Influence of humic acids, irrigation and fertilization on potato yielding in organic production

M. Kołodziejczyk

University of Agriculture in Krakow, Faculty of Agriculture and Economics, Department of Agroecology and Crop Production, Mickiewicza street 21, PL31–120 Krakow, Poland
Correspondence: m.kolodziejczyk@ur.krakow.pl

Abstract:

The study aimed at determining the impact of organic fertilization, humic acids and irrigation on potato yielding in organic production system. Fertilization variants included: Humac Agro; manure; vermicompost; Fertil Bioilsa C-N 40-12.5; manure + Humac Agro; vermicompost + Humac Agro; Fertil Bioilsa C-N 40-12.5 + Humac Agro. Irrigation was carried out using drip lines. The highest tuber yield was determined on treatments fertilized with vermicompost. The combined application of organic fertilizers and humic acids resulted in increased total yield between 6 and 9%, whereas commercial yield from 5 to 10%. Application of fertilization resulted in increased total yield of tubers in individual fertilizer variants from 1.9 to 10.8 t ha^-1, and commercial yield from 1.6 to 12.3 t ha^-1. Water-use efficiency remained in the range from 35.2 to 113.1 kg mm^-1, whereas irrigation water-use efficiency from 9.9 to 166.3 kg mm^-1. Humic acids used in the study enhanced fertilizer and water-use efficiency.

Key words:

Effect of different production systems on yield and quality of potato

V. Eremeev, I. Keres, B. Tein, P. Lääniste, A. Selge and A. Luik

Institute of Agricultural and Environmental Science, Estonian University of Life Sciences,Kreutzwaldi St. 1, EE51014 Tartu, Estonia; e-mail: Viacheslav.Eremeev@emu.ee

Abstract:

In the experimental field of the Department of Field Crops and Grassland Husbandry the late maturing potato variety „Ants‟ was grown in the following variants: conversion to organic, N0P0K0, N50P25K95, N100P25K95 and N150P25K95. Pesticides were used in mineral fertilizer variants. In N0P0K0 and mineral fertilizers variants insecticide Fastac 50 was used. The total yield of tubers as well as the proportion of marketable tubers increased significantly with the use of mineral fertilizers (N50P25K95, N100P25K95 and N150P25K95). Tubers from conversion to organic and N0P0K0 variants had significantly higher starch content, compared to the variants where mineral fertilizers were used, but the overall yield of starch remained lower. Increasing the amount of nitrogen fertilizer is positively correlated with the nitrate content in the tubers. The number of tubers infected by potato brown rot and potato soft rot did not differ significantly, but there were fewer tubers infected with black scurf in conversion to the organic variant.

Key words:

black scurf, brown rot, marketable yield, soft rot, Solanum tuberosum, starch content.