Effect on Physiological Growth and Water Utilization of Rice under Different Varieties and Irrigation Modes

Different rice varieties and irrigation modes could affect water consumption of rice, which in turn could affect field water utilization.This study conducted experimental research on physiological indicators of rice growth and water utilization efficiency, to study their inner relationship under different rice varieties and irrigation modes.The results showed that, the effect of rice variety on water consumption was not significant (P>0.05),while it was obviously higher for conventional irrigation rather than that for water-saving irrigation modes.The effect of rice variety on rice height was extremely significant (P≤0.01),while the irrigation method effect was not significant (P>0.05).Hybrid rice showed a better growth status at late growth stage of rice leaves and root activity, which was favorable for nutrient absorption and high rice production.The average yield of hybrid rice was 31.9% higher than that of conventional single-season rice.The average WUE I and WUE ET under conventional singleseason rice was 20.3% and 22.7% lower than that under hybrid rice.The effect of rice variety on yield and WUE both showed significant difference (P≤0.05).After principal component analysis on different rice varieties, there were 2 and 3 principal components for single-season rice and hybrid rice respectively.Path relationship on water demand-comsumption-yield showed that field leakage had a significant positive impact on irrigation amount, water consumption, water utilization efficiency, and yield, while it had a significant negative impact on evapotranspiration.Irrigation amount had a significant negative impact on water consumption and water utilization efficiency of irrigation.