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Effects of Water and Fertilizer Spatial Coupling on Growth and Use of Water and Nutrition of Winter Wheat

Author: LiKaiFeng
Tutor: ZhangFuCang
School: Northwest University of Science and Technology
Course: Agricultural Soil and Water Engineering
Keywords: Water and fertilizer coupling Winter Growth, Physiological Index Water use efficiency Yield and Composition Nitrogen and phosphorus distribution
CLC: S512.11
Type: Master's thesis
Year: 2009
Downloads: 64
Quote: 1
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Abstract

Water and nutrients are the basic conditions for crop growth, is the impact of agriculture, sustainable development, particularly in dryland agriculture a major factor. Water and nutrients from the relationship between the look, water and nutrients and are a pair of coupling factor, there is a greater interaction between water and fertilizer. Past people on fertilizer and yield relationship between a lot of research has made important progress. But the study focused on the amount and timing of water and fertilizer coupling terms, while the coupling of space research data is relatively small. In this study, Shaanxi Province status of water resources in agriculture, irrigation and existing way through the soil column test tube planted to winter wheat crop for the instructions to the soil dry pad Orthrosols (Loess soil) as tested soil samples, using spacer tube planted soil column experiment, simulated soil moisture, nutrient spatial distribution of several conditions, different soil moist root zone research methods (whole wet-on-wet down dry, dry on the wet) and fertilization (overall fertilization, fertilization top , the lower fertilization) interaction on winter wheat growth and development, photosynthesis, root activity, allocation and utilization of nutrients, water use efficiency and yield and composition effects. Through research, obtain the following main conclusions: (1) the overall wet on wet and dry handling lower compared to dry on the wet treatment significantly reduced flowering - filling stage of winter wheat plant height; from a different way of looking at fertilization, the lower fertilization treatment to reduce before the jointing stage height and leaf area, but in flowering - filling stage, different fertilization treatment differences between the small and the fertilization process of leaf area during that period reached the maximum. Fertilizer Coupling different treatments on winter wheat biomass and organ allocation impact varies, on the lower trunk wet treatment significantly increased the shoot dry weight and total biomass, but root dry weight and root to shoot ratio above the maximum dry the wet processing; Upper fertilization and overall fertilization treatments shoot dry weight, root dry weight and total biomass than the lower fertilization treatment, and shoot ratio did not differ. (2) photosynthetic rate and stomatal conductance was a significant positive correlation between photosynthetic rate is based on maintaining high water loss for the price. Between photosynthetic rate and grain yield also significantly positively correlated, particularly in the photosynthetic rate after flowering the greatest impact on yield, the correlation between the two reached P lt; 0.01 significant level, the higher photosynthetic rate is the basis of crop yield . Dry the wet processing on different levels of reduced winter wheat yield and harvest index, but water use efficiency is much higher than; Upper fertilization in grain yield and water use efficiency were higher than the lower fertilization treatments; different fertilizer coupling process, mainly through affect single grain number to influence production. (3) flowering - filling stage, the overall root fresh weight of wet treatment were lower than the previous wet-dry and dry on the wet treatment increased 5.63% and 18.09%. Wet on wet with the whole process under dry root activity was not significant, but both were significantly higher than under dry wet processing; fertilization from a different point of view, at tillering and jointing stage, the upper fertilization and overall root fertilization treatments fresh weight, dry weight and root vigor than the lower fertilization treatments. But in flowering - filling stage, the lower fertilization root activity fell less than the other two fertilization. (4) of winter wheat in different parts of nitrogen and phosphorus contents were as follows: before maturity, stem gt; roots; maturity, grain gt; stem gt; roots. Stems and roots of nitrogen and phosphorus with the growth process forward, was gradually decreasing trend. Dry the wet processing on different levels of reduced tillering and jointing stage of shoot and root nitrogen and phosphorus content, but in Yanghwa - filling period is higher than the other two wet manner, mature stems and leaves of different ways moist and root nitrogen and phosphorus content of mixed. The lower leaves and stems and roots fertilization of nitrogen and phosphorus in different growth stages were lower overall fertilization treatment is more conducive to maintaining high shoot and root nitrogen and phosphorus content. (5) different fertilizer coupling effects on the distribution of ammonium smaller and different growth stages of ammonium nitrogen content of the soil is insignificant; but different fertilization on nitrate and phosphorus distribution in soil significant effects of soil nitrate and phosphorus content of the soil with fertilizer are closely related. (6) From the point of view throughout the growing period, the upper fertilization treatment plant height, leaf area, photosynthesis, root activity and biomass and grain yield were significantly higher than the lower fertilization treatment, and the overall fertilizer treatments had no significant difference. But reducing nitrate fertilization upper and lower phosphorus in the soil residues, thereby facilitating Xiacha crop root uptake and contamination of groundwater due to leaching. From the point of view of actual production in calcareous soil fertilizer nitrogen to nitrate-based end products, and easy to move, and phosphate in the soil is not easy to migrate this feature, regardless of the overall wet or dry down on the most common Wet soil moisture distribution, with phosphorus fertilizer when still applied into the 0-35cm soil is better.

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