Transient albino and revertible to green (TARGreen) rice mutant: simple, affordable and beneficial novel tag for rapid genetic purity testing in rice (Oryza sativa L.)

Abstract

A key problem that long remains challenging in rice ecosystem restoration is how to ensure quality seeds to re-establish rice varietal specific communities. Despite the available approaches such as use of seeds from authenticated sources, it is invariably argued that such seeds may harbour little genetic variability. In this study, a simple, affordable and alternative strategy is proposed: use of mutant line transient albino and revertible to green (TARGreen) derived from Oryza sativa var. ASD16. Rice line ASD16 is considered as a mega-variety in South India and it has shown rich harvest since its release in varying environments. However, the chief problem faced by the farmers is identification of genetically pure ASD16 plants in the field since it is often mixed with seeds from other rice-lines. To circumvent this problem, a chemical induced mutagenesis study was conducted in ASD16, which lead to the identification of TARGreen. After germination, TARGreen remains albino for 21 days and after that, they gradually turn into green leaves. Further studies on this line over several generations established that TARGreen trait was a Mendelian single recessive gene and the plants can able to produce the same quantity and quality of seeds as that of ASD16. Besides discussing immediate applications of TARGreen in seed industry, its proposed applications in hybrid seed production and identification of TARGreen specific markers for its efficient introgression into other rice mega-varieties is also outlined hereunder.