摘要
重庆及西南稻区水稻幼苗期倒春寒频发,常常导致秧苗生长迟缓,白化、烂秧等发生,制约了优质水稻安全生产和轻简化技术的应用。本研究以耐冷性较强的渝17S和对低温敏感的Y58S为材料,对比研究了3叶龄幼苗经4℃低温处理后,二者可溶性糖、海藻糖、脯氨酸、丙二醛和过氧化氢的含量,超氧化物歧化酶、过氧化氢酶和抗坏血酸过氧化物酶的活性,以及荧光定量PCR检测胁迫相关的9个基因的表达情况。结果表明:与Y58S相比,渝17S具有更强的苗期耐冷性,在低温胁迫下,其死苗率为7.5%,而Y58S死苗率高达96.7%;低温胁迫下2个品种叶片中丙二醛和H_(2)O_(2)含量均升高,但渝17S增幅较小;渝17S叶片中抗氧化酶(超氧化物歧化酶、过氧化氢酶和抗坏血酸过氧化物酶)活性,可溶性糖和海藻糖含量,以及OsCATB、OsSOD、OsAPx8,OsTPS1、OsTPP1、OsMKK6、OsMAPK3和OsICE1基因表达量均呈不同程度增加;2个品种叶片中脯氨酸含量和脯氨酸合成限速酶基因(OsP5CS)的表达量未见明显差异。初步认为,H_(2)O_(2)信号分子和海藻糖可以调控渝17S对低温胁迫的响应,从而增强其幼苗的抗寒性。
"Late spring coldness"negatively affects rice seedling establishment and leads to rice growth retardation,albinism and rotten in Chongqing and southwest China,which severely restricts the production of high-quality rice and the application of optimal cultivation technologies.To investigate the cold tolerance of the chilling-tolerant indica cultivar Yu17S and chilling-sensitive indica cultivar Y58S seedlings,different parameters including the contents of soluble sugar,trehalose,proline,MDA and H2O2,the activities of antioxidant enzyme(SOD,POD and CAT),and the relative expression of stress relative genes were deployed.If compared with Y58S with the dead seedlings rate of up to 96.7%,Yu17S represented 7.5%of the dead seedlings rate,suggesting a stronger cold tolerance at the seedling stage upon the low temperature stress.The contents of both H2O2 and MDA increased in both cultivars under the low temperature stress,whereas both values of Yu17S were lower than these of Y58S.In Yu17S,the CAT,SOD and APX activity,soluble sugar and trehalose content,as well as the transcripts of genes Os CATB,Os SOD,Os APx8,Os TPS1,Os TPP1,Os MKK6,Os MAPK3 and Os ICE1 have been observed to be significantly increased.No significant differences on the proline content and on the expression of OsP5CS that controls the proline biosynthesis in both cultivars were observed.It is possible that the H2O2 signal molecule and trehalose of Yu17S may respond to the low temperature stress at the seedling stage,thus resulting in an enhancement on cold resistance.
作者
潘晓雪
张现伟
李经勇
雷开荣
PAN Xiao-xue;ZHANG Xian-wei;LI Jing-yong;LEI Kai-rong(Biotechnology Research Center,Chongqing Academy of Agricultural Sciences/Chongqing Key Laboratory of Adversity Agriculture,Chongqing 401329;Chongqing Ratooning Rice Research Center,Chongqing Academy of Agricultural Sciences,Chongqing 402160)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2021年第1期205-213,共9页
Journal of Plant Genetic Resources
基金
重庆市农业科学院青年创新团队项目(NKY-2018QC04)。
关键词
水稻
低温胁迫
苗期
耐冷机制
rice
low temperature stress
seedling
cold-resistance mechanisms
