Mycorrhizal and trichoderma harzanium inoculation enhance bean growth and protection against phaeoisariopsis griseola in southern cameroonian soil
Résumé
Arbuscular mycorrhizal fungi (AMF) and members of Trichoderma genus colonize and protect plant roots against pathogen infections via different induced defense mechanisms, among other the enhancement of biosynthesis of secondary metabolites and low molecular weight compounds.
We reported here the results from a field study on the influences of simultaneous inoculation of AMF and Trichoderma harzanium on common bean crop grown under the field condition of southern Cameroon. A disease-sensitive and a disease-resistant bean genotypes were sown and harvest at mid-flowering and at maturity stages and analyzed for biomass Dry matter production, root length colonized by AMF and the concentrations of P, N, amino acids and phenolic determined. The disease severity caused by Phaeoisariopsis griseola was further assessed.
The growth of the disease-resistant bean genotype was notably increased following AMF inoculation. The inoculation with co-inoculation with AMF and Trichoderma resulted in remarkably testing effects on plant biomass N and P concentrations, root length colonization by AMF, and the incidence of foliar diseases. The Trichoderma inoculation particularly resulted in increased root length colonization by AMF, N and P concentrations and the foliar diseases incidences.
Significant genotypic variation for the amino acid, proline, and phenol synthesis was noted and bean-resistant genotype resulted in higher concentrations of molecular weight compounds than the sensitive one. The interactions between the Trichoderma and AMF inoculation were noteworthy with regards to N and P accumulation and diseases incidences, respectively.
The overall plant induced mechanisms for the common bean crop to cope with diseases and achieve superior yields are discussed to support breeding program aiming at developing disease-resistant and high yield bean yield under stressing environmental conditions of small-scale farming production systems of Cameroon.