Data from: Shade tree traits and microclimate modifications: Implications for pathogen management in biodiverse coffee agroforests

Diversified coffee agroforests modify microclimate conditions in comparison to monocultures, impacting the success of significant plant pathogens, such as Hemileia vastatrix, which causes coffee leaf rust (CLR). However, research is often limited to the dichotomous analysis of shaded agroforestry systems or unshaded monocultures, often overlooking the nuanced effect of shade tree trait diversity. Our study aims to determine the cumulative effects of shade tree canopy architectural characteristics and leaf functional traits in biodiverse agroforests on microclimate modifications and CLR incidence. We measured plot-level microclimate conditions (air temperature, relative humidity, leaf wetness duration, throughfall kinetic energy) in three single-stratum and two double-strata shade tree canopy treatments, including Erythrina poeppigiana, Terminalia amazonia, and Chloroleucon eurycyclum. Commonly reported canopy characteristics and leaf traits were compared to average microclimate conditions and CLR incidence levels. We found that shade tree trait expression significantly explained most microclimate conditions, and that two key shade tree traits (canopy openness, leaf area) significantly explain CLR incidence levels (R2 = 0.211, p = 0.036). Our results highlight the differences in microclimate conditions and CLR incidence among biodiverse agroforests, as well as the important explanatory power of shade tree traits. Specific effects of shade tree traits on pathogen dynamics can cirectly inform agroforestry system design (i.e. shade tree species selection) and sustainable coffee farm management practices (i.e. pruning practices).

相较于单一栽培咖啡种植园，多样化咖啡农林复合系统会对其微气候条件产生调控作用，进而影响重要植物病原菌的侵染成功率，其中以引发咖啡叶锈病（CLR）的咖啡驼孢锈菌（Hemileia vastatrix）为代表。然而，现有相关研究往往仅针对遮阴农林复合系统与无遮阴单一栽培开展二分法分析，常忽略遮阴树木性状多样性所带来的细微调控效应。本研究旨在明确多物种咖啡农林复合系统中，遮阴树木冠层结构特征与叶片功能性状对微气候改变及咖啡叶锈病发病率的累积影响。本研究针对3种单层遮阴冠层处理与2种双层遮阴冠层处理开展样地尺度微气候监测，监测指标涵盖气温、相对湿度、叶片结露时长、穿透降雨动能，供试遮阴树种包括波氏刺桐（Erythrina poeppigiana）、亚马孙诃子（Terminalia amazonia）以及宽环朱缨豆（Chloroleucon eurycyclum）。研究人员将常规观测的冠层特征与叶片性状数据，与样地平均微气候条件及咖啡叶锈病发病率水平进行关联对比。结果显示，遮阴树木的性状表达可显著解释绝大多数微气候变量的变化；而两项关键遮阴树木性状——冠层开度与叶面积——可显著解释咖啡叶锈病的发病率变化（决定系数R²=0.211，p=0.036）。本研究结果揭示了多物种咖啡农林复合系统间微气候条件与咖啡叶锈病发病率的差异，同时凸显了遮阴树木性状所具备的重要解释能力。遮阴树木性状对病原菌动态的具体调控效应，可直接为农林复合系统设计（如遮阴树种筛选）与可持续咖啡种植管理实践（如修剪作业）提供科学依据。