The effects of an innovative digestate and wood ash mixture fertilizer on potato yield quality

Abstract

Field trials with the potato variety ‘Rigonda’ were carried out in a sod stagnogley soil. Soil agrochemical parameters were: pHKCl 5.9, organic matter content – 2.3%, phosphorus (P2O5) content – 149 mg kg-1, and potassium (K2O) content – 200 mg kg-1. Potato plots were established using different treatments of a fertilizer mixture consisting of pig and cattle manure digestate and woodchip ash in different ratios (digestate to wood ash = 4:1 and 3:1). The doses of the innovative mixed fertilizer for potato were 15 and 30 t ha-1. Both norms of the digestate from pure pig and cattle manure were used as control options. The experimental design was an RCB with three replications. Crude protein content in potato dry matter varied from 8.28% to 10.94%. The application of fertilizer mixtures increased the dry matter content by 1.4–2.0%, reaching an average of 21%. Fertilizer treatments which produced higher tuber yields or higher starch contents gave also higher starch yields. In our studies, the average starch content in potato tubers dry matter was 73.3% and 15.3% in a fresh potato tuber, but the average starch yield reached 3.55 t ha-1. The objective of the research was to study the influence of the rates of the digestate and wood ash mixture fertilizer on the quality of potato yield.