Irrigation management in wheat (Triticum aestivum L.) for maximizing water productivity

The present study was carried out to study the effect of irrigation management in wheat (Triticum aestivum L.) for maximizing water productivity during 2011-12, at Ayub Agricultural Research Institute (AARI) Faisalabad, Pakistan. Different parameters which are related to yield and yield components were studied. The results were analyzed in completely randomized block design with three replications and twenty treatments. The results obtained are summarized as under: Variations in number of irrigations at critical growth stages of wheat significantly affect the flag leaf area. The maximum (43.40 cm2) flag leaf area was recorded in T20 where five irrigations were applied at each growth stage of wheat and was significantly different from T16 (38.44 cm2) where four irrigations were applied at (crown root + booting + heading + milking stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the flag leaf chlorophyll contents. The maximum (33.4 mug cm2) chlorophyll contents were recorded in T20 where five irrigations were applied at each growth stage of wheat and was statistically at par with T19 (33.44 mug cm2) where four irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect relative water contents of flag leaf. The maximum (78.67%) relative water contents were recorded in T20 where five irrigations were applied at each growth stage of wheat and was statistically at par with T19 (78.17%) and different from T18 (76.61 %) where four number of irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect canopy temperature. The maximum (45.64 degree C) canopy temperature was recorded in T1 where no irrigation was applied and was significantly different from T2 (42.74 degree C) where one irrigations were applied at crown root stage. Variations in number of irrigations at critical growth stages of wheat significantly affect the number plant height. The maximum (85.85 cm) plant height was recorded in T20 where five irrigations were applied at each growth stage of wheat and were statistically at par with T19 (85.69 cm) where 4 numbers of irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the number of tillers per unit area. The maximum (402) number of tillers m-2 was recorded in T20 where five irrigations were applied at each growth stage of wheat and was significantly different from T19 (399) where four irrigations were applied (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the number of fertile tillers per unit area. The maximum (383) number of fertile tillers m-2 was recorded in T20 where five irrigations were applied at each critical stages of wheat and were statistically at par with T19 (382) where four irrigations were applied (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significant affect the spike length per spike. The maximum (10.44 cm) spike length was recorded in T20 where five irrigations were applied at each critical stages of wheat and was significantly different from T19 (9.36 cm) where four numbers of irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the number of spikelets per spike. The maximum (19) number of spikelets per spike was recorded in T20 where five irrigations were applied at each growth stage of wheat and were significantly different from T19 (17) where four irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the number of kernels per spike. The maximum (39 g) number of kernel per spike was recorded in T20 where 5 irrigations were applied at each growth stage of wheat and was significantly different from T19 (35 g) where four irrigations were applied at (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect 1000-grain weight. The maximum (38.38 g) 1000-grain weight was recorded in T20 where five irrigations were applied at each growth stage of wheat and was significantly different from T19 (37.58 g) where 4 irrigations were applied (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect biological yield. The maximum (11.41 t per ha) biological yield was recorded in T20 where five irrigations were applied at each growth stage of wheat and was significantly different from T19 (11.16 t per ha) where four irrigations were applied (crown root + stem elongation + heading + milking stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the economic yield. The maximum (4.69 t per ha) economic yield was recorded in T20 where five irrigations were applied at each critical stages of wheat and was significantly different from T19 (4.45 t per ha) where four numbers of irrigations were applied (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the harvest index. The maximum (41.10 % harvest index was recorded in T20 where 5 irrigations were applied at each growth stage of wheat and was significantly different from T19 (39.87 %) where 4 irrigations were applied (crown root + stem elongation + booting + heading stage). Variations in number of irrigations at critical growth stages of wheat significantly affect the protein contents. The maximum (13.67%) grain protein contents percentage was recorded in T1 where no irrigation was applied and was significantly different from T2 (13.67 %) where one irrigation were applied at crown root stage. Variations in number of irrigations at critical growth stages of wheat significantly affect the gluten contents. The maximum (28.11%) grain gluten contents percentage in T1 where no irrigation was applied and was significantly different from T2 (27.09%) where one irrigations were applied at crown root stage.