Characteristics of amphidiploids in the Triticum-Aegilops-Haynaldia-Agropyron group
Published in Scientific Papers. Series A. Agronomy, Vol. LV-2012
Written by Hristo STOYANOV
Amphidiploids in Triticum-Aegilops-Haynaldia-Agropyron group are an important part of the modern wheat breeding process, because of their valuable characteristics: resistance to biotic and abiotic stress factors. Sixteen amphidiploids and 25 synthetic wheat lines are observed for biotic and abiotic stress resistance. Observations (excluding germination of some amphidiploids seeds) are made under field conditions. In all amphidiploids and synthetic wheat lines no symptoms of powdery mildew (Erysiphe graminis DC.), leaf rust (Puccinia recondita Rob. et Desm.), septoria blotch (Septoria tritici Desm.) occur in tillering and adult plant phase. Synthetic wheats show low resistance to tan spot (Pyrenophora tritici-repentis (Died) Drechs.) in all phases of their development. The amphidiploids Chinese Spring x Haynaldia villosa, 45k (T. durum x Ae. speltoides), A1-6 (T. durum x T. boeoticum) and A3-8 (T. polonicum x T. boeoticum) possess very low frost tolerance (20-40%) as evaluated under field conditions. Lines developed from T. aestivum x Agropyron species crosses exhibit very good frost tolerance. Some of the observed lines (amphidiploid No.114, and (T. timopheevi x Ae. tauschii)), are not attacked by the cereal leaf beetle (Lema melanopa L.), probably because of the presence of well-developed trichomes on the leaves and stems. T. turanicum x T. timopheevi amphidiploid is determined with very fragile spikes and very low germination (12.5%). Low seed germination is registered in the T. durum x Agr. elongatum amphidiploid, too. In spite of some negative spike characteristics, the amphidiploids involved in this study, are important sources of genes which could be successfully utilized in wheat breeding.