Fig 1.
Correlation analysis between rice yields and climate variables.
(A) The spring crop rice; (B) The autumn crop rice. * denotes a significant difference of correlation between two variables (p-value < 0.05). Note: temp: accumulated temperature (°C); gdd: growth degree days; prcp: accumulated precipitation (mm); rad: accumulated radiation (MJ/m2); temp.ini: accumulated temperature in initial growth stage (°C); temp.veg: accumulated temperature in vegetative growth stage (°C); temp.flo: accumulated temperature in flowering growth stage (°C); gdd.ini: growth degree days in initial growth stage; gdd.veg: growth degree days in vegetative growth stage; gdd.flo: growth degree days in flowering growth stage.
Table 1.
Genotype parameters of the three rice cultivars.
Fig 2.
Relationships between the measured and simulated values.
(A) Rice cultivar TK9; (B) Rice cultivar TNG67; (C) Rice cultivar TCS10. The dashed lines refer to the 1:1 lines.
Table 2.
Simulated values of three rice cultivars yield under different irrigation amount based on two water saving scenarios with the yield ratio of water saving cultivation to auto-irrigated cultivation in brackets in different seasons.
Fig 3.
Scatter plots of rice yields ratio of water saving cultivation to auto-irrigated cultivation versus water saving proportion, obtained using the linear (solid), quadratic (dashed), cubic (dotted), and logistic (dot dashed) models to fit the three rice cultivars simulation data sets in different seasons and precipitation.
(A) TK9 water saving irrigation models; (B) TK9 sensitive growth stage irrigation models; (C) TNG67 water saving irrigation models; (D) TNG67 sensitive growth stage irrigation models; (E) TCS10 water saving irrigation models; (F) TCS10 sensitive growth stage irrigation models.
Fig 4.
Scatter plots of rice yield versus water saving proportion, obtained using the model which is selected by AIC criteria to fit the three rice cultivars simulation data sets in different seasons and precipitation.
(A) TK9 water saving irrigation models; (B) TK9 sensitive growth stage irrigation models; (C) TNG67 water saving irrigation models; (D) TNG67 sensitive growth stage irrigation models; (E) TCS10 water saving irrigation models; (F) TCS10 sensitive growth stage irrigation models.
Table 3.
The results of using the model which is used to fit two water saving irrigation scenarios data sets to predict the water saving percentage required to maintain 90% yield of three rice cultivars in different seasons.