Characterization and plant growth-promoting effects of halotolerant bacteria under salt stress

• Main Authors: Po-Ting Yeh, 葉柏廷
• Other Authors: Chiu-Chung Young
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/56841745226107169503

碩士 === 國立中興大學 === 土壤環境科學系所 === 104 === The acumulation of salinity in soil is one of the major problems in agricultural production, and therefore the mean to apply plant growth promoting bacteria (PGPB) to improve crop growth in salty soil is an important issue now. In this research, eight halotolerant strains, include Algoriphagus olei BCRC 17886, Bacillus sp CC-CCM 15-5, Brachybacterium sp CC-LVL15-1, Erythrobacter sp CC-CCM15-2Y, Leucobacter komagatae DSM 8803, Leucobacter tardus DSM 19811, Leucobacter chironomi DSM 19883 and Rhizobium sp. CC-CCM15-2W, of which the former 5 strains were isolated from Professor Young’s Lab and the latter 3 strains were purchased from cell culture center, were chosen and identified. Furthermore, The PGP traits under salt stress of above mentioned strains showed that CC-CCM 15-2W had N fixation, P solubilization and 1-Aminocyclopropane-1-Carboxylate (ACC) utilizing potential; BCRC 17886 had N fixation, ACC utilizing potential and IAA production. Seed germination bioassay and pot experiment were conducted by using Chinese kale and Water spinach to test the impact of bacteria inoculation on crop growth in 0.88% NaCl saline stress. Seed germination bioassay data showed that CC-CCM 15-2W( increased by 26% and 30% in epicotyls and radicle of Chinese kale, and by 29% in radicle of Water spinach), CC-CCM 15-5 and BCRC 17886 ( radicle of Water spinach was increased by 32% and 34%, respectively); Pot experiment under irrigation of saline water (0.88% NaCl) data demonstrated that CC-CCM 15-2W and half-dose chemical fertilizer + CC-CCM 15-2W improved the shoot biomass of Chinese kale by 92% and 35%, respectively; and half- dose chemical fertilizer + BCRC 17886 and half-dose fertilizer + CC-CCM 15-2W promoted Chinese kale shoot biomass by 45% and 48%, respectively. It is northworthy that under 0.88% NaCl solution+1/2 chemical fertilizer condition, individual inoculation with strains CC-CCM15-5, CC-CCM15-2W and BCRC 17886 can decrease the salinity in rhizosphere of water spinach by 59.6, 66.0 and 66.0%, respectively; and inoculation with CC-CCM15-2W can decrease the salinity of Chinese Kale rhizosphere by 26.9%. Therefore, this study has successfully evidenced the efficiency of halotolerant bacteria as inocula and mineral fertilizer on crop growth under saline stress, also it can be the reference method for screening and isolation of halotolerant bacteria for using as biofertilizer in salt stress.