RESOPNSE OF WHEAT (TRITICUM AESTIVUM) UNDER VARYING WEATHER ENVIRONMENT

摘要

A field experiment was conducted during Rabi 2007-08 and 2008-09 at Instructional Farm, Rajasthan College of Agriculture, Udaipur. The treatment comprises of four sowing dates (7th November, 19th November, 4th December and 19th December) and four irrigation levels (three, four, five and six). Result revealed that the magnitude of reduction in number of tillers/m row was more due to higher minimum temperature. The maximum heat units of 1701 degree days were recorded under 19th November sown crop with six irrigation (D_(2)I_(6)). The increase in 6.0 deg C mean temperature between 90 to 105 DAS caused reduction in number of effective tillers/m/row at 105 DAS by 15.0 per cent. The highest grain yield was obtained under 19th November sown crop (D_(2)) followed by 7th November sown crop (D_(1)) during both the years. The mean temperature experienced during heading to milking was in the range of 14.5-15.0 deg C. and 18.0-19.0 deg C during 2007-08 and 2008-09, respectively. The delay sowing caused reduction of 25.7 and 41.9 per cent grain yield in 4th December (D_(3)) and 19th December (D4) sown crop, respectively as compared to 19th November sown crop (D_(2)). The highest heat use efficiency for total dry matter and grain yield (8.94 and 2.74 kg/ha/deg C) was recorded under 7th November sown crop.