Mitigation of Global Climate Change through Genetic Improvement of Resin Production from Resinous Pines: The Case of IPinus halepensis/I in Greece

Carbon sequestration by forests and storage in biomass has gained great interest globally in climate change mitigation. Resinous pine forests act as ideal carbon sinks because, in addition to capturing atmospheric CO[sub.2] for biomass production, they produce resin (resin concentration in C: 77.17% w/w), contributing further to the mitigation of the greenhouse effect. Greece until the 1970s was considered one of the main resin-producing countries of Europe, due to the quantity and quality of resin products collected from natural populations mainly of Pinus halepensis Mill. Previous and current research has shown that resin production is a genetically controlled trait (h[sup.2] > 0.70) that exhibits great variability among trees (resin 0.5-33.0 kg per tree and year). The above led to the genetic selection of P. halepensis genotypes with constant over time high resin yields (≥20 kg per tree and year) and consequently greater atmospheric CO[sub.2] sequestration for more effective counteracting climate change but also for economic reasons for the benefit of resin producers. These high-yielding genotypes were cloned through grafting on P. brutia rootstocks and became potential trees for establishing commercial pine plantations. Thus, one hectare of commercial plantation of 500 P. halepensis trees, with a resin yield of 20 kg per tree, is expected to sequester 28.31 tn CO[sub.2] per year (instead of 2.82 tn of CO[sub.2] per year of a natural stand of 400 P. halepensis trees based on a resin yield of 2.5 kg per tree), at the productive age of 25 years. In this case, commercial plantations with improved genotypes of P. halepensis have great potential not only in mitigating the concentration of CO[sub.2] in the atmosphere, but also in restoring degraded marginal areas and arid soils, and at the same time can offer social and economic benefits to the local communities.