A field experiment was conducted to evaluate the Impact of irrigation levels and bio-regulators on growth and yield attributes of Indian mustard (Brassica juncea L.). The experiment comprised three irrigation levels: no post-sowing irrigation (control), one irrigation at 40 days after sowing (DAS) and two irrigations at 40 and 75 DAS along with five bio-regulator treatments: water spray (control), GA3 @ 50 ppm at 50% flowering stage, Thiourea @ 500 ppm at 50% flowering stage, GA3 @ 50 ppm at 50% flowering + 50% Pod formation stage and Thiourea @ 500 ppm at 50% flowering + at 50% Pod formation stage. The results revealed that two irrigations at 40 and 75 DAS significantly enhanced plant height, number of branches, dry matter accumulation, yield attributes viz., siliquae plant-1, seeds siliqua-1, siliqua length compared to one irrigation and control. However, application of thiourea @ 500 ppm at 50% flowering + at 50% Pod formation stage outperformed other bio-regulators, showing significant improvement in growth as well as yield attributes. Whereas, statistical analysis indicated that irrigation levels not exerted a significant influence on plant stand and days required to 50% flowering a well as foliar application of bio-regulators did not exert any significant effect on plant stand, test weight and days required to 50% flowering and maturity.
