Development of a rice growth model for early warning and decision support systems

Agriculture and Food Research Organization (NARO) Japan National Agricultural Research Center (NARC)

Agroinformatics DivisionHiroe Yoshida, Kou Nakazono, Hiroyuki Ohno and Hiroshi

Nakagawa

Background　 Crop growth simulation models for rice have played important

roles to help understand its yield responses to various environmental conditions.

(Kropff et al., 1994; Horie et al., 1995; Bouman et al., 2001)

　　　　　・ Evaluate plant ideotype 　　　　　　　 ・ Predict potential yield ・ Asses the effect of climate change on crop performance ・ Verify physiological hypotheses for further experimental research

The crop growth model has also been utilized as a part of knowledge based decision support systems. (e.g. CERES series in DSSAT)

Further development of early warning and decision support systems will be synchronized with that of crop growth simulation model.

・ Transplanting date・ Cultivar・ Management plan

Early Warning and Decision Support System

Decision making!

Predict crop productivity based on crop model simulations for years 　 (risk analysis)

Sound early warning based on physiological knowledge and weather system

Propose management strategies in response to the early warning

Decision making!

New needs in crop

modeling

・ Water management・ Amount of top-dressing N fertilizer

Contents

（１） Rice Management in Japan -from statistical data

（２） Development of a rice growth model for early warning and decision support systems

　　 Targets in process-based rice model

（１） Rice Management in Japan

（２） Development of a rice growth model for early warning and decision support systems

Crop response to N application

Yield

Biomass

LAI

Organ N

N

uptake

Spikelet

#

DVI

Targets in process-based rice model Brown Rice Yield 　 ←　 Spikelet # , Grain filling ratio Appearance Quality 　←　 N and storage starch

concentration Food Quality 　　 　　 ←　 Protein content in brown rice

N% in brown rice (protein concentration)

Dynamics of storage starch accumulation

Vegetative Tissues(V)

Storage starch (ST)

Storage starch accumulation

Vegetative tissue growth Grain Yield (Y)

Root

Photosynthesis

Sugar (Su)

Maintenance respiration

Grain growth

Vegetative tissue N (NVT) (leaf N + stem N)

Vegetative tissue N accumulation

Grain N (NY)

N uptake

Npool (leaf N + stem N)

Grain N accumulation

Senescence

Recover

Translocation

Root growth

ND

Npool accumulation

Translocation

Attainable Yield

Spikelet sterility

Spikelet #

Differentiation

Degeneration

Development

DVI

Root system development

Root system

Indigenous supply

Soil mineral N

fertilization

Loss

Biomass growth

Yield formation

Plant N dynamics

Plant N uptake

Phenological development

Spikelet number

Expansion

LAI

LAI development

Senescence

Yoshida and Horie (2010) FCR 117, 122-130.

Fig ． Decreased appearance quality of rice ‘Hatsuboshi’ grown under high air temperature condition

Thank you!