Reactions of anthocyanin rich in maize genotypes to low temperature treatments according to photosynthesis, gas exchange properties, and bio-active compounds

Abstract

Low temperatures during the early growing stages limit the productivity of maize considerably. Investigating responses of different coloured corns (Zea mays L.) to chilling may reveal alternative genotypes which can be preferred under early sowing conditions of water-shortage farming areas. The aim of this study is determining whether the color factor affects the tolerance to chilling in maize and which properties are effective on the low temperature tolerance. We exposed corns with different colours (white, yellow, red, purple) to different temperatures [8°C, 12°C, 16°C, 25°C (control)] and analysed the effects of temperature on morphological, physiological, bio-active properties and stress indicators. Using 14-day old seedlings, we noted that purple corn had the highest seedling length, seedling weight, chlorophyll content, stomatal conductance, chlorophyll B and total phenolic content in the 8°C and followed by white (photosynthesis rate, chlorophyll fluorescence, chlorophyll A and carotenoids), yellow (transpiration rate, sub stomatal CO2, and total antioxidant activity) and red corns (water use efficiency, total anthocyanin content and proline). On the other hand, white corn maintained its superiority in other treatments, receiving the highest values in 9 of 17 characteristics at 12°C, in 8 of 17 at 16°C and in 10 of 17 in the control. Performance of purple corn in the 8°C was the most remarkable one in all genotypes and treatments. Based on our results, it has been concluded that white and purple corns are more chilling tolerant genotypes and may be alternative for early sowing conditions in drought farming areas.