不同供氮模式下福建柏1年生容器苗生长响应机理研究

发布时间：2019-06-03 12:20

【摘要】：福建柏(Fokienia hodgnsii)我国二级保护珍稀树种,是一种用途广、经济价值高的南方造林树种。施肥是提高福建柏幼苗苗木质量的核心,以福建柏1年生容器苗为研究对象,在温室条件下,采取指数供氮和平均供氮两种模式,系统分析两种供氮模式5个不同供氮水平处理下幼苗苗高、地径、生物量、根系形态、叶绿素含量、可溶性蛋白含量以及硝酸还原酶活性的变化规律,旨在为福建柏1年生容器苗合理供氮提供参考依据。主要研究结果如下:1.不同供氮模式对福建柏1年生容器苗在生长季(7-10月)的苗高、地径、生物量产生显著影响。氮素处理水平在0～750 mg范围内,随着供氮素水平的提高,苗高、地径、生物量表现出先增加后减小的变化趋势。氮素供应水平为600 mg.株-1时,苗高、地径生长量取得最大值,平均供氮模式为11.69 cm、1.14 mm,指数供氮模式为13.58 cm、1.38 mm。指数供氮模式E4处理幼苗根、茎、叶以及总生物量高于其他处理,分别为1.17 g、1.39 g、2.51 g、5.07 g,其中总生物量和根系生物量是ck的1.75、1.57倍。氮素供应水平达到750 mg.株-1时,苗高、地径及生物量的增加减弱。同一氮素浓度供应,指数供氮模式优于平均供氮模式。2.氮素的施入影响福建柏幼苗根、茎、叶生物量的分配格局,根系生物量比例在20.32%～23.14%之间,地上生物量(茎、叶生物量)比例在77.27%～79.85%之间,明显高于根系生物量。指数供氮模式更有利于福建柏幼苗根、茎生物量比例的增加,其中根系生物量所占比例分别为 20.96%、22.40%、22.87%、23.14%、22.26%;E4、E3处理茎生物量所占比例最高,比ck分别提高了 2.96、2.54个百分点。3.应用根系扫描仪扫描及WinRHIZO根系分析系统对福建柏1年生容器苗根系形态指标进行测定,结果表明适量浓度的施氮有利于根系形态相关指标的提高。指数供氮模式E4处理下得到根系形态相关指标最大值,根长、根表面积、根体积、根平均直径分别为1083.43 cm、196.92 cm2、3.37 cm3、0.80 cm,比 ck 提高了 124.63%、87.31%、74.61%、37.93%。4.幼苗生物量指标与根系形态指标存在密切关系。幼苗总生物量与总根长、总根表面积、总根体积、根系平均直径之间相关系数分别为0.937、0.865、0.671、0.688,呈极显著正相关。根冠比与地上生物量、总根体积、根系平均直径相关系数分别为-0.159、-0.091、-0.039,呈负相关。比根长与根冠比相关系数为-0.508,呈极显著负相关。总生物量、地上生物量与根系生物量之间呈极显著正相关。5.幼苗根系生物量与苗高、地径之间存在密切关系,采用逐步回归、多元线性回归、多元非线性回归(洛伦兹模型、抛物面模型)四种拟合方法对幼苗根系生物量及苗高、地径进行拟合。以地上部分来预测地下根系生物量变化,抛物面模型具有更高的R2(0.92～0.978)和更小的RSS(0.234～0.841),拟合效果更精确。6.随着供氮水平的提高,叶绿素含量、可溶性蛋白含量、硝酸还原酶活性表现出先增后减的变化规律。氮素供应水平为600 mg·株-1时,叶绿素含量、可溶性蛋白含量、硝酸还原酶活性达到最高。该浓度氮素供应下,指数供氮模式E4处理叶绿素含量为4.26 mg·g-1、可溶性蛋白含量为3.78 mg·g-1、硝酸还原酶活性为4.83μg·g-1·h-1,比ck分别提高47.40%、30.34%、42.48%,比平均供氮模式A4处理分别提高9.51%、8.93%、3.43%,因此,指数供氮模式对幼苗相关生理指标的影响更显著。7.不同供氮模式对福建柏1年生容器苗苗高、地径及相关生理指标影响显著。在此基础上对其进行相关分析,结果表明,苗高、地径、叶绿素含量、硝酸还原酶活性间呈极显著正相关;可溶性蛋白含量与苗高、地径间相关系数为0.041、0.029,相关关系较弱。因此,不同供氮模式下,幼苗苗高、地径生长与叶片叶绿素含量、硝酸还原酶活性关系更加密切。
[Abstract]:Fokienia hoodgnsii is a rare species of rare tree species in China. It is a kind of southern forest tree species with wide application and high economic value. In order to increase the seedling quality of the seedlings of the Arborvitae, the seedling of the 1-year-old one-year-old was taken as the research object. Under the condition of the greenhouse, the index was used to supply the nitrogen and the average nitrogen for two modes, and the seedling height, the ground diameter and the biomass of the seedlings under the five different nitrogen supply levels were analyzed. The changes of the root morphology, the content of chlorophyll, the content of soluble protein and the activity of the nitrate reductase were used to provide a reference for the rational supply of nitrogen for the 1-year-old container of the Selaginella. The main results are as follows:1. The seedling height, ground diameter and biomass of the 1-year-old one-year-old one-year-old container in the growth season (7-10 months) were significantly affected by different nitrogen supply modes. The level of nitrogen treatment is in the range of 0-750 mg, and with the increase of nitrogen level, the seedling height, the ground diameter and the biomass show the change tendency of the first increase. The nitrogen supply level was 600 mg. When the strain was 1, the height of the seedling and the growth of the ground diameter were the maximum, the average nitrogen supply mode was 11.69 cm, 1.14 mm, and the index for nitrogen supply was 13.58cm and 1.38mm. The total biomass and root biomass were 1.17 g, 1.39 g, 2.51 g and 5.07 g, respectively, and the total biomass and root biomass were 1.75 and 1.57 times of ck, respectively. The nitrogen supply level reached 750 mg. When the plant-1, the seedling height, the ground diameter and the increase of the biomass decreased. In that same nitrogen concentration, the index of nitrogen supply is better than the average nitrogen supply mode. The distribution pattern of root, stem and leaf biomass was affected by the application of nitrogen, the biomass ratio of root system was 20.32% ~ 23.14%, and the proportion of aboveground biomass (stem and leaf biomass) was 77.27% ~ 79.85%, which was obviously higher than that of root system. The ratio of biomass of root system was 20.96%, 22.40%, 22.87%, 23.14% and 22.26%, respectively. The root morphology of the 1-year-old container was determined by the scanning of the root scanner and the analysis system of the WinRIZO root system. The results showed that the application of the appropriate concentration of nitrogen was beneficial to the improvement of the related index of the root system. The root length, root surface area, root volume and root mean diameter were 1083.43 cm, 196.92 cm2, 3.37 cm3, 0.80 cm, 124.63%, 87.31%, 74.61%, 37.93%, respectively. The seedling biomass index is closely related to the root morphology index. The correlation coefficient between total biomass and total root length, total root surface area, total root volume and root mean diameter was 0.937, 0.865, 0.671 and 0.688, respectively. The correlation coefficient between the root-to-crown ratio and the aboveground biomass, total root volume and root mean diameter was-0.159,-0.091,-0.039, and negative correlation. The correlation coefficient between the root length and the root crown was-0.508, and a negative correlation was found. The total biomass, aboveground biomass and root biomass were positively correlated. The biomass of the root system and the height of the seedling and the ground diameter of the seedling were fitted by stepwise regression, multiple linear regression, multiple nonlinear regression (Lorenz model and parabolic model). The ground part is used to predict the biomass of the underground root system, the parabolic model has higher R2 (0.92-0.978) and smaller RSS (0.234-0.841), and the fitting effect is more accurate. With the increase of nitrogen supply, the content of chlorophyll, the content of soluble protein and the activity of nitrate reductase show the change law of the first increase. The content of chlorophyll, soluble protein and nitrate reductase were the highest when the supply of nitrogen was 600 mg 路 plant-1. The content of soluble protein was 4.26 mg 路 g-1, the content of soluble protein was 3.78 mg 路 g-1, the activity of nitrate reductase was 4.83. m 8.93%, 3.43%, therefore, the effect of the index for nitrogen mode on the related physiological indexes of the seedlings was more significant. The effects of different nitrogen supply modes on the height, ground diameter and related physiological indexes of the 1-year-old Chinese-year-old container were significant. The results showed that the content of soluble protein was positively correlated with the content of chlorophyll and nitrate reductase, and the correlation coefficient between soluble protein and seedling height and ground diameter was 0.041, 0.029, and the correlation was weak. Therefore, under different nitrogen supply modes, the seedling height, the growth of the ground diameter and the chlorophyll content of the leaves and the activity of the nitrate reductase are more closely related.
【学位授予单位】：福建农林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S791.43

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