Cold resistance of modern soya cultivars while germinating seeds under the conditions of low positive temperatures

Abstract

The aim and tasksof the study foresaw the estimation of modern soya cultivars from plant breeding institutions of Ukraine on cold resistance during the period of seeds germination and singling out the resistant genotypes to low temperatures at the stage of germination for including them in plant breeding programs as the initial material and creation of adaptive cultivars to cold.Material and methods.The research was carried out during 2014–2016 years in the laboratory of plant immunity to diseases and pests at the Institute of plant growing named after V.Ya.Yuriev of NAAS. The material for the research was represented by 34 soya cultivars from plant breeding institutions of Ukraine. Cold resistance was determined by the quality of germinated seeds underlow positive temperatures (+10 ºC ) and the percent was calculated from the quantity of tested germinated seeds in the optimum conditions for the crop (+24 ºC).Results and discussion.Soya cultivars involved in test were grown in the research rotation of the plant growing Institute named after V.Ya.Yuriev of NAAS. The weather conditions during the period of soya vegetation by years of study were characterized as optimum in 2014 and 2016 years(HTC=1.14 and 1.32) and arid in 2015 year(HTC=0,6).The results of seeds germination of all soya cultivars in laboratory under the temperature of +10 ºC showed differences between cultivars as to their cold resistance. That allowed to divide them into groups. The group of weak cold resistant cultivars (21–40 %) includes 6 plant breeding elaborations – Pyssanka, Farvater, Russa, Vil’shanka, Sharm, Vezha. The group of cultivars with average cold resistance(41–60 %) comprises 14 cultivars (Bajka, Sprytna, Kobza, Victoryna, Rajduga, Perlyna, Vyshyvanka, Denni, Gali, Rapssodia, Khvylya, Diademma, Khutoryanochka, Knyazhna and Romashka). The group of cultivars with cold resistance higher than average(61–80 %) includes 7 cultivars: Estafeta, Mal’vina, Symphonia, Suzirja, Triada, Zolushka, Mel’pomena. The group of high cold resistant cultivars is represented by 6 cultivars: Podyaka, Krassunya, Siverka, Syajvo, Zlata, Fejeriya.Conclusions.According to the resultsof studying 34 cultivars created in the leading plant breeding institutions 3 cultivars were singled out during 3 years (Melpomena, Podyaka, Syajvo). Among them there are one with higher than average cold resistance (Mel’ponela, 76,6 %) and two with high (Podyaka and Syajvo,89,7 and 91,9 accordingly). Cultivars Zlata, Siverka and Fejeriya are characterized by high level of cold resistance and high crop productivity. Zlata cultivar with the level of cold resistance 87,7% gave the crop productivity higher than conventional standard by 116,6%, Siverka – by 117,7%(the level of cold resistance is 82,6%), the crop productivity of cultivar Fejeriya was higher from conventional standard by 104,9% (the level of cold resistance is 82,7%). The represented cultivars with high and average cold resistance are valuable initial material for soya plant breeding for given trait and are suitable for early terms of sowing