Identification of a cold tolerant mutant in seashore paspalum (Paspalum vaginatum)
Identification of a cold tolerant mutant in seashore paspalum (Paspalum vaginatum)
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海滨雀稗（Paspalum vaginatum）耐寒突变体的鉴定
DOI：
10.1007/s11240-019-01734-z
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发表时间：
2019-11-11
影响因子：
3
通讯作者：
Guo, Zhenfei
中科院分区：
文献类型：
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作者：
Shi, Haifan;Huang, Risheng;Guo, Zhenfei
海滨雀稗（paspalum vaginatumSwartz）是一种常用的暖季草坪草，具有优异的耐盐性。低温是限制其生长和种植区域的主要非生物胁迫之一。建立了甲烷磺酸乙酯（EMS）诱导滨海雀稗胚性愈伤组织突变和耐冷性增强突变品系选育方案。胚性愈伤组织经0.8%的EMS处理5 h后，愈伤组织存活率约为50%，并用于海滨雀稗胚性愈伤组织的诱导突变。从1万多株再生植株中筛选出耐寒性增强的突变系A6。低温驯化7 d后，A6的TEL50（温度导致电解质泄漏50%）低于野生型（WT），成活率高于野生型（WT）。两种基因型的抗氧化防御系统均对低温有响应，在低温处理3天后，A6的CAT活性高于WT。在冷处理诱导的4个DREB1/CBF基因中，A6的dreb1a、DREB1D、dreb1e转录本水平高于WT。冷处理后的游离氨基酸浓度在A6和WT之间也存在差异。结果表明，与WT相比，A6的DREB1/CBF表达、CAT活性和游离氨基酸浓度对冷的响应发生了差异，这与A6的耐寒性增强有关。
Seashore paspalum (Paspalum vaginatumSwartz) is a commonly used warm-season turfgrass with superior salt tolerance. Low temperature is one of the major abiotic stresses limiting its growth and plantation regions. A protocol for ethyl methane sulphonate (EMS) induced mutations from embryogenic callus and selection of seashore paspalum mutant line with enhanced cold tolerance was established in the study. Treatment of embryogenic callus with 5 h of 0.8% EMS resulted in an approximate 50% survival rate of callus, which was used for inducing mutations from embryogenic callus of seashore paspalum. One mutant line (A6) with enhanced cold tolerance was selected and identified from about 10,000 regenerated plantlets. A6 had lower TEL50(the temperature resulted in 50% electrolyte leakage) and higher survival rate than its wild type (WT) plants after 7 days of cold acclimation. Antioxidant defense system was responsive to low temperature in both genotypes, while higher CAT activity was maintained in A6 than in WT after 3 days of cold treatment. Among four DREB1/CBF genes induced by cold treatment, higher levels ofDREB1A,DREB1D,DREB1Etranscripts were observed in A6 than in WT. Free amino acids concentrations in response to cold treatment also showed difference between A6 and WT. The results suggest that the response of DREB1/CBFs expression, CAT activity, and free amino acids concentrations to cold is differentially altered in A6 compared with WT, which is associated with the enhanced cold tolerance in A6.