Phytosanitary status of barley crops in two types farming

Abstract

One of the major issues in the organic farming of cereals is the increase in weed, disease and pest infestation compared to conventional farming. The aim of this study was to compare the phytosanitary condition of the cultivars of barley grown in two types of farming systems – organic and conventional. This study was conducted in the period of 2013-2016 on medium strong, sandy-clay to light clay leached vertisols at the Institute of Agriculture in Karnobat, Bulgaria, on the certified field for organic farming and the experimental field for conventional farming. In the experiment were tested winter multi-row barley cultivars - Aheloy 2, Veslets, IZ Bory and Bozhin. Phytosanitary monitoring was carried out. In conventional farming of winter multi-row barley, no varietal difference. In organic farming, the varietal difference was well-expressed. The lowest level of weed infestation was observed with cultivar Veslets, and the highest – with the cultivar IZ Bory. In organic farming, for all the varieties of multi-row barley was reported the occurrence of Ustilago nuda, and the degree of infestation was under 10%. In conventional farming was observed higher degree of infestation of leaf diseases (Pyrenophora teres and Rhynchosporium secalis), than in organic. In conventional farming, higher density of aphids was reported for the cultivars IZ Bory and Bozhin. The lowest degree of infestation was reported for cultivar Veslets, followed by Aheloy. In organic farming, the tendency remains the same, and the degree of infestation over the years was much lower than in conventional farming.