Evaluation of cold resistance and early ripening traits in sterile forms of tomatoes

Abstract

The aim of the study was to identify a valuable source material among available tomato sterile forms for tomato breeding for cold resistance. Materials and methods. The article presents the results of a study of 14 tomato sterile forms for adaptive ability based on a complex trait of cold resistance, the elements of which were determined in field and laboratory conditions. The material was assessed according to a set of features: the increase in plant height, the rate of growth recovery, the duration of the sowing-seedling and seedling-fruit ripening periods. Calculations of the parameters of general adaptive ability, homeostatic and variance of specific adaptive ability of sterile form genotypes by earliness and cold resistancehave been performed. Results. The level of general and specific adaptive ability, as well as homeostatic of cold resistance, were determined. Valuable source material has been isolated according to the characteristics of cold resistancein the field and laboratory conditions. The forms Mar ps 59, Mar ps 53 and Sat ps 52 were characterized by highest cold resistance in the laboratory conditions. These lines were characterized by seed germination in the range of 0,3–2,8 %, compared with other sterile forms with the germination 0,1–0,2 %. The increase in plant height under cool conditions in mentionedforms (Mar ps 59, Mar ps 53 and Sat ps 52) was higher (45–54 %) compared with other sterile forms. In the field, the duration of the interphase period «sowing – seedlings» was the shortest in the forms Mar ps 59 and Sat ps 52 compared with other forms studied. Thus, the duration of the period «sowing–germination» in the mentioned forms was 19 and 18 days respectively, against the standard Flora 20 days. The increase in seedling height was 60–80 %, to the same extent with other forms and the standard 74 %.