*This information is provided by Prof. Kaoru Kitajima in the Division of Forest and Biomaterials Science.

We are pleased to welcome Dr. Tovohery Rakotoson, University of Antananarivo (Madagascar), who ireceived Japan International Award for Young Agricultural Researchers (Japan Award) for this year (https://www.jircas.go.jp/en/event/2022/e20221122_japanaward) this year. His talk will be about phosphorus deficiency in rice in sub-Saharan Africa, which is an important issue to address for achieving SDGs. Please come to W214 for on-site participation. Online participation is also available, so if you wish to attend the lecture, please register at the FEFCO website at the following webpage.   http://www.bluemoon.kais.kyoto-u.ac.jp/FEFCO/

When: 16:30-17:45, Friday 25 November, 2022
Where: Room W-214, Faculty of Agriculture Building (農学部総合館 W-214)
Name: Tovohery Rakotoson, Ph D
Position: Research Fellow (Laboratory of RadioIsotope, University of Antananarivo), Systems Agronomy Consultant (AfricaRice)
Title: Addressing phosphorus deficiency in rice in sub-Saharan Africa

Flyer

Abstract
Phosphorus (P) deficiency is a major limiting factor for rice production in sub-Saharan Africa (SSA). Our study identified that the application of organic materials such as rice straw and farmyard manure (FYM) increases P availability through microbial-mediated reduction of iron (Fe) oxides with subsequent solubilization of Fe-bound P in soils increasing P uptake and biomass of rice. The use of isotope dilution technique confirmed that FYM application enabled the use of otherwise insoluble P pools in soils and enhanced P uptake of rice plants. The effect of FYM application against P deficiency was also demonstrated on farmers’ lowlands in Madagascar with greater impact in soils with low pH and low carbon contents. The extensive survey identified that the soil P fractions in the central highlands of Madagascar are mostly insoluble forms bound to Fe and (aluminum) Al oxides. These findings should promote the locally available organic resources to more efficiently utilize insoluble P pools in soils and enhance lowland rice production in the region. We also identified that a micro-dose of NPK fertilizer applied to the nursery bed produced more vigorous seedlings, resulting in higher grain yields and higher profitability compared to the current farmers’ fertilization practice for lowland rice production in Madagascar. Our findings are relevant to integrated fertilization management using locally available organic resources and small amounts of mineral fertilizer to address the typical P-deficient soils in SSA and efficiently increase the lowland rice production in the region.

For questions, please contact Kaoru Kitajima (kitajima.kaoru.4s@kyoto-u.ac.jp)