Recognising which life-history factors can potentially explain the success of biological invasions is essential to understand why certain exotic species are more successful to invade a given system than others, and also to better predict invasion outcomes. We focused on the three most planted pine tree species in Southern Brazil – Pinus elliottii, P. caribaea and P. oocarpa – as a natural system to test the hypothesis that some key vital attributes – fecundity (number of seeds produced), seed viability, germinability, seedling growth vigour (biomass and stem length) – could be driving the greater invasion of P. elliottii in the region. We collected seeds of P. elliottii var. elliottii, P. caribaea subsp. hondurensis and P. oocarpa in two sites of similar climate and soil in the Cerrado biodiversity hotspot. Seeds were tested for viability and germinability, and seed production was estimated. Under laboratory conditions, we evaluated seedling survival, stem and root development, biomass production and mortality for each species. Although P. elliottii is regarded as the most successful invasive pine species in the Cerrado, it did not outperform the other pines in terms of seed viability, germinability and seedling survival, and it had the slowest growth. P. elliottii did produce, however, at least twice as many seeds as the other species. P. caribaea revealed high seed viability and seedling survival, the fastest seedling development, but low seed production. P. oocarpa showed the lowest seed viability, but fast root growth and very low seedling mortality. Our results suggest seed production is a key factor for P. elliottii invasion success. However, given the strong performance of P. caribaea and P. oocarpa for germinability and growth, we emphasise the risk of both species also becoming successful invaders in the Cerrado. We highlight the need for constant monitoring of emerging pine individuals in native ecosystems to avoid future invasions.

中文翻译：

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早期发展阶段的人口统计率能否证明塞拉多生物多样性热点中三种松树物种的入侵成功？

认识到哪些生活史因素可以潜在地解释生物入侵的成功对于理解为什么某些外来物种比其他物种更成功地入侵给定系统以及更好地预测入侵结果至关重要。我们专注于巴西南部种植最多的三种松树树种——Pinus elliottii、P. caribaea和P. oocarpa——作为一个自然系统来测试一些关键的重要属性——繁殖力（产生的种子数量）、种子活力、发芽性、幼苗生长活力（生物量和茎长）——可能推动P. elliottii在该地区的更大入侵。我们收集了P. elliottii var 的种子。艾略蒂, P. caribaea subsp. hondurensis和P. oocarpa在塞拉多生物多样性热点的两个气候和土壤相似的地点。测试种子的活力和发芽能力，并估计种子产量。在实验室条件下，我们评估了每个物种的幼苗存活、茎和根发育、生物量产生和死亡率。虽然P. elliottii被认为是塞拉多最成功的入侵松树物种，但它在种子活力、发芽率和幼苗成活率方面并没有优于其他松树，而且它的生长速度最慢。然而，P. elliottii产生的种子数量至少是其他物种的两倍。加勒比松表明种子活力和幼苗成活率高，幼苗发育最快，但种子产量低。P. oocarpa表现出最低的种子活力，但根系生长速度快，幼苗死亡率非常低。我们的结果表明种子生产是P. elliottii入侵成功的关键因素。然而，鉴于P. caribaea和P. oocarpa在发芽性和生长方面的强劲表现，我们强调这两种物种也有成为塞拉多成功入侵者的风险。我们强调需要不断监测本地生态系统中新出现的松树个体，以避免未来的入侵。