. Soil N transport simulation was based on the modified convection-dispersion equation. The source-sink term of N transformation and transport included mineralization of soil organic N, immobilization in biomass, urea hydrolysis, ammonia volatilization, nitrification, denitrification, and crop uptake. The compensatory absorption mechanism was introduced in crop water and N uptake. The organic matter pools were divided into 3 active and 3 stabile C pools. The improved version of the PS123 model was applied to simulate crop development stage, dry matter production and allocation, and crop yield. The crop yield under water and N stress was calculated based on the simulation of potential and actual crop water and N uptake. Then the field applicability of the WHCNS model was tested using the two-year field observed data of winter wheat and summer maize system at Tai'an experimental site in Shandong province. The statistical indices (root mean square error, modeling efficiency, and agreement index) all indicated that the simulated values of crop yield, leaf area index, soil water content, and nitrate concentration in the soil profile all agreed reasonably well with the observed values, especially for crop yields with the root mean square error ranges from 205.5 to 318.8 kg/hm2, the correlation coefficient of 0.90, and modeling efficiency values larger than 0.75 and concordance index larger than 0.9. We concluded that the WHCNS model could be used to simulate water movement and the fate of N as well as crop growth in high intensive cropping system in North China. [ABSTRACT FROM AUTHOR]

Soil salinization can directly affect crop production, and threaten the sustainable utilization of irrigated land. This problem is particularly prominent in Xinjiang Uyghur Autonomous Region, where has much uncultivated arable land, and soil saline and secondary salinization after land development. In this study, field experiments were conducted to investigate the influence factors and characteristics of soil salt movement, as well as elution desalination in different improvement measures treatments of severe saline soil through 3-year experiment. Five improvement treatments were designed including agricultural improvement (mainly including mulched with plastic film, deep plowing, returning straw and organic fertilizer), salt-isolation to root zone plus agricultural improvement, subsurface pipe drainage plus agricultural improvement, chemical modified plus agricultural improvement, and control without any human activity on new reclamation farmland in Xinjiang Province. The results indicated that salt content of the soil was mainly affected by evaporation, irrigation amount and groundwater depth; the soil salt content was significantly negative correlated with irrigation amount (correlation coefficient=-0.871, P=0.0039) and groundwater depth (correlation coefficient=-0.831, P=0.0072), positively correlated with monthly evaporation (correlation coefficient=0.754, P=0.0084), but not significantly correlated with mean monthly temperatures; The effect of irrigation amount on the 0-80 cm soil salinity in entire growth period was the most prominent. In the 3-years, dynamic changes in soil saline content varied with different improvement methods: high salt content accumulated in the top and deep layers of soil throughout the growing period for agricultural improvement treatment; obvious salt accumulation in the top layer of soils for salt-isolation to root zone plus agricultural improvement; the salt content at the deep layer higher than in subsurface layer for pipe drainage plus agricultural improvement, and chemical modified plus agricultural improvement treatment. The desalination rate of soils after the first-year was not satisfactory, and that after the second-year was significantly improved. The desalination rate of soil in the treatment of salt-isolation to root zone plus agricultural improvement and subsurface pipe drainage plus agricultural improvement treatment was up to 44% in the second year, but was significantly decreased in the third-year due to the reduction of the total salt content of the soil. Overall, all the treatments could result in the decrease of soil salt content. Among them, the soil desalinization rates of agricultural improvement plus subsurface pipe drainage and salt-isolation to root zone plus agricultural improvement were 61.33% and 59.37% respectively in the 0 to 80 cm layers, which were better than the other treatment. The soil desalinization rate of chemical modified plus agricultural improvement treatment was 55.32% in the 0 to 40 cm layers, higher than agricultural improvement 45.42%. The results can provide valuble information for saline soil improvement and rational development and effective utilization of saline soils in the Xinjiang arid zone. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and safety of the regimen of low-dose high intensity focused ultra-sound (HIFU) plus S-1 and oxaliplatin (SOX) in the treatment of metastatic colorectal cancer patients with pelvic masses., Methods: A total of 46 patients with metastatic colorectal cancer were recruited and divided into 2 groups: Twenty patients received concurrent HIFU plus S-1 and oxaliplatin (SOX) while another 26 patients SOX alone. The baseline characteristics, progressive-free survival, overall survival time and adverse events were retrospectively analyzed., Results: The median PFS was 11.2 months (95% CI 9.8-12.7) in the HIFU+SOX group and 7.1 months (95% CI 5.8-8.4) in the SOX group (P = 0.003). And the overall survival time in two groups were 21.9 months (95% CI 18.0-25.9) and 16.9 months (95%CI 14.1-19.6) (P = 0.072) respectively. Major toxic effects included grade 3/4 neutropenia (15%), anemia (10%), thrombocytopenia (10%), diarrhea (15%) and hand-foot syndrome (10%) in the HIFU+SOX group. And it showed no statistically significant differences with the SOX group., Conclusion: The combined regimen of HIFU and SOX is effective and well-tolerated in patients of late-stage colorectal cancer with pelvic masses.

In this study, a controlled experiment of winter wheat under water stress at the seedling stage was conducted in soil columns in greenhouse. Based on the data gotten from the experiment, a model to estimate root length density distribution was developed through optimizing the weights of neural network by genetic algorithm. The neural network model was constructed by using forward neural network framework, by applying the strategy of the roulette wheel selection and reserving the most optimizing series of weights, which were composed by real codes. This model was applied to predict the root length density distribution of winter wheat, and the predicted root length density had good agreement with experiment data. The way could save a lot of manpower and material resources for determining the root length density distribution of winter wheat.

Winter wheat straw particles (0.5 ~ 2.0mm) were soaked with 8.0 g.L-1 H202(pH11.0), 12.5 g.L-1 Na0H or H2S04 solution for 8 h and dried at 80 degreeC. Soils amended with the pretreated straw and inorganic N were incubated aerobically at 25 degreeC for 60 days. The C02 emission rate and soil microbial biomass C and N were measured at different time. The results showed that during the earlier stage of incubation, the pretreatments of straw increased soil microbial biomass C by 1.0 ~ 1.4 folds, but decreased soil microbial respiration activity. During the later stage of incubation, the Na0H and H2S04 pretreated straw decreased soil microbial biomass carbon by 28% and 42%, respectively, while increased the soil microbial respiration activity. The straw pretreated by H202 increased soil microbial biomass nitrogen by 90% after the 15th day of incubation. The pretreatments of straw increased the fungi/bacteria ratio at different special time. It could be concluded that soil microbial biomass and respiration activity could be changed after the pretreated straw was added into the soil.

Most studies on bacterial transport in soils were carried out in columns under controlled conditions, and the results were various, reflecting the need of standardizing the method. Other methods were also used in conjunction with microscopy to examine the transport at pore scale. Mathematical models based on convection-dispersion equation were developed to simulate bacterial transport. Within specific limits, these models could simulate the major behaviors of bacterial transport. However, they neglected some parameters such as the growth and death of bacteria. The theoretical development, experimental size, scale exchange and modeling for predicting bacterial transport at field scale should be further studied.

Objective: To study the relation between different cultivated varieties and quality of Radix Glehniae., Methods: Polysaccharide, imperatorin and extractives in different varieties were detected according to document and Chinese Pharmacopeia., Results: Each content of soluble carbohydrate, rough polysaccharide, total carbohydrate, water extractives and alcohol extractives in Baitiao is significantly higher than that in other two varieties (P < 0. 05). The content of imperatorin is highest in Dahongpao P < 0.05)., Conclusion: It is more effective for Baitiao to restrain humor immunity,cell immunity and the overgrowth of T and B cells. Dahongpao is dominani as sedative, spasmolytic and abti-asthmatic.

Four insoluble phosphates of ferric phosphate (Fe-P), aluminum phosphate (Al-P), fluorapatite (FAP) and rock phosphate (RP) were used as a sole phosphorus resource for some phosphate-solubilizing microorganisms. It was found that there was significant difference in solubilizing these phosphates by the tested isolates. The fungi normally were more powerful than the bacteria in dissolving the phsophates. The microorganisms generally solubilized more phosphate when supplied with NO3- than with NH4+. However, the isolates of 2TCiF2 and 4TCiF6 had much higher capacity to solubilize FAP and Al-P respectively in NH4+ medium. Most of the isolates solubilized readily FAP and RP, and then Al-P. Ferric phosphate was the least soluble to these isolates. Only isolate 2TCiF2 showed strong ability to solubilize Fe-P. In particular, two Aspergillus sp. had much higher capacity of dissolving Fe-P when suppled with NO3-. The isolates of Evwinia sp. 4TCRi22 and Enterobacter sp. 1TCRi15 had higher capacity of solubilizing FAP. But two Arthrobacter sp. showed the highest activity in RP medium. It is supposed that complexion of organic acids with metals may be the main reason for these isolates to solubilize the phosphates. However, other chelant substances may be much more important for Enterobacter sp. and Erwinia sp. to release phosphorus from the phsphates.