Current issue

• 2021 Vol.37 No.23 Published:15 August 2021

  The Direct Seeding Characteristics of Rice from Russia Lin Cuixiang, Song Longfei, Sergey Garkusha, Song Fengshun, Zhanna Mukhina, Teng Bin, Gan Quan, Vitor Kovalyov, Yu Haibing, Lubov Yesaulova, Ni Dahu 2021, 37 (23):  1-7.  DOI: 10.11924/j.issn.1000-6850.casb2020-0550 Abstract + ( 302 )   HTML ( 6 )   PDF ( 1466KB )   ( 42 ) In order to obtain germplasm resources with excellent direct seeding characteristics, 10 rice germplasms introduced from Russia were used to study the characteristics of mesocotyl elongation length, germination capacity at low temperature and germination ability under submerging. The results showed that the germination rate of ‘LIDER’, ‘ATLANT’, ‘OLIMP’ was the fastest, and ‘LIDER’, ‘OLIMP’, ‘ATLANT’, ‘NATASHA’, ‘ISTOK’ and ‘PARTNER’ had better germination ability under low temperature condition. The mesocotyl elongation length of ‘ATLANT’, ‘ISTOK’, ‘RAPANZ’, ‘GAMMA’, ‘OLIMP’ and ‘SONET’ was significantly different from ‘Luxianggen 28’ at 5% level. Under anoxic condition, there were significant differences of germination ability under submerging among all varieties. All varieties introduced from Russia exhibited better germination rate than the control. Among the 10 Russian varieties, ‘ATLANT’ had the best comprehensive traits related to direct seeding. The mesocotyl elongation length, germination capacity at low temperature and germination ability under submerging of ‘ATLANT’ were significantly better than the control.

  Comprehensive Evaluation of Maize Varieties in Southern Shandong Province by DTOPSIS Method Based on Entropy Weight Zhang Chunyan, Wu Ronghua, Zhuang Kezhang, Xu Jie, Li Xinxin, Li Jing, Wang Heng, Qi Xiaofeng 2021, 37 (23):  8-14.  DOI: 10.11924/j.issn.1000-6850.casb2020-0401 Abstract + ( 223 )   HTML ( 5 )   PDF ( 1328KB )   ( 47 ) In order to screen maize varieties suitable for planting in southern Shandong Province and explore a new comprehensive evaluation method of maize varieties, DTOPSIS method based on entropy weighting was used to analyze the biological characters of 23 maize varieties, such as ear length, ear diameter, bald tip length, ear row number, grain number per row, 100 grain weight, etc., as well as seed production rate and yield. The results showed that ‘Jundan20’ (Ci=0.99745), ‘Liangyu99’ (Ci =0.47061), ‘Zhengdan958’ (Ci=0.47059), and ‘Jinboshi509’ (Ci=0.47059). ‘Xianyu 047’ (Ci=0.29413) has excellent comprehensive characters and is recommended to be the preferred maize variety in southern Shandong.

  Expression Amount of cry2A* Gene at Different Growth and Development Stages of Transgenic Pest-resistant Rice ‘HD2’ Li Rongtian, Yu Xiaochen, Kong Mengying, Liu Changhua 2021, 37 (23):  15-22.  DOI: 10.11924/j.issn.1000-6850.casb2021-0070 Abstract + ( 359 )   HTML ( 6 )   PDF ( 1520KB )   ( 42 ) The purpose is to investigate the expressing amount of cry2A* gene and brown rice Bt protein content (BPC) in transgenic cry2A* Gene Resistant Rice ‘HD2-1’ and other independent lines during the growth and development stages. qRT-PCR and enzyme-linked immunosorbent assay (ELISA) were used to detect the expression amount of cry2A*gene of organs at different growth and development stages and brown rice BPC. The results showed that there was a significant difference among rice independent lines in expression amount of cry2A* gene and BPC of brown rice. There were often positive correlation of the expression amount of cry2A* gene of leaf blade, sheath-culm and young panicle among different growth and development stages. The mRNA expression of cry2A* gene was positively correlated with the corresponding BPC. And there was a positive correlation trend between BPC of brown rice and expression amount of cry2A* gene of each organ at each stage. In expression amount of cry2A* gene of rice‘HD2’, there were positive relations among different growth and development stages and between the ones and BPC of brown rice. The higher the cry2A* gene transcribed, the higher the BPC was.

  CM8101 Transgenic Maize: Qualitative PCR Assay Detection of Specificity Long Likun, Zhao Ning, Xia Wei, Li Congcong, Dong Liming, Yan Wei, Li Feiwu 2021, 37 (23):  23-28.  DOI: 10.11924/j.issn.1000-6850.casb2020-0576 Abstract + ( 471 )   HTML ( 8 )   PDF ( 1495KB )   ( 59 ) To provide technical support for GM (genetically modified) safety supervision, a qualitative detection method for GM maize CM8101 was established. According to the insertion sequence information of CM8101, PCR primers were designed in the 3' end flanking sequence. Through the amplification system optimization, the specificity test, sensitivity and stability tests, a specific method of CM8101 was developed. The results showed that all test parameters of this method met the requirements of transgenic molecular detection standard. The method had good specificity, and the detection sensitivity reached 0.1%. CM8101 is a new transgenic maize line with industrial application prospect independently developed in China, so this method can provide a technical means for the identification of CM8101 and its derives.

  Lactic Dehydrogenase Gene Deletion Mutant of Enterobacter cloacae: Construction and Biological Characteristics Shi Huiling, Zhou Yuhang, He Ping, Huang Mengmeng, Shao Shuai, Ge Jingping, Ling Hongzhi 2021, 37 (23):  29-37.  DOI: 10.11924/j.issn.1000-6850.casb2020-0837 Abstract + ( 450 )   HTML ( 5 )   PDF ( 2033KB )   ( 46 ) The aims are to construct a lactic dehydrogenase mutant of Enterobacter cloacae by suicide plasmid recombination technique, and lay a foundation for further increasing acetoin yield and expanding the range of strain selection. The homologous fragment was inserted into the suicide plasmid pKR6K by double restriction endonuclease digestion, and the ldh gene knockout plasmid was constructed. Then the ldh gene of E.cloacae was knocked out by bacterial conjugation. Two homologous sequences of E.cloacae lactate dehydrogenase gene were successfully cloned with a length of 526 bp. Sequence alignment analysis showed that the sequence similarity of E.cloacae lactate dehydrogenase gene was 100%. By knocking out the lactate dehydrogenase gene of E.cloacae, a ldh deletion recombinant strain E.cloacae△ldh, was successfully constructed, while 2,3-butanediol and acetic acid were increased by 6.8% and 24.3%, respectively. The E.cloacae lactic dehydrogenase deletion engineering strain was successfully created, which lays a foundation for the industrial production of acetoin by the microbial method.

  Antibacterial and Anti-anthracnose Activities of Endophytic Fungi Colonized in Blumea balsamifera (L.) DC. Yuan Chao, Shu Xuechun, Zhang Yingbo, Wang Kai, Xie Xiaoli, Xu Ziqi, Yuan Yuan 2021, 37 (23):  38-44.  DOI: 10.11924/j.issn.1000-6850.casb2020-0501 Abstract + ( 258 )   HTML ( 6 )   PDF ( 1871KB )   ( 38 ) To obtain abundant endophytic fungi from Blumea balsamifera (L.) DC., and select bio-control strains for discovery of bioactive metabolites, water-agar method was used to isolate endophytic fungi from Blumea balsamifera (L.) DC distributed in Hainan Island. ITS analysis was adopted for identification and analysis of endophytic fungi. Furthermore, the activities of fermented endophytes culture extract against four strains of bacteria were tested by filtering paper method. Plate confrontation was carried out to evaluate the inhibitory effects of endophytes on four strains of anthracnose. As a result, 191 strains were isolated and identified, which belonged to 27 genuses, 45 species, the dominant genuses included Diaporthe, Paraphoma, Ectophoma, Penicillium, Talaromyces, Hypoxylon, Phomopsis, Colletotrichum and Fusarium. Clonostachys, Fusarium and Diapothe were more active in antibacterial assay. Anti-anthracnose results showed that the endophyts belonged to Talaromyces, Ectophoma and Penicillium toughly inhibited four strains of anthracnose. In conclusion, our research preliminary discussed the category variety of endophytic fungi derived from Blumea balsamifera collected in Hainan Island, bioactivity-guided screening was carried out firstly, and the selected active endophytic fungi may serve as candidates for founding new agronomic agents.

  Effects of Microbial Fertilizer on Growth and Quality of Flue-cured Tobacco ‘K326’ Liang Yongjin, Shang Haili, Pan Wenzheng, Zhao Xuetong, Li Dewen, Li Jianyun, Zhang Qi 2021, 37 (23):  45-51.  DOI: 10.11924/j.issn.1000-6850.casb2020-0661 Abstract + ( 371 )   HTML ( 4 )   PDF ( 1230KB )   ( 48 ) To screen the microbial fertilizer suitable for the ecological environment of Hechi tobacco area, and to study the effects of different types and application methods of microbial fertilizer on the growth and development of flue-cured tobacco and the yield and quality of tobacco leaves, a microbial fertilizer exploration experiment was conducted in Nandan County, Hechi City, taking main tobacco variety ‘K326’ as the test object. The results show that: the application of microbial fertilizer at the time of transplanting and 10 days after transplanting could significantly improve the yield and quality of tobacco, effectively promote the growth and development of tobacco, and significantly increase the plant height, stem circumference, effective leaf number, leaf length and leaf width compared with the control. The microbial fertilizer could improve the yield and output value of tobacco, significantly improve the physical properties, chemical composition indexes and appearance quality of flue-cured tobacco leaves, increase the potassium oxide content of each part of tobacco leaves and the nicotine content of upper leaves, and make the chemical components in tobacco leaves more coordinated. Three kinds of microbial fertilizers have the best effect on the tobacco production in the Hechi tobacco area by root irrigation at the time of transplanting and 10 days after transplanting.

  Effects of N, P, K Dosage and Distribution of Basic and Topdressing Nutrients on Yield and Quality of Tobacco Leaves Yu Yaoying, Wang Mingfu, He Jixian, Zhang Qili, Chen Liping, Jiang Hao, Gu Huizhan 2021, 37 (23):  52-60.  DOI: 10.11924/j.issn.1000-6850.casb2020-0654 Abstract + ( 384 )   HTML ( 4 )   PDF ( 1331KB )   ( 30 ) To improve the quality of tobacco leaves and clarify a nutritionally balanced fertilization system in flue-cured tobacco on lime purple soil, in 2018-2019, a field orthogonal experiment was carried out to study the effects of different dosage of NPK and the different proportion of NK on the agronomic characters, yield and chemical index of the tobacco. The results showed that: (1) NPK application rate had significant effect on agronomic traits of flue-cured tobacco, N had significant effect on SPAD and chemical composition, N and P had significant effect on yield, and the yield was positively correlated with N application rate; (2) N2P3K2 (97.5, 150 and 315 kg/hm2) was the best fertilization combination for Guangyuan flue-cured tobacco; (3) the application of nitrogen fertilizer forward and potassium fertilizer backward was more conducive to improving the internal quality of tobacco leaves. Balanced fertilization system of flue-cured tobacco cultivation in Guangyuan is NPK application rate of 97.5, 150 and 315 kg/hm2, respectively, and the nutrient allocation ratio of NK base fertilizer and top dressing fertilizer is N base: topdressing = 7:3, K base: topdressing = 3:7.

  Spatial Variability Characteristics and Influencing Factors of Soil Nutrients in Farmland in Typical Hilly and Plain Area of Southeast Shandong Duan Youchun 2021, 37 (23):  61-68.  DOI: 10.11924/j.issn.1000-6850.casb2020-0853 Abstract + ( 257 )   HTML ( 6 )   PDF ( 1848KB )   ( 43 ) In this research, a town was chosen as a case in the hilly and plain area of southeast Shandong Province. The spatial variable characteristics of organic matter (SOM), total nitrogen (TN), alkali-hydro-nitrogen (AN), available phosphorus (AP) and available potassium (AK) in soil and their influencing factors were studied by geostatistics method based on the data collected from 200 farmland surface soil samples. The results show that the average content of SOM, TN, AN, AP and AK are 13.52 g/kg, 0.75 g/kg, 87.27 mg/kg, 50.55 mg/kg and 103.20 mg/kg, respectively. The soil nutrient content as a whole is slightly deficient. The variable coefficient of the 5 kinds of soil nutrients is ranked as AP>AN>AK>TN>SOM in order of size, all with moderate degree of variation. Statistical analysis shows that the variation function of the 5 kinds of soil nutrients accords with exponential model. The spatial distribution of soil nutrient content grade was mapped through the ordinary Kriging spatial interpolation method. Overall, the level of soil organic matter and total nitrogen content in the study area are low. In terms of the content level and distribution range, other effective components are slightly better. Topographic and geomorphic factors, soil types, land use patterns and other factors have a significant influence on the spatial variation degree of soil nutrients in the study area, among which, structural factors such as topographic and geomorphic factors and soil types have a strong influence.

  Effects of Potassium Fertilizer Application Rate on Lodging Resistance and Yield of Oil Flax Varieties in Dry Land Li Zhengsheng, Ma Lijuan, Dong Hongwei, Gao Yuhong, Yan Bin, Cui Zhengjun, Wang Yifan, Wu Bing 2021, 37 (23):  69-76.  DOI: 10.11924/j.issn.1000-6850.casb2020-0597 Abstract + ( 310 )   HTML ( 7 )   PDF ( 1394KB )   ( 40 ) To explore the mechanism of potassium fertilizer regulating the lodging resistance of oil flax, in field environment, two local oil flax varieties ‘Longya 11’ (V1) and ‘Dingya 23’ (V2) were used as test materials, and the split plot experiment was conducted with four potassium application levels: no potassium (K0, 0 kg/hm 2), low potassium (K1, 30 kg/hm2), medium potassium (K2, 60 kg/hm2) and high potassium (K3, 90 kg/hm2). The effects of different varieties and potassium fertilizer combinations on the plant height, center of gravity height, stem diameter, flexural resistance, lodging resistance index, actual lodging rate, yield and yield components of dry land oil flax and their relationship with plant lodging resistance characteristics were analyzed. The results showed that, the potassium fertilizer application rate of 0~90 kg/hm2 could not only promote the growth and development of oil flax, but also improve its lodging resistance, and ultimately increase its yield. After potassium application, the plant height and center of gravity height of the two varieties of oil flax were increased by 4.74% and 8.88% respectively during the whole growth period compared with no potassium application (K0). The stem diameter (green fruit stage) was the largest when the potassium application rate was 60 kg/hm2 (K2), increased by 11.79% on average compared with no potassium (K0). The flexural resistance and lodging resistance index of oil flax stalks after applying potassium were 18.32% and 11.50% higher than those without potassium (K0). The actual lodging rate of oil flax under different potassium application levels was: K2<K3<K1<K0, while the yield performance was: K2>K3>K1>K0, and the yield increase rate were 20.69%, 24.93%, and 17.15%, respectively. Correlation analysis showed that the plant height of oil flax and center of gravity height had no significant correlation with the stalk bending resistance, but had a significant and an extremely significant negative correlation with the lodging resistance index (except for the mature period); the flexural resistance and lodging resistance index of oil flax stalks in each growth period were positively correlated with stem diameter, and had a significant and an extremely significant positive correlation with grain yield. In general, under the experimental condition of the study, 60 kg/hm2 is the appropriate potassium fertilizer application rate, which could not only increase the yield, but also effectively enhance the lodging resistance of oil flax.

  Cadmium of Buckwheat in Farmland: Accumulation and Transport Characteristics with Different Cadmium Background Values Zhang Lu, He Luqiu, Yang Xuele 2021, 37 (23):  77-83.  DOI: 10.11924/j.issn.1000-6850.casb2020-0470 Abstract + ( 281 )   HTML ( 5 )   PDF ( 1336KB )   ( 44 ) The aims are to clarify the cadmium accumulation and transport characteristics of buckwheat in farmland with different cadmium background values, and lay the foundation for the phytoremediation of cadmium contaminated farmland. Using 8 buckwheat varieties (lines) as materials, multi-point experiments were carried out in 9 cadmium-contaminated farmlands to detect cadmium contents in buckwheat roots, stems and leaves, and grains. The results showed that buckwheat had a strong ability to absorb and accumulate cadmium. Within a certain range, as the soil cadmium content increased, the cadmium content of buckwheat grains first showed an increasing trend, and then the cadmium content no longer increased significantly. The absorption law of cadmium in different parts of buckwheat at maturity stage was as following: stems and leaves>roots>grains. The cadmium enrichment coefficient of stems and leaves was 2.03-5.52, the cadmium enrichment coefficient of roots was 1.03-4.08, and the cadmium enrichment coefficient of grains was 0.15-0.92. The cadmium transport coefficient of roots-stems and leaves was 1.34-2.30, and the cadmium transport coefficient of stems and leaves-grains was 0.07-0.22. The results indicate that buckwheat has obvious cadmium accumulation capacity and strong cadmium transport capacity, and could be used as a potential plant for remediation of heavy metal contaminated soil, and soil cadmium is mainly transported and accumulated in stems and leaves.

  The Formation of Land Dividends Based on Different Classification Criteria Ling Jiahui, Liu Hongmei 2021, 37 (23):  84-88.  DOI: 10.11924/j.issn.1000-6850.casb2020-0800 Abstract + ( 323 )   HTML ( 4 )   PDF ( 1170KB )   ( 28 ) The purpose of the paper is to redefining the concept of land dividends, classifying land dividends, and exploring the formation of land dividends which based on different classification criteria. The research methods included comprehensive analysis and generalization. The results show that: the formation of land dividend not only comes from the process of land use change, but also comes from the improvement of land use efficiency. The formation of land dividend is closely related to the change of land use, property right, space and intensity. The change of land use and land ownership would form a certain amount of land dividend. It is necessary to use advanced technology to increase land intensively and efficiency, promote the formation of land dividends from changing the land use to improving the efficiency of land use.

  Effects of Reducing Irrigation and Chemical Fertilizers on Forms and Distribution of Inorganic Phosphorus in Facility Vegetable Field of Black Soil Guan Shiyang, Wang Jiaqi, Yu He, Jiao Xiaoguang, Wang Yao, Xu Xin, Chen Yimin, Sui Yueyu 2021, 37 (23):  89-93.  DOI: 10.11924/j.issn.1000-6850.casb2021-0106 Abstract + ( 234 )   HTML ( 4 )   PDF ( 1226KB )   ( 30 ) In this study, facility vegetable field of black soil in northeast China was taken as the research object, and three treatments of regular chemical fertilizers + regular irrigation (WF), regular irrigation + 80% chemical fertilizers (W80%F) and 80% regular irrigation + regular fertilizers (80%WF) were set to study the effect of reducing irrigation and chemical fertilizers on inorganic phosphorous and its availability in facility vegetable field. The results showed that: compared with the regular irrigation and chemical fertilizers treatment, the content of soil available phosphorus increased slightly after 4 years of reducing irrigation and chemical fertilizers treatment, and the content of soil available phosphorus in reducing irrigation treatment was higher than that in reducing chemical fertilizers treatment. With the increase of soil depth, the contents of soil available phosphorus decreased gradually in the same treatment. The order of inorganic phosphorus content from high to low was: Ca8-P > O-P > Fe-P > Ca10-P > Ca2-P > Al-P, and it gradually decreased with the increasing soil depth. Ca8-P and Al-P accounted for the largest proportion. Correlation analysis showed that: Ca2-P, Ca8-P, Al-P, Ca10-P and Fe-P had significant positive correlation with the content of available phosphorus, the correlation coefficient of each form of inorganic phosphorus and available phosphorus content was Ca2-P>Al-P>Ca8-P>Ca10-P>Fe-P>O-P.

  Water Level Change of Dongping Lake and Its Impact on Water Quality from 1990 to 2016 Li Jingxuan, Chen Yingying, Han Fei, Chen Shiyue 2021, 37 (23):  94-100.  DOI: 10.11924/j.issn.1000-6850.casb2020-0812 Abstract + ( 272 )   HTML ( 7 )   PDF ( 1265KB )   ( 46 ) Based on the measured hydrological data of water level and water quality of Dongping Lake during 1990—2016 from hydrological stations, Spearman rank correlation coefficient was used to analyze the annual variation characteristics of the water level and the main indexes of water quality, and the correlations between the water level and the water quality were discussed. The potential water quality changes of Dongping Lake after the implementation of the Eastern Route of the South-to-North Water Diversion Project were explored as well. The results showed that: the annual water level of Dongping Lake presented a fluctuating upward trend from 1990 to 2016. The water level had a significantly negative correlation with TP and CODMn, with the correlation coefficient of -0.685 and -0.550, respectively; the water level was negatively correlated with the COD, with a weak correlation coefficient of -0.389; TN was mainly controlled by the pollution from Dawen River. To a certain extent, the Eastern Route of the South-to-North Water Diversion Project has improved the water quality of Dongping Lake, but the water environment problem has not been solved. To meet the water quality requirements of the South-to-North Water Diversion Project and support the sustainable development of Dongping Lake ecosystem and even the lower reaches of the Yellow River, it is suggested that the water quality of Dongping Lake should be managed by adjusting the water level and reducing the intensity of human activities.

  Peanut Net Spot Disease: Selection of Chemical Control Agents and Compound Synergistic Formulas Xie Jinhui, Lin Ying, Zang Chaoqun, Pei Xue, Liang Chunhao 2021, 37 (23):  101-105.  DOI: 10.11924/j.issn.1000-6850.casb2020-0633 Abstract + ( 348 )   HTML ( 7 )   PDF ( 1197KB )   ( 34 ) In order to screen effective fungicides for preventing and controlling peanut net spot pathogen, mycelial growth rate method was used to determine the indoor virulence activity of 12 kinds of fungicides against the pathogen of peanut net spot to screen out fungicides with good control efficacy. Different types of fungicides were selected and compounded to determine the indoor virulence activity against peanut net spot pathogen. The results showed that: 95% fludioxonil, 98.6% azoxystrobin, 97% prochloraz, 95% difenoconazole, 95% hexaconazole, 95% thiophanate methyl and 97% tebuconazole all had a strong inhibitory effect on peanut net spot. When 87% polyram and 97% prochloraz were compounded at a ratio of 1 to 9, it had a synergistic effect with an EC50 value of 0.673 μg/mL. The results of the indoor virulence test showed that both the selected single fungicides and compounded fungicides had inhibitory effects on mycelial growth of peanut net spot. This study could provide a theoretical basis for the research of peanut net spot disease, and also lay a foundation for the next field control experiment.

  Application and Research Progress of Immunoassay Technology in Rapid Detection of Pesticide Residues Guo Siyi, Sun Mingna, Dong Xu, Chu Yue, Tong Zhou, Wang Mei, Gao Tongchun, Duan Jinsheng 2021, 37 (23):  106-112.  DOI: 10.11924/j.issn.1000-6850.casb2020-0419 Abstract + ( 232 )   HTML ( 6 )   PDF ( 1230KB )   ( 36 ) In order to solve the problems of time-consuming and high cost in the detection of pesticide residues by conventional methods such as chromatography, a simple, fast, high selectivity and high sensitivity rapid detection method for pesticide residues based on immunoassay was proposed. This review summarized the principles, characteristics and research progress of commonly used rapid detection techniques for pesticide residues, including enzyme-linked immunosorbent assay, fluorescence immunoassay, immunochromatography, immunomagnetic beads, biomimetic immunoassay and bio-barcode assay. Different methods have their own advantages, disadvantages and scope of application, and the rapid development of molecular imprinting, nanotechnology and genetic detection technology could provide high sensitivity and accuracy for pesticide residue immunoassay. Based on the advantages of immunoassay technology, it will play an important role in the field of rapid pesticide residue detection combined with new technology and continuous improvement. The miniaturization and integration of the detection methods, and higher stability and sensitivity of detect instruments are the development direction of pesticide residue detection in the future.

  Effects of Nano Selenium and Chitosan Compounds on Lettuce Planted in Cadmium-contaminated Soils Li Jianzhao, Gao Wanchao, Li Xian, Liu Pei, Jiang Bin, Tong Chunyi 2021, 37 (23):  113-117.  DOI: 10.11924/j.issn.1000-6850.casb2020-0830 Abstract + ( 207 )   HTML ( 4 )   PDF ( 1264KB )   ( 30 ) To obtain the safe production conditions of lettuce, the effects of nano selenium, chitosan and their combined fertilization on the yield, quality and cadmium content of lettuce planted in heavy metal contaminated soil were investigated. The results showed that compared with the control group, the application of nano selenium, chitosan and their combination could significantly improve the quality of lettuce, in which the fresh weight increased by 14.08%-53.73%, chlorophyll increased by 2.36%-22.38%, soluble reducing sugar content increased by 21.95%-407.66%, soluble protein content increased by 41.47%-112.73%, and Cd content decreased by 9.59%-19.49%. The combination of nano selenium and chitosan had obvious synergistic effect. When nano selenium was 30 mg/L and chitosan was 100 mg/L, the cadmium content in lettuce was the lowest, and the yield and quality were the best. The optimal ratio of nano selenium and chitosan is found in this study and the compatibility could be used for safe production of crops in soils with excessive heavy metals.

  Culter alburnus Basilewsky in Different Populations: Genetic Diversity Analysis Based on Cytochrome B (Cyt b) Gene Zhang Guining, Fang Di’an, Xue Xiangping, Zhang Minying, Feng Xiaoting, Yang Xuejun 2021, 37 (23):  118-124.  DOI: 10.11924/j.issn.1000-6850.casb2021-0127 Abstract + ( 181 )   HTML ( 5 )   PDF ( 1643KB )   ( 39 ) In order to understand the genetic diversity of different Culter alburnus Basilewsky populations in the lower reaches of the Changjiang River, and evaluate the resource status of C. alburnus. A total of 211 C. alburnus samples from Dianshan Lake (DSH), Taihu Lake (TH), Changdang Lake (CD) and Changjiang River (CJ) were studied. Mitochondrial DNA b gene (Cyt b) of C. alburnus was sequenced, and compared with NCBI. Genetic diversity data of four C. alburnus populations were analyzed by MEGA, DNASP and other software. The Cyt b gene sequence was 1088 bp in length, with 55% A+T and 45% G+C. A total of 258 polymorphic sites were detected, accounting for 23.71% of the total nucleotides. 46 haplotypes were found in 211 samples from 4 populations, and the haplotype diversity ranged from 0.849 to 0.946, the order was as following: TH>CD>CJ>DSH. The nucleotide diversity was 0.0083-0.174, which was represented as DSH> CD>CJ>DSH. The genetic distance between the four populations was 0.052-0.152, and the maximum was 0.152 between Taihu population and Dianshan Lake population. The genetic differentiation indices ranged from 0.197 to 0.646, and the gene flow values ranged from 0.152 to 1.019, among which the gene flow values of Changjiang River and Dianshan Lake populations were the smallest, while those of Changjiang River and Changdang Lake populations were the largest. The results of phylogenetic tree based on NJ method showed that there was no obvious geographical differentiation among the four populations. The results of this study indicated that the population genetic diversity of C. alburnus in the lower reaches of the Changjiang River was high. Combined with the results of fishery resources investigation in recent years, the genetic background and germplasm resources of C. alburnus in the lower reaches of the Changjiang were further understood, which provided basic data for wild resource conservation.

  Lettuce and Celery at Different Growth Stages: Comparison of Water Purification Capacity Gao Xiating, Song Hongqiao, Zhang Haigeng, Ni Qi, Zhang Yulei 2021, 37 (23):  125-132.  DOI: 10.11924/j.issn.1000-6850.casb2020-0651 Abstract + ( 482 )   HTML ( 4 )   PDF ( 1377KB )   ( 44 ) This study aims at selecting economical plant which not only has highly effective capacity for water purification but also is suitable for aquaponics, and laying foundation for improving the environmental purification capacity of aquaponics. The raft-floating aquaponics was constructed in this study. Tilapia, lettuce and celery in different sizes were selected as experimental materials, and the dynamic variation of water quality was investigated for 36 days. The long-term (36d) tests showed that the highest concentration of nitrogen pollutants in small celery system were lower than that in lettuce and big celery, and the stability of water quality in small celery system was achieved earlier than the other two. However, the trends of total phosphorus among the three economical plants were similar. The short-term (24h) static tests indicated that the removal rate of TAN, NO2-N and NO3-N were the highest in the small celery system, which was 39.85%, 26.33% and 61.11% respectively; and lower in lettuce, which was 30.79%, 17.15% and 35.90% respectively; and the lowest in big celery, which was 17.76%, 12.93% and 24.66% respectively. However, TP results showed that the phosphorus removal rate of lettuce (62.9%) is significantly higher than small celery (44.79%) and big celery (14.60%). It is concluded that among small celery, big celery and lettuce, small celery has the strongest capacity in nitrogen removal, and lettuce has the strongest capacity in phosphorus removal.

  Progress and Perspective on Research of Pseudogobio vaillanti Zhong Quanfu, Chen Bin, Fan Haiping, Lin Yu 2021, 37 (23):  133-137.  DOI: 10.11924/j.issn.1000-6850.casb2020-0382 Abstract + ( 399 )   HTML ( 6 )   PDF ( 1164KB )   ( 38 ) The aim of the paper is to provide a scientific basis for the protection and development of Pseudogobio vaillanti. With the help of published literature and materials provided by research and development institutes, the research status of taxonomy and geographic subdivision, morphological characters, living habit, reproductive characteristics, nutritive value, artificial domestication and propagation, resource protection, resource exploitation and utilization of Pseudogobio vaillanti are comprehensively introduced. At the same time, the application prospects of Pseudogobio vaillanti’s breeding development are discussed. Pseudogobio vaillanti is a potential variety for rural revitalization and targeted poverty alleviation in the mountainous areas because of its good market foundation and strong potential for fishery development and utilization. It is suggested that the breeding of the cultured varieties of Pseudogobio vaillanti and the research and development of complete formula feed should be accelerated, so as to provide a technical basis for its promotion.

  Remediation Technologies of Polycyclic Aromatic Hydrocarbons Contaminated Soil: A Review Teng Qing, Wang Chun, Lin Xuanjie, Xie Meibing, Cheng Lusi 2021, 37 (23):  138-143.  DOI: 10.11924/j.issn.1000-6850.casb2020-0813 Abstract + ( 261 )   HTML ( 4 )   PDF ( 1228KB )   ( 41 ) As a typical persistent organic pollutant in the environment, polycyclic aromatic hydrocarbons (PAHs) have attracted much attention because of their strong toxicity and great harm. The researches on main remediation technologies of soil PAHs pollution at home and abroad in recent years were summarized from the aspects of bioremediation, physical remediation and chemical remediation. Bioremediation technology has the advantages of low cost, convenient operation and small secondary pollution, but it has long remediation cycle and is not suitable for high concentration polluted soil. Physical remediation and chemical remediation can be used for high-concentration contaminated soil, but there are some disadvantages, such as changing the original structure of the soil and high operating and maintenance costs. For high-concentration PAHs contaminated soil, it is advisable to remove most of the pollutants by physical and chemical remediation first, and then use bioremediation for harmless treatment to realize the recycling of contaminated soil.

  Fertilizer Use Efficiency and Its Influencing Factors of Facility Vegetable Growers Hua Wenyuan, Li Ninghui, Luo Liangguo 2021, 37 (23):  144-150.  DOI: 10.11924/j.issn.1000-6850.casb2021-0417 Abstract + ( 216 )   HTML ( 3 )   PDF ( 1254KB )   ( 26 ) The rapid increase in the use of chemical fertilizer has not only reduced the efficiency of chemical fertilizer use, but also caused a series of environmental problems. Clarifying the fertilizer use efficiency and its influencing factors can help the government formulate relevant policies to guide farmers’ fertilizer use and reduce the agricultural non-point source pollution. Based on 113 survey data of facility vegetable growers in Liaoning and Shandong, the technical efficiency and fertilizer use efficiency of facility vegetable growers were measured by a stochastic frontier analysis model. Influencing factors of the fertilizer use efficiency was also investigated. The results show that the technical efficiency of most farmers in the survey area is between 60% and 70%, and the fertilizer use efficiency is between 10% and 30%. There is a significantly positive relationship between farmers’ participation in technical training and the fertilizer use efficiency and the participation in technical training could increase the efficiency by 8.6%. In addition, the fertilizer use efficiency is also closely related to farmers’ education level and whether they have environmental awareness. It is necessary to further strengthen the research and practice of applicable methods and technologies to improve the fertilizer use efficiency, and conduct technical training and promote the transmission of agricultural knowledge.

  Measure of Production Efficiency and Analysis of Influencing Factors in Main Maize Producing Provinces:An Empirical Study Based on DEA-Tobit Model Ding Qi, Yang Yantao, An Yan 2021, 37 (23):  151-157.  DOI: 10.11924/j.issn.1000-6850.casb2020-0582 Abstract + ( 310 )   HTML ( 4 )   PDF ( 1349KB )   ( 46 ) By using maize input-output panel data from China’s 20 provinces (municipalities and autonomous regions) in 2004 - 2018 and using DEA-Malmquist method, this paper analyzed the change of the efficiency of maize production and spatial differences in China and maize input-output redundancy in production within the study phase. At the same time, this paper used Tobit model to analyze the main factors that influencing the efficiency of maize production in China. The results show that technological progress is the main key factor to promote the growth of total factor productivity of maize in China, and the result of improvement of comprehensive technical efficiency is not obvious, which mainly depends on the increase of scale efficiency. Overall, the order of China’s maize production comprehensive technical efficiency from high to low is: the northern spring planting maize area > northwest irrigated maize area > yellow Huaihai summer planting maize area > southwest mountain maize area. In Shanxi, Liaoning, Shandong, Hubei, Yunnan, Shaanxi and Gansu Province, there is insufficient output or redundant input. The total power of agricultural machinery, the damage area and the regional difference have significant influence on the technical efficiency of maize production. Based on the research conclusions, three suggestions are put forward, first, cultivating new technical talents and strengthening the development power of maize; second, improving infrastructure to mitigate the impact of natural disasters; third, implementing structural adjustment policy and carrying out scale moderate management.

  The Coupling Degree of Township Industry and Ecological Protection in Beijing Ecological Conservation Area Liu Yan, Xu Guangcai 2021, 37 (23):  158-164.  DOI: 10.11924/j.issn.1000-6850.casb2021-0336 Abstract + ( 219 )   HTML ( 1 )   PDF ( 1822KB )   ( 37 ) By constructing a model of coupling degree and coupling coordination degree, the authors calculated the coupling degree and coupling coordination degree of industrial development and ecological protection of 37 villages and towns in Beijing’s ecological conservation area, aiming to coordinate the ecological and industrial construction of Beijing’s ecological conservation area. Combining the basic situation of township industry and ecological protection in Beijing’s ecological conservation area, the township industry and ecological protection were set as subsystems, and 16 indicators were selected from the perspective of industrial output value, industrial modernization level and agricultural resources and environment. The entropy method is used to calculate the index weights of industries and ecology, so as to obtain the respective comprehensive evaluation values S (1, Z) and S (2, Z), and the coupling degree C of the ecological conservation area and the degree of coupling coordination D. The results showed that Liubinpu Town, Qianjiadian Town, Jiuxian Town, Yongning Town and Xiangying Town in the northeast of Yanqing District, Yanchi Town in the southwest of Mentougou District, Baoshan Town in the northwest of Huairou District, Bulaotun Town, Dachengzi Town and Taishitun Town in the northeast of Miyun District had relatively low degree of coupled and coordinated development, and they belonged to the barely coordinated development area with poor coordination. Yukou Town, Wangxinzhuang Town in Pinggu District, and Dongshaoqu Town in Miyun belonged to the middle-level coordinated development area with a good degree of coordination. Through the coupling degree and the coupling degree coordination degree model, it was found that the coupling degree values of the 37 towns were relatively high, and there was no obvious difference. From the perspective of the development type of the coupling coordination degree, there was still a great space for the development of coupling coordination among the 37 towns in the future.