Phosphorus mobilization from organic sources by eucalypt roots and soil microbiota: implications for phosphate nutrition

• Grant number: 21/02939-9
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2021
• End date: January 31, 2024
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Sara Adrian Lopez de Andrade
• Grantee: Sara Adrian Lopez de Andrade
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated researchers: Adriana Parada Dias da Silveira ; Claudio Francisco Tormena ; Eiko Eurya Kuramae ; Paulo Mazzafera
• Associated scholarship(s): 22/04909-2 - Phosphorus mobilization from organic sources by eucalypt roots and soil microbiota: implications for phosphate nutrition, BP.TT; 21/10531-0 - Phosphorus mobilization from organic sources by eucalypt roots and soil microbiota: implications for phosphate nutrition, BP.TT

Abstract

Soil phosphorus (P) is predominantly in non-soluble and/or organic forms, which contributes to its low availability, mainly in tropical and subtropical soils. Under these conditions, plants, their symbionts and soil microbiota are key in the cycling and mobilization of P. The adaptation of plants to P limiting conditions can be reflected in the ability to acquire P from less available forms, such as those present in organic P (Po) compounds, which is a nutritional strategy in poor P soil and where Po may be relevant to supply P to the plant. The secretion of different types of phosphatases and phytases by roots and their symbionts can be related to the ability of roots to mobilize Po compounds. The general objective of this project is to study the relationship between Po, root enzymatic activity of eucalyptus species (Eucalyptus globulus and E. grandis) and their interaction with arbuscular mycorrhizal fungi (AMF) and soil microorganisms in the phosphate nutrition of plants. The study will follow two approaches, the first by assessing the activity of exoenzymes and exudates of root origin and the extraradicular mycelium of AMF related to the mobilization of Po sources such as phytate, ATP, RNA, glucose-6-phosphate and bacterial necromass. In the second approach, a microcosm experiment will be carried out to assess the interrelation between soil microbiota and Po cycling in soils collected from areas under different vegetation cover, eucalypt plantation and fallow, and their effects on the two eucalyptus species phosphate nutrition. Soil Po will be characterized by 31P-NMR, the microbial activity related to P cycling by determining the abundance of P-related genes sucha as phoD, phoA, bpp, and the composition of microbial communities, by next generation sequencing, related to P-cycling activities. The project will bring evidence on the ability of eucalyptus species to use P from organic sources, what is their ability to produce enzymes involved in the mobilization of P from different organic compounds and what is the role of arbuscular mycorrhizal symbiosis in this process. The relevance of soil microbiota in P cycling and its relationship with phosphate nutrition of plants could be better understood by bringing information with implications for understanding P cycling and availability in soils from subtropical regions. (AU)