Department of Botany, Faculty of Science, Kasetsart University, Bangkok, Thailand.
Hevea Research Platform in Partnership, DORAS Center, Kasetsart University, Bangkok, Thailand.
PeerJ. 2024 Aug 8;12:e17877. doi: 10.7717/peerj.17877. eCollection 2024.
Plants allocate resources to growth, defense, and stress resistance, and resource availability can affect the balance between these allocations. Allocation patterns are well-known to differ among species, but what controls possible intra-specific trade-offs and if variation in growth . defense potentially evolves in adaptation to resource availability.
We measured growth and defense in a provenance trial of rubber trees () with clones originating from the Amazon basin. To test hypotheses on the allocation to growth . defense, we relate biomass growth and latex production to wood and leaf traits, to climate and soil variables from the location of origin, and to the genetic relatedness of the clones.
Contrary to expectations, there was no trade-off between growth and defense, but latex yield and biomass growth were positively correlated, and both increased with tree size. The absence of a trade-off may be attributed to the high resource availability in a plantation, allowing trees to allocate resources to both growth and defense. Growth was weakly correlated with leaf traits, such as leaf mass per area, intrinsic water use efficiency, and leaf nitrogen content, but the relative investment in growth . defense was not associated with specific traits or environmental variables. Wood and leaf traits showed clinal correlations to the rainfall and soil variables of the places of origin. These traits exhibited strong phylogenetic signals, highlighting the role of genetic factors in trait variation and adaptation. The study provides insights into the interplay between resource allocation, environmental adaptations, and genetic factors in trees. However, the underlying drivers for the high variation of latex production in one of the commercially most important tree species remains unexplained.
植物将资源分配到生长、防御和应激抗性中，资源的可获得性会影响这些分配之间的平衡。物种间的分配模式众所周知存在差异，但资源可用性如何控制可能的种内权衡，以及生长、防御的变异是否有可能在适应资源可用性的过程中进化。
我们对来自亚马逊盆地的橡胶树（）种源试验中的生长和防御进行了测量。为了检验关于生长、防御分配的假设，我们将生物量生长和乳胶产量与木材和叶片特征、起源地的气候和土壤变量以及克隆的遗传亲缘关系联系起来。
与预期相反，生长和防御之间没有权衡，而是乳胶产量和生物量生长呈正相关，并且都随树体大小增加而增加。这种权衡的缺失可能归因于种植园中高的资源可获得性，允许树木将资源分配到生长和防御上。生长与叶片特征（如叶面积质量、内在水分利用效率和叶片氮含量）呈弱相关，但生长、防御的相对投资与特定特征或环境变量无关。木材和叶片特征与起源地的降雨和土壤变量呈梯度相关。这些特征表现出强烈的系统发育信号，突出了遗传因素在性状变异和适应中的作用。该研究提供了对树木中资源分配、环境适应和遗传因素相互作用的深入了解。然而，对于在商业上最重要的树种之一乳胶产量高变异的潜在驱动因素仍未得到解释。
