ЭЛЕМЕНТЫ СТРУКТУРЫ УРОЖАЯ СОРТОВ ЯРОВОГО ЯЧМЕНЯ И ИХ ВКЛАД В ФОРМИРОВАНИЕ ВЫСОКОЙ ПРОДУКТИВНОСТИ РАСТЕНИЙ

The focus of the review is on the results of diagnostics of spring barley tolerance to drought using a direct vegetation experiment (“zasushnik”). It has been analyzed which elements of the yield structure are primary in the formation of high productivity of the crop under the insufficient water supply. The data about plant height of spring barley under the conditions of drought, optimal moisture and a field trial have been given. The plant height was 55-75 cmunder optimal moisture (control), it was 40-64 cmunder the conditions of a severe drought and it was 50-65 cmin a field trial (natural growing conditions), that is 5-10 cmlower than growing under optimal moisture (control). One of the responses of spring barley to water stress is reduce of a number of productive stalks per meter. The spring barley varieties ‘Leon’ (359 and 392 p/m 2 ) and ‘Shchedriy’ (369 и 400 p/m 2 ) showed the largest thickness of productive plant density under the conditions of experimental drought and a field trial. Different decrease of grain productivity and elements of yield structure (amount of seeds in a main ear, mass of 1000 seeds, mass of a main ear) of spring barley samples under drought have been defined. The review considers a gradient of reduce of ear dry biomass depending on different growing conditions as one of the criteria of assessment of drought tolerance. A minimum reduce of ear dry biomass after the effect of a stress factor (soil drought) was seen in the varieties ‘Leon’ (51%) and ‘Shchedriy’(51%). The analysis of correlation between these data and the amount of productivity has been carried out.