biostudies-literatureAlcock TDSlovenian Research AgencyRenewable Industrial Products from RapeseedRural and Environment Science and Analytical Services DivisionCrop Improvement Research ClubDelivering Low-Cost, High-Throughput Root Phenotyping Screens for Arable CropsBiotechnology and Biological Sciences Research CouncilScottish Government1616-1631https://www.ebi.ac.uk/biostudies/studies/S-EPMC8260142biostudies-literatureUnknown186(3)Magnesium (Mg) and calcium (Ca) are essential mineral nutrients poorly supplied in many human food systems. In grazing livestock, Mg and Ca deficiencies are costly welfare issues. Here, we report a Brassica rapa loss-of-function schengen3 (sgn3) mutant, braA.sgn3.a-1, which accumulates twice as much Mg and a third more Ca in its leaves. We mapped braA.sgn3.a to a single recessive locus using a forward ionomic screen of chemically mutagenized lines with subsequent backcrossing and linked-read sequencing of second back-crossed, second filial generation (BC2F2) segregants. Confocal imaging revealed a disrupted root endodermal diffusion barrier, consistent with SGN3 encoding a receptor-like kinase required for normal formation of Casparian strips, as reported in thale cress (Arabidopsis thaliaPlant physiologyMagnesium and calcium overaccumulate in the leaves of a schengen3 mutant of Brassica rapa.PMC8260142N1-0105BB/N023927/1J7-9398P1-0112BB/L002124/1P1-0212BB/L027739/2N7-0077N1-0090BB/G014159/1BB/G014159/2BBSSE200613215BB-G013969-1BB/J019631/1J7-9418BB/N004302/1Reyt GVogel-Mikus KHayden RIrwin JAPongrac PAlcock TDOstergaard LThomas CLWilson LStephenson PWilson MBroadley MRKing GJMoore CHammond JPSalt DEGraham NSO Lochlainn SKelemen MWhite PJfalseMagnesium and calcium overaccumulate in the leaves of a schengen3 mutant of Brassica rapa.Magnesium (Mg) and calcium (Ca) are essential mineral nutrients poorly supplied in many human food systems. In grazing livestock, Mg and Ca deficiencies are costly welfare issues. Here, we report a Brassica rapa loss-of-function schengen3 (sgn3) mutant, braA.sgn3.a-1, which accumulates twice as much Mg and a third more Ca in its leaves. We mapped braA.sgn3.a to a single recessive locus using a forward ionomic screen of chemically mutagenized lines with subsequent backcrossing and linked-read sequencing of second back-crossed, second filial generation (BC2F2) segregants. Confocal imaging revealed a disrupted root endodermal diffusion barrier, consistent with SGN3 encoding a receptor-like kinase required for normal formation of Casparian strips, as reported in thale cress (Arabidopsis thalia2021-01-01T00:00:00Z2021 Jul2026-04-30T03:12:54.97Z2022-02-11T13:04:46.507ZS-EPMC82601423383119010.1093/plphys/kiab150