Characterization of two strains of bacteria for phosphate solubilisation from hog manure solids and for plant growth promotion

来自养猪场的粪便可以是农业作物的有益土壤改良剂，因为它含有高含量的氮和磷。大多数磷酸盐是不溶性的，由于施用制度是基于氮含量，随着时间的推移，这种不溶性磷酸盐的大部分积累在土壤中。这限制了每年可以施于土壤的猪粪量。在马尼托巴省，养猪场附近的一些田地已经达到了允许添加的磷酸盐的极限，而且将粪便运输到任何远距离都变得成本高昂，限制了其在更广泛地区的应用。使用固体的酸发酵，然后在磷酸盐溶解细菌（PSB）的存在下进行有氧消化，应该导致磷酸盐从粪肥固体中溶解和分离。KGS希望调查从这种处理中产生两种土壤肥力增强产品的可行性：1）高可溶性磷酸盐茶，其可直接作为土壤肥料施用或作为鸟粪石再沉淀以有效运输，和2）发酵固体，富含PSB的土壤可以作为土壤调理剂和有益细菌的来源，用于原位磷酸盐溶解和动员到植物根部，大田作物几种PSB还具有植物促进特性，超出磷酸盐增溶。为KGS集团工程分离的两种细菌菌株可能有效地溶解磷酸钙，并可能在促进植物生长方面具有一定的功效。目前Engage提案的目的有3个方面：1）使用不同的碳源和不同的培养基组成表征不同不溶性形式的磷酸盐矿物（磷酸钙、鸟粪石）的生长和溶解。2)注释和比较2种菌株的基因组，以便对观察到的生长特征提供合理的理解，并进一步了解这些菌株可开发的遗传潜力。3)为了比较植物相关磷酸盐溶解的植物促进能力以及使用马尼托巴省相关作物（油菜、大豆、玉米等）的生长促进能力，并确定这些菌株在根际的竞争力。

Manure from hog farming can be a beneficial soil amendment for agricultural crops, since it is high in both nitrogen and phosphate. Most of the phosphate is insoluble, and since the application regime is based on nitrogen content, much of this insoluble phosphate accumulates in soil over time. This limits the yearly amount of hog manure that can be applied to the soil. In Manitoba, some of the fields near hog farms have reached the limit of allowable added phosphate, and transport of manure any great distance becomes cost prohibitive limiting its application to a wider region. Use of an acid fermentation of the solids, followed by an aerobic digestion in the presence of phosphate solubilizing bacteria (PSB) should lead to the solubilization and separation of the phosphate from the manure solids. KGS wants to investigate the feasibility of generating two soil fertility enhancing products from this treatment: 1) a high soluble phosphate tea which can be applied directly as a soil fertilizer or re-precipitated as struvite for effective transportation, and 2) the fermented solids, enriched with PSB can act as a soil conditioner and a source of beneficial bacteria for in situ phosphate solubilization and mobilization to the roots of field crops. Several PSB also have plant promotion properties, beyond phosphate solubilization. Two strains of bacteria isolated for KGS Group Engineering may be effective at solubilizing calcium phosphate and may have some efficacy in promoting plant growth. The purpose of the current Engage proposal is 3 fold: 1) To characterize the growth and solubilization from different insoluble forms of phosphate minerals (calcium phosphate, struvite) using different carbon sources and different medium composition. 2) To annotate and compare the genomes of the 2 strains in order to provide a rational understanding for the growth characteristics observed and provide further insights into the genetic potential of these strains that could be exploited. 3) To compare the plant promotion capabilities for plant associated phosphate solubilization as well as growth promotion capabilities using Manitoba-relevant crops (canola, soybean, corn, etc.), and determine the competitiveness of these strain in the rhizosphere.