Online Resource 3. EI mass spectra of unknown components 1-25. Mass spectra were deconvoluted from a GC/EI-QMS profile obtained from the polar fraction of a methoximated/trimethylsilylated root extract of Arabidopsis thaliana using AMDIS 2.7.

C12H21NO3Si2 (1) RI(ALKANE) = 1062, RI(FAME) = 735

C9H21NO2Si (2)RI(ALKANE) = 1134, RI(FAME) = 811

C8H21NO3Si2 (3)RI(ALKANE) = 1143, RI(FAME) = 820

C11H27NSi2 (4)RI(ALKANE) = 1175, RI(FAME) = 854

C12H20N2O2Si (5)RI(ALKANE) = 1182, RI(FAME) = 860

C10H24O4Si2 (6)RI(ALKANE) = 1214, RI(FAME) = 894

C13H23N2O3Si (7)RI(ALKANE) = 1254, RI(FAME) = 932

C9H19NO2Si (8)RI(ALKANE) = 1275, RI(FAME) = 954

C11H25O4Si2 (9)RI(ALKANE) = 1419, RI(FAME) = 1097

C10H23O4Si2 (10)RI(ALKANE) = 1443, RI(FAME) = 1122

C12H30N2OSi2 (11)RI(ALKANE) = 1470, RI(FAME) = 1148

C12H28N2O3Si3 (12)RI(ALKANE) = 1532, RI(FAME) = 1205

C10H19NS (13)RI(ALKANE) = 1647, RI(FAME) = 1320

C11H11N2O (14)RI(ALKANE) = 1758, RI(FAME) = 1427

C15H34O5Si3 (15)RI(ALKANE) = 1806, RI(FAME) = 1477

C16H34O7Si3 (16)RI(ALKANE) = 1886, RI(FAME) = 1561

C16H36O6Si3 (17)RI(ALKANE) = 1888, RI(FAME) = 1562

C21H52O5SSi5 (18)RI(ALKANE) = 2068, RI(FAME) = 1737

C17H27NO5Si2 (19)RI(ALKANE) = 2072, RI(FAME) = 1741

C14H18N2OSi (20)RI(ALKANE) = 2096, RI(FAME) = 1770

C9H19NOSSi (21)RI(ALKANE) = 2111, RI(FAME) = 1784

C23H48O4Si (22)RI(ALKANE) = 2613, RI(FAME) = 2267

C21H41NO (23)RI(ALKANE) = 2655, RI(FAME) = 2309

C25H52O4Si (24)RI(ALKANE) = 2797, RI(FAME) = 2458

C28H42O6Si2 (25)RI(ALKANE) = 2985, RI(FAME) = 2691