Inoculation Strategies of Lasiodiplodia theobromae and Interaction with Ceratocystis fimbriata in Tectona grandis.
Forest phytopathology; Plant-pathogen interaction; Inoculation methods
Teak (Tectona grandis L. f.) stands out as one of the most economically relevant tropical forest species in the world scenario, due to the high quality and added value of its wood. However, the expansion of commercial plantations has favored the emergence of phytosanitary problems, especially diseases caused by fungi, which compromise the development of plants and the quality of wood. Among the main pathogens associated with the crop are Lasiodiplodia theobromae, the causal agent of teak canker, and Ceratocystis fimbriata, responsible for Ceratocystis wilt, both considered limiting the sustainability of plantations. In this context, the present work aims to evaluate the efficiency of different inoculation methods for L. theobromae and to understand the effects of the interaction between L. theobromae and C. fimbriata in young seedlings of T. grandis, in addition to analyzing physiological responses of plants by leaf spectrometry. For this, two experiments will be conducted, experiment 1 – different inoculation methods for L. theobromae and experiment 2 – interaction between L. theobromae and C. fimbriata, both experiments in a protected environment, using clonal teak seedlings and fungal isolates from commercial plantations. The inoculation methods to be evaluated are: mycelium disc, superficial scratch on the stem and root cutting followed by watering with suspension. The severity of the disease will be evaluated at 15, 30 and 45 days after inoculation, by measuring the length and area of the internal lesions on the stem, in addition to analyzing the spectral reflectance indices of the leaves. The data will be submitted to analysis of variance, with comparison of means by Tukey's test at 5% probability. It is expected that the inoculation methods present significant differences in the efficiency and severity of the diseases, as well as that the interaction between the pathogens will intensify the v symptoms and physiological impairment of the plants. The results should contribute to the improvement of inoculation protocols,to understand the plant-pathogen interaction and to support genetic improvement programs and phytosanitary management of teak.