Pure line selection of purple glutinous rice with high anthocyanin in grain from local rice population in Northern Thailand

Abstract

Local rice population is an important genetic resource for special grain qualities, especially purple glutinous local rice contains anthocyanin which has antioxidant properties beneficial to human health. However, local rice populations are genetically heterogeneous. Therefore, it is needed to characterize desirable trait for utilization of local rice population using pure line selection methods, the popular method for selecting local rice variety. The objectives of this study were to evaluate and select purple glutinous local rice from the highland of northern Thailand for high anthocyanin in grain. Six purple glutinous local rice lines have been selected for high grain anthocyanin concentration and were evaluated morphological and agronomical traits and determined anthocyanin concentration in brown rice. The experiment was carried out for two consecutive years under non-waterlogged condition during the rice growing season. In the first year, the experiment was conducted under pot condition while the following year was conducted under field experiment. The results of the first-year experiment showed that the morphological variation of all evaluated traits was not detected among the six selected lines. However, anthocyanin concentration varied among the six lines. Two high anthocyanin concentration lines were selected, PiEiZu 1 and PiEiZu 3, and were used as materials for the second-year experiment. The results of the second-year experiment showed that PiEiZu 1 contained the highest anthocyanin concentration in brown rice. The average anthocyanin concentration of PiEiZu 1 over two experimental years ranged from 28.4 – 37.5 mg/100g, two times higher than purple glutinous rice check varieties. In addition, PiEiZu 1 had high grain yield similar to upland rice check varieties, 656 kg/rai. This study suggested that PiEiZu 1 is the potential purple rice pure line with high anthocyanin concentration and yield recommended for special quality rice production and could be used as genetic resources for rice breeding program.