EVALUATION SYSTEM AND INHERITANCE OF EXPR ESSIVITY OF RESPONSE TO TEMPERATURE AND LIGHT IN BARLEY (HORDEUM-VULGARE L) - RESPONSE TO SHORT-DAY AND TEMPERATURE

The expression of response to short day was studied in barley (Hordeum vulgare L.) cultivars grown under artificial climate conditions. The response phenotypically expressed during two ontogeny periods: formati on of generative sphere (FGS) and maturity of reproductive organs (MRO ). The effect of high cultivation temperature (HTC) on the expressivit y of plant response to short day (SD) and its inheritance was also stu died. It was shown that gene Ssd 5 determined plant sensitivity to SD during both FGS and MRO. Gene Ssd 6 controlled sensitivity and Ssd 7, insensitivity to SD only during MRO, When compared to moderate cultiva tion temperatures (18/12 degrees C), high temperature (24/16 degrees C ) decreased the expressivity of response to SD in five cultivars, incr eased it in 15 cultivars, and did not change it in 26 cultivars, inclu ding 12 cultivars with a neutral response to SD. In the cross Prima Be larusi x k-28041, HTC changed the state of genes (dominant-recessive) controlling the expressivity of plant response to SD.