Impact of the variety and severity of Cercospora beticola infection on the qualitative and quantitative parameters of sugar beet yields

Abstract

Cercospora leaf spot (CLS) causes significant economic losses. Cercospora beticola, the fungus that causes this disease, quickly acquires resistance to the active substances of the used fungicides. Therefore, the combination of chemical protection and varieties with increased resistance to CLS is currently the basic way to fight this disease. The aim of the study was to check the reaction of selected breeding materials and varieties of Kutnowska Hodowla Buraka Cukrowego (KHBC) in conditions of fungicides protection, without protection and artificial inoculation. In the years 2011–2013 field experiments were carried out in Straszków (Wielkopolskie voivodeship). The study used 2 varieties of sugar beet grown by KHBC: Finezja, Luzon and the breeding line KTA1015 with different levels of resistance to CLS. Three treatments were studied: control plots (no chemical control and no inoculation), inoculated plots and protected plots. The sugar beet crop was analyzed on yield, biological and technological sugar content and molasses-forming substances content in the pulp. The highest average yield of sugar beet of the studied varieties was obtained in the treatment with fungicide protection. The yield of the tested varieties grown on control plots and inoculated with mycelial fragments was lower by 4.6% and 11.3%, respectively. The lowest content of molasses-forming substances was found in the pulp of roots from chemically protected plots. The content of these compounds increased with the severity of CLS.