摘要
通过等渗的NaCl和PEG溶液模拟盐分和水分胁迫,设置渗透梯度,在控制条件下对杠柳种子的萌发过程中总萌发率、幼苗鲜重、胚根生长、种子活力、发芽值等指标系统研究,对种子萌发率与渗透势之间关系进行回归分析,主要结果包括:(1)杠柳种子萌发过程中总萌发率、幼苗鲜重、活力指数和发芽值四项指标均随NaCl和PEG溶液的渗透势降低逐渐下降,综合研究活力指数和发芽值表明渗透势≥-0.5 MPa和≤-1.4 MPa时,PEG对种子萌发抑制作用大于NaCl,其他情况相反;(2)杠柳种子逐日萌发率和胚根日变化研究表明,与NaCl相比,PEG推迟杠柳种子萌发,并且对胚根增长抑制作用较大;(3)建立盐分和水分胁迫条件下种子萌发率与渗透势回归方程,发现杠柳种子在PEG胁迫下的萌发临界值和极限值为-1.0和-1.4 MPa,在NaCl胁迫下是-0.9和-1.3 MPa,解除胁迫条件,不同处理的杠柳种子复水萌发率均达到100%。说明杠柳具有良好的耐盐抗旱的特性。
The seed germination rates, seeding fresh weights, daily taproot lengths, seed vigor indexes and germination value of Periploca sepium Bge. was investigated under iso-osmotic potential NaCl and PEG with different osmotic potential. The regression analyses were done between the seed germination and different osmotic potential. It was shown that （ 1 ） the total germination rates, seeding fresh weights, seed vigor indexes and seed germination value of P. sepium Bge. tended to decrease as the osmotic potential of NaCl and PEG become intensified; the seed germination was restrained more seriously by PEG than by NaCl under the high osmotic potential （ ≥ -0.5 MPa） ,and low osmotic potential （ ≤ - 1.4 MPa） through meta-analysing seed vigor indexes and germination value, but it reversed under other ranges; （2）the daily germination rates and taproot lengths of P. sepium Bge. indicated that compared with NaCl , PEG delayed the seed germination and inhibited taproot lengths growth more seriously; （3）the regression equation between the seed germination and different osmotic potential under salt and water stress showed that the critical value of the seed of P. sepium Bge. was - 0.9 MPa and the maximum value was - 1.3 MPa under NaCl, while they were - 1.0 MPa and - 1.4 MPa under the PEG. When the osmotic stress was released, the germination recovery rates of the different osmotic potential has achieved 100%. It was resulted that P. sepium Bge. owns the characteristics of salinity tolerance and drought resistance.
出处
《植物研究》
CAS
CSCD
北大核心
2008年第4期465-470,共6页
Bulletin of Botanical Research
基金
天津市科技发展项目(05YFGZNC01200)
天津师范大学服务天津市和滨海新区专项研究计划项目(52L120)
关键词
等渗溶液
种子萌发
活力指数
发芽值
iso-osmotic
seed germination
seed vigor indexes
germination value of seed
