Full Length Research Paper

Isolation, quantity distribution and characterization of endophytic microorganisms within sugar beet

Yingwu Shi^1,2, Kai Lou¹* and Chun Li²

¹Institute of Microbiology, Xinjiang Academy of Agriculture Science 830091 Urumqi Xinjiang, China.

²IAgriculture college of Shihezi University/Green Chemical Processes Key laboratory in Xinjiang BINGTUAN , 832003 Shihezi, Xinjiang, China.

*Corresponding author. E-mail: loukai02@mail.tsinghua.edu.cn.

Accepted 23 January, 2009

The present investigation was undertaken in order to document the spectrum of endophytes colonizing healthy leaves of sugar beet cultivars in Xinjiang Province (China) and to determine the degree of colonization at three growth stages. From the 360 sugar beet leaf and root segments incubated, 221 bacterial isolates, 34 fungal isolates and 5 actinomycete isolates were obtained. Of all the isolates, 7 bacterial species and 6 fungal species were identified. The actinomycete isolates were characterized as Streptomyces griseofuscus and Streptomyces globisporus. There were significant differences between microorganisms, stages of growth, and stages of microorganism interaction. The number of microorganisms isolated increased during the growth period of the sugar beet. At the same time, the number of microorganisms affecting different parts of the sugar beet tissue was quite different. The greatest number of microorganisms was found in the secondary root emergence zone of the sugar beet tissue. Endophytic microorganisms in sugar beet promote growth and increase the yield of the beet.

Key words: Isolation, quantity distribution, characterization, endophytic microorganisms, sugar beet.