关键词: 繁殖能力, 繁殖性状, 入侵植物, 本地植物, 土壤养分

Abstract: Understanding the reproductive strategy and soil nutrient efficiency of plants is fundamental to identify the mechanisms of plant invasion and success. In order to understand how soil nutrient conditions influence reproductive capacity in native and invasive plants, and specifically whether nutrient addition increases the reproductive capacity more for the invasive plants, we conducted a common garden experiment. In low and high soil nutrient conditions we measured and compared the reproductive traits of annual Asteraceae plants including the invasive species (Praxelis clematidea, Ageratum conyzoides, Bidens pilosa) and native species (Vernonia cinerea, Emilia sonchifolia, Eclipta prostrata). We found that nutrient addition increased the height at flowering, plant height, aboveground biomass, single seed weight, total inflorescence number, seed number per inflorescence, total seed number and total seed weight of all Asteraceae plants, and also advanced the flowering time and extended the flowering period length. However, nutrient addition increased the flowering height and single seed weight of invasive species more than those of native species, and in some invasive plants (P. clematidea and A. conyzoides) it increased the reproductive capacity compared to some native plants (V. cinerea and E. prostrata). The total seed number and total seed weight of B. pilosa and E. sonchifolia were small under both low and high soil nutrient conditions. The total seed number of the native E. prostrata was higher than that of the three invasive plants under low soil nutrient conditions, and its total seed weight was higher than that of the three invasive plants. These results indicate that high soil nutrients promote the reproductive capacity of some but not all invasive plants compared with native plants.

Key words: reproductive capacity, reproductive traits, invasive plant, native plant, soil nutrient