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Based on healthy tobacco rhizosphere soil, bacterial strains with diverse functions and high activity were isolated and screened to provide efficient and diversified biocontrol resources for the biological control of crop diseases. The plate confrontation method was used to screen the strains with high activity and wide antibacterial spectrum, and the inhibition rate of the strains on Fusarium oxysporum, mycelia growth and spore germination rate were determined. PCR was adapted to detect the antibiotic synthesis genes of the strains, and the control effects of the functional strains on tomato fusarium wilt were detected by indoor pot experiments. The enzyme production, phosphorus and potassium solubilization, nitrogen fixation and siderophorer production abilities of the functional strains were measured in vitro. The functional strains were identified by combining morphological, physiological and biochemical and 16S rDNA universal primers. A total of 127 strains were isolated from the rhizosphere soil of tobacco, and 24 strains presented the inhibitory effects on Fusarium oxysporum sp. of tomato. The inhibitory rates of 3 top-activity strain SH-1471, SH-1464 and SH-1439 against F. oxysporum sp. of tomato were 82.0%, 74.0% and 75.0%, respectively. It caused the mycelia distortion of F. oxysporum sp. of tomato and vesicle structure was formed, and thus inhibited the spore germination of F. oxysporum sp. of tomato by 62.7%, 50.0% and 37.0%, respectively. The three functional strains had genes for antibiotic synthesis, including srfA, fenB, ituA, ituD and bymA. The results of pot experiment showed that SH-1471, SH-1464 and SH-1439 had 83.7%, 60.7% and 59.0% control effect against tomato fusarium wilt. In addition, the three strains all had the ability of producing protease and cellulase, solubilizing phosphorus, fixing nitrogen, and secreting siderophores. The SH-1471 was identified as Bacillus amyloliquefaciens (Gen-bank ON417363), and SH-1464 as Bacillus paramycoides (Gen-bank ON417365) and SH-1439 as Bacillus siamensis (Gen-bank ON417364) . Strains SH-1471, SH-1464 and SH-1439 have high-efficiency and broad-spectrum antibacterial ability and diversified functions, and they may be used as efficient biocontrol resources for a variety of diseases and had great development potential. [ABSTRACT FROM AUTHOR]

By planting different pepper varieties (combinations) and identifying their disease resistance, select pepper varieties (combinations) with disease resistance. 【Method】According to the disease characteristics and pathogen characteristics of blight, powdery mildew, anthracnose and viral diseases, combined with inoculation and natural disease comprehensive analysis, the resistance level of the combination materials of pepper varieties was evaluated. [Results] The 15 pepper varieties (combinations) showed great differences in their resistance to susceptibility. The pepper varieties (combinations) Hongtai 664, Hongtai 668, Yujiao 13, and combinations 1-1 and 5-1 were resistant to blight and powder The comprehensive disease resistance of anthracnose, anthracnose and virus disease is strong; followed by comprehensive disease resistance of Yanjiao 435, Yanjiao 465, Yujiao 15, Combination 3-1, 4-1, 6-1 and 7-1 The middle-to-upper level; the comprehensive disease resistance level of combination 2-1 is average; the susceptible varieties Xiaomi La and Chaotian pepper are both susceptible, and the resistant variety Yunganjiao No. 7 is resistant. [Conclusion] Pepper varieties with comprehensive disease resistance above medium resistance can be planted in rotation in pepper production, and combinations of peppers with disease resistance and above can be used as resources in breeding, providing a theoretical basis for the selection and promotion of disease-resistant pepper varieties. [ABSTRACT FROM AUTHOR]

[Objective] In order to select the effective chemical agents and the staining method for detecting spore activity, the lethal effect with different treatments on the spores suspension of Plasmodiophora brassicae were determined. [ Method] In this study, different chemical agents were added to the spores suspension of Plasmodiophora brassicae in proportion, and the lethal effect of test chemical agents on Plasmodiophora brassicae was detected by trypan blue staining method. [ Result] The result showed that there were significant differences in the lethal effects of Plasmodiophora brassicae with 19 test chemical agents, the fatality rate of Mingdi, Fushuaide, Kejia, Chlorothalonil and Chlorothalonil were 55. 99 % -62. 49 %, and the other agents treatments were 17. 89 % - 33. 89 % . The spore mortality increased gradually with time after treatment, and the lethality order was 14 days> 10 days> 7 days. Among them, the range of fatality rate of Mingdi, Fushuaide, Kejia, Chlorothalonil and Carbendazim with 7 -10 days greater than that with 10 -14 days, and there was no significant difference in the fatality rate between other treatments. The lethal effect of test chemical agent& determined in this experiment was basically consistent with the control effect in the field. [ Conclusion] Due to fungicides had timeliness and hysteresis quality in the prevention and treatment of Plasmodiophora brassicae. Therefore, we should apply chemical agents in advance or take preventive measures. Using only a single agent to prevent and control was useless, and comprehensive prevention and control measures must be adopted to reduce the occurrence and ham, of Plasmodiophora brassicae. [ABSTRACT FROM AUTHOR]

[Objective] In order to provide efficient microbial resource for the development of green agricultural inputs, we identified potential high-activity microbial strains from the National Wilderness Preservation System of Mount Wuliangshan. [Method] We used Fusarium oxysporum as a target to screen highly antagonistic strains, and observed the effect on hyphae growth and spore germination. We also tested the lipopeptide synthesis genes and the ability of the strain to produce enzymes, hydrolyze phosphorus, hydrolyze potassium, fix nitrogen and produce siderophore. In addition, the strains were identified according to their morphological, physiological and biochemical characteristics and 16S rRNA, gyrA and rpoB genes, and the effects of disease control and growth promotion were verified by pot experiment. [Result] A total of 153 strains of culturable bacteria were isolated and screened. Among them, the inhibition rates of SH-53, N4471 and N9456 were 92.35%, 87.29% and 88.47%, respectively, it showed good antagonistic activity against many pathogens, and also inhibited the hypha growth and conidia germination of the pathogen. The three functional strains all had the abilities of dissolving zinc, producing amylase and protease, and the strains Sh-53 and N4471 also had the abilities of dissolving phosphorus, fixing nitrogen, secreting cellulase and producing siderophore. In addition, we found that srfA, fenA, ituA, ituC, ituD and bymC genes were found in the genomes of the three functional bacteria. Strain SH-53 was identified as Bacillus amyloliquefaciens, N4471 as B. cabrialesii, and N9456 as B. siamensis. The results of pot experiment showed that the control effects of the three functional bacteria were 84.66%, 54.96% and 59.74%, respectively. They promoted the agronomic characters of tomato seedlings, such as plant height, stem diameter and root length. [Conclusion] As high-efficiency microbial resources, the three strains have broad-spectrum antibacterial activity, diverse biological activity, and have broad application prospects in the development of green agricultural inputs. [ABSTRACT FROM AUTHOR]

【Objective】Functional strains with multiple biological activities were excavated from the forest rhizosphere soil of Wuliangshan National Nature Reserve, and their potential for development and application was explored.【Method】The 25 rhizosphere soil samples from different regions and plants in Wuliangshan National Nature Reserve were collected. The active strains with functions such as phosphate dissolution, nitrogen fixation, zinc dissolution, and antibacterial activity were isolated and identified using selective culture medium. The biological activities of these strains, such as secreted siderophore, ACC deaminase, and indoleacetic acid, were tested while verifying their effectiveness in promoting tomato seed germination and plant growth.【Result】70 phosphorus-dissolving bacteria, 27 nitrogen-fixing bacteria, 8 potassium-dissolving bacteria, and 51 antibacterial bacteria were isolated and identified. Among them, YIM B08401 and YIM B08402 were identified as Burkholderia alba and Pseudomonas qingdaonensis based on morphological, physiological, biochemical characteristics, and 16S rDNA sequencing. The two strains both had the activities of phosphate lysis, nitrogen fixation, zinc lysis and siderophore secretion. Their maximum soluble phosphorus content was（455.63±59.65）mg/L and（878.95±64.78）mg/L. The results of seed germination promotion tests of the two strains were similar, and the germination rates of the two strains were maintained at 82%-93% after applying the fermentation supernatant diluted 10 times, 102 times and 103 times, which was significantly higher than 56% and 49% in the control group. The length of the treatment group with the fermentation liquid of the strain significantly increased compared with the blank control group. Pot experiment showed that the above ground length, fresh weight, dry weight, stem diameter, root length, fresh weight and dry weight of the two strains in the treatment group with the most obvious growth promotion effect were significantly better than that in the control group. Compared with the control group, the above indexes of YIM B08401 significantly increased by 89%, 495%, 268%, 62%, 53%, 385% and 469%, and the above indexes of YIM B08402 significantly increased by 118%, 528% and 477%, 55%, 37%, 413% and 747%, respectively. In addition, strain YIM B08401 also had activities of antagonizing pathogenic bacteria and secreting ACC deaminase, and YIM B08402 also had the activity of secreting indoleacetic acid. 【Conclusion】The rhizosphere soil in the forest of Wuliang National Nature Reserves contained a variety of strains with biological activity. B. alba YIM B08401 and P. qingdaonensis YIM B08402 demonstrates the potential for the development and application of new microbial fertilizers [ABSTRACT FROM AUTHOR]

[Objective] The unreasonable structure of plough layer, nutrient loss and unbalance of microbial structure in tobacco-growing soil are the important conditions that restrict the sustainable production of tobacco, the effects of different tillage and fertilization modes on the physicochemical properties and microorganisms of rhizosphere soil, and yield of flue-cured tobacco were studied to provide a theoretical basis for optimizing tobacco production and management techniques in Baoshan. [Method] Traditional rotary tillage, deep tillage with chemical fertilizer and biological organic fertilizer, respectively, were set up, and Illumina MiSeq sequencing technology was used to analyze the response characteristics of rhizosphere microorganisms of different treatments, and soil physical and chemical properties, biological activity and yield of flue-cured tobacco were analyzed. [Result] Compared with traditional rotary tillage, soil organic matter, sucrase activity, urease activity, and microbial biomass carbon decreased by 17.00%-25.10%, 22.45%-23.47%, 2.20%-7.49%, and 11.38% -65.73%, respectively, whereas, the microbial biomass nitrogen increased by 10.56%222.86%. Deep tillage combined with bio-organic fertilizer did not affect the microbial abundance and diversity of rhizosphere soil of flue-cured tobacco, but changed the community composition of soil bacterial phyla and fungal phyla, the abundance of Actinobacteria, Chloroflexi and other dominant bacteria were enriched, and the relative abundance of Mortierellomycota reduced, the yield of flue-cured tobacco increased by 56.66%. The results of redundancy analysis showed that soil Actinobacteriota and Myxococcota significantly correlated with pH, while Basidiomycota significantly correlated with alkalinehydrolyzed nitrogen. [Conclusion] Deep tillage combined with bio-organic fertilizer could improve soil properties and microbial community composition of tobacco field, and increase economic benefit of tobacco leaves. The results can provide reference for deep tillage and bio-organic fertilizer in improving soil environment and increasing tobacco yield. [ABSTRACT FROM AUTHOR]

【Objective】In order to provide the scientific basis for obstacles research and development, nutrient management and high-quality flue-cured tobacco production in regional tobacco planting soil, the characteristics of main obstacles to tobacco planting soil in 5 counties（cities, districts）of Baoshan city were analyzed.【Method】The samples of tobacco planting soil were collected from 72 villages in 24 towns in 5 counties of Baoshan city.Total of 12 indexes, including pH, organic matter（OM）, total N（TN）, total P（TP）, total K（TK）, alkaline N（AN）, available P（AP）, available K（AK）, soil bulk density（BD）, field water holding capacity（FC）, sucrase invertase（INV）and urease（URE）, were selected as the total data set（TDS）to construct the minimum data set（MDS）, and the soil quality index was calculated, and the main obstacle factors were analyzed by using the diagnosis model of obstacle factors.【Result】By K-S test, the 12 indexes complied with the normal distribution and were included in TDS. Six indexes including OM, TP, AN, AP, BD and INV were included in the MDS by principal component analysis.The MDS-SQI of soil quality index was positively correlated with TDS-SQI, and the MDS could represent the TDS to evaluate the soil quality in Baoshan tobacco planting area.The MDS-SQI soil quality indexes in Shidian county, Changning county, Longyang district, Longling county and Tengchong city were 0.681, 0.668, 0.665, 0.626 and 0.579, respectively.The obstacle degree analysis showed that the main obstacle factors were FC（average obstacle 0.251）, AN（average obstacle 0.196）, pH（average obstacle 0.142）and OM（average obstacle 0.110）.【Conclusion】The established MDS of soil quality assessment has certain representativeness and accuracy, which can be used to evaluate and diagnose soil quality and obstacles. [ABSTRACT FROM AUTHOR]

【Objective】 Based on the long-term positioning experiment of organic carbon source material application, the response characteristics of rice rhizosphere anaerobic microbial community diversity to organic carbon source material input in Erhai lake basin were analyzed. 【Method】 Three treatments as non-fertilizer（CK）, chemical fertilizer（T1） and corn straw combined with chemical fertilizer（T2） were set to analyze the diversity characteristics of rice rhizosphere anaerobic microbial communities based on nitrogen conversion functional genes（nifH） and carbon conversion functional genes（cbbL）. The correlation between soluble N and P contents in soil and anaerobic microbial population was analyzed using redundancy analysis（RDA）. 【Result】 The results of Alpha and Beta diversity analysis showed that the Observed species, Shannon index and Chao1 index significantly improved（P<0.05）, and the difference of anaerobic microbial community structure significantly enhanced. Moreover, long-term application of organic carbon source material significantly increased the relative abundance of Proteobacteria and Cyanobacteria（P<0.05） at the phylum level. At the genus level, the population abundance of Methylibium and Bradyrhizobium increased, while the population abundance of Paraburkholderia decreased. In addition, the relative abundance of Cupriavidus taiwanensis and Alkaliphilus oremlandii significantly increased at species level（P<0.05）,however, Azohydromonas lata and Sulfuricaulis limicola decreased（P<0.05）. The results of redundancy analysis showed that soluble N had the highest resolution to the anaerobic microbial community. 【Conclusion】 In the high carbon storage farmland of Erhai lake basin, corn straw combined with chemical fertilizer mainly affected the community structure, physiological and ecological functions of rice rhizosphere anaerobic microorganisms by regulating the content of soluble nitrogen in the soil, and then affected their carbon and nitrogen conversion process. The results of the study have a certain role in promoting the accurate prediction of the changes of carbon, nitrogen and microbial structure in rice field and their influencing pathways, and can provide a theoretical basis for the optimization of regional farmland ecosystem management measures and the reasonable protection of farmland ecosystem. [ABSTRACT FROM AUTHOR]

【Objective】 This paper aimed to study the pathogen and biological characteristics of three leaf diseases of Amomum tsaoko Crevost et Lemarie in Yunnan province, and to provide theoretical basis for the control of leaf spot of A.tsaoko. 【Method】Three fungal diseases were discovered from A.tsaoko plantation in Nujiang Prefecture, Yunnan province. Three strains, including CG-N01, CG-N02 and CG-N03 were obtained by single spore culture, their pathogenicity was determined, spore morphology was observed according to morphological characteristics, and pathogen was identified by phylogenetic tree constructed by multi-gene sequence analysis (rDNA-ITS, tub2, LSU and tef-1 α), and biological characteristics were determined. 【Result】 The morphological characteristics of CG-N01, CG-N02 and CG-N03 were in accordance with the typical characters of Pyrus costina, Phoma matteuccola and Colletotrichum mondsii, respectively. The rDNA-ITS, LSU and tef-1 α sequences of CG-N01 were 489, 901 and 475 bp, respectively ( the login numbers were MN596209, MN689811 and MN696687, respectively) ; The rDNA-ITS, LSU and tef-1 α sequences of the strain CG-N02 were 517, 997 and 529 bp respectively (the login numbers were MN596212, MN650644 and MN696686, respectively) ; The rDNA-ITS, tub2 and tef-1 α sequences of strain CG-N03 were 560, 926 and 738 bp, respectively ( the login numbers were MN596210, MN650645 and MN696688, respectively). Purified strains of CG-N01, CG-N02 and CG-N03 had high homology with P. costina, P. matteuccola and C. simmondsii, respectively. Biological determination showed that strain CG-N01 was advantageous to mycelium growth and conidia formation under the conditions of 28 ℃, alternating light and dark, and pH 6.0. Strains CG-N02 and CG-N03 were favorable for sporulation at 25 ℃, alternating light and darkness, and pH 8.0. 【Conclusion】 This study first reported that C. simmondsii can infect and cause Colletotrichum gloeosporioides, the biological characteristics of the pathogens of leaf spot, leaf blast and anthracnose were determined to provide scientific basis and theory support for the diversity study and effective control of the disease. [ABSTRACT FROM AUTHOR]

【Objective】The microbial community diversity characteristics of alkaline tobacco planting soil in Baoshan Mountains were analyzed, and the inhibition effect of deep tillage and application of bio-organic fertilizer on soil quality degradation was investigated, so as to provide theoretical basis for the optimal management of regional tobacco planting soil. 【Method】With deep ploughing (30 cm) as the main treatment, and bio-organic fertilizer cultivation as the secondary treatment, a random block experiment was set up to analyze and test the main physical and chemical properties, enzyme activities and microbial community structure of the soil; analyze the main physical and chemical properties and enzyme activities of the soil relationship with microbial population abundance. 【Results】The treatment of deep tillage + chemical fertilizer + bio-organic fertilizer (treatment CS) significantly decreased soil bulk density and pH by 28.64% and 9.21%, respectively; significantly increased soil organic matter, total phosphorus, available phosphorus and available potassium content, as well as invertase and urease activities, 31.54%, 21.63%, 165.31%, 77.34%, 21.68, 27.95% and 238.55% respectively. The results of Alpha and Beta diversity analysis showed that there was no significant difference in bacterial Chao1 index and Shannon index among the treatments; CS treatment significantly increased the fungal Chao1 index and Shannon index (P<0.05), which promoted the enhancement of bacterial and fungal community differences, and affected the fungal community structure. The effect of composition is more pronounced. The results of community structure showed that CS treatment significantly increased the abundance of Proteobacteria and Mortierellomycota by 74.32% and 280.70%, respectively; The population abundance of Chloroflexi, Actinobacteria and Basidiomycota decreased by 12.83%, 21.88%, 36.57% and 70.04%, respectively. LEfSe analysis showed that CS treatment resulted in an increase in significantly different species of bacteria and fungi at the genus level. The results of BugBase phenotype prediction and FUNGuild functional prediction showed that CS treatment significantly affected soil microbial functional groups, among which the abundance of pathogenic bacteria and phytopathogenic fungi decreased significantly. The correlation results showed that soil bulk density and pH were the main physicochemical factors affecting soil bacterial and fungal community structure. 【Conclusion】Deep tillage and application of bio-organic fertilizer reduce soil bulk density and pH, increase organic matter and nutrient content, promote the formation of soil microbial functional diversity, and improve soil enzyme activity, which are effective measures to improve the quality of alkaline tobacco planting soil. [ABSTRACT FROM AUTHOR]

[ Objective]The purpose of this study was to analyze the characteristics of soil bacterial diversity in rape-rice rotation farmland in Erhai basin, so as to further explore the impact of water and drought rotation on soil microbial diversity. [ Method] Using microbial ribosomal RNA gene targeting sequencing technology and fluorescence quantitative PCR technology, the change characteristics of oil bacterial population abundance and carbon - nitrogen conversion function gene abundance were studied. Further, the relationship between bacterial diversity, population structure and soil carbon, nitrogen was analyzed combined with Perason correlation analysis. [Result] The results showed that soil organic matter ( OM) and total nitrogen ( TN) were negatively correlated with the relative abundance of Proteobacteria and Actinobacteria, and positively correlated with the relative abundance of Chloroflexi and Actinobacteria. For rape and rice planting seasons, the number of clean tags, the abundance of OTUs and the diversity index between different treatments were not significant ( P ⩾5) and the dominant bacterial populations at the phylum level Will not significant ( P ⩾5). The qPCR results showed that there was no significant difference between treatments of the copies of cbbl-R gene and amoA, while the copies number of niflH and amoA gene were significantly increased by applying organic carbon source materials (P < 0.05). [Conclusion]The changes of soil bacterial diversity, population structure and carbon and nitrogen conversion gene abundance were similar in rape and rice planting seasons. The effect of crop rotation on soil bacterial diversity was not significant, and its stability might be related to the soil background of higher carbon and nitrogen content. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to clarify the effect of disease prevention and growth promotion on Amorphophallus konjac by using bulbs coating chemicals, provide data support for the sustainable development of Amorphophallus konjac industry. 【Method】In this study, four different experimental treatments were set up, and the tubers were treated before the sowing. The effects of using bulbs coating chemicals on the seedling rate of Amorphophallus konjac, the disease incidence and mortality of its soft rot disease in the test plot were regularly researched. And real-time quantitative PCR(RT-qPCR) technique was developed and used to quantitatively detect Erwinia carotovora subsp. carotovora in soil. 【Result】Using bulbs coating chemicals could effectively improve the seedling rate and plant growing. The result showed solid bulbs coating chemicals > liquid bulbs coating chemicals > 72 % agricultural streptomycin > CK on the disease incidence and mortality of Amorphophallus konjac soft rot disease. The lowest concentration of Erwinia carotovora subsp. carotovora in soil detected by the developed system was 5(10~4 CFU/mL. 【Conclusion】The number of Erwinia carotovora subsp. Carotovora, the incidence of konjac soft rot and plant mortality could be significantly reduced by using bulbs coating chemicals or antibiotic pestside(P<0.05). [ABSTRACT FROM AUTHOR]

【Objective】The study aimed to clarify the application of biochemical fulvic acid potassium product on the survival rate and growth of various trees transplanted in the process of landscaping. 【Method】In this study, two experimental treatments(i.e. decomposed organic fertilizer + biochemical fulvic acid potassium water soluble fertilizer, decomposed organic fertilizer + compound fertilizer) were set up to determine the changes of physical and chemical properties before and after soil treatment, and the survival rate, plant height and ground diameter of four different cultivated plants in one year, and the effects of adding biochemical fulvic acid potassium on cultivated plants were investigated. 【Result】The results showed that the soil organic matter, total nitrogen, alkali-hydrolyzable nitrogen, soil available phosphorus, soil available potassium, the pH value in the soil treated with decomposed organic fertilizer + biochemical fulvic acid potassium soluble fertilizer, decomposed organic fertilizer + compound fertilizer increased significantly, and the soil bulk density decreased obviously. The survival rate, plant height and ground diameter of the four different cultivated plants were significantly improved after the treatment with decomposed organic fertilizer + biochemical fulvic acid potassium water soluble fertilizer, decomposed organic fertilizer + compound fertilizer(P<0.05). 【Conclusion】The application of biochemical fulvic acid potassium on cultivated plants and effectively improve soil fertility, increase the utilization of nitrogen, phosphorus and potassium, improve the growth of plants, and promote the landscaping plants. [ABSTRACT FROM AUTHOR]

[Objective] A long-term positioning experiment of no-tillage organic fertilization was carried out to investigate the effects of conservation tillage on soil quality and crop yield in the typical red soil sloping cropland in central Yunnan Province. [Method] In this study, notillage without organic fertilization treatment (NA) was used as a control experiment, and long-term positioning experiment of no-tillage organic fertilization (NE) was set up, and the effects of NE on soil quality and crop yield were studied from 2015 to 2018. [Result] The results showed that the field moisture capacity increased by 10.26% and 9.46%, and the water content of soil increased by 6. 32% and 9.11% in NE treatment in the depth of 0-20 cm and 20-40 cm, respectively. The soil pH in the three soil layeis of 0-20 cm, 20-40 cm and 40-60 cm increased by 10.80%, 7.19% and 3. 54%, the organic matter increased by 18.47%, 23.02% and 30.86%, the soil total nitrogen increased by 11.28% ,17.86% and 16.22%, the soil available nitrogen increased by 7.33%, 16.21% and 7.36%, respectively. The bacterial abundance of Pmteobacteria, Ac ido bacteria and Gemmatimonadetes increased by 23.65%, 39.72% and 42.08%, and the abundance of Chlorojlexi and Adinobacteria was reduced by 53.03% and 49.15%, respectively. The biomass of com stalks in-creased by 10.86% and the yield of com increased by 20.09%. [Conclusion] No-tillage organic fertilization is an effective measure to realize the rational tillage construction of red soil sloping cropland, which can improve soil quality,crop yield and bacterial population structure. [ABSTRACT FROM AUTHOR]

【Objective】 In order to increase the biomass of the strain S. malaysiensis ECO-00002, the seed medium composition and culture conditions were optimized. 【Method】 The Plackett-Burman test was used to screen the carbon and nitrogen sources for seed culture medium, and the Response Surface Analysis test was used to identify the most significant factors and to determine their optimal values. Furthermore, the proportion of multivitamins, complex salts, and CaCO3 were determined. The initial pH of the medium and liquid volume were optimized by comparative tests. 【Result】 The optimization results showed that the growth of the strain seed mainly affected by the carbon source which were glucose, yeast extract and malt extract, and the maximum response values of the three factors were 1.45 %, 1.50 %, 2.00 %, respectively. The inorganic salt was as follows: CaCO3 3.00 g/L, MgSO4·7 H20 1.00 g/L, MnSO4·4 H20 0.10 g/L, KH2PO4 0.20 g/L. Initial pH was 7.50, and liquid volume was 100 mL/500 mL. The optimization of culture conditions was as following: culture temperature was 28 °C, and incubation time was 200 r/min with shaking culture 40 hours. 【Conclusion】 Under the optimized seed culture conditions, the biomass yield increased from 4.09 g to 8.91 g, and the increase rate was 117.70 %. The optimization effect was significant. [ABSTRACT FROM AUTHOR]