Dry-matter partitioning of late sown wheat under different irrigation schedules

A field experiment was conducted during winter season of 1995-97 at Ranchi on sandy-loam soil in randomized block design to study the effect of irriga tion on dry-matter partitioning and yield of late sown wheat (Triticum aest ivum L. emend. Fiori & Paol.). Treatment consisted of 11 irrigation schedul es based on frequency and critical growth stages, viz 4 irrigations at (i) crown root initiation + maximum tillering + boot + milk; 3 irrigations at ( ii) crown-root initiation + maximum tillering + boot; (iii) crown-root init iation + boot + milk; (iv) crown-root initiation + maximum tillering + milk ; (v) maximum tillering + boot + milk and 2 irrigations at (vi) crown-root initiation + maximum tillering; (vii) crown-root initiation + boot; (viii) crown-root initiation + milk; (ix) maximum tillering + boot; (x) maximum ti llering + milk and (xi) boot + milk. Wheat with 4 irrigations gave 27.2 and 64.5 % more grain yield than the crop with 3 (2 128 kg/ha) and 2 (1 646 kg /ha) irrigations respectively. Water-stress at maximum tillering and milk s tages drastically reduced the grain yield by 34.7 and 25.9 % respectively c ompared with the crop with 4 irrigations (2 707 kg/ha). Similarly crop with 4 irrigations accumulated 60.2 % of total dry-matter (1 089 g/m(2))in spik e, 34.9% in stem and only 5% in the leaves at maturity.. Moisture stress at maximum tillering caused maximum reduction in total dry-matter production (23.8 %) as well as spike dry-matter partitioning by approximately 4%.