高寒草甸小嵩草种群繁殖生态学研究  

Study on reproductive ecology of Kobresia pygmaea population in alpine meadow

作　　者：邓自发[1] 谢晓玲[1] 周兴民[2] 王启基[2] 

机构地区：[1]南通师范学院生命科学与技术系,江苏南通226007 [2]中国科学院西北高原生物研究所,西宁810001

出　　处：《西北植物学报》2002年第2期344-349,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：中国科学院"九五"重大项目 ( KE95 T-0 4 )项目;南通师范学院课题资助

摘　　要：研究从繁殖生态学的角度对高寒草甸小嵩草 (Kobresia pygmaea)种群进行了初步研究。结果表明 :小嵩草属寒冷中生密丛短根茎地下芽植物 ,在高寒生境中采用以营养繁殖为主、有性繁殖为辅的繁殖策略 ,具体体现在以下几个方面 :虽然小嵩草种子产量达45 5 3 .8粒 /m2 ,但种子萌发率较低 ,室内和野外萌发率分别仅有 4%和 1 % ,经氢氧化钠溶液和赤霉素溶液处理后的种子萌发率分别为 1 %和 2 % ,而剥去种皮后种子萌发率达 5 2 .6 % ,种皮坚硬是造成种子萌发率低的主要原因 ;进入种子库、保留至返青期且具有活性的种子仅占种子总数的 2 4 .3 5 % ,其室内萌发率仅有 3 % ,而在野外理论实生苗仅为 1 1 .0 9个 /m2 ,与此相反小嵩草营养繁殖所形成的新个体数为 6 2 5 6 .2 5个 /m2 ,远远多于种子萌发所形成的实生苗数。此外 ,小嵩草营养繁殖效力也远高于有性繁殖效力 ,营养繁殖效力占总繁殖效力的 90 .92 %。This paper studied on reproductive strategies of Kobresia pygmaea in alpine meadow from sexual reproduction,vegetative reproduction and reproductive efforts respectively.The results show that the seed output of Kobresia pygmaea is 4 553.8 per \{unit\}(m 2),and in field is only 4% and 1% respectively,and there is only 1% and 2% seed germinate after treated by pH8.0~8.5 NaOH and 1‰ GA 3 (24 h)separately, but the germination is 52.6% when seed vessel is removed,so the main reason which lead to low germination is hard seed vessel;there is only 24.35% seed which get into seed bank and retain to grass greening,and keep vitality,and the germination in fit condition is only 3%.So the seedling is only 11.09 per unit(m 2) in field,but the new ramets are 6 256.25 unit(m 2) of Kobresia pygmaea by vegetative reproduction.In addition,vegetative reproductive effort is more than sexual reproductive effort,and it is 90.92% in all of reproductive effort.In a word,the reproductive strategy of Kobresia pygmaea is vegetative reproduction as main,sexual reproduction as secondary in alpine condition.

关 键 词：高寒草甸 小嵩草 无性系小株 繁殖效力 繁殖策略 种群繁殖生态 

分 类 号：S812[农业科学—草业科学] Q948.112.4[农业科学—畜牧学]