Data from: Genetic evidence for a Janzen-Connell recruitment pattern in reproductive offspring of Pinus halepensis trees.

Effective seed dispersal, combining both dispersal and post-dispersal (establishment) processes, determines population dynamics and colonization ability in plants. According to the Janzen-Connell (JC) model, high mortality near the mother plant shifts the offspring establishment distribution farther away from the mother plant relative to the seed dispersal distribution. Yet, extending this prediction to the distribution of mature (reproductive) offspring remains a challenge for long-living plants. To address this challenge we selected an isolated natural Aleppo pine (Pinus halepensis) population in Mt. Pithulim (Israel), expanded from five ancestor trees in the beginning of the 20th century into ~2000 trees today. Using nine microsatellite markers, we assigned parents to trees established during the early stages of population expansion. To elucidate the effect of the distance from mother plant on post-dispersal survival, we compared the effective seed dispersal kernel, constructed based on the distribution of mother-offspring distances, to the seed dispersal kernel, computed based on simulations of a mechanistic wind dispersal model. We found that the mode of the effective dispersal kernel is shifted farther away than the mode of the seed dispersal kernel, reflecting increased survival with increasing distance from the mother plant. The parentage analysis demonstrated a highly skewed reproductive success and a strong directionality in effective dispersal corresponding to the wind regime. We thus provide the first evidence that JC effects act also on offspring that become reproductive and persisted as adults for many decades, a key requirement in assessing the role of post-dispersal processes in shaping population and community dynamics.有效种子扩散结合扩散过程与扩散后（建植）过程，决定了植物的种群动态与定殖能力。根据扬岑-康奈尔（Janzen-Connell, JC）模型，母株附近较高的死亡率会使得子代建植分布相较于种子扩散分布，向远离母株的方向偏移。然而，将这一预测推广至成熟（可繁殖）子代的分布，对于长寿植物而言仍是一项挑战。为解决这一挑战，我们选取了以色列皮图勒姆山一处孤立的天然阿勒颇松（Pinus halepensis）种群，该种群于20世纪初由5株祖先树木发展而来，如今种群规模已达约2000株。我们利用9个微卫星标记（microsatellite markers），对种群扩张早期阶段建植的植株进行了亲权归属分析。为阐明母株距离对扩散后存活的影响，我们将基于母子距离分布构建的有效种子扩散核，与基于机械性风力扩散模型模拟得到的种子扩散核进行了对比。我们发现，有效扩散核的众数相较于种子扩散核的众数向更远位置偏移，这反映出随着与母株距离增加，植株存活概率升高。亲权分析（parentage analysis）结果显示，繁殖成功率存在高度偏态分布，且有效扩散存在与区域风向对应的强烈方向性。因此，我们首次提供证据表明，扬岑-康奈尔效应同样作用于那些达到繁殖年龄并存活数十年的子代，这是评估扩散后过程在塑造种群与群落动态中作用的关键前提。