The proposed work was conducted at S.G.R.R (P.G) College, Dehradun, Uttarakhand. 2017-18. The experiment was laid out in split plot design with three replications. The main plot treatments consisted of three irrigation levels viz., No-post sowing irrigation (I0), one irrigation at 35 Days after sowing (I1) and 2 irrigations at 35 and 70 Days after sowing. The sub-plot treatments consisted of three row spacings viz., 15 cm, 25 cm and 35 cm. Yield of mustard is greatly control by irrigation and better results both in terms of biometric components and seed yield can be achieved by the application of optimum irrigation. Deficiency of enough irrigation water as per requirements of mustard crop causes moisture stress at critical stages of growth and development. Under such circumstances to find out some appropriate solution for minimizing the irrigation requirement of mustard crop without reduction yield should receive top most concern.

Soil moisture content in I2 treatment was higher than in I1 and I0 treatments. That is lowest moisture content of 28.0%, 33.2% and 35.2% at harvest was recorded in I0, I1 and I2 treatments. Among row spacing, soil moisture content was recorded higher throughout the growing season in 35 cm (S3) row spacing than 25 cm (S2) and 15 cm (S1). The lowest moisture content of 26.6%, 34.1% and 35.2% at harvest was recorded in S1, S2 and S3 treatments, respectively.