Calibrated varieties

This section combines the outcomes of calibrations and validations of ORYZA2000 from published and unpublished books, papers, theses, and reports. These calibration and validation studies were conducted for varieties IR72, IR64, IR58, PAO (K67), YOU512, YOU501, XD90247, HD297, Takanari, Nipponbare, and Wuxiangjing9 in China, Indonesia, Japan, the Philippines, and Thailand. Users of ORYZA2000 and readers can get quantifying information on how well ORYZA2000 estimates the following variables: 

·     ponded water depth; 

·     soil water content; 

·     seasonal variations of leaf area index (LAI), aboveground biomass components, and plant nitrogen; 

·     final biomass and grain yield; and 

·     the effects of soil-water and management practices on these variables.

In this section, the conditions of experimental sites, field experiments, and simulations are described based on variety-environment (location) groups. Model evaluation results of each group are presented in graphs and statistical tables. This report also provides additional information on methods of calibration, validation, and data collection of ORYZA2000 that was not discussed in earlier publications. For details, users should refer to sections 7 and 8 of the book ORYZA2000: modeling lowland rice (Bouman et al 2001), and section 6 of tutorial document “ORYZA2000: modeling lowland rice, handouts and references” (Bouman and van Laar 2004). This section introduces methodology that was not covered in those two documents. In addition, other experimental methods are described in individual studies.

Here is a list of all contributors for the calibration and validation of ORYZA2000.


Calibrated varieties for ORYZA2000


·     IR72 (IRRI, Philippines)

This validation study used data from field experiments conducted at the International Rice Research Institute (IRRI farm, Field K3, 14.22°N, 121.25°E, 23 m asl) in Los Baños, Philippines, in the dry seasons of 1992-93 and wet seasons of 1991-92. 

Click HERE to read more about IR72 (IRRI, Philippines) experiment.

Click HERE to download the data.



·     IR58 (IRRI, Philippines) 

This validation study used data from field experiments conducted at the International Rice Research Institute (IRRI farm, Field K3, 14.22°N, 121.25°E, 23 m asl) in Los Baños, Philippines, in the dry seasons of 1992-93 and wet seasons of 1991-92.Based on historical (1953-96) records, the rainy season in Jakenan usually starts in October, peaks in January, and ends in May or June. Average annual rainfall is 1,550 mm, with 1,060 mm falling from November to March. Mean daily solar radiation is low (13 MJ m–2 d–1) in January and high (18 MJ m–2 d–1) in September. Average maximum temperature is 31.7 °C and average minimum temperature is 23.5 °C.

Click HERE to read more about IR58 (IRRI, Philippines) experiment.



·     IR64 (Indonesia) 

The field experiments were conducted at the Jakenan Experiment Station (6°45S, 111°10E, 7 m above sea level), representative of about 150,000 ha of rainfed lowland area in Central Java (Mamaril et al 1995). The landscape is undulating and the soil is Tropaqualf. 

Click HERE to read more about IR64 (Indonesia) experiment. 



·     APO (IRRI, Philippines)

This validation study used data from field experiments of continuously flooded, flooded, nonflooded, and aerobic rice at Los Baños, Philippines (14°18N, 121°25E). The experiments included two levels of nitrogen (N), a control, and a supposedly optimum agronomic level.

Click HERE to read more about APO (IRRI, Philippines) experiment.



·     Hybrid - 2YOU501 and 2YOU725 (China)

This validation study used data from one field experiment on continuously submerged and submerged-nonsubmerged fields at Tuanlin, Hubei Province, China (30°52N, 112°11E). The experiments included two levels of nitrogen (N), a control, and a supposedly optimum agronomic level.

Click HERE to read more about Hybrid (2YOU501 and 2 YOU725) (China) experiment.




·     XD90247 and HD297 (Kaifeng, China) 


This experiment was conducted near Kaifeng, Henan Province, China, in the summer seasons of 2001-04. Average rainfall in the area is 600 mm, of which 70–80% falls in the crop growth period of May-September. The experiment in 2001 was conducted on a loam soil in a puddled lowland rice environment at Gaozhai Village (3482N, 11451E; 69 m altitude). From 2002 to 2004, the experiments were conducted on a sandy loam soil in an upland crop area in Panlou Village (3478N, 11452E; 68 m altitude).

Click HERE to read more about XD90247 and HD297 (Kaifeng, China) experiment.




·     HD297 - aerobic rice (Beijing, China) 


Field experiments were conducted at the Changping Experiment Station (40°02N, 116°10E; altitude of 43 m) of China Agricultural University in Beijing from 2002 to 2004. The fields used in 2002 and 2004 were the same; an adjacent field was used in 2003. Both fields were used for seed production of wheat and maize in the five preceding years. The soil of the fields was a sandy soil (Fluvisol) derived from river sediments. Physical and chemical properties of the soils are given in Table 1.  In all years, the groundwater table was deeper than 20 m.

Click HERE to read more about HD297 (aerobic rice) (Beijing, China) experiment.




·     Wuxiangjing9 (China)

Two field experiments with summer rice (i.e., long-duration varieties grown from late spring to early autumn) were carried out in 2001-02 at the Jiangpu experiment station of Nanjing Agricultural University (118.78°E, 32.04°N).

Click HERE to read more about Wuxiangjing9 (China) experiment.




·     Indica - IR72, Japonica - Nipponbare, and Indica x Japonica - Takanari 

      (China, Japan, and Thailand)

Field experiments were carried out at Iwate (39°21N, 141°13E), Nagano (35°51N, 138°10E), Shimane (35°30N, 132°36E), and Kyoto (35°01N, 135°45E) in Japan; at Nanjing (3.2°06N, 118°45E) and Taoyuan (26°16N, 101°02E) Yunnan Province in China; and at Chiangmai (18°47N, 98°59E) and Ubon Ratchathani (15°20N, 104°52E) in Thailand.

Click HERE to read more about the China, Japan and Thailand experiments.