A study of the diversity of cultivable seed-borne bacteria in Poa pratensis and the growth-promoting characteristics of 18 bacterial strains

doi:10.11686/cyxb2024086

Abstract

Abstract:

This study investigated the diversity of cultivable seed-borne bacteria of Poa pratensis to identify strains with superior plant growth-promoting properties. The cultivable seed-borne bacteria of three varieties of P. pratensis were isolated by the dilution plate method and 30 bacterial isolates were obtained. Through 16S rRNA sequence analysis， 18 representative isolates with different morphological characteristics were identified and phylogenetic trees were constructed. It was found that the isolated cultivable seed-borne bacteria so identified belonged to the phyla Firmicutes， Actinobacteria and Proteobacteria， and included six genera， Bacillus， Paenibacillus， Pseudomonas， Curtobacterium， Stenotrophomonas and Erwinia. Among them， Bacillus is the common genus of three varieties. The nitrogen fixation， indole-3-acetic acid-producing， phosphorus solubilization and extracellular enzyme （protease， cellulase and amylase） production of the 18 bacterial taxa were determined and it was found that strains designated BM8 and KTJ14 possessed all three of the above functions. In addition， the biofilm formation ability and swimming motility of the strains were determined by crystal violet staining and swimming medium， and the correlation between these two traits and the growth-promoting function of isolated taxa is discussed. A strain designated KTJ16 had the strongest biofilm formation ability， and the swimming motility of taxa designated SW5 and KTJ18 was significantly stronger than that of other taxa. Based on multiple characteristics， the strains with superior growth-promoting characteristics were determined to be BM8， SW5， KTJ14， KTJ16 and KTJ18.

Key words: nitrogen fixation, phosphorus solubilizing, IAA-producing, producing extracellular enzymes, biofilm, swimming motility

Jin-jing XIE, Shao-wei ZHU, Rong HUANG, Jie YANG, Xuan HOU, Zhen-fen ZHANG. A study of the diversity of cultivable seed-borne bacteria in Poa pratensis and the growth-promoting characteristics of 18 bacterial strains[J]. Acta Prataculturae Sinica, 2024, 33(12): 134-146.

Figures/Tables 7

References 53

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菌株 Strain	数量Number （CFU·g^-1）	属水平分类 Genus level classification	登录号 Accession
BM2	1.95×10⁵a	短小杆菌属Curtobacterium sp.	PP094560
BM4	2.33×10⁴def	假单胞菌属Pseudomonas sp.	PP094561
BM8	3.33×10³f	芽孢杆菌属Bacillus sp.	PP094562
BM9	5.33×10³ef	芽孢杆菌属Bacillus sp.	PP094563
BM10	2.47×10⁴de	短小杆菌属Curtobacterium sp.	PP094564
BM12	1.46×10⁵b	假单胞菌属Pseudomonas sp.	PP094565
KTJ3	2.27×10⁴def	类芽孢杆菌属Paenibacillus sp.	PP094566
KTJ5	7.67×10⁴c	欧文氏菌属Erwinia sp.	PP094567
KTJ9	1.07×10⁴def	芽孢杆菌属Bacillus sp.	PP094568
KTJ14	2.13×10⁴def	芽孢杆菌属Bacillus sp.	PP094569
KTJ16	8.67×10³def	芽孢杆菌属Bacillus sp.	PP094570
KTJ18	2.67×10³f	芽孢杆菌属Bacillus sp.	PP094571
SW1	3.47×10⁴d	芽孢杆菌属Bacillus sp.	PP094572
SW3	6.67×10³ef	芽孢杆菌属Bacillus sp.	PP094574
SW5	4.67×10³ef	芽孢杆菌属Bacillus sp.	PP094575
SW9	3.33×10³f	芽孢杆菌属Bacillus sp.	PP094576
SW10	1.33×10⁴def	寡养单胞菌属Stenotrophomonas sp.	PP094573
SW11	5.93×10⁴c	类芽孢杆菌属Paenibacillus sp.	PP094577

菌株 Strain	数量Number （CFU·g^-1）	属水平分类 Genus level classification	登录号 Accession
BM2	1.95×10⁵a	短小杆菌属Curtobacterium sp.	PP094560
BM4	2.33×10⁴def	假单胞菌属Pseudomonas sp.	PP094561
BM8	3.33×10³f	芽孢杆菌属Bacillus sp.	PP094562
BM9	5.33×10³ef	芽孢杆菌属Bacillus sp.	PP094563
BM10	2.47×10⁴de	短小杆菌属Curtobacterium sp.	PP094564
BM12	1.46×10⁵b	假单胞菌属Pseudomonas sp.	PP094565
KTJ3	2.27×10⁴def	类芽孢杆菌属Paenibacillus sp.	PP094566
KTJ5	7.67×10⁴c	欧文氏菌属Erwinia sp.	PP094567
KTJ9	1.07×10⁴def	芽孢杆菌属Bacillus sp.	PP094568
KTJ14	2.13×10⁴def	芽孢杆菌属Bacillus sp.	PP094569
KTJ16	8.67×10³def	芽孢杆菌属Bacillus sp.	PP094570
KTJ18	2.67×10³f	芽孢杆菌属Bacillus sp.	PP094571
SW1	3.47×10⁴d	芽孢杆菌属Bacillus sp.	PP094572
SW3	6.67×10³ef	芽孢杆菌属Bacillus sp.	PP094574
SW5	4.67×10³ef	芽孢杆菌属Bacillus sp.	PP094575
SW9	3.33×10³f	芽孢杆菌属Bacillus sp.	PP094576
SW10	1.33×10⁴def	寡养单胞菌属Stenotrophomonas sp.	PP094573
SW11	5.93×10⁴c	类芽孢杆菌属Paenibacillus sp.	PP094577

菌株 Strain	固氮 NF	产吲哚-3-乙酸 IAAP （μg·mL^-1）	溶磷 Phosphorus solubilizing （D/d ）		产胞外酶 Producing extracellular enzymes （D/d ）
菌株 Strain	固氮 NF	产吲哚-3-乙酸 IAAP （μg·mL^-1）	有机磷 Organic phosphorus	无机磷 Inorganic phosphorus	蛋白酶 Protease	纤维素酶 Cellulase	淀粉酶 Amylase
BM2	＋	－	－	－	2.34±0.09c	－	－
BM4	＋	－	－	1.20±0.024a	－	－	－
BM8	＋	19.21±0.16a	－	－	1.80±0.02de	－	－
BM9	＋	－	－	－	2.41±0.09bc	3.05±0.10cd	2.42±0.05c
BM10	＋	－	－	－	2.63±0.02ab	3.78±0.11b	－
BM12	＋	－	－	1.15±0.023a	－	－	－
KTJ3	＋	－	－	－	－	3.38±0.07c	2.93±0.07b
KTJ5	＋	－	－	－	－	－	－
KTJ9	＋	－	－	－	2.04±0.02d	2.58±0.06e	1.51±0.02d
KTJ14	＋	18.42±0.12b	－	－	1.73±0.04ef	－	－
KTJ16	－	18.46±0.23b	－	－	1.30±0.02g	－	－
KTJ18	＋	－	－	－	1.79±0.05de	3.07±0.03cd	－
SW1	－	－	－	－	1.50±0.02fg	－	1.37±0.02d
SW3	－	－	－	－	1.29±0.01g	2.87±0.10de	2.27±0.04c
SW5	＋	－	－	－	2.30±0.08c	2.96±0.07de	－
SW9	＋	－	－	－	1.87±0.02de	－	－
SW10	－	－	－	－	2.75±0.13a	－	－
SW11	＋	－	－	－	－	4.62±0.12a	3.34±0.08a

菌株 Strain	固氮 NF	产吲哚-3-乙酸 IAAP （μg·mL^-1）	溶磷 Phosphorus solubilizing （D/d ）		产胞外酶 Producing extracellular enzymes （D/d ）
菌株 Strain	固氮 NF	产吲哚-3-乙酸 IAAP （μg·mL^-1）	有机磷 Organic phosphorus	无机磷 Inorganic phosphorus	蛋白酶 Protease	纤维素酶 Cellulase	淀粉酶 Amylase
BM2	＋	－	－	－	2.34±0.09c	－	－
BM4	＋	－	－	1.20±0.024a	－	－	－
BM8	＋	19.21±0.16a	－	－	1.80±0.02de	－	－
BM9	＋	－	－	－	2.41±0.09bc	3.05±0.10cd	2.42±0.05c
BM10	＋	－	－	－	2.63±0.02ab	3.78±0.11b	－
BM12	＋	－	－	1.15±0.023a	－	－	－
KTJ3	＋	－	－	－	－	3.38±0.07c	2.93±0.07b
KTJ5	＋	－	－	－	－	－	－
KTJ9	＋	－	－	－	2.04±0.02d	2.58±0.06e	1.51±0.02d
KTJ14	＋	18.42±0.12b	－	－	1.73±0.04ef	－	－
KTJ16	－	18.46±0.23b	－	－	1.30±0.02g	－	－
KTJ18	＋	－	－	－	1.79±0.05de	3.07±0.03cd	－
SW1	－	－	－	－	1.50±0.02fg	－	1.37±0.02d
SW3	－	－	－	－	1.29±0.01g	2.87±0.10de	2.27±0.04c
SW5	＋	－	－	－	2.30±0.08c	2.96±0.07de	－
SW9	＋	－	－	－	1.87±0.02de	－	－
SW10	－	－	－	－	2.75±0.13a	－	－
SW11	＋	－	－	－	－	4.62±0.12a	3.34±0.08a

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