Plant reproduction is influenced by abiotic resources and biotic mutualistic and antagonistic interactions, which in turn can be affected by anthropogenic disturbances such as increased fire frequency. Because frequent fires deplete soil fertility and thus decrease resource availability for plants, we hypothesize that increased fire frequency decreases specific leaf area (SLA) and reproductive success. In addition, lower SLA levels in frequently burned sites should decrease herbivore damage because of reduced leaf palatability. Finally, increased fire frequency will have stronger negative effects on specialist insects (seed predators) as compared to generalist feeding insects such as herbivores and pollinators, which can have direct consequences on plant reproduction. Through an integrative path analytical approach, we assess fire frequency effects on the reproductive success of two resprouting legumes from the Chaco Serrano (Desmodium uncinatum and Rhynchosia edulis), estimating the relative importance of SLA along with pollination, insect herbivory and seed predation interactions. Increased fire frequency decreased SLA but it did not affect biotic interactions in both plant species, with the exception of increased leaf herbivory in R. edulis. Sexual reproduction of D. uncinatum was reduced in burned sites but it remained similar across burned and unburned sites in R. edulis. Within burned areas, both species efficiently maximized the allocation to reproduction, showing a conservative strategy in the use of resources when SLA levels are extremely low. Decreased plant fecundity, especially in D. uncinatum, is likely to impact on the density and long-term viability of populations growing in anthropogenic high fire frequency areas.

植物繁殖受到非生物资源以及生物相互和对立相互作用的影响，而反过来又可能受到人为干扰（例如火频率增加）的影响。由于频繁的大火消耗了土壤肥力，从而降低了植物的资源利用率，因此我们假设增加的大火频率会降低比叶面积（SLA）和繁殖成功。此外，由于叶片适口性降低，在经常燃烧的部位降低SLA水平应减少草食动物的损害。最后，与普通食性昆虫（例如草食动物和授粉媒介）相比，增加的火频率对特种昆虫（种子捕食者）具有更大的负面影响，这可能直接影响植物的繁殖。通过综合路径分析方法，乌龙子（Desmodium uncinatum）和可食用的Rhynchosia edulis），估计了SLA以及授粉，昆虫食草和种子捕食相互作用的相对重要性。较高的着火频率降低了SLA，但除了可食红景天中叶片食草性增加外，这两种植物均未影响生物相互作用。在烧伤的部位，D。uncinatum的有性繁殖减少，但在食用的R. edulis中，烧伤部位和未烧伤部位的性繁殖仍然相似。在被烧毁的地区，这两个物种都有效地最大化了繁殖的分配，这在SLA水平极低时显示出资源使用的保守策略。植物繁殖力下降，尤其是在D. uncinatum中可能会影响人为高发火频率区域中增长的人口的密度和长期生存能力。