QUALITATIVE VARIATION IN ONION UNDER INFLUENCE OF SULPHUR FERTILIZATION AT THREE DIFFERENT PERIODS

Abstract

An investigation was carried out at the Horticultural Research Farm of Babasaheb Bhimrao Ambedkar University, Lucknow during rabi season of 2013-14. Two sources of sulphur (gypsum and elemental sulphur) having three different doses (20, 40 and 60 kg/ha) of each were applied at three different time period viz., 15th Nov. 2013, 15th Dec. 2014 and 15th Jan. 2014 to asses qualitative traits of onion laid out in factorial RBD. The observation shows that 40 kg/ha of elemental sulphur applied at 15th Nov. produces good quality of bulbs having higher ascorbic acid (14.02 mg/100g) content while 60 kg/ha of elemental sulphur in 15th Nov. increases the TSS (16.87 0Brix) and Significantly higher content of reducing sugar (5.74 %), and total sugars (12.52 mg/100g) were found at applica tion of low dose of elemental sulphur i.e., 20 kg/ha at 15th Nov. and non-reducing sugar (7.30 %) was observed in 15th Dec. transplanting whereas maximum pyruvic acid content (7.97 µmol/g) was found in high dose of elemental sulphur 60 kg/ha applied at 15th Jan. 2014. late transplanting (15th Jan) and high sulphur dose (60 kg/ ha) produces pungent onion while early transplanted (15th Nov.) bulb with low sulphur dose (20 kg/ha) are less pungent.