沙埋和种子大小对柠条锦鸡儿种子萌发、出苗和幼苗生长的影响  

Effects of sand burial and seed size on seed germination,seedling emergence and growth of Caragana korshinskii Kom.(Fabaceae)

作　　者：杨慧玲[1,2] 梁振雷[1] 朱选伟[2] 梅世秀[1] 王会勤[1] 申艳[1] 黄振英[2] 

机构地区：[1]河南农业大学生命科学学院,郑州450002 [2]中国科学院植物研究所植被与环境变化国家重点实验室,北京100093

出　　处：《生态学报》2012年第24期7757-7763,共7页Acta Ecologica Sinica

基　　金：国家自然科学基金面上项目(30900216);中国博士后科学基金(20080430589);河南农业大学博士启动基金(30200224)

摘　　要：研究了沙埋深度和种子大小对内蒙古毛乌素沙地植被群落中占优势的柠条锦鸡儿(Caragana korshinskii Kom.)种子萌发、出苗、幼苗存活和生长的影响。结果表明,沙埋深度显著影响柠条锦鸡儿的种子萌发率、休眠率、出苗率、幼苗存活率及生物量。在0.5—2 cm的浅层沙埋下,种子萌发率、出苗率、幼苗存活率及生物量最高,休眠率最低;沙埋深度≥4 cm时,柠条锦鸡儿的种子萌发率、出苗率、幼苗存活率及生物量随着沙埋深度增加显著降低,而休眠率却显著升高;沙埋深度≥12 cm时,柠条锦鸡儿种子不能够出苗,幼苗也不能够存活。种子大小对柠条锦鸡儿种子萌发率没有显著影响,但对出苗率、幼苗存活率及生物量影响显著。在各个沙埋深度下,不同大小的柠条锦鸡儿种子间的萌发率没有显著差异。当沙埋深度≤6 cm时,不同大小的柠条锦鸡儿种子在同一沙埋深度下的出苗率间没有显著差异;但当沙埋深度≥8 cm时,在同一沙埋深度下,大种子的出苗率显著高于中种子和小种子的出苗率,而中种子和小种子出苗率间没有显著差异。0.5—10 cm的沙埋深度中,除6 cm和8 cm深度下中种子和小种子萌发幼苗的生物量间没有显著差异外,其余深度下,大种子萌发的幼苗的存活率及生物量显著高于同一沙埋深度下中种子萌发的幼苗的存活率及生物量,后者又显著高于小种子萌发的幼苗的存活率及生物量。可能正是种子萌发对沙埋环境的忍耐或响应能力以及种子的多态性提高了柠条锦鸡儿在毛乌素沙地的适合度,为其在流动或半流动沙丘环境中成功定居并形成优势群落奠定了基础。Two pots experiments were conducted in a greenhouse to test the effects of sand burial and seed size on seed germination and seedling emergence, survival and growth of Caragana korshinskii Kom. , a dominant perennial sand-fixating legume shrub in Mu Us Sandland. Sand burial significantly affected seed germination, seed dormancy, and seedling emergence, survival and biomass of C. korshinskii. Percentages of seed germination and seedling emergence, survival and biomass were highest at burial depths of 0.5 to 2 cm, and they decreased with the increase in depth of sand burial to≥4 cm. In contrast, the percentage of seed dormancy was lowest at depths of 0.5 to 2 cm, and it increased with an increase in depth from 4 to 12 cm. No seedlings emerged or survived at depths ≥ 12 cm. Seed size noticeably affected emergence, survival and biomass of C. korshinskii seedlings, but it did not affect seed germination. At all burial depths, germination percentages did not differed markedly among different size seeds. At depths ≤6 cm, percentages of seedlings that emerged from seeds of different sizes were not significantly different, but seedling emergence was higher from large seeds than from medium or small seeds at depths ≥ 8 cm. Moreover, survival and biomass of seedlings that originated from large seeds were higher than those of seedlings from medium seeds, which, in turn, were higher than those of seedlings from small seeds at each depth from 0.5 to 10 cm except at 6 or 8 cm. We speculate that tolerance to sand burial and diversity of seed size increase the fitness of C. korshinskii, which contributes to its dominance in mobile and semi-mobile sand dunes of Mu Us Sandland.

关 键 词：柠条锦鸡儿 沙埋深度 种子大小 种子萌发 幼苗出土 幼苗生物量 

分 类 号：S793.3[农业科学—林木遗传育种]