Standardization of analytical methodologies for biofertilizers effectiveness verification

• Grant number: 18/25956-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: July 01, 2019
• End date: September 30, 2019
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Marcos Yassuo Kamogawa
• Grantee: Milton Katsumi Sasaki
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

The lack of improved protocols for the field application of biofertilizers is a limiting factor for its worldwide large-scale use. In Brazil, biofertilizers are evaluated considering different soil attributes and/or test-plants, in other words, there is no standardization in these evaluations. Despite the growing need for new technologies in agriculture, as well as increased productivity, there seems to be no definite protocol for the biofertilizers efficacy evaluation. In this way, this project aims at obtaining an analytical protocol capable of proving, in accordance with current Brazilian legislation, the efficiency of products that present bioactivity and can be classified as biofertilizers. The protocol, proposed at the end of this project, should subsidize the standardization of evaluations related to the efficiency of biofertilizers, and may be submitted to the official bodies as a proposal for an official procedure. Simple and robust analytical procedures for the analysis of commercial products containing e.g. humic substances, amino acids and extracts of plants and algae, for the cultivation of soybeans will be evaluated. These procedures should be capable and sufficient to evaluate the characteristics of growth, ontogeny, biochemical variables and response to abiotic stresses. The effect on seed germination, seedling vigor, root development and yield will be evaluated by applying the products via seed treatment. Regarding the biochemical variables, enzymatic studies in soil, including ²-glucosidase, acid phosphatase and arylsulfatase will be performed, these enzymes were selected due to their roles in carbon, phosphorus and sulfur cycles, respectively. The effect on stress response will be evaluated by chlorophyll a fluorescence, a widely used strategy to non-invasively monitoring photosynthetic performance of plants. The evaluation of the nutritional status will be based on the mineral composition of the plants. Due to the multidisciplinary nature, specialists in plant nutrition, fertilizers and fertilization, microbiology and chemistry will support this project.