关键词: 无性系生长, 构件, 实验同生群, 异速生长, 休眠芽库, 活动芽库, 繁殖策略, 植物生态学

Abstract: To evaluate the impact of actual vegetative propagation ability (AVPA) of clones on population growth,an experimental cohort of Leymus secalinus was established under common-garden conditions. AVPA was estimated by using the vegetative reproductive indexes of a single clone. This phased and continuous growth patterns of module production and growth based on two-year experimental observations of the cohort of L. secalinus were analyzed. A bud flow model was also constructed based on the findings of the experiment. The vegetative reproductive indexes such as total length of rhizomes,number of rhizomes,and number of buds in the experimental cohort clone of L. secalinus in the same year and the following year all had significant plasticity,with coefficients of variation greater than 74%. The increase in AVPA between years was greater than that of vegetative propagation ability in the experimental cohort clones of L. secalinus. In the rhizome growth sequence,the total length of rhizomes,number of rhizomes,number of ramets,total number of active buds,and total number of live modules all follow a classic exponential growth pattern during the phased and continuous growth processes. In the bud flow,the failure rate of vegetative propagation of the experimental cohort in the two years was less than 1%. The success probability of vegetative reproductive was relatively high,with 40.6% in the first year of transplantation and 58.1% in the second year. Among them,the output rates of ramets were 4.3 times and 5.5 times that of the rhizome,respectively. The actual vegetative fecundity plasticity variations of AVPA within the experimental cohort clones of L. secalinus reflects survival strategies of population,while small clones prioritize occupying more above ground space.

Key words: Clone growth, Module, Experimental cohort, Allometric growth, Dormant bud bank, Active bud bank, Reproductive strategy, Plant ecology