Influence of the temperature stress on growth and development characters of the tomato genotypes [Articol]

Abstract

The paper presents the results of screening of some varieties and 2 reciprocal F2 tomato hybrid combinations: Desteptarea x Flacara/Flacara x Desteptarea and Flacara x Vrojainii/Vrojainii x Flacara, based on resistance to low positive temperatures (10°, 11°C) in early ontogenesis. Seedlings grown at 25ºC served as a control. The analysis of the variability of the resistance character was performed based on germination, length of the embryonic radicle, stem and intact seedling. In the most cases, low temperatures produced significant inhibition of the both germination and growth organs. By cluster analysis (k-means method) in the 11°C variant, the varieties Chihlimbar, Desteptarea, Flacara, Mary Gratefully and the reciprocal combination F2 Desteptarea x Flacara/ F2 Flacara x Desteptarea were identified, which formed a separate cluster, with the highest values of the evaluated characters. In the case of temperature 10°C – the genotypes/populations Flacara, Mary Gratefully, F2 Desteptarea x Flacara, F2 Flacara x Desteptarea, F2 Flacara x Vrojainii presented the cluster with the highest germination values. Research of the influence of low positive temperatures on the distribution of tomato Solanum lycopersicum plants into phenotypic classes based on radicle length, demonstrated that the profile of the F2 reciprocal populations was influenced by both the temperature level and the parental entity when obtaining F1 reciprocal hybrids