Methodological Proposal, Based On Climate Groups, For Subsidizing Conservation And Genetic Improvement Of Yerba Mate In Southern Brazil

In addition to interfering with plant phenotype, climate acts as a major selective force that affects the plant's genotype and shapes genetic variation between populations. Thus, it should be considered when exploring this genetic variability in conservation and breeding programs. The aim of this work was to determine differences between specific climates where yerba mate occurs naturally in southern Brazil. A database of 195 natural occurrences of yerba mate was set up. These data was applied to multivariate analysis, georeferencing and modelling. Four climatic groups were obtained using eleven climatic parameters in addition to altitude. Although these groups feature spatial geographic contiguity, it was found that yerba mate occurs in several lithologic substrates, in different ecosystems (Mixed Ombrophylous Forest, Ombrophylous Dense Montane Forest, Deciduous and Semi-deciduous Seasonal Forest, Atlantic Forest biome and in the Pampa biome). This adaptation indicates a wide adaptive plasticity of yerba mate, much larger than that of Araucaria, which is a species that occurs together with yerba mate in many ecosystems. Isolated groups can be used in genetic studies to check whether populations are also genetically distinct. The output of this study may be used to support breeding and conservation programs, for current and for future use, considering the climatic changes and the anthropic pressures.