黄连木容器苗生长对缓释肥的响应

【目的】 揭示黄连木(Pistacia chinensis Bunge)容器苗生长、根系发育和养分状况对缓释肥的响应规律,筛选最佳施肥量。【方法】 设置3个包膜缓释肥(美国奥绿肥5号)施肥量(0.4、0.8、1.6 g/株)和1个空白对照(未施肥),生长季末测定4个处理下苗木形态指标、养分状况和根系发育情况。用方差分析、多重比较等方法,探明苗木生长对不同施肥量的响应差异,同时将地径、苗高、根生物量、茎生物量、全株生物量分别与施肥量建立数学模型,预测最佳施肥量。【结果】 苗木地径、苗高、全株生物量、根总长、根表面积、根体积和氮、磷、钾含量随着缓释肥施肥量的提高而显著增大,其中施肥量为1.6 g/株时达到最大,苗高、地径和全株生物量分别为24.0 cm、4.9 mm和3.9 g/株。根茎比则随施肥量的提高而减少,对照最大为2.8。地径、苗高、根生物量、茎生物量和全株生物量与施肥量构建的数学模型R²均大于0.95。【结论】 低施肥量下养分主要用于根系的生长,随着施肥量增加,大部分养分开始往地上部分转移,促进茎和叶的生长。地下部分的第1径级(03.0 mm)根随着施肥量增加显著增加。综合5个数学模型预测结果,认为黄连木容器苗缓释肥最佳施肥量在1.28～1.95 g/株之间。

The growth response of Pistacia chinensis Bunge containerized seedlings to slow-release fertilizer

Abstract: 【Objective】The aim of this study was to elucidate the growth pattern, root development and nutrient status of Pistacia chinensis Bunge containerized seedlings in response to slow-release fertilizer to determine the optimal fertilizer amount. 【Method】Three application levels of film-coated and slow-release fertilizer(0.4, 0.8 and 1.6 g/seedling)by Osmocote USA, and a blank control(CK)were used as treatments. The morphological attributes, nutrient status, and root development of the treated seedlings were measured at the end of the growing season. The data was tested by means of variance analysis and multiple comparisons. Mathematical models between the fertilizer amount and the root-collar diameter(RCD), seedling height, root biomass, stem biomass and total plant biomass were established to predict the optimal fertilization amount.【Result】 The RCD, seedling height, total plant biomass, root length, root surface area, root volume, and the contents of nitrogen, phosphorus and potassium increased with increasing fertilizer amount. When the amount of applied slow-release fertilizer was 1.6 g per plant, the seedling height, RCD and total plant biomass showed the maximum levels of 24.0 cm, 4.9 mm and 3.9 g/seedling, respectively. The ratio of root to stem decreased with increasing fertilizer amount, with the highest value of 2.8 observed in the control treatment. The mathematical model coefficient was higher than 0.95.【Conclusion】 Nutrients are mainly used for root growth when fertilizer concentration is low. However, most nutrients begin to translocate to the stem with increasing amount of available fertilizer, promoting the growth of stems and leaves. The first(03.0 mm)grades of root diameter increased significantly with increasing fertilizer amount. The results of the five mathematical models indicated that the optimal amount of the slow-release fertilizer for P. chinensis containerized seedlings varied between 1.28 and 1.95 g per seedling.