Data from: Leafing intensity and the fruit size/number trade-off in woody angiosperms

1. A sample of woody angiosperm species was used to test a central prediction of the ‘leafing intensity premium’ hypothesis: higher leafing intensity (number of leaves produced per unit dry mass of shoot vegetative tissue produced in the same growing season) confers a larger bud bank (i.e. number of axillary meristems per unit shoot tissue) that can be deployed for reproduction, and thus confers generally greater fruit numbers, and hence higher potential fecundity allocation (i.e. fecundity per unit size of the supporting shoot tissue that is produced in the same growing season. 2. Current-year shoots (i.e. bearing leaves) were collected to record: shoot dry mass, total number of leaves, total number of fruits or fruit clusters (if derived from inflorescences), mean individual leaf dry mass, and mean individual fruit dry mass. Sampled individuals (shrubs and trees) were also measured for body size (main stem height and circumference). 3. Species with larger individual fruit (or fruit cluster) mass have generally larger leaves but they also have a negative trade-off relationship with ‘fruiting intensity’ — i.e. the total number of reproductive meristems producing fruits (or fruit clusters) per unit dry mass of shoot vegetative tissue produced in the same growing season. Variation in fruiting intensity, however, is better predicted by a positive relationship with variation in bud bank size. 4. Species with smaller leaf size (dry mass) have generally higher leafing intensity; species with higher leafing intensity in turn have generally higher fruiting intensity; and species with higher fruiting intensity in turn have generally higher potential fecundity allocation (based on the typical species maximum number of seeds per fruit, obtained from published floras). Species with smaller body size have generally higher potential fecundity allocation, but body size had no significant relationships with other measured traits when controlling for phylogeny (using phylogenetically independent contrasts). 5. Synthesis. Our results indicate that bud bank size is an important functional trait for defining adaptive strategy in woody angiosperms. A larger bud bank is generated by higher leafing intensity, which in turn generates higher fruiting intensity, thus generating greater potential fecundity allocation. These traits will be important for maximizing reproductive economy — i.e. capacity to produce offspring despite growth or body size limitation (e.g. due to crowding/competition, or because of limited time available for growth, flowering, pollination, or fruit/seed maturation).

1. 本研究选取木质被子植物（woody angiosperm）物种样本，用以检验“叶生强度溢价假说（leafing intensity premium hypothesis）”的核心预测：更高的叶生强度（即同一生长季内，单位营养枝条组织干重所产生的叶片数量）可形成更大的芽库（bud bank，即单位枝条组织的腋生分生组织（axillary meristems）数量），该芽库可投入生殖生长，因此通常能产生更多果实，进而实现更高的潜在繁殖分配（即同一生长季内，单位支撑枝条组织干重对应的繁殖产出）。
2. 采集当年生带叶枝条，记录以下指标：枝条干重、总叶片数、果实或果簇总数（若由花序发育而来）、单叶平均干重以及单果平均干重。同时对作为采样对象的灌木与乔木个体，测定其个体大小指标，包括主茎高度与茎干周长。
3. 单果（或果簇）干重更大的物种，通常叶片也更大，但二者与“结实强度（fruiting intensity）”呈负相关权衡关系——结实强度指同一生长季内，单位营养枝条组织干重对应的产生果实（或果簇）的生殖分生组织总数量。不过，结实强度的变异更可通过其与芽库大小变异的正相关关系进行预测。
4. 叶片干重更小的物种，通常叶生强度更高；叶生强度更高的物种，其结实强度通常也更高；而结实强度更高的物种，其潜在繁殖分配通常也更高（潜在繁殖分配基于已发表植物志中记载的物种单果典型种子数计算）。个体体型更小的物种，通常潜在繁殖分配更高，但在控制系统发育影响（采用系统发育独立对比（phylogenetically independent contrasts）方法）后，体型与其他测定性状无显著相关关系。
5. 综合分析结果表明，芽库大小是界定木质被子植物适应性策略的关键功能性状。更高的叶生强度可形成更大的芽库，进而提升结实强度，最终实现更高的潜在繁殖分配。上述性状对于最大化繁殖经济性至关重要——即即便在生长或体型受限（例如由于种群拥挤/种间竞争，或用于生长、开花、传粉以及果实/种子成熟的时间有限）的情况下，仍具备产生后代的能力。