Screening stable potential rice mutants for grain zinc and iron accumulation and yield performance

Biofortification of rice through gamma radiation-induce mutagenesis in rice is a well-established approach to achieve sustainable development goals (SDG) 2, SDG 3 and SDG 12. Hence, this approach is considered as effective for both improving the yield and nutritional value of rice.In this regard, a field study was carried out for screening of stable rice mutants for their potential to accumulate high Zn concentrations and performed better yield.To obtain 40 stable rice mutants, 06 rice genotypes (Shua-92, Shadab, NIA-Mehran, IR-8, Sarshar and Shandar) were exposed to gamma rays doses of 100, 150, 200 and 250.The irradiated seeds were sown under the field conditions to obtain potential mutants.The soil used in the study was heavy in texture, calcareous and alkaline in nature, deficient in organic matter and DTPA extractable Zn.The experiment was laid out following RCBD with three replications, and each plot measuring of 8.0 m 2 (4m × 2m).Results revealed that grain yield varied from 3.58±0.11to 9.75±0.13kg plot -1 , Zn concentration 12±0.13 to 38±0.05 mg kg -1 while Fe concentration ranged from 3.0±0.11to 71±0.16 mg kg -1 .Phytic acid (PA) varied from 8±0.12 to 15±0.21 mg g -1 .Moreover, findings of the AMMI biplot revealed that grain yield and phytic acid exhibited higher interaction, whereas Zn showed relatively stable.Keeping in view the goal of biofortification in rice, best mutants based on multi-trait selection were M24 (Shua-200-4) which was very consistent across traits, M30 (Shadab-200-1-1) was stable and in good micronutrients, M35 (IR8-200-1) with strong Fe and stable, M10 (Shandar-200-4) had good Zn and yield stability and M22 (Shua-100-8) with yield stability and acceptable micronutrients.These findings suggest that both stable and specifically adapted mutants should be considered for breeding programs depending on target environments and nutritional traits.