The objectives of this study were to investigate genetic variation and association of the traits of the laticiferous system with rubber yield in young and adult rubber tree progenies Hevea brasiliensis, and compare the traits of the laticiferous system at different heights of the adult trees. The genetic material is composed of progenies from open pollination from the rubber tree breeding program of IAC, evaluated in the experimental field of UNESP in Ilha Solteira, SP, Brazil, in the young and adult phases, and in the Polo Regional Alta Mogiana of the Agência Paulista de Tecnologia do Agronegócio in Colina, SP, Brazil in the young phase. A randomized block experimental design was used with 30 treatments (progenies), three replications, and 10 plants per plot. The following traits were evaluated: rubber yield (RY), virgin bark thickness (BT), number of rings of laticiferous vessels (NR), and mean distance between consecutive rings of the laticiferous vessels (MD). The individual statistical analyses and repeated measurements were performed through mixed linear models using the REML/BLUP (Restricted Maximum Likelihood/Best Linear Unbiased Prediction) procedure. Genetic and phenotypic correlations were also estimated. The accuracy estimates ($\hat{A}c$) for the traits in the two locations were higher (> 0.7), indicating good perspectives in a breeding program. The coefficient of genetic variation (CVg %) showed low variation between the sites: BT (4.5–7 %), NR (14.1–18.3 %), and MD (15–18.2 %). The NR expressed higher heritabilities and was therefore the best trait of the laticiferous system for predicting genetic values; it showed expressive genetic correlations with RY, and may be used in indirect selection. BT did not show progeny × height interaction, indicating that the classification of the progenies was the same, regardless of the tree height at collection. To select progenies in common in the young and adult ages, using analysis of measurements repeated in time, the most suitable height for collection of samples in the adult progenies for the traits of the laticiferous system was up to 80 cm. The traits of the laticiferous system collected at 30 cm in young progenies are associated with RY, both in the youth phase and in the adult phase. They can be used to assist in early or indirect selection of rubber tree progenies.

本研究的目的是研究巴西橡胶树幼苗和成年橡胶树后代的乳管系统性状的遗传变异及其与橡胶产量的关联，并比较成树不同高度的乳管系统性状。遗传物质由开放授粉的后代组成来自 IAC 的橡胶树育种计划，在巴西伊利亚索尔泰拉的 UNESP 实验田的年轻和成年阶段以及在科利纳的 Agência Paulista de Tecnologia do Agronegócio 的 Polo 地区 Alta Mogiana 进行了评估，巴西处于年轻阶段。随机区组实验设计用于 30 个处理（子代）、3 个重复和每个小区 10 个植物。评估了以下性状：橡胶产量（RY）、原始树皮厚度（BT）、乳管环数（NR）和乳管连续环之间的平均距离（MD）。使用 REML/BLUP（受限最大似然/最佳线性无偏预测）程序通过混合线性模型进行单独的统计分析和重复测量。还估计了遗传和表型相关性。准确度估计（$\widehat{\mathrm{一个}}C$)，因为这两个位置的性状较高（> 0.7），表明育种计划的前景良好。遗传变异系数 (CVg %) 显示位点之间的低变异：BT (4.5–7 %)、NR (14.1–18.3 %) 和 MD (15–18.2 %)。NR 表现出更高的遗传力，因此是预测遗传值的乳管系统的最佳性状；它显示出与 RY 的表达遗传相关性，可用于间接选择。BT没有显示后代×高度相互作用，表明后代的分类是相同的，无论收集时的树高如何。为了选择年轻和成年时期的共同后代，使用及时重复的测量分析，乳管系统性状的成年后代最适合采集样品的高度为80 cm。在年轻后代中收集的 30 厘米处的乳管系统的特征与 RY 相关，无论是在青年阶段还是在成年阶段。它们可用于协助早期或间接选择橡胶树后代。