Study On Physiological And Ecological Characteristics Of Rice Under Different Irrigation Methods

In this study, biological characteristics of rice and ecological environment characteristics of field in non-weighting lysimeters and plots were investigated under four different irrigation methods of intermittent irrigation ( B ), semi-dry cultivation (C ), dry cultivation ( D ) and continuous flooding irrigation (A) for super hybrid rice combinations of Liangyoupeijiu and Honglianyou no. 6. The results were showed as follows:①Water consumption and average consumption intensity in paddy rice under four irrigation methods were A > B > C > D, while water consumption, ratio(percentage of water consumption in one certain growth stage to that in the whole growth stage) and intensity in different stages of rice under different treatments showed a few differences. Average water consumption under flooding irrigation and intermittent irrigation reached 538.60 mm and 491.45 mm, respectively. Water use consumption under B, C, and D was 91.25%, 82.04% and 70.31% of that under A, respectively. Average water consumption intensity during the whole growth stage of rice was A > B > C > D, and the value was 5.04 mm·d^-1, 4.77 mm·d^-1,4.21 mm·d^-1 and 3.54 mm·d^-1, respectively.②Compared with under continuous flooding irrigation, photosynthetic rate, leaf area index, and water use efficiency(WUE=Pn/Tr, Pn is photosynthetic rate; Tr is leaf transpiration rate ), of rice leaves were increased while leaf transpiration rate was decreased under intermittent irrigation; water use efficiency of rice leaves under semi-dry cultivation became higher because leaf transpiration rate decreased more obvious than that of photosynthetic rate; photosynthetic rate , transpiration rate, leaf area index, and water use efficiency of rice leaves decreased under dry cultivation while leaves were senile in premature period.③Water use productiveness(percentage of yield per hectare to water consumption per hectare) and yield of rice under intermittent irrigation reached the highest and the yield traits was the best among under the four treatments; water use productiveness of rice was higher under semi - dry cultivation than under continuous flooding irrigation because water consumption decreased evidently although its yield dropped slightly; Water use productiveness and yield of rice under dry cultivation also decreased evidently. Water use productiveness under different irrigation methods was B > C> A>D. The value was 2.10±0.15Kg·m^-3, 1.78±0.04Kg·m^-3, 1.54±0.17Kg·m^-3 and 1.34±0.04Kg·m^-3, respectively. From the data above, it was clear that water use productiveness under B was 35.90% greater than that under A and 56.72% greater than that under D.④A high significant difference of the growth stage length of rice was found under...