Work

Marker-Assisted Selection at VEQ2 Increases α-Tocopherol Content in Rice Grains Without Yield Penalty

Year: 2026

Type: article

Abstract: Vitamin E is an essential dietary nutrient, yet deficiency affects large populations, especially in ricedependent developing countries. To dissect the genetic basis of grain vitamin E content in rice, we performed a genomewide association study (GWAS) on a diverse panel of 533 rice accessions. A major locus, VEQ2, was identified on chromosome 2, where the CC genotype significantly increased αtocopherol content compared with the TT genotype. We developed a kompetitive allelespecific PCR (KASP) marker for VEQ2 and validated its effect in an F₂ population derived from Baikezaohe (TT) and AKITAKOMACHI (CC), confirming semidominant inheritance. Through markerassisted backcrossing, we introgressed VEQ2 into an elite indica background, generating nearisogenic lines. The CC introgression lines exhibited α-tocopherol and α-tocotrienol levels that were approximately 1.86- and 5.28-fold those of the control, respectively, accompanied by reduced β-tocopherol, whereas the TT lines displayed the opposite metabolic profile, with no significant penalties in agronomic traits. Analysis of 4,726 accessions revealed strong subspecies differentiation: TT was predominant in indica (84.2%), whereas CC was nearly fixed in japonica (99.5%). Collectively, these findings demonstrate that VEQ2 serves as a key genetic switch modulating the rice vitamin E metabolic profile and represents a promising target for biofortification of indica rice without compromising yield.

Source: Plants

DOI: 10.3390/plants15192951