Metabolomic Changes in Onion Incited with Twister Disease

Twister disease has become epidemic on onion crop in the recent years, in coastal tract and major onion growing districts in Karnataka. This disease C. gloeosporioides, F. oxysoprium and M. graminicola are causing heavy yield loss. The metabolomic changes due to infection at different stages by colorimetric assay revealed the reducing sugar, nonreducing sugar and total sugar were higher in 5^th grade (8.74, 6.68 and 15.54 mg/g of leaf tissue) whereas, total proteins were higher in 1^st grade (9.92 mg/g of leaf tissue). As for as growth regulators are concerned IAA and GA were highest in 3^rd grade (16.50 and 3.29 mg/g of leaf tissue). The HPLC analysis of IAA content was higher in 3^rd grade diseased leaves which is of 5.14 mg/g of leaf tissue whereas, lowest in healthy seedling stage (2.38 mg/g of leaf tissue). The GA content was higher in 3^rd grade diseased leaves were which is of 4.17 mg/g of leaf tissue. Whereas lowest in healthy (3.16 mg/g of leaf tissue).