Numerical Classification of Western Balkan Drought Tolerant Maize ( Zea mays L.) Landraces

Abstract

Global warming and predictions of climatic changes additionally put breeding for drought tolerance in the focus of breeding programm es for maize. Extensive studies on the existing gene bank collection of the Maize Rese arch Institute “Zemun Polje“ have been performed with the aim to identify and form in itial sources for the development of maize inbreds more tolerant to drought. All accessi ons (about 6,000) were exposed to controlled drought stress in Egypt. Out of this num ber, approximately 8% of the tested genotypes were selected. In this study attention wa s given to 321 selected Western Balkan maize landraces, adapted to temperate climate growi ng conditions and the day length. Data derived from morphological characterization ac cording to CIMMYT/IBPGR descriptors for maize, along with the application o f numerical classification methods, were used to define homogeneous landraces groups ba sed on morphological similarities. Results obtained from hierarchical and non-hierarch ical analyses revealed the formation of 11 divergent groups. According to the obtained g rain yield and visually scored stalk lodging and stay green, approximately 15% of the ac cessions from each of 11 groups were selected. Further investigations are towards defini ng their heterotic patterns and their possible utilization in developing and improving sy nthetic populations. Keywords : Correspondence analysis, Discriminant analysis, H omogenous groups.