Gene effects involved in the manifestation of growth characteristics and resistance to thermal stress [Articol]

Abstract

Data are presented on the response of tomato plant growth characters in hybrid combinations F1, F2, BC1, BC2 and parental forms to stress temperatures (40, 42, 10°C). The reaction of seedlings to high temperatures (40, 42°C) and low positive (10oC) was differentiated depending on the combination, character and temperature level. The calculation of the degree of dominance (hp) of the growth characters (radicle, stem, whole seedling) of tomatoes demonstrated the significant influence of positive (+), negative (-) dominance factors on their phenotype. By researching the genetic effects involved in the phenotype and the inheritance of the radicle and stem length character, it was found that for each combination, in the control (25oC) and thermal stress (40oC, 42o and 10oC) variants, effects with positive values (increasing) and, with negative values (which decrease) the character. The combinations under study showed duplicated epistasis, which reveals the need for long individual selections in order to obtain tomato genotypes resistant to high temperatures.