EFFECT OF IRRIGATION , NITROGEN AND PHOSPHOROUS ON PHYSIOLOGICAL STAGES OF SPRING SUNFLOWER.

Abstract

RESULTS OF FIELD EXPERIMENT CONDUCTED DURING 1992-1993 AT BARAUT ( MEERUT) TO STUDY THE EFFECT OF IRRIGATION , NITROGEN AND PHOSPHOROUS LEVELS ON PHYSIOLOGICAL STAGES OF SPRING SUNFLOWER( HELIANTHUS ANNUS L) ARE DISCUSSED. IRRIGATION APPLIED AT 0.8 IW/CPE RATIO EXHIBITED SIGNIFICANTLY MORE NUMBER OF DAYS FOR BUD FORMATION, COMMENCEMENT OF FLOWERING PEAK FLOWERING AND MATURITY OF CROP AS COMPARED TO 0.4 IW/CPE RATIO DURING BOTH THE YEARS OF THE STUDY. HOWEVER, IRRIGATION APPLIED AT 0.8 IW/CPE RATIO WITH REGARD TO THESE STATED CHARACTERS EXCEPT STARTING OF FLOWERING AND MATURITY , IRRIGATION APPLIED AT 0.4 AND 0.6 IW/ CPE RATIO DID NOT DIFFER SIGNIFICANTLY WITH REGARD TO NUMBER OF DAYS REQUIRED FOR BUD FORMATION BUT COMMENCING FLOWERING , PEAK FLOWERING AND MATURITY WERE FOUND SIGNIFICANTLY AFFECTED. NITROGEN APPLICATION ( 80 AND 120 kg/ha) INCREASED THE NUMBER OF DAYS TAKEN TO BUD FROMATION COMMENCING FLOWERING AND PEAK FLOWERING SIGNIFICANTLY OVER 40 kg/ha . APPLICATION OF 80 kg P /ha TOOK SIGNIFICANTLY MORE NUMBER OF DAYS FOR COMMENCING FLOWERING AND PEAK FLOWERING AS COMPARED TO WITHOUT P . IT IS INFERRED THAT MORE FREQUENT IRRIGATIONS AND HIGHER DOSES OF N AND P DELAY THE PHYSIOLOGICAL STAGES IN THIS CROP.