Effects Of Rapidly Available Water Content On The Physiological-biochemical Characteristics And Nutrient Utilization Of Plants

For the purposes of studying the effects of different soil water content on the plants physiological-biochemical characteristic and nutrient use efficiency of plants, three raw materials were taken as the raw materials of the culture media to simulate the different soil water content. Seedling pot experiment and soil-less culture were conducted, and two winter wheat varieties and two tomato varieties were selected to for property analysis. The main physiological-biochemical indexes include water content, water saturation deficiency, dry matter weight, malondialdehyde (MDA) content, reducing sugar content, Hydrogen peroxide content. The induced protein under water stress and phosphate stress were isolated and the molecular weights of induced proteins were calculated. The paper presents the theory foundation for water-saving agriculture and the high-efficiency of the nutrient in the arid region. The major results as follows:1. For the purpose of studying the relationship between the raw materials composing and the physical properties, sand, sawdust and vermiculite were taken as raw materials to compose the media. The results show that the sand content has a inverse correlation with the water content, total hole pace, capillary porosity, water intake rate and capillary height, and has a p ositive correlation with percolation rate. The sawdust content has a positive correlation with the water content, total hole pace, capillary porosity andpercolation rate, has a inverse correlation with the water intake rate. The vermiculite content has a positive correlation with the water content, total hole pace, capillary porosity, water intake rate and the capillary height, and has a inverse correlation with the percolation rate. When the sand: sawdust: vermiculite i s 2:0:8, the available w ater content i s 9 6.14%. When the sand: sawdust: vermiculite is 8:2:0, the available water content is 4.95%.2. Less the available water content, less water content of the plants. The water saturation deficiency is increasing with the increasing water content. And there have significance difference between the water content of the plants under different water contents.3. With the decrease of the available water content, the MDA content and the reducing sugar content are increasing, but the E^C^ content is decreasing. The MDA content and the reducing sugar content is the highest when the available water content is 8.82%, and it has a significant difference with that of the others.4. Under different available water content condition, the total nutrient contents of the plants variety with the different N content (P content or K content) in the media. Under same available water content, within certain range, the accumulation of the N (P or K) is increasing with the increased fertilizer content. But when the fertilizer put in the media is out of the range, the fertilizer content had a inverse effect on the nutrient accumulation in the plants. Under different available water content, applying fertilizer can promote the nutrient uptake of the plant, and there have significant different between the treatments of applying fertilizer and those having no fertilizer. The nutrient accumulations of two winter wheat varieties are higher than that of two tomato4varieties.5. In order to research the induced protein under water stress and P stress, the winter wheat (9401) were choose as the material to conduct the test. After 3 days, the induced proteins were isolated. Under p-deficiency condition, a new band of protein can be found, and its molecular weight is 38018.9Da. Under normal condition, there's no induced protein. When the water potential is -0.40MPa, three new bands were found under P deficiency condition, and the molecular weight is 38018.9Da, 45708.8Daand 33270.8Da; two new bands were found under P supply condition, and the molecular weight is 45708.8Da and 33270.8Da. When the water potential is -0.86MPa, two new bands were found under P deficiency c ondition, and the molecular weight is 38018.9Da and 33270.8Da; three new bands wer...