| In the process of fruit tree growth, as an important nutritional elements, nitrogen has important influence on the growth and development of fruit tree, fruit yield and quality。Studying different nitrogen levels on the growth of apple seedlings and the growth characteristics of different varieties apples could provide theoretical guidance for the efficient use of fertilizer in fruit tree production. The material used in this experiment was one-year-old grafted seedlings(Fuji/Malus hupehensis Rehd, Honeycrisp/Malus hupehensis Rehd and Qinguan/Malus hupehensis Rehd), compared with no fertilizer treatment, the experiment was set four different fertilizer treatments,respectively3 g, 6g, 9g, 12g(fertilization is divided into three times, fertilization amount for each time was 1g, 2g, 3g, 4g), the biomass, plant height, stem diameter, chlorophyll content, photosynthetic rate and plant nitrogen of the varieties were measured. The experimental results showed that, different nitrogen levels had significant influence on the growth and development of Fuji, Honeycrisp and Qinguan seedlings. In the scope 0g—9g of the total nitrogen content on the Fuji seedlings, the total nitrogen content of plant leaves, the growth index and photosynthetic index increased first and then decreased with the increasing of the amount of nitrogen; Honeycrisp seedlings growed best under the 6g of nitrogen levels; the total nitrogen content of plant leaves, the growth index and photosynthetic index of Qinguan seedlings increased with the increasing of the amount of nitrogen. The experiment shows that one-year-old potted Fuji growed best under the 9g of the nitrogen levels, Honeycrisp was 6g, while the optimum nitrogen level of Qinguan seedlings was needed further research. |
