山西晋中市石灰性土壤无机磷细菌的分离鉴定研究

发布时间：2018-03-11 12:12

本文选题：无机磷细菌　切入点：分离　出处：《西北师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：探究山西晋中市石灰性土壤中作物根际解磷细菌的种类、解磷能力以及解磷机制,根据研究结果以期筛选出高效稳定的解磷菌株,为了生产具有土壤解磷活性强的生物磷肥提供良好菌株,进而在石灰性土壤上实现以解磷细菌替代磷肥、降低磷肥用量、提高作物产量、降低环境污染的目的。石灰性土壤是其剖面中含有碳酸钙或碳酸氢钙等石灰性物质的土壤的总称。在我国多分布于北部和西北部半湿润、半干旱和干旱地区,其成土母质多为黄土状沉积物和石灰岩风化物。碳酸钙在剖面中的分布,根据不同的成土条件,有的与土壤均匀混合,有的沿土壤孔隙以菌丝或皮膜状的白色析出物存在,有的形成硬结核,还有的在一定深度形成碳酸盐积聚层。因此,石灰性土壤对磷有强烈的固定作用,因而土壤溶液中的磷浓度很低,且移动性很小。磷的移动性与土壤含水量有密切关系。而石灰性土壤处于降水较少的干旱及半干旱区,磷向根表的扩散和根系的生长都因土壤含水量偏低而削弱。缺磷是我国大面积石灰性土壤多种植物生长的限制因子。土壤缺磷已成为这些地区作物生长的主要限制因素。仅靠传统的改土施肥方法往往不能有效地解决土壤缺磷问题。本文从石灰性土壤无机磷细菌的分离,筛选入手。对山西晋中八个县区的农田、蔬菜大棚等地进行土样采集,对采集的土样进行细菌分离、筛选和鉴定,并通过查阅相关资料,对其中的细菌,酵母菌和霉菌等菌类做了详细的了解,筛选出六株长势较好和比较纯的无机磷细菌四株有机磷细菌。然后对菌株进行了无机磷和有机磷溶解能力测定,染色和形态观察,生理生化鉴定。根据形态观察和生理生化反应以及细菌鉴定手册,初步鉴定出两株属于假单胞菌属,四株属于芽孢杆菌属。对无机磷细菌溶解磷能力的研究发现:六株无机磷细菌中磷酸钙的溶磷能力W5是六株中最大的,W12是最小的,溶磷能力在86.34~190.86mg/l之间;而对磷矿粉的溶磷能力差距不大,最大的是W12,最小的是W15,溶磷能力在3.75~20.79mg/l之间。六株无机磷细菌对有机磷也有一定的解磷能力,相差不大,远不如对磷酸钙的溶磷能力强。对蛋黄卵磷脂的解磷能力在5.79~28.97mg/l之间;对大豆卵磷脂的解磷能力在0.80~24.32mg/l之间。通过分离鉴定石灰性土壤中的无机磷细菌,筛选出解磷效果较好的菌株,以期为改变土壤缺磷状态,充分利用土壤中微生物磷提供理论和依据。
[Abstract]:The species, ability and mechanism of phosphorus releasing bacteria in the rhizosphere of crops in calcareous soils of Jinzhong City, Shanxi Province were investigated. In order to provide a good strain for producing biophosphorus fertilizer with strong activity of soil phosphorolytic activity, phosphorus bacteria can be used to replace phosphate fertilizer in calcareous soil, the amount of phosphate fertilizer can be reduced, and crop yield will be increased. The purpose of reducing environmental pollution. Calcareous soil is a general term for soils containing calcareous substances such as calcium carbonate or calcium bicarbonate in its profile. The parent material of the soil is mostly loess sediment and limestone weathering material. The distribution of calcium carbonate in the profile, according to different soil forming conditions, is mixed evenly with the soil, and some exist along the soil pore as hyphae or white precipitates. Some form hard nodules, others form carbonate accumulations at a certain depth. Therefore, calcareous soils have a strong fixation on phosphorus, resulting in very low phosphorus concentrations in soil solutions. The mobility of phosphorus is closely related to soil water content, while calcareous soil is in arid and semi-arid areas with less precipitation. Phosphorus deficiency is the limiting factor for the growth of many plants in calcareous soils in China. Phosphorus deficiency has become the main limit of crop growth in these areas. In this paper, the problem of phosphorus deficiency in soil can not be effectively solved by traditional fertilization methods. This paper studies the separation of inorganic phosphorus bacteria from calcareous soil. Starting with screening. Soil samples were collected from farmland, vegetable shed and other places in eight counties in Jinzhong, Shanxi. Bacteria were isolated, screened and identified from the collected soil samples, and the bacteria among them were obtained by consulting relevant data. Four organophosphorus bacteria with better growth and purity were screened out, and the solubility of inorganic phosphorus and organophosphorus were measured, stained and observed. Physiological and biochemical identification. According to morphological observation, physiological and biochemical reactions and the manual of bacterial identification, two strains of Pseudomonas were preliminarily identified. Four strains belong to the genus Bacillus. It was found that the phosphate dissolution ability of calcium phosphate in the six inorganic phosphorus bacteria W5 was the smallest and the phosphorus solubilizing ability was between 86.34 and 190.86 mg / l in the six strains of inorganic phosphorus bacteria. However, the difference of phosphorus solubilization ability to phosphate rock powder is not big, the biggest is W12, the smallest is W15, and the ability of phosphorus solubilization is between 3.75 and 20.79 mg / l. The six inorganic phosphorus bacteria also have a certain ability to dissolve phosphorus on organic phosphorus, and the difference is not significant. The ability to dissolve phosphorus in egg yolk lecithin was between 5.79 and 28.97 mg / l, and for soybean lecithin was between 0.80 and 24.32 mg / l. The inorganic phosphorus bacteria in calcareous soil were isolated and identified. In order to change the status of phosphorus deficiency in soil and make full use of microbial phosphorus in soil, the strains with better phosphorus release effect were screened out in order to provide the theory and basis.
【学位授予单位】：西北师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S154.3

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