Evaluation of morphological and kernel micronutrient traits in maize landraces

Abstract

Maize grains contain high level of carotenoids and tocopherols compared with other cereals. Among carotenoids the β-carotene has the highest activity and is considered important in breeding programs of biofortified crops. Changes in carotenoids content in the maize grain could be influence of genotype x environment interaction, or effect of existing relationship between the color of the endosperm and the presence of carotenoids. This research was performed to estimate differences in morphological traits, grain content of tocopherols (α-, β+γ-, δ-), β-carotene, lutein and zeaxantin in local and introduced populations from Maize Research Institute 'Zemun Polje' gene bank. Micronutrient content was detected by using high-performance liquid chromatography (HPLC). Coefficient of variation for morphological traits was less than 10%, except for grain yield per plant which vary about 18,6%. α-tocopherol content was in the range from 1.04-8.42 μgg-1 DW, and β-carotene content varied from 0.26 to 7.95 μgg-1 DW. δ-tocopherol was in significant correlation with number of kernels per row (r=0.700***), and β+γ-tocopherol was in significant negative correlation with plant and ear height (r=-0.601***; r=-0.591**). Correlations between morphological traits and α-tocopherol were weak and without significance. Kernel color was significantly correlated with the content of zeaxantin (r=0,590***) and β-carotene (r=0,398*). For biofortification purposes a pool of 11 landraces with increased content of both, β-carotene and α-tocopherol, will be created based on obtained results.

U odnosu na druge žitarice, zrno kukuruza sadrži visok nivo karotenoida i tokoferola. Od svih karotenoida β-karoten ima najveću aktivnost i smatra se najznačajnim u biofortifikacijskim programima oplemenjivanja žitarica. Ovo istraživanje je imalo za cilj da utvrdi razlike u morfološkim svojstvima, sadržaju tokoferola (α-, β+γ-, δ-), β-karotena, luteina i zeaksantina kod lokalnih i introdukovanih populacija kukuruza iz banke gena Instituta za kukuruz 'ZemunPolje'. Sadržaj mikronutrienata je utvrđen primenom HPLC metode. Koeficijent varijacije za morfološka svojstva je bio manji od 10%, osim za prinos zrna po biljci (Cv=18,6%). Sadržaj α-tokoferola je bio u rasponu od 1,04-8,42 μg g-1 suve mase, a β-karotena od 0,26 to 7,95 μg g-1suve mase. δ-tokoferol je bio u značajnoj korelaciji sa brojem zrna u redu (r=0,700***), dok je β+γ-tokoferol bio u značajnoj negativnoj korelaciji sa visinom biljke i klipa(r=-0,601***; r=- 0,591**). Korelacije između morfoloških svojstava i α-tokoferola bile su slabe i nesignifikantne. Boja zrna je bila u značajnoj korelaciji sa sadržajem zeaksantina (r=0,590***) i β-karotena (r=0,398*). Za potrebe biofortifikacije 'pool' od 11 populacija sa povećanim sadržajem i β-karotena i α-tokoferola biće formiran na osnovu dobijenih rezultata.