Hudson Wallace Pereira de Carvalho.

Este projeto irá criar e avaliar uma bibliotecaespectral de solos com dados de sensores de espectroscopia de raios X (XRF) e atributos chave de fertilidadede solos do estado de São Paulo. Três questões que compreendem o estado da arte para bibliotecas espectraisde sensores XRF serão respondidas, são elas: (i) qual é a melhor estratégia para calibrar modelos preditivoscom bibliotecas espectrais regionais de XRF?; (ii) quais atributos de solos tropicais podem ser preditos comdesempenho satisfatório ao usar bibliotecas espectrais regionais de sensores XRF?; (iii) a associação dabiblioteca espectral regional com modelos não lineares usando Random Forest (RF) permite previsõesmelhores do que modelos lineares de regressão por mínimos quadrados parciais (PLSR)?

Auxílio Regular FAPESP, processo 2022/14816-1

Programa Nova Geração de Pesquisadores FAPESP, processo: 22/03160-8

Auxílio Regular FAPESP, processo 2022/11773-0

JP Fase 2 FAPESP, processo 2021/06552-1

Several studies demonstrate that calcium (Ca) presents low mobility in the phloem, hence it is supplied to plant tissues mainly by the xylem. Since transpiration is the driving force of the xylem flow, Ca supply can be compromised in organs, such as fruits, which have low transpiration rate. Low productivity as well as disorders in fruits, such as apical rot, bitter pit, wilt and reduced shelf life are associated with Ca deficiency. The literature shows that the application of Ca-based foliar fertilizers, or even fruit treatment, can prevent these problems. Conversely, this same literature lacks information about the influence of Ca sources on the rate of leaf absorption and translocation. Likewise, little is known about how the application strategies influence Ca exports to the fruits. Compared with radioisotopes, X-ray fluorescence spectrometry emerges as a simpler, cheaper, and safer alternative that allows monitoring the movement of nutrients in plant tissues. This project aims at employing X-ray fluorescence to determine the absorption and translocation rates of Ca sources applied via foliar treatment. We will test CaCl2, the most common source reported in the literature, as well as chelated Ca with citrate and EDTA. To increase the sensitivity of X-ray fluorescence, strontium (Sr) will be spiked to these sources. Tomato (Solanum lycopersicum) was chosen as model plant for the study. The source of Ca with the greatest translocation capacity in the phloem will be selected in a next phase of the study, evaluating the splitting effects of the application on the productivity and quality of the fruits. The spatial distribution of Ca in the fruits will be measured by X-ray fluorescence mapping. Finally, the mass balance of Ca/Sr foliar applied shall determine the export efficiency of the treatments from the treated leaves to the drain organs. From plant physiology/nutrition standing point, the major expected outputs are: 1) contribute to the understanding of the Ca movement limitation in the phloem; 2) Potential to identify sources with greater mobility than CaCl2; 3) Demonstrate if the application strategies are able to increase the export efficiency of Ca from foliar fertilizers to fruits. Finally, the project also has the aspiration of consolidating X-ray fluorescence spectrometry in plant studies among researchers, and also disseminating foliar nutrition technology to producers.

PIPE Fase 1 FAPESP, 2018/22636-8

Projeto Temático FAPESP, 2019/26042-8

Auxílio Regular FAPESP, processo 2018/13139-0

Auxilio Regular FAPESP, processo 2017/25566-8

Auxílio Regular FAPESP, processo 2016/09660-1

Cooperation with Prof. Davide Mathia at University of Bath

Projeto USP-Santander ?Novos docentes, novas parecerias internacionais?

Equipamento Multi usuário FAPESP: Sistema de micro fluorescência de raios X

Projeto JP FAPESP que busca investigar a absorção, transporte e biotransformação de nanomateriais por plantas.