磷素营养对降香黄檀幼苗生长及叶片养分状况的影响  

Effects of Phosphorus Supply on Growth and Foliar Nutrition of Dalbergia odorifera Seedlings

作　　者：赵霞[1] 徐大平[1] 刘小金[1] 张宁南[1] 杨曾奖[1] 

机构地区：[1]中国林业科学研究院热带林业研究所,广州510520

出　　处：《植物研究》2018年第2期218-224,共7页Bulletin of Botanical Research

基　　金：中央级公益性科研院所基本科研业务专项资金(RITFYWZX201407)~~

摘　　要：设置0、15、30、60、100、150 mg P·株^(-1)等6个磷素处理开展降香黄檀幼苗盆栽试验,测定各处理幼苗的生长、生物量、叶片养分含量等指标,采用临界浓度法确定降香黄檀幼苗的适宜施磷量,从而探讨不同磷素水平对降香黄檀幼苗生长和叶片养分状况的影响,揭示其磷素需求规律以及适宜的磷供应范围。结果显示磷肥能促进幼苗生长和生物量的积累,而且随施磷量的增加,各指标呈现先升高后降低的趋势,最高值出现在60 mg P·株^(-1)处理,其苗高、地径、叶面积、生物量分别为对照的3.07、2.35、49.21和24.25倍。施磷显著降低幼苗叶片氮、钾含量,提高磷、镁含量,其中30、60、100 mg P·株^(-1)3个处理间叶片磷含量差异不显著,约为对照的1.65倍。根据幼苗生物量与叶片磷含量、氮钾含量比、磷钾含量比的抛物线关系,确定叶片最适磷含量范围为1.35~2.32 g·kg^(-1),由此推断降香黄檀幼苗最适宜的施磷量为60~100 mg P·株^(-1)。A pot trial was conducted for Dalbergia odorifera seedlings with fertilization at levels of 0, 15, 30, 60, 100 and 150 mg P per seedling in a completely randomized block design, and seedling growth performance, biomass and foliar nutrient contents were measured and analyzed. Suitable phosphorus application was finally determined for growing seedlings of this species by critical level approach. Growth and foliar nutrient of D. odorifera seedlings were studied under different levels phosphorus addition to reveal the phosphorus demand and determine the optimal phosphorus supply for its seedlings. The results showed that addition of phosphorus fertilizer could enhance growth and biomass accumulation of D. odorifera seedlings. With the increase of phosphorus supply, seedling height, root collar diameter, lead area and biomass increased first and then declined, and their peaking values occurred at the fertilizer level of 60 mg P per seedling, which were 3.07, 3.35, 49. 21 and 24.25 times of those of control. P fertilization decreased foliar nitrogen and potassium contents, while increased foliar phosphorus and magnesium contents, and foliar P contents showed no significant difference among fertilization treatments of 30, 60 and 100 mg P per seedling, which were about 1.65 times of that of control. Taking parabolic relationship between seedling biomass and foliar phosphorus content, content ratios of nitrogen to potassium and phosphorus to potassium, the optimal foliar phosphorus content ranged from 1.35 -2.32 g · kg^-1 , and 60 - 100 mg P per seedling was determined as the optimal phosphorus supply for D. odorifera seedlings by critical level approach.

关 键 词：磷素 降香黄檀 苗木生长 叶片养分 

分 类 号：S792.28[农业科学—林木遗传育种]