植物生态学报 ›› 2019, Vol. 43 ›› Issue (6): 543-556.doi: 10.17521/cjpe.2019.0045

• 研究论文 • 上一篇    

入侵植物加拿大一枝黄花根际解钾菌多样性及解钾活性

闫雅楠1,2,叶小齐1,*(),吴明1,闫明2,张昕丽1   

  1. 1 中国林业科学研究院亚热带林业研究所, 杭州湾湿地生态系统定位观测研究站, 浙江富阳 311400
    2 山西师范大学生命科学学院, 山西临汾 041000
  • 收稿日期:2019-02-28 修回日期:2019-05-29 出版日期:2019-06-20 发布日期:2019-09-30
  • 通讯作者: 叶小齐 E-mail:mengxqi@126.com
  • 基金资助:
    国家自然科学基金(31770578)

Diversity and potassium-solubilizing activity of rhizosphere potassium-solubilizing bacteria of invasive Solidago canadensis

YAN Ya-Nan1,2,YE Xiao-Qi1,*(),WU Ming1,YAN Ming2,ZHANG Xin-Li1   

  1. 1 Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Wetland Ecosystem Research Station of Hangzhou Bay, Fuyang, Zhejiang 311400, China
    2 School of Life Science, Shanxi Normal University, Linfen, Shanxi 041000, China
  • Received:2019-02-28 Revised:2019-05-29 Online:2019-06-20 Published:2019-09-30
  • Contact: YE Xiao-Qi E-mail:mengxqi@126.com
  • Supported by:
    Supported by the National Natural Science Foundation of China(31770578)

摘要:

入侵植物加拿大一枝黄花(Solidago canadensis)具有较强的钾(K)富集能力, 这可能和其对土壤微生物群落的改变有关。根际解钾菌能够将植物难以利用的矿物态钾转化为植物可以利用的可溶性钾, 而加拿大一枝黄花如何影响根际解钾菌多样性和解钾活性尚未明了。该研究以浙江省杭州湾湿地围垦区内自然生长的加拿大一枝黄花和其伴生本地植物白茅(Imperata cylindrica)为研究对象, 比较了加拿大一枝黄花和白茅体内及土壤中的钾含量水平, 钾供给水平对生物量积累的影响, 以及根际解钾菌的数量、多样性和解钾活性的差异。结果表明, 加拿大一枝黄花茎、叶中的钾含量均显著高于白茅, 分别是白茅的1.59和7.33倍; 加拿大一枝黄花和白茅的土壤全钾含量差异不显著, 速效钾含量在0-10 cm土层中差异显著、在10-20 cm土层中差异不显著。随着钾供应水平提高, 加拿大一枝黄花和白茅的生物量均显著增加。利用解钾培养基计数培养后发现, 加拿大一枝黄花根际解钾菌的数量是白茅的3.51倍。分离培养后将出现解钾圈的菌株进行鉴定, 利用解钾液体培养实验测定其解钾量, 发现从加拿大一枝黄花根际土中分离得到的15个解钾菌株中, 有9个具有高效解钾能力, 其处理液中K +含量较空白对照高出85.11%-192.54%, 其中菌株H2-20解钾能力最强, 解钾量为10.657 mg·L -1。加拿大一枝黄花根际解钾菌解钾作用显著高于白茅。经16S rDNA鉴定发现, 加拿大一枝黄花15个根际解钾菌株分属11个属, 其中有6个属已经被报道证实具有明显解钾能力。这些结果表明加拿大一枝黄花根际解钾菌数量较为丰富, 且大多具有较高解钾活性, 可能对其钾富集具有重要贡献。

关键词: 入侵植物, 根际解钾菌, 解钾能力, 入侵机制, 系统发育树

Abstract:
Aims Solidago canadensis, an invasive herbaceous species, has a strong capacity of potassium enrichment, that may relate to its influence on soil microbial community. Rhizosphere potassium-soluble bacteria can convert mineral potassium into soluble forms being able to be used by plants. It is not known how invasion of S. canadensis may affect diversity and potassium-solubilizing activity of the potassium-solubilizing bacteria. Methods We compared S. canadensis and its coexisting native plant Imperata cylindrica in the reclaimed Hangzhou Bay wetland, Zhejiang Province. We compared the potassium contents of soil and the plant tissues of S. canadensis and Imperata cylindrica which coexists with the invasive species, the effect of potassium supply level on biomass accumulation of plants, and the quantity, diversity and potassium-soluble activity of the rhizosphere potassium-solubilizing bacteria. Important findings The potassium contents in stem and leaf of S. canadensis were significantly higher (1.59 and 7.33 times respectively) than that of I. cylindrica, the contents of available potassium in the 0-10 cm soil layer where the two species grew were significantly different, but not in the 10-20 cm soil layer. Potassium application experiments showed significant biomass increase in both S. canadensis and I. cylindrica, and tissue potassium concentrations as well. Potassium-dissolving medium culture results showed that the number of potassium-‌solubilizing bacteria of S. canadensis rhizosphere was 2.51 times higher than that of I. cylindrica. The strains with potassium-dissolving rings were identified, and the amount of released potassium was determined. Among the 15 strains of potassium-solubilizing bacteria isolated from the rhizosphere soil of S. canadensis, nine efficiently dissolved potassium, and the content of K + in the treatment solution was 85.11%-192.54% higher than that in the control. Strain H2-20 had the strongest ability with the dissolved K + of 10.657 mg·L -1. The potassium- solubilizing effect of rhizosphere potassium-solubilizing bacteria of S. canadensis was significantly higher than that of I. cylindrica. According to 16S rDNA identification, the 15 strains of bacteria associated with S. canadensis were of 11 genera, and 6 of them had been reported to have the potassium-solubilizing ability. Our results suggest that potassium-solubilizing bacteria in the rhizosphere of S. canadensis is abundant, and may play an important role in potassium enrichment.

Key words: invasive plant, rhizosphere potassium-solubilizing bacteria, potassium capacity, intrusion mechanism, phylogenetic tree