EFFECT OF BIOFERTILIZERS IN PRESENCE OF FERTILIZER NITROGEN ON YIELD AND QUALITY OF SUGARCANE (SACCHARUM-OFFICINARUM)

A field experiment was conducted during 1989-90 and 1990-91 on a medium black soil at Sehore to test the efficacy of 2 biofertilizers (Azospirillum brasilense Tarrand, Krieg & Dobereiner and Azotobacter chroococcwn Beijerinck) in combination with different levels of nitrogen to economize the quantity of fertilizer nitrogen for 'Co7318' sugarcane (Saccharum officinarum L.). Azospirillum brasilense was applied as sett inoculation as well as soil application, whereas Azotobacter chroococcum was applied through soil alone. Application of 75% N of the recommended dose as inorganic fertilizer (225 kg N/ha) along with soil incorporation of Azotobacter gave as much cane yield as with 300 kg N/ha as inorganic fertilizer alone. Application of Azotobacter gave 7.7-15.2% more yield than Azospirillum at all the inorganic N levels. Juice quality was not affected by the fertilizer treatments. Use of biofertilizers in sugarcane proved economical in saving 25% inorganic nitrogen (75 kg N/ha).