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- Abstract：Energy plant cultivation has been recognized to be essential for biomass energy production,which will enhance greenhouse gas emission reduction and low carbon economy.In this article we overviewed the energy plant concepts and clarified energy plant classification based on the plant system,photosynthesis pathway,life cycle,and chemical composition and utilization.Energy plants are classified into sugar plant,starch plant,oil plant,oil microalgae,and lignocellulosic plant based on their chemical composition and utilization.Afterwards,the latest technologies of conversion from biomass to energy and related bioenergy products were overviewed.Liquid biofuels include bio-ethanol,bio-diesel,and pyrolysis oil and gaseous bio-fuels include synthesis gas,biogas,and hydrogen.From lignocellulosic biomass feedstocks pellet and briquette are produced with compaction technologies and electricity and heat are conversed with the combined heat and power generation technologies.Keywords：crop;energy plant;biomass;energy transform6|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The research selected A3-type and A1-type cytoplasmic sweet sorghum hybrids as material,to study their difference of biomass,brix,juice extraction and expected sugar yield using bagged and non-bagged treatments.The results showed that biomass,brix and total sugar yield of sterile A3 cytoplasmic hybrid increased significantly,although its juice extraction was decreased.So A3-type cytoplasmic sorghum hybrids can completely be used on bioenergy sweet sorghum production.It would provide a new approach to resolve the problems of A1-type cytoplasmic sweet sorghum hybrids,such as lodging,harvesting in different time and bird damage.Keywords：sweet sorghum;A;3;-type cytoplasm;biomass;brix3|10|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Low temperature in winter is an adverse abiotic stress to sugarcane industry,and caused significant loss.In order to investigate the response of Ca2+ and Ca2+-ATPase activity in the stem tip of different cold sensitivity sugarcane cultivars,Electron microscope (EMS) and phytohistochemistry technology were employed to detect the changes of Ca2+ level and Ca2+-ATPase activity in the stem tips of two sugarcane varieties YL6 (cold sensitive) and GT28 (cold resistant) before and after low temperature treatment.The plants were treated at 0 ℃ in fridge and samples were taken after treatment at 0,2,4 and 6 d,respectively.The results showed that there was no significant morphological difference and cellular structures in the stem tip of GT28 before and after low temperature stress.On the contrary,the cells in the stem tip of YL6 showed plasmolysis with mitochondria vacuolization,the cells were distorted and broken down,and the tissues were fully hygrophanous with the ongoing of the stress.Both sugarcane cultivars showed accumulation of Ca2+ pellets in cytoplasm and nucleolus of the stem tip cells at the beginning of low temperature stress.The accumulated Ca2+ pellets in GT28 decreased and maintained at low level with the ongoing of the stress,but those in YL6 maintained at high level.Low temperature stress showed very little influence on the Ca2+-ATPase activity and its distribution in GT28,which kept high-level.On the contrary,Ca2+-ATPase activity in YL6 reduced with the ongoing of stress.In conclusion,high level of Ca2+ in cytoplasm is one of the important reasons that responsible for cell injury,while high Ca2+-ATPase activity might play an important role in avoiding high Ca2+ toxicity.Keywords：sugarcane;stem tip;low temperature;Ca;2+;-ATPase1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Mitochondria is an important organelle in eukaryotic cell,which offer energy,the necessity of cell life.Mitochondria have a semi-autonomous genetic system encoding part of its functional genes,which involved in a number of processes of life activities.In recent years,many progresses have been achieved in sequencing the mitochondrial genomes of higher plants.And it was found that plant mitochondrial genomes are more complicated than those of animals.And plant mitochondrial genomes have closely relationships with the cytoplasmic male sterility (CMS) and the evolution of species.So understanding the mitochondrial genome and getting more information are helpful to study the mechanism of CMS and evolution of species.In this paper,we summarized the research progress on the mitochondrial genome sequencing,and the relative alignment analysis on plant mitochondrial genomes of the size,composition,gene composition and expression,RNA editing,sequence recombination,and the research progress of the genome structure and genome evolution and male sterility mechanism.Keywords：plant;mitochondria;genome;DNA sequence4|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The effects of straw returned to the field which including no straw returning (CK),wheat straw returning (T1),maize straw returning (T2) and wheat and maize straw returning (T3) on emergence,growth,yield and water use efficiency of maize under field location condition to generalize the techniques of total straw of wheat and maize returned to the filed in lime concretion black soil region of Huaibei plain.The results showed that to compared with CK,the maize emergence number of T3 were increased by 3.25% and 11.98% in 2008 and 2009,respectively.The emergence rate, emergence uniformity,evenness of plant height,seedling quality and soil water content of T3 were higher than that of CK,which created a good population growth condition for maize,thus the population leaf area index and dry matter accumulation of that were improved.Finally,be compared with CK,the yield of T3 were increased by 7.92% and 9.51% while water use efficiency of that were increased by 8.15% and 9.48% in 2008 and 2009,respectively.Therefore,under the condition of wheat/maize straw returned in two seasons,the growth and grain yield of maize could be improved.Keywords：lime concretion black soil;straw returned to the field;maize;emergence;water use efficiency9|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The emergency of genomic sequences in tomato (Solanum lycopersicum L.) provides a base for developing InDel markers.In this study,18 InDel and 22 SSR markers were used to analyze genomic DNA diversity in 59 Chinese and 23 US fresh-market tomato varieties to investigate the potential use of InDel markers in tomato molecular breeding.Comparison between 59 Chinese and 23 US varieties were also conducted at marker level.The results indicated that InDel marker showed lower polymorphisms than SSR markers in 82 varieties.The number of alleles amplified by InDel primers was significantly lower than that amplified by SSR markers in Chinese varieties.But no obvious difference was observed in US varieties.The number of alleles amplified by InDel primers was significantly lower in Chinese varieties than in US varieties.Cluster analysis indicated that genetic difference was very low among varieties developed by Chinese breeding programs but relatively high between Chinese and foreign varieties.Keywords：Solanum lycopersicum;InDel;SSR;marker polymorphism;genomic DNA diversity4|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Seed priming is one of advanced seed treatment technologies in international.In this study,water priming on seed germination and vigor of four different size grades of spinach seeds were conducted with vigor indexes characterized by seedling growth test,conductivity test and simulated field test.The results showed that it was detrimental to seedlings’s health after pericarp removal and vigor of spinach (Spinacia oleracea) seeds of different size grades were obviously improved by water priming.And different size grades of spinach (Spinacia oleracea) seeds had the different optimum time of soaking and keeping humidity.The result was that seed diameter(d for short) <1.7 mm was 10 min,24 h;1.7 mm≤d<2.5 mm and 2.5 mm≤d<3.0 mm were 20 min,24 h;d≥3.0 mm was 30 min,24 h.Keywords：spinach;seed germination;seed vigour;water priming;temperature4|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to understand the relationship between the changes of membrane fatty acid of Spiraea and its cold resistance,the garden trees Spiraea fritschiana Schneid.and Spiraea bumalda 'Goldmound’ with different cold resistance were used as materials,applying gas chromatography technology,designing low-temperature and deacclimation treatment,studying the species and the contents changes of their membrane fatty acid under low-temperature treatment.The results showed that the membrane fatty acid in S.fritschiana Schneid.and S.bumalda'Goldmound’ were mainly composed of myristic acid (14∶0),palmitic acid (16∶0),oleic acid (18∶1),linoleic acid (18∶2) and linolenic acid (18∶3).They composed more than 90% of total membrane fatty acid,saturated fatty acid was mainly composed by palmitic acid (16∶0),unsaturated fatty acid was mainly composed by linoleic acid (18∶2) and linolenic acid (18∶3).The unsaturated membranes fatty acid contents in S.bumalda 'Goldmound’ changed significantly under low temperature treatment,the unsaturated membrane fatty acid contents in S.fritschiana Schneid.changed non-significantly while the same treatment,its stronger cold-resistance might be related to the IUFA level that was more stable under low temperatures.A certain low-temperature level was needed in order to maintain a more stable unsaturation membrane fatty acid level to S.fritschiana Schneid.There was a certain influence to the saturated membrane fatty acid contents in S.fritschiana Schneid.and S.bumalda 'Goldmound’ under low temperature treatment.4|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Gibberellins (GA) are key plant hormone which promotes the enlargement of seedless grape berries.GA receptor and the pathway of GA signal transduction in grape berries are still unknown.Basing on sequence comparison of already isolated GA receptors from other plants,7 putative GA receptor GID1 genes were identified from the grape genome.They were analyzed with BLAST program,and specific primers were designed accordingly.Semi-quantitative RT-PCR showed that these 7 genes are of different transcription levels in mature leaves,young leaves,inflorescences,shoots and dormant buds.Bunches of Centennial seedless were treated with 30 mg/L GA3 on 12 days after flowering (DAF).Berried were collected at the first rapid growth stage (19 DAF),slow growth stage (45 DAF) and the second rapid growth stage (61 DAF).Semi-quantitative RT-PCR demonstrated that these putative GID1 genes,except VvGID1-4 and VvGID1-5,were down-regulated or up-regulated by GA treatment.Our results lay the foundation for future work on full sequence clone and functional study of grape GA receptors.4|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：This study is to analysis the changes of components content of dietary fiber in peach pomace during fermentation.Peach pomace was stored in a sterile container,compressed oxygen and made the condition as much as anaerobic fermentation that happens without oxygen.In addition,other peach pomace was stored in a sterile container too,stirred constantly to increase the gap and made the condition as much as aerobic fermentation that happens in oxygen.The result shows that,in aerobic fermentation,the contents of total dietary fiber,cellulose,soluble pectin are deceased by 14.9%,17.1%,14.4%;the content of soluble dietary fiber is increased by 7.7%;the content of total pectin dont change significantly.In anaerobic fermentation,the contents of total dietary fiber,cellulose and soluble pectin are deceased by 20.4%,10.4%,9.86%;the content of soluble dietary fiber is increased by 13.7%;the content of total pectin is decreased by 1.03%.Therefore,dealing with fresh peach without delay can benefit to maximum extraction rate of components of dietary fiber in peach pomace.Keywords：peach pomace;accumulation;dietary fiber;pectin;cellulose3|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：For studying the low seeded rate of apple-pear hybridization,we hybridized apple with pear:Malus domestica cv. Red Fuji Spur×Pyrus pyrifolia cv. Gold Nijuseiki;Pyrus pyrifolia cv. Gold Nijuseiki×Malus domestica cv. Gala.Pollen germination,pollen tube growth in style and type of seed were investigated,respectively.Growth inhibition of pollen tubes in distant style is a reason for low seeded rate,while abnormal growth of hybrid seeds is another reason.The growth inhibition of Gold Nijuseiki pollen tube in Fuji style,which happens in the foreside of Fuji style,is stronger than that of Gala pollen tube in Gold Nijuseiki style in which inhibition occurres in the middle of style.This inhibition may be caused by the different structure of apple and pear styles.In Fuji×Gold Nijuseiki,the seeds growth inhibition is seed abortion,while in Gold Nijuseiki×Gala this inhibition leads to thinness seeds and abnormal seeds.1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to achieve the precise control of potted Begonia × elatior production,how begonia absorbed and utilized water and nutrition at its different developmental stages were studied by equation regression.It was found that,the change curves of begonia’s uptake of water and nutrition matched S pattern,as well as the change curves of the accumulation of drymass.The determination coefficient of the logistic model was higher than 0.99.The change curves of begonia’s drymass accumulation rate,water use efficiency and nutrition absorption rate were right deviation bell-shaped along the culturing time.According to these results,the optimized proposal was developed based on begonia’s average utilization rate of water and nutrition at different developmental stages.This will provide the necessary technical support of lowing begonia’s cost,optimizing its quality and producing with higher efficiency under certain water and nutrition control.Keywords：Begonia × elatior;water;nutrition;absorption and utilization;precise control0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In present study,the effects of temperature,light and acidity on the expression of Omega-3 fatty acid desaturase of 3 species of marine microalgae including Phaeodactylum tricornutum,Chlorella vulgaris and Isochrysis galbana were detected.The results revealed that the expression of Omega-3 fatty acid desaturase of 3 species was down-regulated following treatment with lower temperature at 10 or 15 ℃,while the transcripts of the gene were up-regulated after treatment at 25 or 30 ℃ (Phaeodactylum tricornutum was excluded).An increased expression of Omega-3 fatty acid desaturase was also found when 3 species of marine microalgae were treated with light at intensity of 5 000 lx for 48 or 72 h.The results also demonstrated that the acidity produced effects on the expression of Omega-3 fatty acid desaturase of the microalgaes in association with the species.Results of culturing in pH 5－9 showed that the acidity had a greater effects on Phaeodactylum tricornutum,whereas a moderate effects on Isochrysis galbana and a smaller effects on Chlorella vulgaris.Keywords：microalgae;Omega-3 fatty acid;desaturase;gene expression1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：It aimed to utilize bagasse and fasten its conversion into feed through bagasse fermentation.Sucrose was used to adjust the initial water-soluble carbohydrate content (WSC) to 2%, 3%, 4%, 5%, 6%, and 7% (w).And a lactic acid bacteria community LBC-8 was inoculated into the bagasse as the inoculation group.The treatments with only the sterile MRS broth were used as the control group.During the fermentation,bio-chemical parameters and microbial diversities were analyzed.The result showed that after 20 d fermentation,the pH values of the inoculation group were lower than that of the control group,and the trends of pH falling were related to the initial WSC content,the lowermost pH value of the inoculation group was 3.3.There were significant lactic acid produced and better appearance quality when initial WSC content was above 5% in the inoculated group.The WSC,crude protein,crude fiber,crude ash contents were 1.93%,2.26%,41.1% and 4.43% separately when the WSC content was 5% after 20 d fermentation.From the patterns of denaturing gradient gel electrophoresis (DGGE),after inoculation,the bacteria of LBC-8 rapidly became the advantageous species in the inoculated group when initial WSC content was above 5%.In the contrast,the advantageous bands were less in the control group.Comprehensive results showed that the bagasse fermented feed with good fermentation quality was obtained when the lactic acid bacteria community LBC-8 was inoculated into the bagasse with initial WSC content of above 5%.Keywords：bagasse;lactic acid bacteria;fermentation quality;DGGE0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The present study aims to measure DHEA physiological changes,and check whether dietary DHEA supplementation can affect serum DHEA and lipid metabolism in barrows.In studyⅠ and Ⅱ,the blood samples of boars,gilts and barrows (28-203 day-old) were taken for analyzing serum DHEA and DHEA-S.In study Ⅲ,45 crossbred Duroc×Landrace×Yorkshire barrows weighing approximately 40 kg at the start of the trail (98 day-old) were allocated randomly into 3 groups with 15 barrows in each group.The barrows were fed with the diet supplemented with 0,25 and 75 mg/kg DHEA.The pigs were slaughtered after the 105-day trail.The results showed that serum DHEA levels in boars were significantly higher than which of the gilts.After boars were castrated, the serum DHEA concentration was significantly lower (P<0.001),and showed a U-shaped pattern.Dietary DHEA significantly increased serum DHEA concentrations,but reduced serum cholesterol and triglyceride levels,while the concentration of serum DHEA-S had no significant effect.Backfat thickness and the index of the perirenal,mesenteric were reduced,whereas the body weight was unaffected.The physiological changes of DHEA and effects of DHEA treatment on lipid indices,suggest that the steroid may be involved in the modulation of lipid metabolism in barrows.Keywords：barrows;dehydroepiandrosterone (DHEA);physiological levels;lipid metabolism;lipid deposition1|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this research is to explore siRNA expression plasmid vector on gene VEGF,and the expression of this plasmid in granular cells of ovine ovary.The granular cells of ovine ovary were cultured in vitro using DMEM/F12 (containing 10% FBS),and the four kinds of vectors constructed before were transfected into granular cells using lipofectamine 2000.The control group is granular cells transfected vector PGC,and the other three groups are granular cells transfected vectors PGC-1,PGC-2,PGC-3 respectively,named Group Ⅰ、Group Ⅱ and Group Ⅲ.The expression of VEGF in fibroblast was calculated by standard curve which was drawn according to ELISA.Compared with the control,the expression of VEGF in treatment groups were partly lower 55.37%,81.45% and 73.29%.The interference efficiency of PGC-2 is the best of all.Keywords：sheep;VEGF;granular cell;transfection2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To study the regulatory mechanism on apoptosis in sheep generative organ at follicular phase,in situ fluorescent labeling (4',6'-diamidino-2-phenylindole,DAPI) was used to confirm and locate apoptosis cells in major reproductive organs (ovaries,oviduct and uterus) of Small-tails Han Sheep (SHS) and Suffolk Sheep (SS),which have high and low productivity respectively.The finding of in situ fluorescent labeling (DAPI) indicate that,apoptosis might take place in follicular epithelium cells (FeC),granule cells (GrC) and theca cells (ThC) of SHS and SS.Suffolk Sheep had more apoptosis of GrC and ThC in tertiary follicle and graafian follicle (VG) than SHS.Neither SHS nor SS apoptotic cells were detected in oviduct and glandular organ during follicular phase (FP).While a few endometrial stroma cells (StC) with apoptosis were detected.The result showed that apoptosis is an important regulatory mechanism in reproductive organs of ewe,and it might result in difference in production between SHS and SS.Keywords：sheep;follicular phase;DAPI;apoptosis2|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the associations between serum biochemical indices and their changing at early period of heat stress with heat tolerance,sixty four day-old female chickens produced by hybridization of Anak 40 (♂) and Linnan Yellow (♀) were treated under a (38±1)℃ heat stress, and the associations between initial levels as well as the changing in 12-h heat stress of 5 biochemical indices and survival time during heat stress were analyzed.Results showed that the initial serum GLU level ((12.33±0.88) mmol/L) of Group (chickens that survive from the heat stress or over 36 h) was higher (P<0.05) than Group (chickens that survive no more than 24 h),and the initial GLU level is significantly correlated to survival time (r=0.48,P<0.05).The changing of serum GLU and GLB level of Group in the early 12 h of heat stress were 35.6% and 5.0%,respectively,which were higher (P<0.05) than which of Group Ⅱ.The correlation coefficients between the changing of serum GLU,GLB as well as ALB level in the early 12 h and survival time were －0.82(P<0.01),－0.53(P<0.01) and －0.45(P<0.05),respectively.Therefore, the changing of serum biochemical indices during the initial stage of heat stress closely associated the heat tolerance,and it can be used in the evaluation of heat tolerance in chicken.Keywords：chicken;heat stress;biochemical index;evaluation1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：This study focuses on construction and identification of immunized phage display library from splenocytes of hyperimmunized BALB/C mice for screening and isolation of scFv fragment against ENR,an alternative method to produce antibodies for veterinary drug residues detection.The total RNA was isolated from splenocytes of a BALB/C mouse hyperimmunized with the Enrofloxacin conjugated to chicken OVA.Variable light and heavy domains of the immunoglobulin genes were amplified by PCR and assembled to produce full-length single-chain Fv(scFV) by overlap extension PCR using a linker primer containing flexible polypeptide-(Gly3Ser)4.The scFv DNA fragment was ligated into phagemid vector pCANTAB5E and electroporated into E.coli XL1-Blue cells.The transformed cells were rescued by M13KO7 helper phage and phage libraries were constructed.The size of antibody libraries is 2.2×106.Following the construction of phage display scFv libraries,the recombinant phage displaying scFv were enriched and identified.There are 26 clones against ENR generated in this study.Keywords：veterinary drug;enrofloxacin;single chain antibody;phage display techniques;hapten3|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To detect nitrofurans in feeds,a high performance liquid chromatography (HPLC) method for determination of nitrofurans,such as Furacillin,Nitrofurantion,Furazolidone,and Furaltadone,was established in this study.Nitrofurans in feeds was extracted by acetonitrle,concentrated extraction was cleaned up with HLB solid phase extraction (SPE) column.Nitrofurans were separated on Water Sunfire C18 column with UV detector 365 nm,using acetonitrile and ammonium acetate buffer as mobile phase.The results showed that the nitrofurans standard curve regression coefficient is above 0.9997,and the linearity range is 0.2~30.0 μg/mL.The average recoveries of nitrofurans ranged from 70%~98%,with RSD below 10%.The detection limit of Furacillin,Nitrofurantion,Furazolidone and Furaltadone was 0.020,0.020,0.020 and 0.100 μg/mL,respectively;and the quantitation limit was 0.50,0.50,0.50 and 1.00 mg/kg,respectively.This method exhibits uncomplicated operation,excellent linearity,high sensitivity and superior reproducibility for determination of nitrofurans residues in formula feed,concent-rate feed and premixes feed.Keywords：feeds;HPLC;solid-phase extraction;nitrofurans4|11|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Isomalto-oligosaccharide was conjugated to WPI by means of Maillard reaction to form WPI-isomalto-oligosaccharide.After the protein and sugar of different mass ratio reacting for different time,the changes of antigenicity of α-LA and β-LG were estimated by indirect competition ELISA.The results indicated that the glycosylation of WPI could reduce the antigenicty of α-LA and β-LG.The different effects on the antigenicity of α-LA and β-LG were observed under different reaction times and mass ratios.Under the optimal mass ratio of protein and sugar of 1∶4 and the optimal reaction time of 24 h,the antigenicity of α-LA decreased from 25.67 to 9.33 μg/mL and the antigenicity of β-LG decreased from 97.82 to 28.25 μg/mL.Keywords：whey protein;isomalto-oligosaccharide;glycosylation;antigenicity2|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In this paper,litchi juice was used to investigate the loss of soluble solid by ice crystal entrainment and the influence on the growing rate of ice crystals during freeze concentration,based on which the mechanism of formation of ice was studied.Based on the analysis of the freeze concentration kinetic model established,authors utilized the phase-field model theory,which has been widely used in the metal microscopic structure field at home and abroad,to stimulate the ice crystal growth.The results showed that the growing rate of ice was proportional to the mass of ice in the juice and was inhibited by the maximum mass of ice crystal.The result also showed that branches were grew out from round ice crystals with the increasing of freezing time and cooling rate;the more the branches,the more ice crystals entrainment,which resulted in the more loss of soluble solid in juices.Keywords：litchi;freeze concentration;ice crystal growth;kinetic model;phase-field model2|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the working performance and reduce the power consumption,a combine machine SGTN-180 is designed.The structure design and working characteristics of the combine machine are introduced.The configuration of the double roller position and the design of the power transfer system were mainly analyzed.This combined machine works with a special working pattern that has a front roller forward rolling and a rear roller reversing rolling.The front roller chops the straw and sends the crushed straw to the rear roller.The rear roller breaks the soil and returns the straw-soil mixture to the ground.The experimental results indicate that the combined straw returning-rotary tillage-fertilization machine has a fine working quality,which is characterized by the quality indexes as follows:vegetation coverage 94.8%,soil broken rate 93.1%,surface smoothness after working 0.4 cm,stability coefficient of tillage depth 97.2%,and a banding distribution of fertilizer mixed with soil in depth of 2-11 cm.Keywords：combined machine;double roller rotary tillage;straw returning;fertilization6|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：At present,few research reports on hydraulic calculation and hydraulic characteristics of field pipe network in subsurface drip irrigation (SDI) can be found in China.While these limited studies could not meet the requirements of engineering design.The mathematical model for hydraulic calculation in SDI filed pipe network was established based on former experiments and mathematical model of hydraulic calculation in SDI laterals.Using the model the hydraulic characteristics values in SDI field pipe network can be numerically solved under various conditions of uniformity slope,homogeneous soil,constant capillary diameter and constant space of submain pipes and laterals.Calculating results of the examples showed that the error s was less than 1/1 000,which is accurate enough to meet the needs of practice.Keywords：drip irrigation;field pipe network;hydraulic calculation;numerical simulation5|10|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A remote monitoring and control system based on 3G+VPN was designed and implementation to meet the remote video monitoring requirement in protected agriculture.It provides a sufficient video bandwidth and cheap wireless network access solutions.Results show that the system has characteristics of high universality,low cost,good expansibility and high reliability;and can be easily applied to the sites of protected agriculture,where there is no wire network connected to Internet,to meet the needs of remote monitoring and control.Now this system has been put into use in school experimental base,through which we can monitor environmental parameters remotely,control base server device,and watch the smooth clear real-time video (video server code rate for 512 kbit/s preset).Keywords：facility agriculture;3G;VPN;remote monitor and control2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to provide guidance for practical application in the remediation of groundwater pollution,the influencing factors of reduction of hexavalent chromium from solution were studied by batch experiment at laboratory scale,such as pretreated,amount of iron,initial pH and cation.The results showed that hexavalent chromium was removed quickly and effectively by zero valent iron,removal mechanism was redox and coprecipitation;the removal ratio was effected by the pretreatment with acid and nickelaqe,the amount of iron,initial pH and cation;Fe2+ could be used as an indicator for complete reduction of hexavalent chromium in the acidic condition.Keywords：zero valent iron;hexavalent chromium;groundwater;redox;coprecipitation2|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Agricultural technology is an inexhaustible motive force for agricultural development,and the implementation of agricultural technology subsidy policy and its effect have caused comprehensive attentions from all parts of the society.The purpose of this article is to analyze the effect of agricultural technology subsidy.In this paper,a systematic analysis was made on the implementation of agricultural technology subsidy policy based on the survey in Henan and Jiangsu Province,and a Logit model was used to estimate the effect of the subsidy variables.The conclusion is that age, education level of the household and machine quality are obviously different at 1% level,and these variables are positively correlated to the adoption of agricultural technology,while the subsidy as a variable is not significant.At last,some recommendations are given,such as to enhance advocacy efforts of agricultural technologies and their subsidy polices,to improve agricultural technology itself,and to strengthen technical guidance,etc.Keywords：agricultural technology;subsidy policy;returning straws to soil;Logit model;policy effect2|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the predictability of agro-product market price and to take measures to reduce price fluctuation,this study selected the wholesale price of tomatoes as an object and employed the five methods,the seasonal dummy variables,the Census X12 method,the moving average method,the Holt-Winters seasonal exponential smoothing method and the SARIMA,to establish short-term forecasting models.A combination forecasting model was established and the weights used in the model were calculated according to the single model prediction error.The results showed that the error of single model fluctuated greatly and the accuracy declined with longer forecast period.Mean absolute percent error (MAPE) of the five single models in forecasting evaluation for 2009 is about 10%,of which the Holt-Winters seasonal exponential smoothing model has the lowest MAPE of 6.81%.When forecast period is ahead of 3 months,the accuracy of the SARIMA model was the highest which was more than 95%.On the basis of empirical analysis,this study used the combination forecast method to predict the tomatoes market price in 2010.Keywords：agro-product;market price;forecasting model1|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
