Abstract
The combination of the trend of Japanese food consumption with the health benefits of black rice is in high demand for rice consumers in Thailand. For this challenge, incorporation of desirable traits from temperate japonica white rice, Akitakomachi and tropical indica black rice, Riceberry was performed by pedigree selection with maker assisted selection (MAS) and these desirable traits have been presented in breeding progenies. The three candidate lines showed highly favorable agronomic characteristics and a high grain yield, with short grains and good cooking quality, similar to japonica rice, in a tropical climate. In addition, these lines showed black coloration of the pericarp, indicating high nutritional value (including Fe, Zn, Vit B6, Vit E and folate levels) and phytochemical, antioxidant and antidiabetic activities, similar to those of the Riceberry parent. In terms of the sensory testing of unpolished rice, two breeding lines (69-1-1 and 72-4-3) showed higher scores than their parents. However, only 69-1-1 was identified as japonica type according to its genetic background. Therefore, this breeding program, involving the crossing of a temperate japonica white rice with a tropical indica black rice, can create novel black short grain rice variety adapted to a tropical environment, similar to japonica-type rice.
Evaluation of japonica rice (Oryza sativa L.) varieties and their improvement in terms of stability, yield and cooking quality by pure-line selection in Thailand