PREMISE Distylous species possess two floral morphs with reciprocal positioning of stigmas and anthers that is hypothesized to promote disassortative pollination. Theoretical models predict equal morph frequencies, but many populations depart from the expected 1:1 ratio, a pattern that often correlates with asymmetric mating between morphs and/or presence of a weak incompatibility system. Variation in reciprocity can also affect the likelihood of disassortative pollination and, hence, reproductive fitness. METHODS We described variation in incompatibility systems and morph ratio in four Erythroxylum species to test if greater deviations from 1:1 ratios occur in populations of self-compatible species. Using adaptive inaccuracy, we described upper and lower organ reciprocity in species and populations and assessed the relationship of reciprocity to population means and coefficients of variation for fruit set to test if reciprocity could predict female reproductive success. RESULTS Morphs occurred in 1:1 ratios in most populations of three Erythroxylum species with distylous self-incompatibility. In self-compatible E. campestre populations showed an excess of the long-styled morph, the short-styled morph, or were monomorphic for the short-styled morph. We detected deviations from reciprocity, with total inaccuracy ranging between 9.39% and 42.94%, and inaccuracy values were lowest in low organs. Across populations, we found a positive relationship between inaccuracy and the coefficient of variation of fruit set. CONCLUSIONS Erythroxylum species showed variation in the distylous syndrome, with changes in the incompatibility system that corresponded with deviations from 1:1 morph ratio, and variation in reciprocity that correlated with variation in female reproductive fitness.

中文翻译：

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Erythroxylum物种和种群的distylous性状和生殖后果的变异模式

前提 Distylous 物种具有两种花的形态，柱头和花药相互定位，被假设为促进异类授粉。理论模型预测相同的变形频率，但许多种群偏离预期的 1:1 比例，这种模式通常与变形之间的不对称交配和/或弱不相容性系统的存在相关。互惠的变化也会影响异种授粉的可能性，从而影响生殖健康。方法 我们描述了四种 Erythroxylum 物种的不相容性系统和变形比的变化，以测试自交物种种群中是否发生了与 1:1 比率的更大偏差。使用自适应误差，我们描述了物种和种群的上下器官互惠，并评估了互惠与种群平均值和果实集变异系数的关系，以测试互惠是否可以预测雌性繁殖成功。结果 在具有二尖瓣自交不亲和性的三种 Erythroxylum 物种的大多数种群中，变形以 1:1 的比例发生。在自相兼容的 E. campestre 种群中，长柱变形、短柱变形或短柱变形是单态的。我们检测到与互惠的偏差，总不准确度在 9.39% 到 42.94% 之间，不准确度值在低器官中最低。在整个种群中，我们发现不准确度与坐果变异系数之间存在正相关关系。