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For studying the phenological behaviour of wheat, four wheat varieties viz., Lok-1, GW-190, GW173 and Raj. 3077 were evaluated under varying sowing dates and seed rates during rabi 1993–94. The results showed that the variety Lok-1 took significantly less time for initiation and completion of the various phenological stages as compared to the varieties GW-190 and Raj-3077, though it remained at par with GW-173 in this respect. Variety Lok-1 and GW-173 required significantly lower heat units for successive phenological stages as compared to GW-190 and Raj-3077. Late sowing (December 7) significantly increased the number of days required for initiation and completion of various vegetative growth stages while significantly reduced number of days required in reproductive phase. The early sown crop (November 9) needed significantly higher heat units (1775.96 degree days) to reach maturity stage which was significantly higher by 3.06 and 1.65 per cent over November 23 and December 7 sowing, respectively. Seed rates failed to produce significant difference in days required for initiation and completion of various successive growth stages of crop as well as heat unit requirements for occurrence of the various successive growth stages.