The experiment was conducted at the experimental field of Irrigation and Water Management Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur during rabi season of 2013-2014. The soil of the experimental field was sandy clay loam with a pH value of 6.49. The field capacity and wilting point of the experimental field were 28.5 % and 14.4 % (wet basis), respectively. The bulk density was 1.50 g/cc. The experiment was laid out in a Randomized Complete Block Design (RCBD) with two factors comprising two levels of irrigation and three levels of fertilizer doses. There were six treatments in the experiment and the treatments were replicated thrice. The unit plot size was 2.5m × 2.5m with recommended plant spacing of 50 cm × 50 cm. The treatments were:
T1= Drip irrigation at 3 days interval with fertilizer does N110, P40, K100 and S25 kg/ha
T2= Drip irrigation at 2 days interval with fertilizer does N75, P40, K75 and S25 kg/ha
T3= Drip irrigation at 2 days interval with fertilizer does N110, P40, K100 and S25 kg/ha
T4= Drip irrigation at 3 days interval with fertilizer does N75, P40, K75 and S25 kg/ha
T5= Drip irrigation at 2 days interval with fertilizer does N50, P40, K50 and S25 kg/ha
T6= Drip irrigation at 3 days interval with fertilizer does N50, P40, K50 and S25 kg/ha
Total amount of P in the form of triple super phosphate and other micronutrients were applied during final land preparation while the different doses of N and K in the form of urea and muriate of potash were applied with irrigation water into 4 equal splits. Cowdung was applied at the rate of 5.0 t/ha. Strawberry variety FA-016 (Advanced line) was used for the study. The strawberry seedlings (produced by tissue culture) of 20-25 days old were transplanted on 09 October 2013. For mulching, paddy straw @ 5.0 t/ha was used after one month of transplanting. Application rate of drip irrigation system depends on the discharge rate of the dripper. The dripper discharge was measured for optimum operating pressure and average discharge was found to be 1.72 lit/hr. Irrigation was applied through drip system according to the treatments to meet the crop evapotranspiration (ET). Time of water application was calculated by dividing the volume of required water by the average emitter discharge. The dripper emission is assumed uniform. The depth of irrigation water applied per plant was calculated using the formula (Ucar et al., 2011):
I = A × Ep × Kcp × P, Where,
I = Irrigation water amount (lit)
A = Area of plant (m2) = Row spacing (m) x Plant spacing (m)
Ep = Cumulative pan evaporation in the irrigation intervals (mm)
Kcp = Crop-pan coefficient
P = Percentage of wetted area
Strawberries were harvested from 03 February to 07 April, 2014. Data were analyzed statistically using MSTAT-C and the differences in mean were evaluated by Least Significant Difference (LSD).