The influence of low-temperature on the photochemical activity of chloroplasts and activity of antioxidant enzymes in maize leaves

Abstract

The effects of low growth temperature on the activities of photosystems (PS) 1 and 2 and antioxidant enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) and catalase (CAT) in leaves of various maize inbred and hybrid genotypes (parental lines, F1 hybrids, F2 and backcross generations) were investigated. Considerable decrease of the PS 2 activity (contrary to the activity of PS 1) due to low-temperature stress was observed in the majority of genotypes/generations examined. The GR, APX and SOD activities markedly increased due to chilling, whereas the activity of CAT showed lesser changes which depended on the genotype/generation analysed. The higher susceptibility of the inbred line 2013 to low temperature was transmitted to further generations in case this line was used as the maternal parent. The intraspecific variability in photosynthetic and antioxidant parameters was caused particularly by the dominance (negative or positive), however, the level of the expression of this effect often changed after low-temperature stress and was probably the cause of the increase in the positive F1 heterosis observed in this case. Other genetic effects (e.g. the additivity, and particularly the additive or dominant maternal effects) were also found to contribute to the intraspecific variability in parameters analyzed. The dominant maternal effects possibly played an important role in maintaining positive heterosis in F2 generation.

The effects of brassinosteroids on photosynthetic parameters in leaves of two field-grown maize inbred lines and their F1 hybrid

“…1), confirming again the previous findings that F1 hybrids of maize show positive heterosis not only for yield and morphology parameters, but for various photosynthetic parameters as well (e.g. Baer and Schrader 1985, Mehta et al 1992, Holá et al 1999, Ahmadzadeh et al 2004, Kočová et al 2009). The inbred line CE704 was characterized by the lowest content of Chls and Cars and usually also by the lowest PS 1 activity and HRA (Fig.…”

The evaluation of photosynthetic parameters in maize inbred lines subjected to water deficiency: Can these parameters be used for the prediction of performance of hybrid progeny?

“…All statistical evaluations were made with the CoStat computer programme, version 6.204 (CoHort Software, Monterey, CA, the U.S.A.). The quantitative genetic analysis aimed at the establishment of the relative importance of the additive and the non-additive (dominance, maternal) genetic effects was based on the modified model of Eberhart and Gardner (1966) as described in Kočová et al (2009). The computer programme CBE3 from the Software Package CBE, version 4.0, was used for this analysis (Wolf 1996).…”

Characteristics of chlorophyll fluorescence and antioxidative system in super-hybrid rice and its parental cultivars under chilling stress

“…Higher contents of defense enzymes were found to be correlated with higher chilling tolerance of cucumber radicles (Kang and Saltveit 2002). While photosynthetic characteristics and the role of ROS scavenging enzymes under abiotic stress in many other crops have been well documented (Bertamini et al 2006, Kočová et al 2009), very few data are yet available on relationships of hybrid rice and its parental cultivars. In the present study, the chill tolerance of super-rice hybrid, LYPJ, and its parental cultivars were characterized.…”