2018, 37(2):1-8.
Abstract:The promoter sequences of nodA,nodB,nodD were cloned based on the genomic information of Mesorhizobium loti MAFF303099 and fused with the reporter gene lacZ to construct the nod-lacZ fusion separately. Then these fusions were separately transformed into M. loti MAFF303099 and Rhizobium sp. NGR234 to detect the expression of these nod genes after induced by Lotus japonicus root extract (RE). The results showed that there was no expression of nodA when treated with root extracts.RE induced expression of nodB and nodD1,but showed upregulation of just 2-3 times. nodD2 expressed constitutively in M. loti MAFF303099.Neither of these induced the expression of nodA in M. loti MAFF303099 induced by 5 different flavonoid compounds separately,but the expression of nodA was detected in NGR234 strain treated by Luteolin.
2018, 37(2):9-15.
Abstract:Somatic embryogenesis receptor protein kinase gene (SERKs) belongs to the family of genes encoding LRR receptor kinase and participates in multiple life activities including plant growth,development and immunity.Eight homologous genes (LjSERKs) were identified from Arabidopsis thaliana AtSERKs gene sequence to explore the function and mechanism of SERKs gene family in the process of nodule symbiosis.Using the CRISPR-Cas9 genome editing and hair root transformation technique,the different genes of the LjSERKs family were knocked out separately.The effects on the symbiotic nodule phenotype were observed and analyzed.The results showed that the number of nodules was not different significantly from that of the control plants after knockouting LjSERK2,LjSERK3,LjSERK6 and LjSERK7.The number of nodules was significantly decreased after knockouting LjSERK8.It is indicated that LjSERK8 is involved in the nodule symbiosis process and there may be functional redundancy between other genes in the family.
2018, 37(2):16-22.
Abstract:Mesorhizobium loti MAFF303099 was used to construct a random mutant library with transposon Tn5-sacB mutagenesis technique.A total of about 10000 independent mutants were obtained.A method for rapidly identifying mutants from the library was established.The mutant of the symbiotic nodule gene nodB was identified through screening the mutant library.The results showed that the transposon Tn5-sacB was inserted into the genome DNA of all the mutants in the mutant library,with the tri-parental mating transformation efficiency of 3.75×10-5.The MAFF303099 mutant of nodB did not form nodules on Lotus japonicus roots comparing with the wildtype.
2018, 37(2):23-27.
Abstract:The mature nodules of Medicago truncatula (A17) were used to construct a cDNA library with Gibson cloning technique and SMART cDNA library construction technique.The result of library testing showed that the transformation efficiency of the library was 7.74×105 transformants/3 μg pGADT7-Rec-New.Some colonies were randomly picked to run PCR.Results showed that the inserted DNA fragment size was ranged from 0.5 kb to 2.0 kb,with the recombinant rate of 91.7%.The cDNA library was stored as plasmid.This method can be used to construct library for yeast one or double hybrid and other plasmid library.The library was used to find protein(TF) that can interact with the DNA fragment of interest and some TFs were obtained.
2018, 37(2):28-33.
Abstract:Ten key genes in symbiosis signaling from Lotus japonicuswere controlled under ten different individual promoters expressed in roots of Arabidopsis thalianawith biotechnology and synthetic biology approaches.Two multigenes vectors,pUNS6 containing 6 genes and pDNS4 containing 4 genes,were constructed respectively to transform Arabidopsis thaliana.The result of complement assay showed that ten genes controlled in CaMV35S promoter were able to restore symbiotic function of relative genes mutant in leguminous plants with hairy root transformation.The pUNS6 and pDNS4 were transformed into Arabidopsis with Agrobacterium tumefaciens-mediated inflorescence infection respectively.The result of identifying the transgenic T0,T1 and T2 plants by PCR and RT-PCR showed that those of foreign symbiotic genes were stably existed on genome and were able to express at the RNA level in Arabidopsis thaliana.
李健 , 杜成忠 , 王露蓉 , 邢永秀 , 李杨瑞 , 杨丽涛
2018, 37(2):34-42.
Abstract:In order to analyze the drought resistance of sugarcane △1-pyrroline-5-carboxylate synthase gene (SoP5CS),SoP5CS was transformed into tobacco using Agrobacterium-mediated leaf discs method. Four transgenic tobacco lines with low copy numbers were screened for drought stress experiment. The results showed that both the relative expression levels of SoP5CS and its encoded protein were the lowest in T9 transgenic tobacco line under drought stress.Compared with T9,the relative expression level of SoP5CS in T1,T4 and T6 lines were 9.02-fold,3.93-fold and 8.51-fold while the protein level of SoP5CS in T1,T4 and T6 lines was 2.22-fold,3.91-fold and 1.36-fold,respectively.Results of further analyses showed that the contents of proline and ABA in the four transgenic lines were all significantly higher than those in the control.The contents of proline and ABA in T1 and T6 lines were higher than those in the other two lines. The MDA content in the control was significantly higher than that of the transgenic plants.The accumulation of MDA was the lowest in T1 line. The P5CR and P5CS activities were different between the control and transgenic plants.The activities of both enzymes in T1 and T4 lines were nearly the same as those in the control,significantly higher than those in T6 and T9 lines. The CAT activity was the highest in T6 line,which in the other transgenic lines significantly higher than that of the control. SOD activity in all the transgenic lines was significantly higher than that in the control,with which in T4 and T6 lines being relatively higher. The relative water content in the leaves of the transgenic lines was significantly higher than that in the control,while the chlorophyll reduction was lower. The result of RA comprehensive analysis showed that the drought resistance of T6 line was the best,followed by the T1 line,indicating that drought resistance of SoP5CS gene is strong.
石洪芳 , 易志杰 , 杨特武 , 赵思明 , 周强 , 周欣 , 杨罗浩
2018, 37(2):43-49.
Abstract:A newly bred rice cultivar with high anthocyanin content,Gangteyou 37,was used to study the effects of nitrogen (N) and potassium (K) application patterns on the yield and the nutrition quality of dehulled rice under the total application of N 159 kg/hm2,P2O5 67.5 kg /hm2 and K2O 67.5 kg/hm2 in the field.Results showed that the highest grain yield was obtained when all K was applied as basal fertilizer,60% of N used as basal fertilizer,10% of N applied at tillering stage and 30% of N at spikelet developing stage.Appropriate fertilizer application increased the effective panicles per area,therefore,increased the yield.The fertilizer application patterns rarely affected the contents of amylose,amylopectin and anthocyanin,but proper amount of N applied at the spikelet developing stage increased the content of soluble sugar in dehulled rice.The content of crude fat in dehulled rice was increased by supplying K at the later developmental stage under the same N application pattern.Gama-aminobutyric acid (GABA) tended to increase when N was applied at the spikelet developing stage under the same K application pattern.When all K was applied as basal fertilizer,the content of free amino acid increased first and then decreased with the increase of N application rate at the spikelet developing stage.When 60% of K was used as basal fertilizer and 40% as spikelet developing fertilizer,the content of free amino acid in dehulled rice increased with the increase of N application rate at the spikelet developing stage.Applying N significantly increased the content of crude protein in dehulled rice,but its changes were inconstant under different K application patterns.It is indicated that all K applied as basal fertilizer,60% of N used as basal fertilizer,10% of N applied at tillering stage and 30% of N at spikelet developing stage is suitable to improve rice yield and nutritional quality,and can be used as appropriate fertilizer application pattern for Gangteyou 37.
2018, 37(2):50-55.
Abstract:In a previous study,six autophagy-related genes were identified during sclerotial development of Rhizoctonia solani AG1-IA using RNA-seq technology.In order to reveal the expression patterns of these genes during sclerotial development of R. solani AG1-IA ,quantitative real-time PCR (qRT-PCR) was performed.The results showed that expression of the serine/threonine kinase,ssp1, ATG13 and Vam6 genes was significantly up-regulated at the sclerotial initiation stage,but down-regulated at the sclerotial maturation stage.However,the serine/threonine-protein phosphatase gene and serine/threonine kinase receptor-related protein gene showed a significant decrease during sclerotial development of R. solani AGI-IA.The expression patterns of these genes obtained by qRT-PCR were in accordance with the results obtained by RNA-seq,which indicated that the results of RNA-seq were reliable.This study also showed that autophagy-related genes were highly regulated during sclerotial development,and may play an important role in sclerotial development.
2018, 37(2):56-63.
Abstract:To elucidate the expression pattern and effect of temperature stress of thioredoxin peroxidase inHeortia vitessoides (HvTpx),the cDNA sequence of HvTpx was screened from the transcriptome of the adult H. vitessoides. The complete open reading frame (ORF) of HvTpx is 588 bp in length,encoding 195 amino acids. HvTpx is a typical member of the 2-Cys Tpxs family,which showed the highest similarity with Helicoverpa armigera(87%) and shared similarity above 75% with other insects.H. vitessoides and H. armigera were clustered in the same branch in the phylogenetic tree based on insect thioredoxin peroxidase amino acids. The results of RT-qPCR revealed that the expression levels of HvTpx were higher in adult than in other stages during development. In larvae,HvTpxhad the highest expression level in midgut. HvTpx showed the highest expression level in the abdomen and lowest in the foot in adults. The expression levels of HvTpxat 0℃,10℃ and 35℃ were significantly increased than that in the control (25℃),indicating that expression of HvTpx could be induced by temperature. The results provide further information in understanding the molecular mechanism of H. vitessoides response to temperature stress.
2018, 37(2):64-70.
Abstract:The pedogenic carbonate nodules formed during the Holocene in the Wugong section on southernmost Loess Plateau were selected to study the mineralogical and acid-leachable elemental composition of carbonate nodules together with the specific properties including grain size and distribution of organic matter and carbonate in >250 μm, 50-250 μm and <50 μm nodules, to understand the formation of carbonate nodule and assess its elemental enrichment characteristics. The results showed that the pedogenic carbonate nodules were cemented by mainly >250 μm and <50 μm nodules. Pedogenic carbonate first deposited on the surface of clay and fine silt and then soil pores between the grains were gradually filled by pedogenic carbonate along with the deposition resulted in the formation of carbonate nodules and continued growing. The carbonate content in the nodules increased sharply with the increasing size of nodules and consequently diluted and decreased the organic matter content. The grain composition became coarse and the content of clay minerals decreased with increasing size of carbonate nodules. Elemental composition of the acetic acid-leachable fraction in each size of carbonate nodules was characterized by extremely high Ca concentration (61.03-207.36 g/kg) directly related with carbonate content. It is indicated that calcium carbonate was the dominant form of carbonate in the nodules. The acetic acid-leachable fraction is composed of certain amounts of Si (8.90-10.70 g/kg) and Al (2.78-5.06 g/kg) from amorphous phases of pedogenic origin, K (3.34-4.32 g/kg) and Mg (2.22-3.64 g/kg) from clay minerals, and a small amount of Na (0.70-0.85 g/kg) from highly soluble salts.
文健 , 刘桂琼 , 姜勋平 , 周广生 , 傅廷栋 , 刘辰晖 , 种玉晴
2018, 37(2):71-75.
Abstract:The above-ground parts of forage rape were collected,weighed and dried to measure the general nutritional ingredients at the seedling,bolting and flowering stages. Forage rape were harvested at the end of the flowering stage and ensiled to produce fermented total mixed ration (FTMR). Two hundred 2-month-old Hu sheep were randomly divided into two groups. One group were fed with forage rape FTMR and the other were fed with maize silage TMR. Ten rams were slaughtered to assess carcass characteristics and meat quality after three months. The results showed that the seedling,bolting and flowering period were from 8 to 98 d,99 to 146 d,and 147 to 180 d,respectively. The fresh weight reached the peak at 180 d. The crude protein and fat content increased during forage rape development,reached the top value at 180 d,making the peak harvest value of forage rape at 180 d. The weight gain,dressing percentage,carcass meat rate,backfat thickness,and eye muscle area of rams fed with forage rape FTMR were not different from those fed with maize silage TMR. However,feed conversion ratio (FCR) and profit of the forage rape group was significantly higher than that of the maize silage group. In conclusion,the best harvest time of forage rape was at 180 d in Hubei Province and the forage rape FTMR had no negative effect on growth and carcass characteristics of Hu sheep,and cost lower compared with maize silage TMR. Therefore,the forage rape can be applied in finishing lambs,which is beneficial for relieving stress of shortage feed in winter and reducing feed cost.
2018, 37(2):76-82.
Abstract:“Huangyou No.1” (Pelteobagrus vachelli♂×Pelteobagrus fulvidraco♀) is a new freshwater fish breed with advantages of rapid growth and strong resistance to disease.To appraise the nutritional value of “Huangyou No.1”,we analyzed the composition and content of amino acids and fatty acids in the muscle of “Huangyou No.1” and compared it with that of its parental species.A total of 17 amino acids were detected in the muscle of the three kinds yellow catfish.The contents of the total amino acids,total essential amino acids and total flavor amino acids were highest in the muscle of “Huangyou No.1” among the three kinds of yellow catfish.The content of essential fatty acids in the muscle of “Huangyou No.1” was 22.85%,which was close to that of yellow catfish and slightly lower than that of darkbarbel catfish.These results showed that “Huangyou No.1” has significant nutritional advantages in fatty acids and amino acids.
2018, 37(2):83-88.
Abstract:To investigate the antimicrobial activities of the Streptommyces galilaeus AF1 metabolites on Streptococcus agalactiae,a spectrophotometer and counting plate colony was used to detect the effect of the metabolites against S. agalactiae and a comparative test on the efficacy with certain antimicrobial agents was conducted. The results showed that the metabolites ofS. galilaeus AF1 have strong effects against S. agalactiae and the minimal inhibitory concentration was 38 μg/mL with the does-time-effect relationship. The scanning electron microscopy results indicated that the cell walls of S. agalactiae were ruptured severely after being treated with the metabolites. The 96 h LC50 value for zebrafish were 27.44 mg/L and 35.44 mg/L by static method and feeding method,respectively and the acute toxicity was low. This study showed that the metabolites of S. galilaeus AF1 have good antibacterial activity against S. agalactiae and provides a new clue for prevention and control of S. agalactiae.
2018, 37(2):89-95.
Abstract:Xiaogan pearl glutinous rice produced in Hubei Province was used to make sweet rice wine with four different kinds of starter brands (Xiaogan,Mipopo,Suzhou,Angle).Four kinds of sweet rice wines were evaluated by sensory evaluation.The content of chemical components,small molecular sugars,organic acids and free amino acids were detected.Results showed that there were significant differences in most nutritional ingredients of four fermented sweet rice wines made by different starter brands.The content of total sugar and reducing sugar in sweet rice wines made by Angle and Suzhou brand starters were more than that made by Mipopo and Xiaogan brand starters.The content of small molecular sugar and organic acid in Angle and Mipopo sweet rice wines were higher than that in Xiaogan and Suzhou sweet rice wines.Xiaogan fermented sweet rice wine performed well in free amino acid analysis,followed by Mipopo fermented sweet rice wine.Mipopo sweet rice wine obtained a high score of sensory evaluation,followed by Suzhou yeast fermented rice wine.Because of its high sensitive to taste compound,electronic tongue was used to identify different rice wine products.A predictive model of probe response value and taste sense based on the electronic tongue was established.
2018, 37(2):96-102.
Abstract:A new rapeseed oil seedling/weed detection method based on visual-attention model was put forward.The RGB images for the rapeseed oil seedling and weed in the seedling rapeseed oil field were obtained.Series of feature saliency using an improved Itti model in terms of the distribution characteristics of the original images were mapped.The ROI using region growing method were extracted.We calculated the shape and texture feature parameters of the regions segmented before and put them as the input of SVM used to identify seedling rapeseed oil regions.The weed regions were obtained by combining the original images with the seedling rape regions using a logical operation.The results showed that the correct segmentation rate,false segmentation rate and error segmentation rate of the proposed method was 92.46%,3.26% and 7.54%,respectively.It is indicated that the proposed method is better than the other two image segmentation methods.Using shape,texture,comprehensive and specifically selected feature parameters as the input,the classification rate of RBF-SVM was 96.00%,94.29%,100.00% and 96.00%,respectively.
杨锴 , 段宏兵 , 宋波涛 , 陈志鹏 , 余参参 , 黄翔 , 梅红成
2018, 37(2):103-109.
Abstract:Metering device as key components of potato mechanization planting has problems including the high multiple index and missing index,heavy manual labor intensity,poor universality and other problems.A new type potato seed-metering device with triangular chain and half-cup was designed.The main structure,working principle and related parameters of the device was introduced in detail.An orthogonal experiment was carried out to understand factors including the driving wheel speed,the inclination of the seed-clearing device and the size of cup affect the performance of the seed-metering device.The parameters were optimized and verified.The results showed that the best performance was obtained when the revolving speed of the driving pulley was 37.5 r/min,the inclination of the seed-clearing device was -5° with the biggest size of cup.The qualified index,the multiple index and the missing index is 93.74%,3.99%,and 2.27%,respectively.The performance of metering device under the condition can meet working performance requirements of the potato seeder.It will provide a theoretical and technical reference for studying and designing seed-metering device of potato seeder.
2018, 37(2):110-116.
Abstract:A kind of air suction type Artemisia selengensis leaves removing machine was designed to solve the problems of low efficiency and high labor cost of artificially removing leaves of A. selengensis,which consists of the transport part and removing leaves part. Automatic opening and closing clips,automatic removal of leaf components and other key components were designed. The relevant motion parameters were analyzed to obtain the motion relation between the components. The prototype was manufactured and tested with orthogonal test. The optimal motion parameters of the prototype obtained are as follows:the speed of the automatic opening and closing clip is 0.120 m/s,the cam speed is 50 r/min,and the axial pressure of the axial fan is 100 Pa. Results showed that the entrainment rate of the machine was 98% and the qualified rate of removing leaves was 89% with a good practicality. It will provide a new direction for the studies on removing A. selengensis leaves mechanically.
常正 , 黄汉英 , 涂群资 , 李路 , 赵思明 , 熊善柏
2018, 37(2):117-121.
Abstract:Crucian carp,grass carp,bream and yellow catfish were used to investigate the force conditions for live fish under the process of transportation and obtain force curve of transportation for live fish through testing conditions of different road and vehicle including straight line driving,over deceleration belt and uniform circular motion.The force value curve was filtered and the values of mechanical characteristics were extracted and analyzed.The results showed that there was a significant difference of affecting values of partial mechanical characteristics under the different kinds of fish and speed of vehicles and speed of acceleration.Under conditions of the three different driving,uniform circular motion had the greatest impact on the maximum force.It will provide a foundation for studying stress mechanism of live fish carried by vehicles under conditions of different transportation.
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