title: Cold Stress Tolerance in Psychrotolerant Soil Bacteria and Their Conferred Chilling Resistance in Tomato (Solanum lycopersicum Mill.) under Low Temperatures.
abstract: The present work aimed to study the culturable diversity of psychrotolerant bacteria persistent in soil under overwintering conditions, evaluate their ability to sustain plant growth and alleviate chilling stress in tomato. Psychrotolerant bacteria were isolated from agricultural field soil samples colleced during winter and then used to study chilling stress alleviation in tomato plants (Solanum lycopersicum cv Mill). Selective isolation after enrichment at 5°C yielded 40 bacterial isolates. Phylogenetic studies indicated their distribution in genera Arthrobacter, Flavimonas, Flavobacterium, Massilia, Pedobacter and Pseudomonas. Strains OS211, OB146, OB155 and OS261 consistently improved germination and plant growth when a chilling stress of 15°C was imposed and therefore were selected for pot experiments. Tomato plants treated with the selected four isolates exhibited significant tolerance to chilling as observed through reduction in membrane damage and activation of antioxidant enzymes along with proline synthesis in the leaves when exposed to chilling temperature conditions (15°C). Psychrotolerant physiology of the isolated bacteria combined with their ability to improve germination, plant growth and induce antioxidant capacity in tomato plants can be employed to protect plants against chilling stress.
authors: Department of Environmental and Biological Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors: Parthiban
authors: P
authors: Subramanian
authors: Department of Environmental and Biological Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors: Kiyoon
authors: K
authors: Kim
authors: Department of Environmental and Biological Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors: Ramasamy
authors: R
authors: Krishnamoorthy
authors: School of Biosciences and Technology, VIT University, Vellore 632014, Tamil Nadu, India.
authors: Anbazhagan
authors: A
authors: Mageswari
authors: Department of Environmental and Biological Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors: Gopal
authors: G
authors: Selvakumar
authors: Department of Environmental and Biological Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors: Tongmin
authors: T
authors: Sa
mesh_terms: D001419:Bacteria / Q000254:growth & development*; D003080:Cold Temperature; D058639:Cold-Shock Response / Q000502:physiology*; D018525:Germination / Q000502:physiology*; D018551:Solanum lycopersicum / Q000254:growth & development / Q000382:microbiology; D012621:Seasons; D012988:Soil Microbiology