A yield gap indicator for rice cold damages: application to the MARS database R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 Roberto Confalonieri, Fabio Micale, Giampiero Genovese

Court of Auditors Economic and Social Committee Committee of the Regions Council of Ministers European Parliament European Commission Court of Justice IPSC Commissioner for Research EI IES ITU IRMM IPTS IHCP DG ENTR DG ENV DG RTD DG INFSO JRC DG SANCO EUROSTAT DG RELEX ECHO DG AGRI AGRIFISH Unit (MARS STAT) AGRIFISH Unit (MARS STAT) DG MARS-STAT section in EC Context R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

Mars Crops Yield Forecasting System MeteorologicalMonitoring Crop Model Statistical Scenarios Analysis VegetationMonitoring R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 EC crop yield forecasting system

R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 Calibration of WOFOST for rice.1 (Confalonieri and Bocchi, European Journal of Agronomy. Paper in press) 3 groups of rice varieties: Japonica typeearlyJE medium lateJM Indica type I

R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 Calibration of WOFOST for rice.2 Validation results - an example: JE varieties Calibration results – an example: JM varieties

R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 Hp: Correspondence of model overestimations and years where high sterility verified High sterility Low sterility Calibration of WOFOST for rice.3

Calibration of WOFOST for rice.4 After the calibration of crop model parameters, WOFOST was generally able to accurately simulate rice growth and development but for some years, we noticed significant overestimation. During these years, particular meteorological conditions occurred: Cold air irruptions during the pre-flowering period R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

Cold air irruptions in Northern Italy Although the summer presents typical Mediterranean features, the proximity to the arctic area, may sometimes expose to summer cold air irruptions able to influence the young panicle development The induced spikelet sterility may, in some cases, reach values between % depending on the different varieties sensitivity. They do not cause higher sterility percentages because of their duration: usually no more than 2-3 days R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

Cold air irruptions in Northern Italy The last important episode occurred on 12 July 2000 minimum air temperature = 7-8°C (sterility = 25-50%) R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

Cold air irruptions in Northern Italy The frequency is about 1 event every 5-6 years (minimum air temperature during the period ) R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

At the moment, simulation models... Actually crop growth models used for rice simulations do not consider yield losses caused by cold damages during the pre- flowering period and this may lead, in some cases, to enormous yield overestimations. In some years (when particular meteorological conditions occur), models have to be considered inadequate tools. Crop modellers are working to improve the simulation of physiological processes which are already rather well simulated but at the moment they are not including in their models processes which have a big influence on yield and which are still considered unrelated to crop simulators. R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

…WARM

R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 In this presentation WARM features and peculiarities will be briefly exposed Simulation of the yield gap caused by cold air irruptions during the pre-flowering period for: 4 years (1991, 1993, 1994, 2000) 11 grids (50×50 km) north Italian Sowing date: 27 April High sensitive rice variety

WARM Crop growth model The MARS database TRIS (floodwater effect on T) STEFI (spikelet sterility model) ???

T.RI.S. (Confalonieri et al., Ecological Modelling, 183, ) TRIS is a mechanistic model funded on the resolution of the energy balance equation adopting as storage term the heat accumulation into the water. It needs as input only maximum and minimum air daily temperatures. If other data (e.g. global solar radiation) are available, the model can use measured values instead of estimated ones. It computes water temperature and 10 series of air temperatures (one for each 10cm air layer starting from the water surface) R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

T.RI.S. – some results Surface water temperature for the second decade of May, June, July and August (Opera (MI), 2002) R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

The model for sterility induced by low temperatures is based on two principles: daily stress inducing sterility is computed adding hourly differences between a threshold temperature and hourly temperatures simulated by TRIS at the height of the developing panicle total stress is obtained by adding daily values weighted by a factor (bell factor) which represents the different plant sensitivity during the panicle initiation – heading period STE.FI. – a model for spikelet sterility R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

bell factor... STE.FI. – a model for spikelet sterility hourly stresses R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

STE.FI. – the bell factor γ δ is used to fix the maximum value to 1 γ R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

CGMS WARM - Results.1 (high observed sterility: 1993, 2000) R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005

CGMS WARM - Results.2 (low observed sterility: 1991, 1994)

R. Confalonieri – A yield gap indicator for rice cold damages - Bologna, 15 June 2005 Conclusions: The yield gap computed basing on the spikelet sterility and on the influence of floodwater on vertical thermal profile has shown to be a powerful tool for the improvement of the precision of rice yield forecasts All the aspects with a high influence on yield must be taken into account and this is why other modules are currently under development (e.g. for blast) It is necessary that all the developed modules are compatible with the MARS database (only the already available input variable collected at similar spatial scale)