Qualidade fisiológica e sanitária de sementes de trigo inoculadas com trichoderma asperelloides e azospirillum brasilense

Abstract

Seed quality is essential for the good development of wheat crops in the field. This takes into account physiological and sanitary quality. To ensure these requirements, fundamental techniques and strategies are used, such as seed treatment, to control pathogens and promote initial plant vigor. Therefore, this study aimed to evaluate the effect of inoculation and co-inoculation of Trichoderma asperelloides and Azospirillum brasilense on germination, initial seedling development, and seed sanity of wheat, cultivar TBIO Motriz. The experiment was conducted at the Federal University of the Southern Frontier – Erechim Campus/RS, between July and September 2024. Germination and vigor tests were performed, in which seedling length was especially evaluated (in the laboratory and in the greenhouse), and sanity tests to verify fungal infection. The tests were developed to verify the effects of six treatments, namely: T1 = control: treatment-free; T2 = Trichoderma asperelloides (Strain MMBF 94/17); T3 = Azospirillum brasilense (Strain AbV5); T4 = Trichoderma asperelloides + Azospirillum brasilense; T5 = Chemical fungicide (pyraclostrobin + thiophanate-methyl + fipronil); and T6 = Trichoderma asperelloides + Azospirillum brasilense + fungicide chemical. Germination and seedling development in the greenhouse were not stimulated by the microbiologicals. In the laboratory, inoculation and co-inoculation reduced the initial seedling development, resulting in smaller seedlings, with a smaller root system. The use of T. asperelloides contributed to reducing infection by Fusarium spp.. Both microbiologicals, when inoculated, co-inoculated or associated with the chemical, reduced the percentage of infection by Penicillium spp. and Aspergillus spp.. Therefore, germination of wheat seeds is not stimulated by T. asperelloides and A. brasilense. In the laboratory, negative effects are observed in the initial development of seedlings, which is not repeated in the greenhouse. The sanitary conditions of the seeds are improved with inoculation and/or co-inoculation with T. asperelloides and A. brasilense.