Author：Chun-Tse Chang¹, Wei-An Lai², Chiu-Chung Yang³, and Fo-Ting Shen^4,*

Abstrct：

    The present study was undertaken to study the colonizing behavior of phosphate solubilizing bacteria toward crops with high phosphorus demand. Motility, IAA and ACC deaminase producing abilities of phosphate solubilizing bacteria were screened first to obtain superior candidates. Bacterial inoculations were performed in seed bioassay and flask experiment. Considered for plant growth and bacterial colonization, the compatibilities of phosphate solubilizing bacteria toward cabbage, spinach and tomato were evaluated. The niche fitness of bacteria in soils will also be demonstrated in pot experiment. Out of the tested 35 strains were subjected to seed bioassay, and 8, 8, 3 strains were beneficial to seed germination of cabbage, tomato and spinach, respectively. Among them, 2 strains increased dry weight of above part of cabbage, 4 strains increased dry weight of above part of tomato, and 3 strains increased dry weight of above part of spinach. After 30 days of cultivation, inoculated strains still survived on root surface, as demonstrated using BOX-PCR fingerprinting of re-isolated strains and fluorescence in situ hybridization technique with EUB338 probe. Pot experiments showed that Bacillus marisflavi and Pseudoarthrobacter niigatensis can promote growth of cabbage, Brevundimonas albigilva and Gordonia hongkongensis can promote growth of tomato while Bacillus xiamenensis and Paraburkholderia sacchari can promote growth of spinach.

Keywords: Microbial fertilizer, phosphate solubilizing bacteria, cabbage, tomato, spinach, gene fluorescent probe.

* Corresponding author, e-mail: ftshen@dragon.nchu.edu.tw
¹ Researcher Assistant, Department of Soil and Environmental Science, National Chung Hsing University, Taichung, Taiwan, ROC.
² Postdoctoral Researcher, Department of Soil and Environmental Science, National Chung Hsing University, Taichung, Taiwan, ROC.
³ Professor, Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung, Taiwan, ROC. Academician of the Academia Sinica.
⁴ Associate Professor, Department of Soil and Environmental Science, National Chung Hsing University, Taichung, Taiwan, ROC.