Turkish red pine (Pinus brutia Ten.), is the most important tree species for afforestation in the Mediterranean basin due to its drought tolerance and fast growth rate. Cold damage to trees caused by harsh winter conditions is common on many sites in Turkey. Adaptation to climate change has been investigated primarily through the movement of species from warmer and drier climates, such as the Mediterranean P. brutia, to higher latitudes and cooler sites in central-north Turkey. In order to better guide species and provenances movement to new (and often harsh) environments for afforestation, the limits of tolerance to cold and drought should be better known. Thus, we designed an experiment to quantify the cold hardiness of nine P. brutia provenances originating from two different provenance trials in Turkey (Ankara, cold inner site; Antalya, warm Mediterranean site). Branches sampled at the end of January were exposed to cold temperatures between − 5 and − 40 °C. Visual damage observation, relative electric leakage and chlorophyll fluorometry (CF) screening methods were used to assess variation in cold hardiness among populations. Overall, P. brutia can tolerate winter temperatures up to − 16 °C. Even though there were significant differences on cold hardiness among populations, the operational application is limited due to the reduced magnitude of those differences. Measuring CF was the fastest and most easily replicated method to estimate cold hardiness and was as reliable as REL. We recommend that P. brutia should not be planted in cold areas where minimum annual temperatures are under − 16 °C. We also conclude that even though phenotypic plasticity exists for cold hardiness among the tested populations of P. brutia, the observed differences resulted from acclimation to the conditions of the provenance trial sites rather than from adaptation through natural selection.

土耳其红松（Pinus brutia Ten。）是地中海盆地最重要的造林树木，因为它具有耐旱性和快速的生长速度。严酷的冬季条件对树木造成的冷害在土耳其很多地方都很普遍。主要通过物种的迁移来研究对气候变化的适应性，这些物种从更暖和更干燥的气候（例如地中海假单胞菌）迁移到土耳其中北部的较高纬度和较凉爽的地点。为了更好地指导物种和种源向新的（通常是恶劣的）造林环境迁移，应对寒冷和干旱的容忍度应该更加了解。因此，我们设计了一个实验来量化九种假单胞菌的耐寒性起源于土耳其的两次不同来源试验（安卡拉，内部寒冷地区；安塔利亚，温暖的地中海地区）。一月底采样的分支暴露在− 5至− 40°C的低温下。视觉损伤观察，相对漏电和叶绿素荧光法（CF）筛选方法用于评估人群的抗寒性变化。总体而言，布鲁氏疟原虫可以耐受高达− 16°C的冬季温度。即使人群之间的耐寒性存在显着差异，但由于这些差异的程度有所降低，因此在实际应用中受到了限制。测量CF是评估耐寒性的最快，最容易重复的方法，并且与REL一样可靠。我们建议P. brutia不应将其种植在年最低温度低于− 16°C的寒冷地区。我们还得出结论，尽管在测试的布鲁氏菌种群中存在抗寒性的表型可塑性，但观察到的差异是由于适应种源试验地点的条件而不是由于自然选择的适应性造成的。