Adaptive capacity of winter wheat varieties and breeding material under the conditions of the South Steppe

Abstract

Purpose. To study the adaptive signs of varieties and breeding material of winter wheat developed at the Institute of Irrigated Agriculture of the National Academy of Sciences of Ukraine. Methods. Field, laboratory (determination of the water-holding capacity of leaves at major phenological stages), structural analysis, drought tolerance estimation (the method is based on the seed ability to germinate in sugar solution with high osmotic pressure), qua­lity analy sis, and statistical analysis. Results. Having a high-yiel­­ ding potential, modern varieties of winter wheat realize only 45–50% of their yield potential as their adaptability is still insufficient to ensure guaranteed stable yield. Therefore, to create highly adaptive varieties and to search me­ thods of evaluating breeding material in terms of adaptability remains a challenge for modern practical breeding. Among the studied in rainfed conditions winter wheat varieties of the Institute of Irrigated Agriculture which are adaptable in terms of plant height and yield, there is a genetically determined difference between drought-resistant genotypes, which makes it possible to select the best of them. These genotypes are 80–90 cm tall, they ensure a yield potential of 10.5 t/ha and the following quality indicators of grain: protein content 14%, sedimentation 55–75 ml, kernel hardness 95%, gluten content 32%, gluten quality I–II group Conclusions. The research on the drought and heat resistance of winter wheat carried out in the most important ontogenetic periods against two backgrounds – irrigated and rainfed – in conditions of climate change of the steppe zone served a basis for new breeding material and varie­ties. The Institute of Irrigated Agriculture’s varieties that have complex adaptive capacity have passed state variety examination and recognized as suitable for introduction in the farms in the South of Ukraine.