Purpose of Review

In this review, we synthesise current knowledge on trade-offs among traits in key fitness dimensions and identify major research gaps with the intention of laying the groundwork for a rapid advance in tree breeding for multiple objectives as a key contribution to the sustainability of planted forests in the future.

Recent Findings

Trade-offs among growth, reproduction, defence, stress tolerance and product quality predicted theoretically have been reported experimentally in many breeding programmes. Among these trade-offs, the genetic linkage between resistance against biotic threats and growth (or other relevant traits) is particularly critical for the current and future management of forest genetic resources. Maintaining tree growth and wood quality in the novel environments of the future requires the assessment of genetic correlations of target traits with phenology, closely linked to survival to temperature extremes. Improving our current knowledge on the genetic trade-offs of drought tolerance as a breeding objective in forest trees obligates a more precise definition of both the specific traits and the experimental conditions. Published evidence suggests that common target traits in breeding programmes may trade-off with reproductive success and fire-adaptation, and the simultaneous improvement of growth and wood quality traits still remains as a constraint in traditional tree breeding.

Summary

Changing environments combined with pests and diseases are challenging plantation forestry worldwide, which implies an urgent need to develop new improvement strategies to build the resilience of forestry for our future environments. It is essential to have a better understanding of how traits interact, especially those important for production, climate and biotic threat resilience, but much of the information is still missing. Since many key trade-offs are affected by the environment, we need new studies under novel environments to forecast levels of multi-trait integration in breeding populations.

中文翻译：

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树木表型的权衡和性状整合：遗传资源可持续利用的后果

审查目的

在这篇综述中，我们综合了当前关于关键适应性维度性状权衡的知识，并确定了主要研究差距，旨在为实现多个目标的树木育种的快速进展奠定基础，作为对人工林可持续性的关键贡献将来。

最近的发现

理论上预测的生长、繁殖、防御、抗逆性和产品质量之间的权衡已在许多育种计划中通过实验报告。在这些权衡中，生物威胁抵抗力与生长（或其他相关性状）之间的遗传联系对于当前和未来的森林遗传资源管理尤为重要。在未来的新环境中保持树木生长和木材质量需要评估目标性状与物候的遗传相关性，这与极端温度下的生存密切相关。提高我们目前对作为林木育种目标的耐旱性遗传权衡的认识，需要对具体性状和实验条件进行更精确的定义。已发表的证据表明，育种计划中的共同目标性状可能会与繁殖成功和火适应进行权衡，并且生长和木材质量性状的同时改善仍然是传统树木育种的限制。

概括

不断变化的环境加上病虫害正在给全世界的人工林业带来挑战，这意味着迫切需要制定新的改进战略，以增强林业对未来环境的适应能力。必须更好地了解性状如何相互作用，特别是那些对生产、气候和生物威胁抵御能力很重要的性状，但仍有许多信息缺失。由于许多关键的权衡都受到环境的影响，我们需要在新环境下进行新的研究来预测育种种群中多性状整合的水平。