Research Of Fuji Apple Tree Transpiration And Fertilizer Coupled In Weibei Plateau

Because of the high altitude, abundant light and heat resources, the large temperature difference between day and night ,the Weibei loess plateau region becomes the most suitable area for apples. However, due to the lack of rational management of fertilization and irrigation and improper fertilizer and water input, fruit trees disorder in water and fertilizer, Fuji apple production in this area is low and unstable and the potential productivity of fruit trees cannot be brought into full play. Therefore, the technology of thermal diffusion determining stem flow is used in this paper to study the transpiration rules of apple trees ,moreover water and fertilizer coupling test is carried out. The results show as follows:(1) The changes of transpiration rate of apple trees present in single or double peak curve under the sunny weather conditions,while the multi-peak curve under the cloudy weather conditions; each month's average transpiration rate changes in the trend of single peak curve in addition to double peak curve in May, June and July. The quantity of transpiration in each day is different obviously, for the maxmum one is 3.59 mm/d in July while the minimum one 0.27 mm/d in January.Average transpiration rate of apple trees within one year is 1.79mm which changes in the single peak curve. From 8:00 to 20:00 transpiration is 1.65mm accounting for around 92 percent of the total transpiration.The total transpiration of apple trees shows a "S" type curve.(2) July, August in the transpiration of the largest, respectively, are 111.38 mm and 101.05 mm; January, December in the transpiration of the smallest, are 8.29 mm and 9.76 mm.Transpiration rate of apple trees under the condition of natural precipitation are similar to that under the condition of appropriate soil moisture content at the start-up time, the peak time and change curve in different months respectively. Under the condition of appropriate soil moisture content, the maximum transpiration and the minimum are 111.38mm(Jul.) and 8.29mm (Jua.)respectively. Under the condition of appropriate soil moisture content , annual transpiration is 652.63mm compared with that under the conditions of natural precipitation which is 526.98 mm ,decreasing by 125.65 mm.(3) For the year of 2007, the rainfall it is very difficult to meet the water consumption of the potential transpiration. In the growing season of August through October, precipitation meet the needs of transpiration basically. But in April, May, June and July, water supply and consumption is contrary conspicuously. It is very essential that strengthen water supply.(4) Space change of transpiration rate indicates that the transpiration of apple trees in the southeast and southwest are similitude. For the smaller north transpiration, stem in southeast and southwest are appropriate to install the TDP.(5)In order to explore water and fertilizer management in the Weibei loess Plateau orchard, a water and fertilizer coupling test has been made in five different levels using five factors of water, organic fertilizers, nitrogen, phosphate and potash fertilizer, including three repeats .It's founded: The order of the influence of the main factor on the size of apple trees yield is: potash > phosphate > nitrogen > water> organic manure, which illustrates that phosphorus and potassium fertilizer have the largest influence on the yield. Followed by nitrogen fertilizer, and how water and organic fertilizer work on the yield is not very clear; all factors have interaction effect with potash fertilizer, among which phosphate fertilizer is best, followed by nitrogen fertilizer, organic fertilizer and water;From the viewpoint of yiled,the optimal irrigation is 470-827kg for one tree ,and the optimal fertilizer is that organic fertilizers for one tree is 89-154kg, nitrogen fertilizer 1.3-1.84kg, phosphorus fertilizer 2.41-2.93kg,and potassium fertilizer2.16-2.75kg.