Morpho-Physiological Characterization in Eight Varieties of Maize (Zea mays L.) under Soil Salinity

Considering Iran and Azerbaijan to be origin countries in the Astara region, and in order to study the effects of salt stress on morphological and physiological characteristics, changes to eight maize cultivars were experimented on in three replications on the basis of randomized complete block design over three years. Cultivars included K3615/1, S.C704, B73, S.C302, Waxy, K3546/6, K3653/2, and Zaqatala-68, and they were cultivated in two pieces of land in Astara: one with normal soil and the other with salty soil. During the experiment, Na+ accumulation in leaves, chlorophyll a, chlorophyll b, leaf relative water content (LRWC), proline content, biomass per plant, harvest index, and grain yield per hectare were measured. Results from the experiment showed that, between locations (normal and saline) in most traits, significant differences were seen. And between varieties in all traits, significant differences were seen. The interaction between years and varieties for all traits was not significant. Comparison traits in different salinities showed that in most traits there are significant differences between genotypes. Proline content increased with increasing soil salinity. With increasing salinity, Na+ accumulation in leaves severely increased and the biggest accumulation was observed in S.C704. Maximum LRWC in B73 was measured in normal conditions. The highest amount of chlorophyll a, in normal conditions, was observed in S.C704 with 1.873 mg/g fresh weight of leaves, which was not significantly different from B73. Between chlorophyll a and chlorophyll b, Na+ and LRWC positive correlations were observed in non-stress conditions. Between chlorophyll a and chlorophyll b, yield per plant, and yield grain, significant positive correlations were observed in salty conditions.