Effect Of Sulphur Deficiency On Glucosinolate Content In Brassica Napus

Glucosinolates are a group of plant secondary metabolites containing abundant nitrogen (N) and sulphur(S) mainly in Brassica.The objective of this study was to investigate the effect of sulphur deficiency on gluconsinolate content in different part of leaves and root of Brassica napus.In this study,we used HPLC to analysis and quantified glucosinolate in different part leaves and root of Brassica napus.The result shows that glucosinolate composition in youngest leaves is same to root,they are Progoitrin(2-hydroxy-3-butenyl-,2OH3B),Glucoraphanin(4-methylsulphinylbutyl-,4MSOB),Glucoalyssin(5-methylsulphinylpentyl-,5MSOP), Gluconapin(3-butenyl),Glucoiberin(3-methylsulphinylpropyl,3MSOP),Glucocochlearin 6 kinds of aliphatic glucosinolates,and Glucobrassicin(Indol-3-yl-methyl-,I3M), Neoglucobrassicin(1-methoxyindol-3-ylmethyl-,1MTI3M),4-Methoxyglucobrassicin(4-methoxyindol-3-yl-methyl-,4MTI3M) 3 kinds of indole glucosinolates,But we can find 8 kinds of glucosinolates in oldest and middle leaves,except 3MSOP.There was a clear difference in the glucosinolate content in different leaf tissues of Brassica napus which were planted for five weeks,the youngest leaves contained 0.72μmol/g FW,whereas the middle and oldest leaves contained 0.31 and 0.17μmol/g FW,respectively. The root contained abundant glucosinolate(0.96μmol/g FW),especially indole gluconsinolate (0.67μmol/g FW).Total glucosinolate content in oldest leaves was not affected by sulphur deficiency treatment,whereas it decreased significantly in middle and youngest leaves at d 16 and d 14 after treatment,respectively.There was also significantly change in glucosinolate content in root of Brassica napus which was sulphur deficiency treated for 9 d.The aliphatic glucosinolate content in youngest leaves is more sensitive to sulphur deficiency than in root, but the indole glucosinolate content is more sensitive than youngest leaves.This study also analysis individual gluconsinolate content in Brassica napus response to sulphur deficiency.In youngest leaves,3-butenyl was most sensitive to sulphur deficiency treatment,but 2OH3B content was affected most by sulphur deficiency.In root,I3M was most sensitive to sulphur deficiency treatment,but 1MTI3M content was affected most by sulphur deficiency.