| The experiment were carried out from 2008 to 2009 in the testing-hole at the Henan Agricultural University Science and Education Garden Area. The experiment usesd crop genetic and ecological physiological characteristics of their own, combined the temporal (different stages) and spatial alternation (in different root regions) together to form a temporal and spatial integrated control technology for active water regulation. Through the analysis of soil moisture transfer, the characteristics of growth and development, physiological and ecological effects, yield and water consumption of summer corn, this thesis systematically examines the physiological and ecological of temporal and spatial integrated control technology of summer corn. With sufficient disscussion,the conclusions are listed as follows:Under temporal and spatial alternative irrigation methods, at the end of irrigation, the trentment (T2)has the average SWC and max SWC which within the height of 15 cm and width of 55 cm, and the time of infiltration was the shortest. Because of soil water potential, increased lateral infiltration and reduced vertical infiltration at non-irrigation ditch (observation point 4), soil water content increased gradually, and finally reached equilibrium. This result demonstrates that appropriate ridge parameters (T2 treatment) can improve the soil water redistribution, so that spatial and temporal alternation of irrigation can greatly improve the water-saving irrigation efficiency.For the soil water content in summer corn's growth period, vertical changes at different levels have significant differences. There were smaller differences of soil moisture content in different levels at seedling stage, and differences gradually enlarged after jointing. The soil moisture fluctuation ranged relatively bigger of the 0 ~ 40 cm layer, 40 ~ 60 cm layer was relatively small, 60～80 cm and 80 ~ 100 cm was relatively stable. The differences were obvious for soil water content of 60～100 cm, at jointing stage, high moisture (80% of field capacity) which included T1N1, T1N2 and T1N3 three treatments have always increased continually, moderate deficit ( 65% of field capacity) which consists of T2N1, T2N2 and T2N3 showed significant downward, severe deficit (50% of field capacity) which included T3N1, T3N2 and T3N3 began an earlier decline. Under the same period of supplementary irrigation, the amount of supplementary irrigation is different, soil water content showed: N1> N2> N3, the high water> moderate deficit> Severe deficit.The process of plant height and leaf area index increased gradually with the growing process of corn, and with the reduction of the total amount of supplementary irrigation, it decreased. T1N2 treatment high moisture at jointing, moderate deficit at heading stage were the highest. Grain dry weight increased gradually in all treatments, in the period of early grain filling, the grain dry weight among different treatments has no significant difference, but with the grain filling process, the difference increases. In the same period of supplementary irrigation, the different amount of supplementary irrigation showed: the high water> moderate deficit> Severe deficit. At different stage of supplemental irrigation it showed jointing stage is better than heading stage.Value of maize leaf chlorophyll, leaf relative water content and specific leaf weight decreased gradually with the plant growth process. Among different treatments, T1N2 treatment that has high moisture at jointing, moderate deficit at heading stage were the highest. While the rest treaments decline with the decreasing of the total amount of supplementary irrigation, and under the same period of supplementary irrigation, each dealing with the enlarged extent of water deficit, the declining rate increased. MDA content in maize leaves and proline content were gradually increased with the senescence of plant, the relative conductivity of leaves were gradually reduced and changed relatively. The performance shows that T1N2 treatment which the jointing of high moisture and the heading stage of moderate deficit, MDA and proline content were smallest, while the relative conductivity was the largest. With the growth process, the difference increased between other treatments and after silking 30 days the rest of the treatments were different.Between the different treatments of photosynthetic rate, transpiration rate and stomatal conductance consistent with the trend, and with the reduction of the total amount of supplementary irrigation gradually decreased, and with the increased level of water deficit, the rate of reduction increased, and transpiration rate is faster than the degree of great extent reduced photosynthetic rate. Changes in leaf water using efficiency does not have a certain regularity, the treatment(T1N2) which jointing of high moisture and heading stage of moderate deficit was the highest, T1N1 treatment in jointing and heading stages with high moisture were minimum. With the advance of the growth process of corn processing, Fv / Fo and Fv / Fm increased at first while then decreased. Among different treatments, except T1N2, Fv / Fo and Fv / Fm decreased with the declining of total irrigation quantity, especially the treatment of severe water stress at heading stage decreased fastest.ΦPSⅡand ETR of different treatments aslo showed decreasing trends and over time, ETR increased its declining rate.The evaporation of summer corn showed a pulse-shaped curve in the whole growth period, after each irrigation or rainfall, the evaporation of summer corn has a same trend---an obviously upward trend, and then gradually decreased. In each growth stage,the variation of maize evaporation accounted of water consumption showed that the highest rate appears in seedling stage,and then gradually decreased. Days to heading- filling stage, then, due to plant senescence, plant transpiration reduction ratio between the two obviously increased. Among different treatments, the treatments of severe deficit increased rapidly after irrigation or rainfall, the rate of increase was significantly higher than the rest of their treatments.The yield of T1N2 with high moisture at jointing stage and moderate deficit at heading stage was the highest. Compared toT1N2, T3N1 deal cut 22.44%, T3N2 treatment cut 24.6%, and T3N3 deal cut up to 29.01%, the difference reached an obvious level. T1N2 has the highest water using efficiency, jointing and heading stages were high water treatment, while T1N1 was lowest.The other dealings decling gradually with the reduction of the total amount of supplementary irrigation. Water using efficiency of T1N2 was higher than T3N1, T3N2, T3N3 and T1N1 treatment, respectively the rate of 12.78%, 16.9%, 19.79% and 26.92%. But if compared with the flooding irrigation, which is popularly used in the agricultural production,it can produce a little more , but water using efficiency can be improved about 15%.Comprehensive results of this study, under the conditions of using spatial and temporal way of supplementary irrigation, we preliminarily studied out a high production, high efficiency and optimal irrigation technology for summer corn.That is the method of combining alternate furrow irrigation with full irrigation at jointing stage (80% of field capacity) and moderate deficit (65% of field capacity)of heading stage, which is conducive to the increase in maize production and the rational optimization of water distribution, thus improving water using efficiency. |
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