Acta Agriculturae Zhejiangensis

Cloning and expression analysis of GmDof1.5 in soybean under abiotic stress

HE Jiaqi, ZHAI Ying, ZHANG Jun, QIU Shuang, LI Mingyang, ZHAO Yan, ZHANG Meijuan, MA Tianyi

2021, 33(1): 1-7. DOI: 10.3969/j.issn.1004-1524.2021.01.01

Abstract ( 2042 )

HTML ( 1275087456 )

PDF (817KB) ( 2186 )

Dof transcription factors play an important regulatory role in plant growth and development and response to abiotic stress. A soybean Dof transcription factor GmDof1.5 with unknown function was cloned through RT-PCR, which was located on chromosome 15 of the soybean genome. The ORF of GmDof1.5 was 540 bp, which encoded 179 amino acid residues with molecular weight of 20.15 ku and isoelectric point of 9.82. Prediction of protein sequence showed that GmDof1.5 contained a typical Zf-Dof binding domain and a large number of phosphorylation sites. Phylogenetic analysis indicated that GmDof1.5 of soybean was highly homologous to SsDof4 of Spatholobus suberectus. Quantitative real-time PCR showed that the expressions of GmDof1.5 were induced by ABA, drought, salt, high temperature and cold stresses to different degrees. Especially, the response of GmDof1.5 to high temperature was the most obvious.

Figures and Tables | References | Related Articles | Metrics

Effects of different tillage depth and amount of straw returned to the field on maize growth under drip-irrigation

LIU Genhong, XUE Yinxin, ZHANG Qian, ZHOU Jiarui, MAI Xiaofeng

2021, 33(1): 8-17. DOI: 10.3969/j.issn.1004-1524.2021.01.02

Abstract ( 1045 )

HTML ( 8129664 )

PDF (860KB) ( 2029 )

Drip irrigation has gradually become a new resource-saving cultivation method in the irrigation area of Ningxia; however, the depth of tillage and the amount of straw returned to the field under drip irrigation were not clear. The experiment was conducted to study suitable tillage depth and the level of returning straw to field under drip irrigation. Tianci No. 19 was the test maize material, and the split-plot experiment design was adopted. The main plot was tillage depth with three levels of 0.25-0.30 m, 0.30-0.35 m, 0.35~0.40 m, and the amount of straw returned to field was quarter, one third and one half of the straw amount returned to field in conventional cultivation. The results showed that the effects of different treatments on the growth index and yield of maize were different, and the difference between the treatments was significant (P<0.01) at the level of 0.30~0.35 m of tillage depth and one third of the straw amount returned to field. In this treatment, the soil temperature of 0-0.2 m at seedling stage increased obviously, the maximum difference was 1.5 ℃, the increase rate was 8.6%, the photosynthetic rate (PSA) at silking-filling stage was 34.5% higher than the lowest treatment, the 100-grain weight was 6% higher than the lowest treatment, the filling rate (GFA) at 20 days after pollination was 26.9% higher than the lowest treatment, the yield was 14 781.9 kg·hm^-2, and the yield was 16.3% higher than the lowest treatment. But different treatments had different effects on plant height, leaf area index (LAI) and ear diameter. The treatment one half amount of straw returned to field and 0.25-0.30 m of tillage depth had significant effects on plant height, LAI at jointing stage and ear diameter. It was concluded that the main field growth characters were good at the level of 0.30-0.35 m tillage depth and one third of the straw amount returned to the field. The ear length, ear diameter and 100-grain weight of ear characters were all better than other treatments, and the yield was the highest, which was suitable for promotion in irrigation area.

Figures and Tables | References | Related Articles | Metrics

VP1 protein of encephalomyocarditis virus inhibits type I IFN signaling pathway and promotes virus proliferation in vitro

HAN Yumei, XIE Jingying, BI Yingjie, XU Shujuan, FENG Ruofei

2021, 33(1): 18-26. DOI: 10.3969/j.issn.1004-1524.2021.01.03

Abstract ( 893 )

HTML ( 20 )

PDF (2147KB) ( 1840 )

Encephalomyocarditis virus (EMCV) is an important zoonotic pathogen. In order to preliminarily study the molecular mechanism of EMCV mediated innate immune response, this study cloned VP1 protein into eukaryotic expression vector pCMV-HA, transfected it into HEK293 cells to make it overexpress in cells. The effects of VP1 overexpression on IFN-β expression and RLRs signaling pathway-related factors and downstream stimulation gene expression were detected by ELISA and real time fluorescence quantitative PCR. Results showed VP1 could significantly inhibit IFN-β expression. Further study found that VP1 could significantly inhibit the mRNA level of EMCV-induced RLRs signaling pathway-related factors, and with the expression of VP1, MAVS protein expression was significantly reduced, but had no effect on the expression of MDA5. Therefore, the data of this experiment preliminarily showed that VP1 protein could inhibit the expression of type Ⅰ IFN gene expression and block its downstream signaling pathway by inhibiting the expression of MAVS.

Figures and Tables | References | Related Articles | Metrics

Construction and identification of nanobody T7 phage display library

XU Hai, WANG Jian, GUO Changming, DONG Hongyan, DENG Bihua, HOU Jibo

2021, 33(1): 27-33. DOI: 10.3969/j.issn.1004-1524.2021.01.04

Abstract ( 1019 )

HTML ( 28 )

PDF (4210KB) ( 1811 )

To construct a high-quality natural alpaca nanobody phage display library by strategy optimization, and systematically identified the quality of the library, the total RNA was isolated form peripheral blood mononuclear cell of 6 alpacas and then reverse transcripted into cDNA. The VHH gene was amplified and insert into plasmid and T7 select 415-1b vector, respectively, to construct plasmid and phage display library. The phage library was identified by volume calculating, propagating stability testing and sequencing. The expression of nanobody was tested by Western-blot, and the structure of phage particles were detected by electron microscopy. Results showed that the effective volume of phage library was 2.73×10⁹ PFU, and VHH nanobody was successfully displayed on T7 phage surface in high copy number. Sequence analysis showed that VHH nanobody had high homology with alpaca antibody. Recombinant phage presented intact particle structure the same as the donate T7 select 415-1b phage. However, during continuous passage a part of recombinant phages would lost the insert VHH gene, which indicated that only lower-generation phage library could be used for affinity screening.

Figures and Tables | References | Related Articles | Metrics

Prokaryotic expression and antibody preparation of full-length and N-terminal half of SpTrz2 protein in Schizosaccharomyces pombe

LIU Jinyu, HUANG Ying

2021, 33(1): 34-42. DOI: 10.3969/j.issn.1004-1524.2021.01.05

Abstract ( 821 )

HTML ( 27 )

PDF (2376KB) ( 1955 )

To bioinformatically analyse the biological characteristics of Schizosaccharomyces pombe SpTrz2 protein, both the full-length and the N-terminal half of S. pombe sptrz2 gene were amplified by PCR and inserted into pET-28a(+) expression vector through NdeⅠ and XhoⅠ restriction enzyme sites. The recombinant plasmids were transformed into Escherichia coli BL21(DE3) and the transformants were induced by IPTG. Then recombinant proteins were purified by the way of SDS-PAGE gel slices. Polyclonal antibodies were prepared by immunizing New Zealand white rabbit using the purified recombinant proteins. The specificity of antibodies was tested by Western blotting. The results showed that SpTrz2 was a transmembrane protein with three transmembrane domains and contained multiple B cell antigen epitopes. SDS-PAGE analysis suggested that the full-length and the N-terminal half of SpTrz2 protein (SpTrz2 and SpTrz2N) with a relative molecular mass of about 75.99 ku and 44.77 ku, respectively, mainly existed in a form of inclusion body. The Western blot analysis showed that polyclonal antibodies of SpTrz2 and SpTrz2N could specifically recognize natural SpTrz2 protein. In this study, recombinant SpTrz2 and SpTrz2N protein were successfully expressed and purified, and their polyclonal antibodies were prepared. All above results could provide experimental evidence for the study of biological function of SpTrz2 protein.

Figures and Tables | References | Related Articles | Metrics

Structures and characteristics of 103 plasmids carrying mcr gene

TANG Biao, CHANG Jiang, HU Ji, QIAN Mingrong, XIA Xiaodong, YANG Hua

2021, 33(1): 43-51. DOI: 10.3969/j.issn.1004-1524.2021.01.06

Abstract ( 850 )

HTML ( 19 )

PDF (2380KB) ( 1717 )

Colistin is the last first-line drug in the treatment of carbapenem-resistant pathogens infection. However, the widespread of plasmid mediated mcr gene which involved colistin resistance had reduced the effectiveness and posed a threat to public health. The purpose of this study was to summarize the complete plasmids bearing mcr and explore plasmid characteristics that might affect the spread of colistin resistance. A total of 103 complete plasmid sequences carrying mcr which were released in GenBank from 2015 to 2018 were analyzed. The results showed that the main plasmids were from China and Escherichia coli was the main host. IncI2 and IncX4 were the most important replicon types, and IncHI2 was the dominant type of plasmids with multiple resistance genes. Meanwhile, 95.14% of the plasmids contained antibacterial biocide or heavy metal resistance genes. Except for ISApl1, the frequency of IS26 was the highest. 18.45% of them had conjugated transfer elements, including oriT, relaxase, T4CP and T4SS. This study emphasized the co-selection of antibiotics and heavy metals, which provided landscape for better control of colistin resistance.

Figures and Tables | References | Related Articles | Metrics

Effects of different rootstocks on growth and fruit quality of Tiangong Cuiyu grape

CUI Pengfei, WEI Lingzhu, CHENG Jianhui, XIANG Jiang, LI Mingshan, WU Jiang2,

2021, 33(1): 52-61. DOI: 10.3969/j.issn.1004-1524.2021.01.07

Abstract ( 881 )

HTML ( 1480605695 )

PDF (816KB) ( 2113 )

In order to study the effects of different rootstocks on the growth and fruit quality of Tiangong Cuiyu grape in hot and humid area of South China, and screen the rootstock-scion combinations with good comprehensive quality, 7 kinds of rootstock were grafted with Tiangong Cuiyu, and self-grafted Tiangong Cuiyu were set as the control. The growth, economic characteristics and fruit quality of the plants were investigated and measured, the differences of the rootstock-scion combinations were analyzed, and the fruit quality of grape rootstock-scion combination was evaluated comprehensively by principal component analysis. The results showed that the flowering period of grafted plants with the rootstock of SO4, 5BB and Dogridge were earlier than that of the self-grafted plants. All 7 kinds of rootstocks could improve the fruiting rate. The yield per plant of grafted plants of SO4, 5BB and Macadams were higher than that of self-grafted plants, increasing by 1.9%, 2.4% and 10.0%, respectively. There was no significant difference in the thickness ratio of grafted plants of 5BB, Dogridge, Kangzhen No. 5, 101-14 and Macadams. The rootstocks of SO4, 5BB and Macadams could all improve the quality of grafted plants. The fruit hardness of grafted plants with 5BB was 4.07 N on average, which was 60.9% higher than that of self-grafted plants. The total sugar content of grafted plants with SO4, 5BB and Macadams was higher than that of self-grafted plants. The sucrose content of grafted plants with 5BB was higher than that of self-grafted plants, with an average of 7.97 mg·g^-1, which was 33.05% higher than that of self-grafted plants. According to the principal component analysis, 5BB was the best rootstock suitable for Tiangong Cuiyu grape.

Figures and Tables | References | Related Articles | Metrics

Cloning and expression analysis of PpSAMS gene of Pleurotus pulmonarius

WANG Weike, LU Na, YAN Jing, SONG Jiling, YUAN Weidong, ZHOU Zufa

2021, 33(1): 62-68. DOI: 10.3969/j.issn.1004-1524.2021.01.08

Abstract ( 1035 )

HTML ( 40 )

PDF (1763KB) ( 2022 )

Based on the high-throughput transcriptome sequencing of different growth stages of Pleurotus pulmonarius samples, the full-length gene of S-adenosylmethionine synthetase was obtained by analysis and screening. In order to explore the function and expression difference of PpSAMS in the formation of primordium of Pleurotus pulmonarius after low temperature stimulation, the gene of PpSAMS was cloned and analyzed systematically in order to explore the function and expression difference of PpSAMS in the primordium formation of Pleurotus pulmonarius after low temperature stimulation. The expression of the gene in different growth stages was analyzed by real time fluorescence quantitative PCR. Bioinformatics analysis showed that PpSAMS gene was composed of 1 152 nucleotides and encoded 384 amino acids. It had the function of binding ATP and metal ions, and had the activity of S-adenosylmethionine synthetase. The phylogenetic tree analysis of amino acid sequence showed that the protein encoded by PpSAMS gene was closely related to Pleurotus ostreatus. Real time fluorescence quantitative PCR indicated that the expression of PpSAMS was the highest when the mycelium recovered to room temperature after low temperature induction (prophase of primordium formation). It might play an important role in the process of DNA methylation and primordium formation, and participate in the development of fruiting body.

Figures and Tables | References | Related Articles | Metrics

Preliminary study on identification of Dendrobium officinale from Zhejiang based on ITS2 and SNP technology

CHEN Wenqiang, WANG Xiaofu, CHEN Xiaoyun, PENG Cheng, XU Junfeng, CAI Jian

2021, 33(1): 69-76. DOI: 10.3969/j.issn.1004-1524.2021.01.09

Abstract ( 1008 )

HTML ( 22 )

PDF (3076KB) ( 2002 )

Dendrobium officinale is favored by consumers for its nutritional value and health benefits. However, it is difficult to distinguish and identify different varieties and different qualities of D. officinale. It is urgent to establish a fast, accurate and efficient identification method. In this study, 12 D. officinale from Zhejiang Province and 10 other Dendrobium were used, the DNA barcode ITS2 was selected, the amplification system for ITS2 was optimized, then the amplified products were sequenced. After sequence comparison and analysis, the specific SNP sites were obtained from DNA barcode ITS2 of D. officinale; specific primers designed for the SNP sites were verified by PCR, and a rapid identification method for SNP sites based on high-resolution melting curve (HRM) technology was established. The results showed that DNA barcode ITS2 could distinguish D. officinale from other Dendrobium. The rapid detection based on SNP realized the rapid identification of D. officinale, which provided a new concept and technical path for identification and quality control of D. officinale.

Figures and Tables | References | Related Articles | Metrics

Colonization of fluorescently labeled Bacillus amylolyticus WK1 in Carya cathayensis Sarg. and soil

GAO Jing, FANG Wei, GU Jiayue, YAN Shuxian, SHAO Shuai, LIANG Chenfei, QIN Hua, CHEN Junhui, XU Qiufang

2021, 33(1): 77-86. DOI: 10.3969/j.issn.1004-1524.2021.01.10

Abstract ( 1276 )

HTML ( 20 )

PDF (3144KB) ( 2057 )

In order to determine the colonization dynamics and the best way of Bacillus amylolyticus WK1 inoculation in hickory (Carya cathayensis Sarg.) and soil, electric shock transformation method was used to introduce green fluorescent protein (GFP) particles to construct the fluorescent labeled strain (GFP-WK1). The liquid GFP-WK1 was inoculated by leaf spraying, root irrigation and trunk injection, and the colonization number of GFP-WK1 strain was determined in soil, roots and leaves of hickory at regular intervals during 60 days. The liquid GFP-WK1 was added to soil with pH of 5.6, 6.8 and 7.9, respectively, in order to find the suitable soil pH for WK1 colonization. The results showed that GFP-WK1 could be colonized in both soil and inner tissues of hickory trees by leaf spraying, root irrigation and trunk injection, which indicated its good mobility between soil and hickory tree as well as inner tissues. The GFP-WK1 was maintained in the range of 10⁴-10⁶ CFU·g^-1 during 60 days. Compared with root irrigation and leaf spraying, GFP-WK1 strain was more stable in hickory tree and soil by trunk injection. The GFP-WK1 was more abundant in soil with pH of 6.8. The colonization number in hickory seedlings decreased in the order of roots>stems>leaves. It was recommended to inoculate GFP-WK1 by root irrigation in respect to colonization effect in tissue and the convenience of application in short-term, combined with adjusting soil pH to 6.8. For the long-term consideration, trunk injection was a better choice.

Figures and Tables | References | Related Articles | Metrics

Effects of processed petroleum-based horticultural mineral oils on settling behavior of Diaphorina citri Kuwayama (Hemiptera: Lividae)

HUANG Zhendong, PU Zhanxu, HU Xiurong, CHEN Guoqing, LYU Jia, ZHAN Hongmu

2021, 33(1): 87-95. DOI: 10.3969/j.issn.1004-1524.2021.01.11

Abstract ( 1342 )

HTML ( 24 )

PDF (802KB) ( 1792 )

In order to evaluate the control efficacy of petroleum-based horticultural mineral oils(HMOs)against Diaphorina citri Kuwayama (Hemiptera: Liviidae), the colonization rate of the adult Diaphorina citri on the citrus plants were investigated with four volumn fractions of HMOs in 0.25%, 0.5%, 1% , 2% and water control sprayed on the citrus seedlings in the closed space. Meanwhile, the control efficiency of HMOs on Diaphorina citri nymph were evaluated with the same experimental design. It was showed that when the adult Diaphorina citri were released after spraying HMOs on the citrus seedlings once, the number of adults/plant within 1 to 2 days and eggs/plant in 9 days significantly reduced (P<0.05); however, the control effect was not obvious in the later stage. The numbers of the adult Diaphorina citri per plant after spraying HMOs on the citrus seedlings twice was fewer than spraying once. When the adult Diaphorina citri were released after spraying 2% HMOs on the citrus seedlings twice, the colonization ratio of the adult Diaphorina citri was 0.15 after 22 days. Among the treatments that adult Diaphorina citri released after spraying HMOs on the citrus seedlings twice, spraying HMOs on the citrus seedlings before and after the release of adult Diaphorina citri, and the adult Diaphorina citri released before spraying HMOs on the citrus seedlings twice, the best treatment was the adult Diaphorina citri released before spraying HMOs on the citrus seedlings twice. The result of field trial showed that the control efficacy of spraying 1% and 2% HMOs on the Diaphorina citri nymph remained 100% within 2-14 days, the control efficacy of 0.5% HMOs treatment was between 87.15%-90.81%, the control efficacy of 0.25% HMOs treatment was between 25.81%-34.73%. 0.5%-2% HMOs provided excellent control efficacy on the Diaphorina citri nymph consequently. It was suggested that Diaphorina citri could be well controlled by spraying 0.5%-1% HMOs twice or more every other week in the peak occurrence at the area of Huanglongbing disease.

Figures and Tables | References | Related Articles | Metrics

Pathogen identification and indoor toxicity tests on root rot of Codonopsis pilosula

XU Xuefen, NI Chunhui, LI Huixia, LI Huanyu, LI Wenhao, CHEN Yuan, HU Fangdi

2021, 33(1): 96-103. DOI: 10.3969/j.issn.1004-1524.2021.01.12

Abstract ( 845 )

HTML ( 148 )

PDF (4182KB) ( 1927 )

In order to identify the pathogenic fungi causing the root rot of Codonopsis pilosula in Weiyuan County of Gansu Province and screen the best fungicides to control the disease, the pathogen causing the root rot of Codonopsis pilosula was isolated and purified by tissue isolation and single spore isolation. The pathogen was identified by pathogenicity determination, colony morphological characteristics, and clustering analysis of coding transcription extension factor region (TEF-1α). The toxicity was determined by growth rate method. The results of pathogen identification showed that Fusarium solani and Fusarium acuminatum were the pathogens causing root rot of Codonopsis pilosula in Weiyuan County of Gansu Province. The results of virulence test showed that all the six fungicides had inhibitory effect on them. Among them, 25% myclobutanil EC and 50% carbendazim WP had strong control effect (EC₅₀<0.05 g·L ^-1), which could be used as the main fungicides to control the root rot of Codonopsis pilosula.

Figures and Tables | References | Related Articles | Metrics

Prokaryotic expression of Plantago asiatica mosaic virus capsid protein and preparation of its polyclonal antibody

SU Xuesi, ZHANG Yubao, WANG Ruoyu, WANG Yajun, TANG Guoliang, JIN Weijie

2021, 33(1): 104-111. DOI: 10.3969/j.issn.1004-1524.2021.01.13

Abstract ( 1617 )

HTML ( 151 )

PDF (5967KB) ( 1966 )

The cp gene of Plantago asiatica mosaic virus (PlAMV) was cloned from an isolate of PlAMV, obtained from lily growing in Gansu Province, China. The cp gene fragment of 621 bp was constructed into the prokaryotic expression vector pET-28a (+), and the recombinant plasmid was transformed into Escherichia coli BL21 (DE3) to express the fusion CP protein. After IPTG induction and Ni-NTA gravity column chromatography, purified CP fusion protein was obtained and used as immunogen to prepare a rabbit-derived anti-CP polyclonal antibody. BLAST result showed that the similarity of nucleotide and amino acid sequences of cp gene was up to 74.7%-100% and 83.6%-100% between the cloned PlAMV isolate and the known PlAMV isolates, respectively. We noted that cp sequences from different hosts were significantly different, which suggested the distribution of PlAMV population was influenced by species of host. SDS-PAGE indicated that CP protein was highly expressed in E. coli BL21 (DE3), and had a relative protein molecular weight of 24 ku. Western blot result demonstrated that the prepared polyclonal antibody could successfully capture the natural PlAMV capsid proteins, which was used to check the expression level of PlAMV protein in susceptible plant tissue. This work provided a reference for the study of the pathogenic mechanism of PlAMV and the development of serological detection techniques for the virus.

Figures and Tables | References | Related Articles | Metrics

Structural characteristics of soil mite communities under different modes of rose-based agroforestry in Karst area

YANG Yiwei, XIAO Hua, CHEN Hu, XIAO Niejia, GUO Cheng

2021, 33(1): 112-121. DOI: 10.3969/j.issn.1004-1524.2021.01.14

Abstract ( 1075 )

HTML ( 164 )

PDF (942KB) ( 1948 )

As one of the intensive land use and management methods, agroforestry is beneficial to the restoration of soil biodiversity in rocky desertification areas. In July 2019, a total of 1 524 soil mites belonging to 3 orders, 41 families, 64 genera were captured from three kinds of agroforestry modes, namely, rose (Rosa rugosa Thunb)+soybean [Glycin max (Linn) Merr], rose+apple (Malus pumila Mill)+soybean, rose+corn (Zea mays Linn), with single cropping of rose mode as the control, in Longchang Village, Salaxi Town, Bijie City, Guizhou Province. The results showed that Tectocepheus and Parholaspulus were the dominant genus of soil mites in this area. Among all the four modes, rose+corn had a richer quantity of mite genera, while rose had a higher individual quantity. Soil mites were manifested as surface aggregation under four models. Rose+soybean and rose+corn had a higher diversity index and richness index. The similarity of soil mite communities among four models was relatively low, which belonged to medium unsimilarity. Predatory mites (Gamasina) were r-selected under three agroforestry modes, while it was K-selected under single cropping of rose mode. The structure of Oribatid mite community was P type under rose mode, and was O type under rose+soybean mode, and was G type under the other modes. In general, the implementation of rose-based agroforestry management increased the quantity and diversity of soil mites. Rose-based agroforestry with apple, soybean or corn was beneficial for the improvement of soil mite diversity, and the rose+soybean mode was more effective.

Figures and Tables | References | Related Articles | Metrics

Effect of different controlled-release fertilizers with urea ammonium on yield, nitrogen use efficiency and soil nutrients of rice

CHEN Gui, LU Chenni, SHI Yanping, NI Xiongwei, CHENG Wangda, ZHANG Hongmei, WANG Baojun, ZHANG Liping, SUN Da

2021, 33(1): 122-130. DOI: 10.3969/j.issn.1004-1524.2021.01.15

Abstract ( 876 )

HTML ( 682 )

PDF (921KB) ( 2037 )

In the present study, a field experiment was conducted to study the effect of different controlled-release fertilizers (CRFs) with urea ammonium (AU) on the yield, nitrogen use efficiency (NUE) and soil nutrients. The conventional fertilization method (N 225 kg·hm^-2) was introduced as CK, and three CRFs, namely, lignin-based CRF Haolegeng (HL), urea formaldehyde-based CRF Yongxiao (YX), and nitrification inhibitor-based CRF Kaileilou (KL), were selected to form three CRF+AU modes (HL+AU, YX+AU, and KL+AU), and the N input in these modes was reduced by 0, 20%, 35% and 50% as compared with CK, respectively. It was shown that there was no significant difference in yield within the treatments of CRF+AU modes with 20% N reduction and CK. However, when N reduction rate was 35% and 50%, the yields of rice under CRF+AU modes decreased significantly (P<0.05), which could be attributed to greater ratio of decreases in panicles per unit area and grains per panicle compared to seed-setting rate and 1 000-grain weight. The NUE increased with the reduction of N input under CRF+AU modes. When N reduction rate was 50%, NUE was the highest (20.1 kg·kg^-1) under KL+AU modes, and its grain physiological N-use efficiency (PE-grain) was significantly (P<0.05) increased by 14.7% than CK. When N reduction rate was 20% under YX+AU modes, the nitrogen uptake efficiency (NupE) and apparent N recovery efficiency (ANR) were significantly (P<0.05) increased by 12.4% and 22.3%, respectively, as compared with CK. Under CRF+AU modes, with the higher N reduction rate, the contents of soil alkali hydrolyzable N showed decreasing trends. However, the content of soil alkali hydrolyzable N was significantly (P<0.05) increased by 7.44%-9.57% than CK under CRR+AU modes without N reduction. Compared with CK, the soil pH under KL+AU was significantly (P<0.05) reduced by 0.17-0.31 pH unit. Based on the results of grain yield, NUE, ANR and soil nutrients, it was more reasonable to reduce N by 20% than CK under CRF+AU modes, and YX+AU had the best effect among them.

Figures and Tables | References | Related Articles | Metrics

Isolation and identification of an erythromycin degradation bacterium strain and its biodegradation characteristics

XU Shuangyan, ZHANG Tao, ZHANG Cheng, LIN Hui, SHUI Xianlei, ZHENG Huabao

2021, 33(1): 131-141. DOI: 10.3969/j.issn.1004-1524.2021.01.16

Abstract ( 1167 )

HTML ( 137 )

PDF (1676KB) ( 1883 )

In order to obtain efficient erythromycin degradation bacteria, erythromycin was used as the sole carbon source, and gradient domestication method was used to isolate and screen erythromycin degradation bacteria. It was shown that an erythromycin degradation bacterium strain Ery-6 was isolated from the soil of an organic fertilizer production workshop where chicken manure was stacked for a long time. The Ery-6 strain was identified as Methylobacillus sp. through colony morphology identification and 16S rDNA sequence analysis. Further, high performance liquid chromatography (HPLC) was used to measure the degradation rate of erythromycin, and the degradation conditions of erythromycin by Ery-6 strain were optimized, including different erythromycin concentration, culture temperature, rotation speed, initial pH value, exogenous carbon and nitrogen sources and metal ions. The Ery-6 strain could reach a degradation rate of 88.68% after 48 h in inorganic salt medium containing 100 mg·L^-1 erythromycin under temperature of 35 ℃, rotation speed of 120 r·min^-1, initial pH value of 7.0, and 50 mg·L^-1 sucrose. Meanwhile, the Ery-6 strain could tolerate 1 000 mg·L^-1 high-concentration erythromycin, and exhibited a degradation rate of 31.95% after 48 h under temperature of 35 ℃, rotation speed of 120 r·min^-1, initial pH value of 7.0. The Ery-6 strain had a good tolerance to various metal ions. Cu²⁺ could inhibit its growth, and pose direct effect on the degradation of erythromycin by Ery-6. The present study for the first time reported that the Methylobacillus sp. strain had the ability to degrade erythromycin, and it could tolerate high concentration of erythromycin, and maintain a certain degradation rate, which provided new microorganism for biodegradation of erythromycin in the environment.

Figures and Tables | References | Related Articles | Metrics

Comparison of quality of Hawk tea (Litsea coreana var. sinensis) in four counties of Guizhou Province

WANG Yuxin, DENG Yanli, YAO Songlin, WANG Ying, WANG Jihong

2021, 33(1): 142-149. DOI: 10.3969/j.issn.1004-1524.2021.01.17

Abstract ( 961 )

HTML ( 135 )

PDF (777KB) ( 1979 )

In order to compare the physical and chemical quality of Hawk tea (Litsea coreana var. sinensis) in four counties of Guizhou Province, the biochemical compositions and mineral elements of the Hawk tea processed in four counties of Guizhou Province were determined according to the traditional iron pot and slow fire drying process. The results showed that the content of biochemical compositions of Jiangkou Hawk tea was higher, especially the highest content of total flavonoid and the better quality; However, its heavy metal lead content exceeded the standard, which did not meet the requirements. Content of biochemical compositions of Xifeng sample was also high with the highest content of tea polyphenol and water extract,and the total flavone content was next to Jiangkou sample. The content of trace elements zinc, magnesium and selenium were also high and the content of heavy metals met the national standards with good quality, too. Moreover, Jiangkou Hawk tea had the most kinds of amino acid components; Meitan sample had the least kind of amino acid components; Chishui sample had a high content of trace metal elements and contained caffeine, and had a high content of amino acid with fresh taste, which was specific. The four Hawk tea in different counties in Guizhou Province had different characteristics in physical and chemical quality.

Figures and Tables | References | Related Articles | Metrics

Evaluation of high-quality agricultural development level in major grain producing areas in China and its spatial and temporal evolution

ZHANG Faming, DING Feng, WANG Ping

2021, 33(1): 150-160. DOI: 10.3969/j.issn.1004-1524.2021.01.18

Abstract ( 870 )

HTML ( 244 )

PDF (1054KB) ( 2009 )

In order to explore the reality of China’s high-quality agricultural development, and realize rural revitalization, agriculture and rural modernization, an evaluartion index system for the development level of high-quality agriculture in China’s major grain-producing areas was established based on the concept of high-quality development and five development concepts. The entropy weight TOPSIS method was used to comprehensively evaluate the agricultural high-quality development level in major grain-producing areas. After that the spatial-temporal evolution characteristics were discussed. The results showed that the level of high-quality agricultural development in main grain-producing areas in China was low and the trend of fluctuation was rising. Meanwhile, Jiangsu had maintained its first position for a long time. The number of medium-high level areas in China’s main grain-producing areas showed an obvious increasing trend. The medium-high level areas expanded from China’s coastal areas to the central region, such as Hubei, Hunan and Jiangxi. The positive agglomeration trend of high-quality agricultural development in major grain-producing areas had continued to increase. Most of the main grain-producing areas had weak connection with each other, showing a trend of isolated development. Hot spots for high-quality agricultural development were shrinking and then expanding. Hot spots had evolved and strengthened from north to south, from the eastern coastal region to the central region. Therefore, it was necessary to adjust the structure of agricultural industry, increase input in agricultural technology, promote regional cooperation in agriculture, and realize green development of agriculture in order to improve the level of high-quality agricultural development in China.

Figures and Tables | References | Related Articles | Metrics

Various forms of moderate-scale management of agriculture and development prospects

LI Haitao, FU Linlin, HUANG Zuhui, PENG Wenhuan

2021, 33(1): 161-169. DOI: 10.3969/j.issn.1004-1524.2021.01.19

Abstract ( 981 )

HTML ( 175 )

PDF (1063KB) ( 1882 )

It has become a consensus at the theoretical and policy level that moderate-scale management is an important way to improve agricultural benefits and enhance farmers’ income. In the present assay, the evolution of relevant policies was reviewed, and three types of practice and innovation in this field, namely the moderate-scale management of land, services, and multi-functionality, were analyzed by taking Zhejiang Province as an example. In light of problems like the dominance of small-scale operation, underdeveloped socialization services, and inadequate benefits of moderate-scale management, corresponding suggestions were put forward, including strengthening land rights to consolidate the foundation of moderate-scale management, exploring diversified socialization services to improve their scale merits, perfecting laws, regulations and policies to better safeguard moderate-scale management, and cultivating new entities to improve the quality of entities of scale management.

Figures and Tables | References | Related Articles | Metrics

Spatial-temporal characteristics and coordination of agricultural high-quality development in China

DONG Yanmin, YAN Fengxian

2021, 33(1): 170-182. DOI: 10.3969/j.issn.1004-1524.2021.01.20

Abstract ( 829 )

HTML ( 7442 )

PDF (1199KB) ( 2024 )

From the 5 elements of production efficiency, industry benefits, green production, quality of labors, and the farmers’income, 14 indexes were selected to construct the evaluation system of agricultural high-quality development, and the level, spatial correlation and coordination degree among elements of agricultural high-quality development in 2000-2018 in China (Hongkong, Macau and Taiwan not included) were analyzed by entropy method, Moran index, and coordination degree method. The results showed as follows: (1) From 2000 to 2018, the agricultural high-quality development level in China has gradually increased from 0.355 39 in 2000 to 0.482 40 in 2018, with an average annual growth rate of 1.71%. (2) There are large regional differences in the agricultural high-quality development level in China, and it has the characteristics of clustering. From the western region to the eastern coast, the agricultural high-quality development level has gradually increased. The agricultural high-quality development level in the adjacent provincial administrative regions affects mutually, and present the state of “the same high and the same low”. (3) The coordination degree among elements of agricultural high-quality development in China has improved from 2000 to 2018, but it still needs to be strengthened. (4) China’s agricultural high-quality development level is consistent with the coordination dgeree among elements of agricultural high-quality development. In other words, the regions with high level of agricultural high-quality development, also have relatively high coordination degree among elements of agricultural high-quality development.

Figures and Tables | References | Related Articles | Metrics

Archive