不同调控措施对基质根区养分累积及番茄生长的影响

发布时间：2018-06-26 21:39

本文选题：开放式 + 封闭式　；参考：《中国农业大学》2017年博士论文

【摘要】：农业环境污染程度的加重和资源性废弃物产生量的增加使得农业环境的治理和资源性废弃物的无害化资源化处理成为我国农业发展的重要课题,发展基质栽培既可保护农业环境又能消纳部分资源性废弃物,是实现以上课题的重要途径。但基质栽培中营养液管理不当时栽培根区会出现养分累积,进而引发栽培周期缩短、养分缺失、产量和品质低下等问题。营养液的管理受营养液供液方式、基质类型和营养液配方等因素的影响。为此,本文系统分析了长季节栽培中开放式和封闭式供液方式下基质栽培根区养分累积强度和特征的差异性,并探究了岩棉、椰糠和草炭蛭石三种基质在栽培过程中各自根区养分含量和组成的变化情况,系统揭示了基质特性对根区养分离子累积强度和特征的影响;最后以惰性基质岩棉为载体从营养液配方调整角度出发研究了开放式供液方式下C1-替代部分NO3-以及不同K/Mg和Ca水平在缓解栽培系统中养分累积的应用效果,主要结论如下:(1)封闭式和开放式供液方式下番茄根区均存在养分累积和离子比例失衡现象。封闭式和开放式供液方式下根区溶液EC值随生育期的延长不断增加,且封闭式的增幅要高于开放式,最高EC值分别为17.2 mS cm-1和11.9 mS cm-1。各养分离子对EC值的贡献率为NO3-K+Ca2+Mg2+SO42-H2PO4-。开放式和封闭式供液方式根区离子比例失衡特征、失衡程度相当,均表现为K+、Ca2+和H2PO4-比例降低,Mg2+、NO3-和SO42-比例上升。高EC值和离子比例失衡会导致番茄产量降低与果实脐腐病患病率增加。与开放式供液方式相比,封闭式供液方式能实现番茄基质栽培的节水节肥和环境友好型发展。(2)基质类型会影响根区溶液EC值和pH值的变化,椰糠和草炭蛭石根区溶液EC值和pH值均高于岩棉处理。采收后期岩棉、椰糠和草炭蛭石处理根区溶液EC分别为12.3 mScm-1、17.2 mS cm-和16.6 mS cm-1;与定植初期相比,采收后期岩棉、椰糠和草炭蛭石处理根区溶液pH值分别下降了 1.4、1.3和0.7个单位。基质类型不同,渗透胁迫程度不同,椰糠和草炭蛭石栽培能有效减缓高EC值对果实脐腐病和产量的影响。(3)基质类型会影响根区养分离子的组成。椰糠栽培会增加根区溶液K+含量;草炭蛭石栽培会降低根区溶液K+和H2PO4-含量,增加Ca2+含量。(4)不同供液方式和不同基质栽培条件下根区溶液EC值均呈阶段性的变化。开放式供液方式下在番茄果实膨大期-采收初期根区溶液EC值增幅最大,封闭式供液方式下和不同基质栽培条件下在番茄采收中期根区溶液EC值增幅最大。(5)营养液中用Cl-替代部分NO3-可提高NO3-利用效率,减少NO3-的排出。高Cl-氐NO3-处理一年内向外界环境中排出的N03-比常规营养液处理减少了 0.6 thm-2。提高营养液中Cl-含量可促进番茄对Ca的吸收。(6)与K/Mg为6.5相比,提高营养液K/Mg水平(13.0)能有效缓解基质栽培中K耗竭和Mg累积问题。提高Ca供应水平能有效提高番茄Ca含量。与常规Ca处理相比,高Ca处理番茄老叶、新叶和果实中Ca含量分别提高了 4.1%、36.3%和8.1%。
[Abstract]:The aggravation of agricultural environmental pollution and the increase of the production of resource waste make the treatment of the agricultural environment and the disposal of the harmless resources of the resource waste become an important issue in the development of agriculture in our country. The development of the matrix cultivation can not only protect the agricultural environment but also eliminate some of the resource waste. It is an important way to realize the above problems. But the nutrient solution management in the substrate culture is not at that time the nutrient accumulation in the cultivated root zone, which leads to the shortage of the cultivation cycle, the lack of nutrient, the low yield and the low quality. The management of nutrient solution is influenced by the factors such as the way of nutrient solution, the type of matrix and the formula of the nutrient solution. The changes in nutrient content and composition of three substrates in rock wool, coconut bran and peat vermiculite were investigated in the cultivation process. The effects of matrix characteristics on the accumulation of nutrient ions and characteristics of nutrient ions in root region were revealed. Sexual substrate rock wool was used as the carrier to study the application effect of C1- substitution part NO3- and different K/Mg and Ca levels on nutrient accumulation in the cultivation system from the angle of nutrient solution formulation. The main conclusions are as follows: (1) there is nutrient accumulation and ion ratio in the root region of Tomato under closed and open solution. The EC value of the root zone solution increased with the prolongation of the growth period under closed and open mode. The increase of the closed type was higher than that of the open type. The highest EC value was 17.2 mS cm-1 and 11.9 mS cm-1. respectively. The contribution rate of each nutrient ion to the EC value was NO3-K+Ca2+Mg2+ SO42-H2PO4-. open and closed mode root zone ions. The proportion of imbalance is the same as K+, the proportion of Ca2+ and H2PO4- decreased, the proportion of Mg2+, NO3- and SO42- increased. The high EC value and the imbalance of the ion ratio would lead to the decrease of Tomato Yield and the increase of the incidence of fruit navel rot. (2) the matrix type will affect the change of EC value and pH value of root zone solution. The EC value and pH value of the solution of coconut bran and hirudite root zone are higher than that of rock wool. The EC of the late harvest rock wool, coconut bran and the peat vermiculite root zone solution EC are 12.3 mScm-1,17.2 mS cm- and 16.6 mS cm-1 respectively. Compared with the early harvest, the rock wool and coconut were collected at the early stage of harvest. The pH value of the root zone solution of chaff and peat vermiculite treatment decreased by 1.4,1.3 and 0.7 units respectively. The matrix types were different, the degree of osmotic stress was different. The cultivation of coconut bran and peat vermiculite could effectively slow down the effect of high EC on the fruit navel and yield. (3) the matrix type would affect the composition of nutrient ions in the root region. The cultivation of coconut bran increased the root solution K+ The content of vermiculite could reduce the content of K+ and H2PO4- in root solution and increase the content of Ca2+. (4) the EC value of root solution in different ways of feeding and culture of different substrates all showed a phase change. The maximum increase of EC value in the root zone solution at the early stage of the expansion of tomato fruit under the open feeding method was under the closed feeding mode and the difference. The EC value of root zone solution in the medium period of tomato harvest was the biggest increase. (5) replacing part NO3- with Cl- in nutrient solution could increase NO3- utilization efficiency and reduce NO3- discharge. High Cl- di NO3- reduced N03- in one year to outside environment and reduced Cl- content in nutrient solution to increase Cl- content in nutrient solution. Ca absorption of Ca. (6) compared with K/Mg 6.5, improving the K/Mg level of nutrient solution (13) can effectively alleviate the problem of K exhaustion and Mg accumulation in substrate cultivation. Improving Ca supply level can effectively improve the content of Ca in tomato. Compared with conventional Ca treatment, high Ca treated tomato old leaves, Ca content in new leaves and fruits are increased by 4.1%, 36.3% and 8.1%., respectively.
【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S641.2

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