Abstract

A field experiment was conducted at Instructional Farm of Soil and Water Engineering, College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh during summer season (February - May) 2012 to study the sesame response to moisture and thermal regimes with three factorial strip plot design; three factors are thermal regimes (date of sowing), moisture regimes (Irrigation interval) and use of mulch. The crop was exposed to different thermal regimes at four different dates of sowing that is, 1^st February, 14^th February, 1^st March and 14^th March with different moisture regimes by varying the irrigation interval (3, 4 and 5 days irrigation interval). Results revealed that the seasonal depth of irrigation moreover decreased with delay in sowing from 1^st February and the growing days requirement decreased with delaying sowing after 1^st February with irrigation water depth 380, 402, 356 and 355 mm, while growing degree days as 109, 94, 83 and 74 days. The more number of growing days were required to mature the crop with less total thermal heat units as 2152, 1946, 1803 and 1722 degree - days, respectively. The sesame yield is significantly influenced by the thermal regimes. The highest and lowest sesame grain yield of 1131.59 and 555.20 kg/ha was observed for the thermal windows of 16^th and 1^st February, respectively. The grain yield increased rapidly by delaying the sowing from 1^st to 21^st February then it decreased slowly and continously. The vegetative stage was found the most sensitive stage to thermal regimes followed by establishment stage, flowering stage, ripening stage and reproductive stage. The highest grain yield of 991.27 kg/ha was found under drip irrigation at 3-days interval which was higher by the tune of 10.33, 17.32 and 20.86% as compared to that of under 4, 5 days under drip and 7-days under surface irrigation, respectively.

Key words: Sesame, thermal regimes, moisture regimes, drip irrigation in sesame, mulching in sesame.