root exudate 2',3',4',5',6' pentahydroxychalcone 2 2′,3′, 4′,5′,6′-Pentahydroxy chalcone 2 3,5,6,7,8 pentahydroxy 4' methoxyflavone 2 3,5,6,7,8 pentahydroxyflavone 2 3,5,6,7,8-Pentahydroxy flavone 2 3,5,6,7,8-Pentahydroxy-4′-methoxy flavone 2 Brassica 2 Brassica alba 2 Brassicaceae 2 Chalcone 2 Chalcones 2 Cruciferae 2 Flavones 2 Flavonoids 2 Magnetic Resonance Spectroscopy 2 Mass Spectrometry 2 Molecular Structure 2 Mustard Plant 2 Plant Roots 2 Plant Shoots 2 Root exudates 2 Roots 2 Shoots 2 Sinapis alba 2 Spectrophotometry 2 apigenin 2 article 2 brassica alba 2 controlled study 2