EFFECT OF IRRIGATION METHODS FOR CAULIFLOWER GROWN IN HEAVY SOIL WITH SHALLOW WATER TABLE

Abstract

A field experiment was conducted on performance of cauliflower (Brasica oleracea Var. botrytis) cultivars 'Pusa Dipali', 'H-I' and 'Snow Ball' during winter season of 1985, 1986 and 1988 to study the effect of drip, surface and waterable subsurface irrigation methods. The drip and surface irrigations were scheduled based on depth of irrigation to class A pan evaporation ratio (IW:CPE). The IW: CPE ratios for drip irrigation were 0.6, 0.4 and 0.2, where as for surface irrigation 1.0, 0.6 and 0.4. The surface and drip irrigations were done with good quality water and saline tubewell water, whereas, watertable subsurface irrigation was done only with good quality canal water and the water supply was continuous. The considerable capillary contribution from shallow watertable depth kept the soil moisture close to field capacity and thus crop was never subjected to excessive water stress even under surface irrigation. The favourable soil moisture and crop environmental conditions resulted in higher crop yield under surface irrigation compared to drip irrigation. The highest curd yield (7560 kg/ha) during 1988 was obtained under water table irrigation. The leaf yield was higher than the curd yield and the ratio of curd: leaf yield varied from 1:1.2 to 1 :4.2. The curd and leaf yields tor 'H-1' during 1986 was higher than 'Pusa Dipa1i' during 1985 and 'Snow Ball-16' during 1988. The dry matter% increased to the maximum value and then decreased with time after planting. The values were higher tor curd than that for leaf during initial harvesting; however, the trend was reversed later. The curd formation for 'Snow Ball-16' during 1988 was the fastest under watertable irrigation and the 'slowest under surface irrigation.