水分胁迫对3个不同种源柔枝松种子萌发的影响

Effects of water stress on the seed germination periods of three Pinus flexilis James populations

用不同浓度PEG-6000的Hoagland溶液模拟水分胁迫条件,通过萌发率、幼苗鲜重、活力指数、抗旱指数4个指标对来自美国的3个柔枝松种源种子的发芽特性进行研究,并运用隶属函数法对其进行综合评价。研究结果表明:(1)随着干旱胁迫程度的加剧,3个柔枝松种源的萌发率、幼苗鲜重、活力指数、抗旱指数都出现了不同程度的下降。且亚利桑那州种源下降的幅度最大。(2)亚利桑那州种源在发芽期的抗旱性好于另外两个种源。3个种源的综合评价值从大到小依次分别为:亚利桑那州0.561;犹他州0.380;内华达州0.132。(3)低浓度的PEG-6000的Hoagland溶液对亚利桑那州和犹他州种源的柔枝松发芽生长具有一定的促进作用。

Taking the Hoagland solution gith different consistence of PEG- 6000 as water stress, the germination characteristic of three Pinus flexilis James populations was studied by seed germination rates, vigor index, seedling fresh weights,and drought resistance index. The result indicated： （ 1 ） As the drought became intensified the total seed germination rates, seedling fresh weights, vigor indexes and fresh weights of three Pinus flexilis James populations tended to decline and Arizona population presented the largest decrement. （2） In the period of germination, the population of Arizona exceeded the other populations in drought resistance. The numerical value of compositive evaluation in turns was：Arizona 0.561 ; Utah：0.380; Nvada：0.132. （3）The low consistence Hoagland solution with PEG- 6000 had the effect on improving Pinus flexilis James seed germination.