New Rainfed-Drought Rice Variety developed through In Vitro Mutagenesis

Abstract

In vitro mutagenesis (IVM), a technique combining tissue culture and gamma irradiation (30 Gy ⁶⁰Co), was performed with a modern upland rice variety NSIC 2001 Rc 9 (NSIC Rc9), locally known as Apo. The breeding strategy was implemented to improve the variety’s grain quality, specifically its grain size and shape, and amylose content. The induced mutation strategy regenerated 55 IVM1 families from which the IVM2 population was generated comprising of 206 segregating plants. Phenotypic variability assessment conducted in 2009 wet season resulted in the selection of 150 plants with acceptable phenotypes. After a series of evaluations and selection for grain quality, drought stress tolerance and grain yield, seven elite lines were selected for multi-environment trial (MET) in four rainfed locations. The MET identified four lines ready for nomination to the National Cooperative Testing (NCT) for further evaluation and recommendation to the National Seed Industry Council (NSIC) as a new variety for release. In 2015, the line PR41395-NSICRc9-IVM2009DS 50-1-4 (IVM-032) was entered into NCT as one of the breeding lines evaluated under the rainfed-drought prone rice ecosystem. In 2019, the line was released as a new variety recommended for cultivation and consumption. The IVM-032 was officially registered as NSIC 2019 Rc572 and with the variety name of Sahod Ulan 28.