Effects Of Water Stress And Planting Model On Root-Sourced Signal And Capability Of Competition And Yield In Wheat

The chlorophyll fluorescence, behaviors of root-sourced signal and the capability of competition and saving water was measured under different water stress and planting model in two varieties of wheat. The adaptation mechanism of water stress and competitive strategy of two varieties wheat was studied in the different planting model. There are some suggestions for wheat drought resistance breeding and high efficient use of water resource. The main results are as follows:1.The chlorophyll fluorescence kinetics parameters of two varieties wheat that were dealed with water stress in monoculture and mixed-cropping were measured in its anthesis by Imaging-PAM chlorophyll fluorometer in this study. The results showed that under water stress and monoculture, the PSâ…¡central reacting region and photochemistry efficiency of Changwu135 were higher than that of Pingliang40, the net photosynthesis rate and leaf water use efficiency of Changwu135 were still superior maintenance under water-stress. Under water-stress and mix-cropping, the PSâ…¡central reacting region of Changwu135 was suffer a certain extent injuries, the leaf photochemistry efficiency and the net photosynthesis rate were observably descended.2. Compares of the feature of root-sourced signals of winter wheat (Triticum aestivum L. cv'Changwu135'and'Pingliang 40') grown during progressive soil drying were studied. Winter wheat grown in the flowerpots was transferred to environmental controlled glasshouse everyday. In monoculture and mixed-culture, the threshold range of Changwu135 ranged from62.1%-49.6% and 65.4%-48.7% FWC(Field water capacity)has a wider threshold range. Conversely, Pingliang40 kept a narrower threshold range from 53.3%-50% and 55.34%-52.1% FWC. Water supply was ceased simultaneously and the plants in pot were allowed to dry naturally. The results showed that the survival day for Pingliang40 was the lower, generally 6.7 and 8.2 days; survival time for Changwu135 was the longer, ranging from7.8 and 9.3days, in monoculture and mixed-culture.3. Compares of competitive ability and yield of two wheat cultivars, the result showed that water-consumption of Pingliang 40 was significant higher than Changwu135. Under monoculture and drought treatment, water use efficiency, yields and harvest index of...