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【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 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] The effects of deep ploughing on soil characteristics and maize yield of red soil sloping land,and the suitable subsoiling depth and operation measures were selected to provide a basis for the rational construction of red soil sloping land. [MethodsJin this study, four different tillage treatments including conventional rotary tillage 20 cm (CK) , no-tillage (SO) , subsoiling 30 cm (S30) and subsoiling 40 cm (S40) were set up. The planting methods was sowing maize with identical field management and fertilization methods. [ ResultsjThe results showed that treatments SO, S30 and S40 had no significant died on maize yield, but in the first year, the biological yield increased significantly by 11.66 % , 14.69 % and 5. 07 % , respectively. In the second year, the yield increased by 3. 22 % ,22. 03 % and 14. 14 % , respectively. The biological yield increased —1.81 % , 15.61 % , 5. 27 % , respectively; In the third year, the yield of corn increased by 28.71 % , 22.00 % and5.69 % , respectively, the biological yield increased by 16.86 % , 14.86 % and 3.76 % , respectively. In the 0-20 cm soil layer, with SO treatment, soil bulk density decreased by 2. 83 % in three years, soil compaction increased by 33.20 % , soil water content decreased by 5.73 % ; with S30 treatment, soil bulk density and soil compaction reduced by 3. 88 % and 3.95, respectively, soil water content increased by 5.44 % ; with S40 treatment, soil bulk density decreased by 0. 52 % , soil compaction increased by 7.70 %. In the 20 -40 cm soil layer, with SO treatment, soil bulk density decreased by 3. 41 %, the soil compaction increased by 7. 54 % , the soil water content increased by 6.21 % ; with S30 treatment, soil bulk density decreased by 9. 23 % , llie soil compaction decreased by 20. 27 % , and llie soil water content increased by 13. 80 % ; with S40 treatment, soil weight loss decreased by 8.79 % , soil compaction decreased by 15. 38 % , and soil water content increased by 7.99 %. In ihe 40 -60 cm soil layer, with SO treatment, soil bulk density decreased bv 3. 17 % , soil compaction increased by 35.53 % , soil water content increased by 2. 86 % ; with S30 treatment, soil bulk density decreased by 1.48 % , soil compaction increased by 21.93 % , soil water content increased by 3. 00 % ; with S40 treatment, soil weight loss decreased by 4. 86 % , soil compaction decreased by 2. 84 % , soil water content increased by 7. 84 %. [Conclusion] Deep ploughing was a suitable tillage measure that could promote the yield of maize on the slope of red soil in Yunnan Province, and the suitable depth of subsoiling was 30 cm in this experimental area. [ABSTRACT FROM AUTHOR]

【Objective】 In order to effectively control the tobacco bacterial wilt disease caused by Ralstonia solanacarum, meteorological epidemic factors and soil conditioner controlling strategies were studied. 【Method】 The plots with tobacco bacterial wilt occurred over the years were selected and the incidence of the disease was periodically surveyed in tobacco growth period in 2012, 2103 and 2014, respectively. 10 d effective accumulated temperature and rainfall were counted according to the meteorological data. The relationship between meteorological factors and the disease index was analyzed. The controlling effect of three kinds of soil conditioner ‘ Zhuanggenfeng', humic acid and lime on tobacco bacterial wilt were tested. 【Result】 The meteorological factors analysis results showed that 10 d effective accumulated temperature and rainfall were positively correlated to the disease index. The change curve of 10 d effective accumulated temperature and rainfall reflected the change trend of the disease index. The pH increasing values were 0. 57, 0. 50 and 0. 72 respectively after applying ‘ Zhuanggenfeng' , humic acid and lime, the controlling effect were 60.74 %-62. 18 %, 53.05 %-59.53 %, 48.59 %-58.53 %, respectively. 【Conclusion 】10 days effective accumulated temperature and rainfall could be used as important reference for disease forecasting and controlling. The usage of soil conditioner had a certain controlling effect on tobacco bacterial wilt disease which was an auxiliary method on the disease. [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]

[Objective] The purpose of the present study was to explore the control measures which could effectively prevent clubroot disease and control the incidence and epidemic of this disease. [Method]The control effect of 4 chemical fungicides, 3 soil amendments and 4 crops rotation were investigated by testing the pathogen content in field with qPCR and surveying disease incidence of rape. [Result]The disease incidence of oilseed rape treated with Mingdi and Fushuaide was low, respectively 73.33 % and 77.42 %. The pathogen quantity in soil treated with Mingdi was 1.7 x 107 copy number/g, which was significantly lower than control. The disease incidences of oilseed rape treated with anti-continuous cropping agent, complex microbial community and organic silicon fertilizer were lower than control and the pathogen quantity of those 3 kinds of soil amendment was significantly lower than control. The pathogen quantity with 2.2 x 107copy number/g in the garlic rotation soil was the lowest and significantly different with that in the soil of control, barley, broad bean and potato rotation. [Conclusion] Mingdi, Fushuaide, complex microbial community and garlic rotation had a certain control effect on clubroot. According to the degree of disease in the production, it would achieve the goal of continuously controlling the disease to integrate ' rotation + soil regulation + diseased root clean + chemical fungicide control ' technologies. [ABSTRACT FROM AUTHOR]