Molecular identification and growth rate of native strains of Trichoderma spp. isolated from the Northern Region of Paraguay

Abstract

The fungi of the genus Trichoderma, due to its cosmopolitan distribution, rapid growth and abundant production of spores, are ideal candidates for applications in biological control programs in different habitats. With the objective of molecularly identify strains of Trichoderma spp. and evaluate the in vitro effect of temperature on growth and appearance of colonies, an investigation was conducted at the Laboratory of Plant Pathology Research Capitan Miranda Investigation Center (CICM) belonging to the Paraguayan Institute of Agricultural Technology (IPTA), located in the district of Capitán Miranda, Itapúa Department, Paraguay. The growth rate and colony appearance was determined by culturing on potato dextrose agar at 25, 28 and 31 ° C and the molecular identification at the species level was performed by analyzing the nucleotide sequences performed in Blastn. Of the seven strains, six (MS9, MS10, MS12, MS15, MS16 and MS19) correspond to T. asperellum and the remaining (MS28) to T. erinaceum with an identity of 100%. The optimum growth temperature for all strains tested was 25 to 28 ° C (fast growing). The strain T. asperelleum obtained the highest growth rate being MS10 - MS15 the highest growth rate at 25 ° C (24.19 and 23.85 mm.día-1), MS16 - MS10 at 28 ° C obtained a CT 26.39 and 26.11 mm.día-1 and 31 ° C the strains MS19 - MS9 had a CT scan of 7.05 and 6.78 mm.día-1.