摘要
以2015年采自青藏高原高寒草地野生老芒麦为对象,研究了不同程度NaCl盐胁迫下激动素对老芒麦幼苗端粒酶活性及生理特性的影响,为土壤盐渍化地区的农业生产以及老芒麦人工草地改良提供科学依据。采用营养液砂培法,待幼苗生长至第3片叶抽出并刚展开时,对老芒麦幼苗进行不同浓度(0、50、100、150、200mmol·L^(-1))的NaCl盐胁迫处理168h,随后用不同浓度(0、5、10、20、30mg·L^(-1))的激动素叶面喷施处理240h并测定幼苗的端粒酶活性以及生理指标:叶绿素、游离脯氨酸(Pro)、丙二醛(MDA)、可溶性糖(SS)、可溶性蛋白(SP)含量。结果表明,随着盐胁迫的增强,端粒酶活性呈现出先上升后下降的趋势,在50mmol·L^(-1)的NaCl处理下,端粒酶活性达到最大值。当处理浓度大于50mmol·L^(-1)时,随着盐胁迫的进一步增强,端粒酶活性逐步减小,渗透调节物质游离脯氨酸、可溶性糖、可溶性蛋白含量均上升。可溶性糖在250mmol·L^(-1)盐浓度下增加量最显著(P<0.05),与对照相比增加了101.5%。0mmol·L^(-1)盐胁迫下经10mg·L^(-1)的激动素处理后,MDA含量下降64.9%。较高浓度激动素对盐胁迫的缓解效果显著(P<0.05),250mmol·L^(-1)盐胁迫下经20mg·L^(-1)激动素处理的植株,叶绿素含量较对照增加了17.3%,可溶性糖在100mmol·L^(-1)盐胁迫下经20mg·L^(-1)激动素处理,其含量较对照增加了165.6%。结果表明外源激动素对盐胁迫具有一定的缓解作用,适宜浓度的盐胁迫诱导了细胞端粒酶活性,高浓度盐胁迫可能造成了老芒麦细胞的氧化损伤,最终导致端粒酶活性下降。
A study has been undertaken to investigate the effects of kinetin on the telomerase activity and physiological characteristics of wild Elymus sibiricus seedlings under different levels of salt stress in order to provide a scientific basis for agricultural production in areas with severe soil salinization and the improvement of artificial grassland.Wild E.sibiricus were collected from Qinghai-Tibet Plateau alpine grassland in 2015 and used as test material in sand culture experiments.When the third leaf of the seedlings extracted and unfolded,the seedlings were treated with sodium chloride(NaCl)solution at different concentration levels(0,50,100,150,200 mmol·L-1)for 168 hours.The seedlings’leaves were then sprayed with kinetin solutions of different concentrations(0,5,10,20,30 mg·L-1)for 240 hours and measurements taken of telomerase activity and physiological parameters:chlorophyll,free proline(Pro),malondialdehyde(MDA),soluble sugar(SS),and soluble protein(SP)content.The results showed that with the increase of salt stress,telomerase activity firstly increased and then decreased,peaking under the 50 mmol·L-1 NaCl treatment.When NaCl concentrations were higher than 50 mmol·L-1,telomerase activity decreased and the content of free proline,soluble sugar and soluble protein increased with increasing salt stress,among which the SS increment(101.5%)of seedlings under 250 mmol·L-1 NaCl was significantly different from that of the control(P<0.05).Following spraying with 10 mg·L-1 kinetin,the MDA content of seedlings treated with 0 mmol·L-1 NaCl decreased by 64.9%.High concentrations of kinetin can significantly relieve the salt stress of seedlings(P<0.05),with chlorophyll content(under 250 mmol·L-1 NaCl stress)and SS content(under 100 mmol·L-1 NaCl stress)increasing by 17.3%and 165.6%respectively after spraying with 20 mg·L-1 kinetin.These results indicate that exogenous kinetin alleviates salt stress to some extent.Suitable NaCl concentrations induced telomerase activity,whereas high concentrations of NaCl
作者
孙守江
师尚礼
吴召林
何丽娟
金鑫
祁娟
SUN Shou-jiang;SHI Shang-li;WU Zhao-lin;HE Li-juan;JIN Xin;QI Juan(College of Grassland Science,Gansu Agricultural University,Key Laboratory of Grassland Ecosystem,Ministry of Education,Grassland Engineering Laboratory,China-US Center for Grazing Land Ecosystem Sustainability,Lanzhou 730070,China)
出处
《草业学报》
CSCD
北大核心
2018年第11期87-94,共8页
Acta Prataculturae Sinica
基金
国家自然科学基金地区基金(31660684)
公益性行业科研专项(201403048-8)
国家牧草产业技术体系(CARS-34)资助。
关键词
老芒麦
端粒酶活性
盐胁迫
生理特性
Elymus sibiricus
telomerase activity
salt stress
physiological characteristics
