title: Effect of Poly(γ-glutamic acid) on the Physiological Responses and Calcium Signaling of Rape Seedlings (Brassica napus L.) under Cold Stress.
abstract: Cold stress adversely affects plant growth and development. Poly(γ-glutamic acid) (γ-PGA) is a potential plant growth regulator that may be an effective cryoprotectant that prevents crops from damage during cold weather. In this study, the effects of γ-PGA on the physiological responses of rape seedlings subject to cold stress were investigated using hydroponic experiments. We determined that the malondialdehyde content was decreased by 33.4% and the proline content was increased by 62.5% by γ-PGA after 144 h under cold stress. Antioxidant enzymes activities were also evidently enhanced after treatment with γ-PGA. These responses counteracted increases in the fresh weight and chlorophyll content of rape seedlings, which increased by 24.5 and 50.9%, respectively, after 144 h, which meant that growth inhibition caused by cold was mitigated by γ-PGA. Our results also showed that γ-PGA also regulated Ca(2+) concentrations in the cytoplasm and calcium-dependent protein kinases, which are associated with cold resistance. In conclusion, we suggest that the Ca(2+)/CPKs signal pathway is involved in the γ-PGA-mediated enhancement of cold resistance in rape seedlings.
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lei
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Zongqi
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Nanjing Shineking Biological Technology Company, Ltd., Nanjing 210000, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ding
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Bao
authors.initials: B
authors.lastname: Tang
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Huashan
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Feng
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University , Nanjing 211816, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
mesh_terms: D029688:Brassica napus / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D003080:Cold Temperature; D008315:Malondialdehyde / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D011099:Polyglutamic Acid / Q000031:analogs & derivatives; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D010940:Plant Proteins; C511775:poly(gamma-glutamic acid); D002734:Chlorophyll; D011099:Polyglutamic Acid; D008315:Malondialdehyde; D002374:Catalase; D013482:Superoxide Dismutase; D002118:Calcium
keywords: Ca2+ fluctuation; Ca2+/CPKs signal pathway; antioxidant enzymes; cold stress; poly(γ-glutamic acid); proline