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作 者 ：王宏飞, 魏岩, 黄振英

期 刊 ：植物生态学报 2007年 31卷 6期 页码：1046-1053

关键词：散枝猪毛菜；种子多型性；种子萌发；生理休眠；划伤；

Keywords:Salsola bracchita, seed polymorphism, seed germination, physiological dormancy, scarification,

摘 要 ：散枝猪毛菜（Salsola bracchita）主要分布于新疆准噶尔荒漠，具有很强的抗干旱和抗盐碱能力。该文对散枝猪毛菜的果实进行了观察，表明
散枝猪毛菜具有4种类型的散布单位和果实，这4种果实在形状、大小、颜色和着生方式上均有显著差异。A型果实绿色、球形、大，着生方式为
横生，宿存花被革质，背部有紫红色翅状附属物，直径为(2.161±0.138) mm，单粒重为(3.810±0.113)mg；B型果实绿色、大、扁平、长圆形
，着生方式为直立，宿存花被革质，背部有翅状附属物，长为(2.062±0.188) mm，宽为(1.720±0.14 8) mm，单粒重为(2.665±0.113) mg；C
型果实绿色、大、扁平、长圆形，着生方式为直立，宿存花被膜质，背部无翅状附属物，长为(2.239±0.277) mm，宽为(1.844±0.150) mm，
单粒重为(2.723±0.559) mg；D型果实黄色、小、扁平、长卵形，着生方式为直立，宿存花被膜质，背部无翅状附属物，长为(1.678±0.163)
mm，宽为(1.390±0.110) mm，单粒重为 (0.928±0.025) mg。A型、B型和C型种子（果实）在5 ℃/15℃、5 ℃/25 ℃、15 ℃/25 ℃（暗12 h/
光12 h）变温条件下萌发率＞68%，且B型和C型种子比A型种子有较高的萌发率和萌发速率。D型种子在3种变温条件下萌发缓慢，最终萌发率始
终维持在较低水平（＜20%），划破果皮和种皮能够显著提高D型种子的萌发率和萌发指数，表明D型种子处于生理休眠状态。散枝猪毛菜的种子
多型性是对荒漠异质环境的一种适应。

Abstract:Aims Salsola bracchita has four types of perianth-enclosed utricles, utricles and seeds. We investigated the role of utricle
polymorphism in seed dispersal and germination to better understand how S. bracchita is adapted to its desert habitat.
Methods Twenty plants of S. bracchita were selected randomly to observe the morphology of perianth-enclosed utricles,
including persistence of perianth and wings, utricle shape and color and location of fruit on mother plant. Seeds of the
four types were germinated in incubators with 12 h photoperiod and 12 h thermo periods (dark/light) of 5 ℃/15 ℃, 5 ℃/25 ℃
, and 15 ℃/25 ℃ for 20 d. Type D seed was scarified and then germinated for 20 d at the three different thermo periods to
determine its dormancy characteristics. 
Important findings Salsola bracchita produces four types of fruits (utricles) that differ in shape, size, seed color and
external structure. Type A and B fruits can be dispersed by wind far from mother plants. Germination percentages of type A
seeds at all three thermo periods were >70%, and there were no significant differences (p>0.05). Germination percentages of
type B seeds were all >68%, and there were significant differences (p<0.05), with highest germination percentage and
germination index at 5 ℃/25 ℃ (dark/light) (>80%). Type C fruits have tepals without wings and are dispersed near mother
plants. Germination percentages of type C seeds were all >80%, and there were no significant differences (p>0.0 5). Rate and
final percentages of germination of type B and type C seeds were higher than that of type A seeds. Type D fruits also are
mainly dispersed near mother plants. Freshly matured type D seeds are in physiological dormancy because its germination is
slow and low (<20%). Seed coat scarification of type D seeds can hasten and increase the seed germination percentage (p<0.01)
and germination index (p<0.01) in each of the thermo periods.

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