02096naa a2200277 a 450000100080000000500110000800800410001902400480006010000210010824501310012926000090026052012650026965000120153465000150154665000240156165000170158565000260160265300140162870000180164270000210166070000180168170000180169970000210171770000170173877300630175521502452023-07-07       2022    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1093/forsci/fxac0282DOI1 aAGUIAR, N. S. de  aProductivity of clonal Ilex paraguariensis genotypes in a semi-hydroponic system Is reduced by shading.h[electronic resource]  c2022  aYerba mate (Ilex paraguariensis A. St.-Hil.) is a South American tree cultivated in systems with or without shading at different intensities; how- ever, there is no consensus about shading effect on leaf biomass production. Therefore, we evaluated yerba mate clones under different shading levels over one year to determine the infuence of shading and genotype on biomass production. Two yerba mate genotypes (EC22 and EC40), cultivated in a semi-hydroponic system, were subjected to fve shading levels (0%, 40%, 51%, 76%, and 82%) in a greenhouse. We determined total fresh biomass (branches and leaves) and fresh biomass of young and mature leaves on six harvests. Biomass production was infuenced by harvest season, genotype, and shading levels. Spring and summer harvests provided higher biomass production than the other seasons. EC40 genotype produced higher total fresh and young leaf biomass than EC22. Although we observed differences among genotypes and harvest seasons, shading was the factor that most infuenced biomass production. Total fresh biomass productivity was reduced 6.8 times between 0% and 82% shading for the EC40 genotype. Thus, we do not recommend high levels of shade, such as 76% and 82%, in this new yerba mate cultivation system.  aBiomass  aYerba mate  aIlex Paraguariensis  aSilvicultura  aSistema de Produção  aErva-mate1 aGABIRA, M. M.1 aTOMASI, J. de C.1 aDUARTE, M. M.1 aVIEIRA, L. M.1 aLAVORANTI, O. J.1 aWENDLING, I.  tForest Sciencegv. 68, n. 5-6, p. 540?547, Oct./Dec. 2022.