 |
| About Bioline | All Journals | Testimonials | Membership | News |
|
||||||
|
||||||
Characteristics Of The Populations Of Soil Actinomycetes In Yunnan C.-L.JIANG and L.-H.XU Yunnan Institute of Microbiology, Kunming, Yunnan, China
Abstract. Soil samples have been collected from areas with various vegetational and climatic types in Yunnan and the actinomycete population investigated. The correlation between the actinomycete population and climatic type, vegetational type and other ecological factors is discussed. Yunnan province is in the southwest of China, between latitudes 20 degrees 09' to 29 degrees 15' north and longitudes 97 degrees 39' to 106 degrees 12' east. The area covers 436,200 km^2. Yunnan has a varied topography, high in the northwest and low in the southeast. Meili, Baima, Yulong and Haba Snow-Mountain tower aloft on the northwest of Yunnan. Kalipo, the peak, is 6,740 m above sea level. These constitute the Hengduan Mountain Chain. Hekou, a small town in the southeast, is only 67 m above sea level. The main part of Yunnan is named Middle Plateau of Yunnan averaging about 2,000 m, and is the most-developed area. There, the varied climates including all types from Helong River to Hainan Island of China. There are wide ranges of tropical, subtropical and cool temperate forests and a half of the plant species of the whole China is represented in Yunnan. So Yunnan was named 'plant kingdom' and 'animal kingdom' for a long time. But it is a virgin, mystical land for microbiologists. Table 1. General characteristics of sampling sites.
No. Area Altitude Average Annual
(m) annual rainfall
temp.(C) (mm^3)
--------------------------------------------------
I Mengna 690-890 20.9 1523
II Menglun 550-950 21.0 1500
III Yuangjian River 450-800 23.8 800
IV Ailo Mountain 2400-2700 7.5 1840
V Diaoling Mountain 2000-2500
VI Kunming 1900-2200 14.7 1011
VII Jinsha River 2100 16.2 300
VIII Zhongdian Plateau 3100-3300 5.4 600
IX Youlong Snow Mt. 2600-3000
4.7 660
XI Middle Plateau 1850-3150 15.0 1000
of Yunnan
XII Baoshan 620-2310 14.8 1467
II Northeast of 550-1400 13.3 1056
Yunnan
Table 1 Continued
No. Soil Soil Organic
type pH Matter
%
-------------------------------------
I laterite 5.3 3.22-3.85
II laterite 5.3-5.5 3.04-5.63
III dry red 5.4-5.6 2.4-5.3
IV yellow brown 4.5
V yellow brown 5.5
VI red 5.5 12.9
VII dry red 5.5 2.25-4.25
VIII dull brown 5.2-5.5 6.25-9.90
IX brown 5.4 11.5-22.9
X dull brown 5.2-5.5 13.9-24.0
XI red 5.7-5.7 7.8-33.6
XII red 5.5-6.5 7.4-18.4
XIII yellow 5.0-5.7 5.65-15.3
Table 2. Actinomycete population of some areas in Yunnan (10^3 cfu/g dry soil)
Genus I II III IV V VI -------------------------------------------------------------- Streptomyces 354.9 815.6 829.8 287.5 259.2 3293.6 % 83 92 83 92 94 86 Chainia 0.34 2.9 Actinosporangium 0.8 0.3 Streptoverticillium 1.0 0.03 Micromonospora 29.7 11.9 43.6 3.7 12.0 187.2 Actinoplanes 1.66 6.8 2.0 2.0 32.0 Ampullariella 6.2 Dactylosporangium 1.6 0.8 Streptosporangium 0.1 0.1 0.3 0.6 5.8 Actinomadura 1.2 15.5 28.1 0.8 0.02 116.2 Microbispora 0.2 Microtetraspora 0.4 Micropolyspora 0.3 1.5 Pseudonocardia 0.6 Saccharomonospora Saccharopolyspora 9.6 10.7 45.0 30.8 Nocardia 13.1 18.2 39.0 7.9 2.0 138.8 Rhodococcus 11.9 17.4 15.4 Mycobacterium 0.1 Promicromonospora 25.0 Thermoactinomyces 0.1 0.05 2.0 1.1 Non-identified 1.9 0.9 4.4 5.3 Total 426.8 890.7 1008.2 313.3 275.2 3838.5 No.of genera 12 9 10 14 6 10 Table 2 continued Genus VII VIII IX X XI XII XIII -------------------------------------------------------------- Streptomyces 1130.0 1022.2 1116.1 394.8 4428.4 1297.3 707.5 % 97 99 99 98 93 92 85 Chainia 0.4 1.2 Actinosporangium 0.3 0.2 4.8 1.2 Strepto- verticillium 0.6 Micromonospora 6.9 2.6 2.2 3.4 60.9 41.0 51.4 Actinoplanes 0.4 0.6 Ampullariella Dactylo- sporangium 1.2 Strepto- sporangium 0.6 0.8 4.1 3.0 Actinomadura 19.0 1.8 1.4 10.8 18.9 11.8 Microbispora 4.0 5.9 1.5 Microtetraspora 9.0 5.3 Micropolyspora Pseudonocardia Saccharo- monospora 2.9 1.2 Saccharo- polyspora 2.9 4.6 2.1 0.4 140.4 20.3 3.2 Nocardia 1.3 0.6 0.6 82.6 14.1 42.4 Rhodococcus Mycobacterium Promicromonospora 0.6 Thermo- actinomyces 0.09 0.06 0.02 0.04 30.1 0.2 0.9 Non-identified 2.9 2.0 1.1 5.5 Total 1162.5 1033.5 1123.2 401.1 4763.6 1416.1 837.2 No.of genera 5 8 6 6 11 12 14 Since 1980, we have collected 1,100 soil samples from various vegetational and climatic zones in Yunnan, and examined the actinomycete population of 12 selected areas with the intention of screening the isolates for potentially useful metabolites. Materials And Methods Soil Samples. Soil samples were collected from some areas (Table 1) and put in sterilized paper sacks in March or April every year. The actinomycetes were isolated 5 to 10 days after sampling. Isolation and Enumeration of Actinomycetes. Actinomycetes were isolated by spreading sample dilutions on glycerol asparagine agar, starch casein agar, tyrosine agar, AV agar (Jiang et al., 1985), and HV agar (Nonomura et al., 1988). The plates were incubated at 28 C for 15 to 30 days before the colonies were counted. For isolating thermophilic actinomycetes the soil samples were air-dried at room temperature and then dry heated at 120 C for 1 hour. Dilutions were spread on 1/2 strength nutrient agar, tyrosine agar, yeast extract malt extract agar, glycerol asparagine agar, and the plates incubated at 55 C for 5 to 7 days. Cultures were obtained from isolated colonies and checked for purity. Taxonomic Grouping of Isolates. For the taxonomic grouping of isolates the methods described previously were used (Jiang et al., 1985-1986). Results And Discussion Correlation Between Actinomycete Population and Climate. Four types of population were found: -The tropical type. The tropical area includes Mengna, Menglun (latitudes 21 degrees 05') and Yuanjiang River (latitudes 23 degrees 40') (Tables 1-3). Table 3. Actinomycete populations in Yannan
Number of Percentage Number
actinomycetes of of
Type (10^3/g dry wt) streptomycetes genera
----------------------------------------------------------
Tropical 775.3 86 10
Sub-tropical Plateau 1903.3 90 11
Cool Temperate Mt. 1106.4 98 6
Snow Mountain 92.9 83 5
Actinomycete numbers and genera are rather similar. Total counts of actinomycetes in samples averaged 775.3x10^3/g dry weight. Streptomyces strains constituted 86% of total count of actinomycetes. 10 genera were found. Mengna and Menglun are typical, tropical season forest with abundant rainfall. But Yuanjiang River is a dry, hot valley with very little forest left. Their climate and vegetation are different. Why are their actinomycete populations very similar? A hundred years ago the forest cover was up to about 70%, and was also of the tropical type. The cover was 61.5% until 1958, and below 15% in 1982 (Xu et al., 1985). The similarities of actinomycete population reflected the similarities of climate and vegetation in the three areas. -The subtropical plateau type. This type contains a wide area ranging from 1,600 m to 2,600 m of Yunnan Plateau, the northeast of Yunnan (latitudes 27 degrees 30') to Baoshan (latitudes 25 degrees ).The average annual temperature is about 15 C. Main types of soil are red soil and yellowish brown soil by the international classification. The type of vegetation is evergreen broad-leaf forest. Total counts of actinomycetes in soil samples averaged 1,903.3x10^3. Streptomyces strains comprised 90% of the total count of actinomycetes. 11 genera were found, including Microbispora, Microtetraspora, Actinomadura and Saccharopolyspora. -The cool temperate mountain type. This type consists of mountains in the northwest of Yunnan, 3,000 to 3,900 m above sea level. The average annual temperature is about 5 C. The vegetation is typical of a cold temperate dark forest (Liu et al., 1984a). Organic matter in soil is very abundant. Total count of actinomycetes in soil samples averaged 1,106.4x10^3. Streptomyces strains constituted up to 98% of total count. Only about 6 genera were isolated. - The snow mountain type. This type contains the snow mountains in the northwest, 3,900 to 4,400 m above sea level. The average temperature of year is below zero, and very humid. The vegetation is represented by alpine scrubs and meadows, including Rhododendron primulaeflorum, Rh. nivale, Salix sp., Combresia pygmea, Polygonum sp. and Abies georgei among others. Organic matter is extremely abundant. Total count of actinomycetes was only 92.9x10^3. Streptomyces, Micromonospora Actinomadura, Saccharopolyspora and Nocardia were isolated. Streptomyces strains constituted 83%, some of which were psychrophilic with an optimum growth temperature at 10 to 15 C (Jiang et al., 1988). Correlation Between Actinomycete Population and Vegetation. The results of Table 4 to 10 indicate that total counts of actinomycetes increase progressively by the sequence of primaeval forest, secondary forest, wasteland, non irrigated farmland and cultivated farmland. There is only 541.9x10^3 in primeval forest, up to 5,984.2x10^3 in vegetable farmland. There are 749.5x10^3, and 5 genera in paddy field. But the diversity of actinomycetes is a more or less opposite sequence. Eight genera have been found in primaeval forests, 7 genera in secondary forests and 5 to 6 genera in cultivated field. The counts of Streptomyces strains make up about 90% of all actinomycetes in most soils and only 73% in paddy fields. Table 4. Actinomycete population of primaeval forests in Yunnan (10^3 cfu/g dry soil)
Genus I II IV X XI XII XII ---------------------------------------------------------- Streptomyces 325.9 555.9 188.5 22.2 1952.1 353.8 84.4 (%) 84 93 91 78 98 81 59 Chainia 0.7 0.1 3.8 Actinosporangium 1.4 Strepto- verticillium 3.0 Micromonospora 12.7 20.6 1.7 1.1 15.0 32.0 11.7 Actinoplanes 5.3 1.1 0.7 Strepto- sporangium 0.5 0.6 3.6 3.8 Actinomadura 1.4 7.3 0.8 1.2 8.5 7.2 7.8 Microbispora 0.6 10.6 3.8 Microtetraspora 0.6 10.6 3.8 Micropolyspora 0.6 Pseudonocardia 1.9 Saccharo- polyspora 19.0 3.6 2.6 6.4 7.1 3.8 Nocardia 16.0 7.1 5.6 1.3 12.1 10.1 19.1 Rhodococcus 7.3 5.7 Mycobacterium 0.3 Non-identified 1.4 4.4 2.5 Total 388.2 594.7 207.8 28.5 1996.2 435.6 142.0 No. of genera 9 7 12 5 7 8 9 Table 5. Actinomycete population of secondary forest in Yunnan (10^3 cfu/g dry soil)
Genus I II III IV V VI* --------------------------------------------------------- Streptomyces 309.8 370.2 782.9 521.0 259.2 544.0 (%) 85 91 91 96 94 62 Chainia 12.0 Strepto- verticillium 0.03 Actinosporangium 2.1 Micromonospora 12.7 12.1 16.5 5.0 12.0 59.0 Actinoplanes 4.0 5.0 2.0 12.0 Ampullariella 24.0 Dactylosporangium 1.2 Streptosporangium 0.1 1.2 29.0 Actinomadura 1.5 5.0 18.5 0.6 0.02 71.0 Microbispora Microtetraspora Saccharomonospora Saccharopolyspora 5.3 6.2 Nocardia 12.7 12.1 10.3 1.2 2.0 118.0 Promicromonospora 12.0 Rhodococcus 17.3 9.3 Non-identified 2.7 20.6 8.4 Total 366.1 408.7 857.1 543.6 275.2 881.0 No.of genera 8 5 6 7 6 9 Table 5 continued Genus VIII IX XI XII XIII ----------------------------------------------------- Streptomyces 563.2 488.7 1529.6 566.4 363.2 (%) 98 98 98 82 78 Chainia 3.5 Strepto- verticillium Actinosporangium 1.2 1.2 Micromonospora 1.2 4.4 11.7 3.5 28.8 Actinoplanes 3.5 Ampullariella Dactylosporangium 3.5 Streptosporangium 2.3 10.5 7.2 Actinomadura 1.1 7.2 10.7 17.6 Microbispora 17.8 Microtetraspora 18.0 7.2 Saccharomonospora 3.6 3.6 Saccharopolyspora 5.8 4.2 10.7 10.5 3.4 Nocardia 1.1 10.7 17.6 21.0 Promicromonospora Rhodococcus Non-identified 4.0 7.0 Total 574.8 503.6 1568.7 694.1 466.2 No.of genera 6 5 7 10 8 * West Mountain in Kunming Table 6. Actinomycete population of wasteland in Yunnan (10^3 cfu/g dry soil)
Genus I II III VI* VII ----------------------------------------------------- Streptomyces 403.0 860.0 488.0 369.0 1121.2 (%) 83 98 87 80 98 Actinosporangium Streptoverticillium 10.0 Micromonospora 38.0 4.0 25.0 36.0 7.8 Actinoplanes 4.0 12.0 Dactylosporangium 8.0 Streptosporangium 2.0 Actinomadura 2.0 2.0 12.0 36.0 32.1 Microbispora Microtetraspora Micropolyspora 2.0 Saccharomonospora Saccharopolyspora 12.0 1.0 Nocardia 14.0 20.0 Rhodococcus 6.0 1.0 Non-identified 5.0 Total 483.0 876.0 560.0 455.0 1140.0 No. of genera 6 5 8 4 4 Table 6 continued Genus VIII XI XII XIII ------------------------------------------------ Streptomyces 1038.6 1487.2 669.3 925.5 (%) 99 97 86 83 Actinosporangium 3.6 Streptoverticillium Micromonospora 7.2 3.4 46.1 98.8 Actinoplanes Dactylosporangium 6.9 Streptosporangium 3.4 7.2 3.5 Actinomadura 2.1 10.4 29.5 8.0 Microbispora 3.6 Microtetraspora 11.5 3.4 Micropolyspora Saccharomonospora 3.5 Saccharopolyspora 2.1 17.4 Nocardia 1.1 10.4 17.9 59.3 Rhodococcus Non-identified 10.4 Total 1051.1 1512.2 781.5 1149.9 No. of genera 5 6 7 9 * West Mountain in Kunming Table 7. Actinomycete population of non-irrigated farmland in Yunnan (10^3 cfu/g dry soil)
Genus I II II VIII XII XIII ----------------------------------------------------------- Streptomyces 439.8 1560.0 589.4 1625.4 692.8 854.1 (%) 92 99 85 99 90 93 Micromonospora 21.0 8.0 44.7 20.4 13.3 Actinoplanes 1.0 Streptosporangium 0.2 3.4 3.3 Actinomadura 1.0 4.0 27.0 4.1 17.0 3.3 Microtetraspora 6.9 Saccharopolyspora 2.0 9.4 10.4 6.8 3.3 Nocardia 13.0 10.4 4.2 17.1 40.3 Rhodococcus 1.0 Non-identified 3.4 10.1 Total 478.8 1572.2 691.3 1644.1 767.8 917.7 No. of genera 7 4 5 4 7 6 Table 8. Actinomycete population of vegetable farmland in Yunnan (10^3 cfu/g dry soil)
Genus III VI VIII ------------------------------------------- Streptomyces 2361.1 13883.0 861.6 (%) 75 86 99.8 Chainia Actinosporangium Streptoverticillium Micromonospora 160.3 677.0 2.1 Actinoplanes 113.0 Actinomadura 106.8 451.0 Microbispora Microtetraspora Saccharomonospora Saccharopolyspora 202.9 120.0 Nocardia 213.6 564.0 Rhodococcus 107.0 Promicromonospora 113.0 Non-identified Total 3151.7 15911.0 863.7 No. of genera 6 7 2 Table 8 continued Genus XI XII XIII ------------------------------------------- Streptomyces 11122.7 2179.4 1162.9 (%) 90 95 88 Chainia 3.5 Actinosporangium 36.3 3.4 Streptoverticillium 3.4 Micromonospora 46.0 57.9 Actinoplanes Actinomadura 36.3 24.6 34.2 Microbispora 36.3 3.4 Microtetraspora 6.9 6.8 Saccharomonospora 3.4 Saccharopolyspora 737.0 10.6 3.4 Nocardia 396.2 10.7 47.7 Rhodococcus Promicromonospora Non-identified 3.4 Total 12364.8 2291.7 1322.2 No. of genera 6 8 10 Table 9. Actinomycete population of paddy fields (10^3 cfu/g dry soil)
Genus I II III VI XI XIII ------------------------------------------------------------ Streptomyces 296.0 732.0 418.8 467.0 12976.0 828.9 (%) 71 73 71 67 92 81 Actinosporangium 4.0 0.2 Micromonospora 64.0 12.6 94.0 466.0 98.0 Streptosporangium 0.3 Actinomadura 59.3 Microbispora 5.2 Microtetraspora 10.4 Saccharopolyspora 10.0 50.0 94.3 34.0 466.0 5.2 Nocardia 10.0 72.0 18.9 110.0 266.0 66.9 Rhodococcus 34.0 71.8 22.0 Non-identified 5.2 Total 418.0 998.2 586.7 725.0 14174.0 1019.8 No. of genera 6 8 4 4 4 6 Table 10. Composition of actinomycetes in soil with different vegetation in Yunnan
Vegetational Number of Percentage Number of genera
actinomycetes of
type (10^3/g dry wt) streptomycetes Total Average
--------------------------------------------------------------
Primaeval
forest 541.9 83 15 8.1
Secondary
forest 649.0 89 17 7.0
Wasteland 889.9 90 15 6.0
Non-irrigated
farmland 1012.0 96 9 5.5
Vegetable
farmland 5984.2 89 14 6.5
Paddy fields 749.5 73 10 5.6
Characteristics of the Population of Soil Actinomycetes in Yunnan. The results suggest that the population of soil actinomycetes in Yunnan has several characteristics. 1. Twenty-two genera of Actinomycetales have been isolated from soil samples taken from 12 areas of Yunnan. For example Liu et al. (1984b, c) found the genus "Actinoalloteichus" and strains of Nocardiopsis; Zhang et al. (1984) found the genus "Streptomycoides" and Jiang et al. (1984) found a strain of Amorphosporangium. So a wide range of genera of actinomycetes have been detected in the soils of Yunnan. Application of improved isolation procedures may detect other novel useful taxa. 2. Actinomycete populations detected in soils under various climatic and vegetational conditions showed some quantitative and qualitative differences. Diversity of actinomycete was greatest in forest soils, 16 or 17-genera being isolated respectively from the primaeval or secondary forest. 3. Streptomyces strains comprised 91% overall isolates from all samples. The drier, poorer soil and the cooler climate, the higher the percentage of Streptomyces. 4. Micromonospora, Actinomadura and Nocardia were usually isolated at a frequency of 70%. 5. The upper limit for occurrence of thermophilic actinomycetes is 3,500 m above sea level in Yunnan. No thermophilic actinomycetes were found at a higher altitude (Jiang et al., 1988). Acknowledgments. The authors thank Professors H.A. and M.P. Lechevalier for their help in preparing this manuscript. The work was supported by National Natural Science Foundation of China. References Jiang, C. & L.Xu (1985). Isolation methods for research on population of soil actinomycetes. Microbiology, 12:218- 220 Jiang, C. & L.Xu (1985-1986). Actinomycetes of lakes on the Yunnan Plateau. The Actinomycetes, 19:211-222 Jiang, C., L.Xu & G.Guo (1988). The actinomycetes in the frigid mountains. Acta Biologica Sinica, 28:198-205 Jiang, Z. & X.Yan (1984). A new species of Amorphosporangium. Acta Microbiologica Sinica, 24: 129-133 Liu, L., Y.Yu & J. Zhang (1984a). The diversion of vertical vegetation zone in Hengduanshan. Acta Botanica Yunnanica, 6' 205-216 Liu, Z., Y.Zhang & X.Yan (1984b). A new genus of the order Actinomycetales. Acta Microbiologica Sinica, 24:295- 298 Liu, Z., Y.Zhang & X.Yan (1984c). A new species of Nocardiopsis. Acta Microbiologica Sinica, 24:26-29 Nonomura, H. & M.Hayakawa (1988). New methods for selective isolation of soil actinomycetes. In: Y.Okami, T.Beppu & H.Ogawara (eds.) Biology of Actinomycetes '88. Japan Sci. Sec.Press, Tokyo, pp. 288-293 Xu, Z., G.Tao, P.Yu & Y.Wang (1985). Search on vegetation of Yuanjiang River valley in last five hundreds years. Acta Botanica Yunnanica, 7:403-412 Zhang, G., G.Xing & X.Yan (1984). A new genus of the Family Streptomycetaceae. Acta Microbiologica Sinica, 24: 189- 194. Copyright 1990 C.E.T.A., The International Centre for Theoretical and Applied Ecology, Gorizia
|
| |||||||||
