Growth promotion of Pinus radiata seedlings by soil inoculation and seed pretreatment with the biological control agent Clonostachys rosea. ABSTRACT Twenty-one Clonostachys rosea strains, previously selected by its biocontrol activity higher than 80% against Fusarium circinatum, were evaluated for its ability to promote growth of Pinus radiata seedlings on natural substrate. Stem height, root length, dry weight of stem and roots, and ectomycorrhization were measured at 102 days after seeding. The results showed significant differences between some of the tested C. rosea strains when compared to the controls, showing increases for plant height of 25%, dry stem mass of 37%, root length of 13.5%, dry root mass of 20.5% and ectomycorrhization of 55% when compared to their respective controls, demonstrating a possible dual use of these strains for both plant protection and increased biomass of P. radiata.. https://bibliotecadigital.infor.cl/handle/20.500.12220/29862