COMPARISON OF LATE BLIGHT RESISTANCE AND YIELD OF POTATO VARIETIES

Growing more resistant potato varieties is one of the most effective strategies to control lateblight, to protect potato yield and to prevent harming the environment. the main aim of our studywas to identify potato varieties with higher resistance to late blight and which were high yielding inestonian conditions and suitable for organic farming. during the three-year trial, twelve potato varietieswere tested at the j?geva plant breeding institute (pbi) in 2010–2012. foliage late blight(phytophtora infestance (mont) de bary) and yield were estimated. first infection of late blight occurredin different times during the trial years. the three-year average infection level indicatedthat early varieties ‘arielle’, ‘impala’ and ‘princess’ were more damaged than other varieties in thefirst estimation. late varieties ‘ando’, ‘anti’, ‘juku’ and ‘sarme’ had higher late blight resistance.their foliage damage remained less than 30% in the last estimation. the new medium variety‘teele’ had a lower infection rate than other medium varieties and did not significantly differ fromlate varieties. based on these data, late varieties, early variety ‘maret’ and medium variety ‘teele’can be considered suitable for organic farming. the new variety ‘teele’ had the highest threeyearaverage tuber yield (52.8 t ha-1). varieties ‘impala’, ‘princess’ and ‘secura’ had significantlylower yield. yield loss of these varieties might have been caused by higher late blight infectionduring trial years.