Impact of a Fish Protein Based Organic Amendment On Microbial Community Structure, Membership, & Function.

Agriculture practices impacts many important properties of soil ecosystems such as soil pH, organic carbon, and bacterial community structure and function.  Organic farming has become an attractive alternative due to the increased public awareness of the negative environmental impacts that conventional farming has along with food safety. [1,2,3,4]  However, small organic farming’s impact on the environment specifically the soil bacterial habitat has not been studied. Soil bacterial communities are functionally critical as they provide the enzymes essential for nutrients recycling, plant growth, and matter decomposition.  [1, 2,3,4] The purpose of this study is to evaluate the impact of poultry litter, megabloom (fish protein), and convention (NPK) fertilizer on soil bacterial community structure and function.  The field study will use four varieties of sweetpotato: J66 (white flesh), NCC-58 (orange flesh), BH (purple flesh), and Watley Lauret (orange flesh) which will be grown for 120 days. Experiments were conducted as a randomized complete block design with four blocks and four treatments with three replications totaling 48 plants per replication.  Organic amendments and conventional fertilizer will be split and applied at the rate of 54.7305kilogram/acre ( kg/ac) based on soil tests one week after planting and at four weeks as single bands 15cm from the plant and covered. Bulk soil samples will be collected at 14 weeks and at harvest. Rhizosphere samples of sweetpotato plants will also be taken at harvest.  Soil parameters to be analyzed in this study soil are pH, enzymatic activity, organic carbon, total nitrogen content, bacterial community structure and membership. [5] Preliminary results showed lower DNA concentrations in the rhizosphere than expected results on based on literature. Additional results will be included as research progresses.