SCREENING FOR DROUGHT RESISTANCE IN SPRING SOFT WHEAT FROM VARIOUS GEOGRAPHICAL ORIGINS BY SEED GERMINATION IN SUCROSE SOLUTIONS WITH DIFFERENT OSMOTIC PRESSURE AND ASSESSMENT OF THEIR ADAPTABILITY TO THE ACUTELY DRY CONDITIONS OF WESTERN KAZAKHSTAN

Abstract

This article reports the results of laboratory studies on the germination of seeds of varieties and samples of spring soft wheat of various geographical origins in sucrose solutions with different osmotic pressure. We used 175 samples and varieties of spring soft wheat from the collection of the All-Russian Institute of Plant Genetic Resources named after N.I. Vavilov (St. Petersburg, Russia) and selection from the Aktobe Agricultural Experimental Station. Seeds of 112 varieties and samples were germinated in sucrose solutions at both 16 atm and 18 atm and were characterized for drought resistance. There were 6 “weakly resistant” varieties, where the proportion of sprouted seeds ranged from 20 to 38%; 3 “medium-resistant” varieties – where 50 to 59% of seeds sprouted; 15 samples with above-average resistance – where the proportion of germinated seeds ranged from 60 to 80% and 88 “highly resistant” samples where 81 to 100% of seeds sprouted in sucrose. Data from laboratory experiments are also confirmed by field observations and assessments from 2017 to 2019. 2019 was characterized by severe combined drought. During this period, the varieties allocated to the “highly resistant” group were characterized by a short growing season, long ear length and high values for the number of grains, number of spikelets, weight of 1000 grains and yield (in g/m2). The listed “highly resistant” varieties can be recommended as promising sources of adaptability and drought resistance for the purposes of breeding spring soft wheat in Western Kazakhstan.