Moisture depletion pattern and penultimate depression under cost-free surge irrigation in sunflower (II)

摘要

Cost-free surge irrigation method was tested involving two amendments of Farm Yard Manure (FYM) and Raw Coconut Fibre Waste (RCFW) @ 12.5 t ha~(-1) in sunflower crop. The cultivar was Co.2 raised with a spacing of 60 X 2 = 30 X 30 cm under double row planting. Cost-free surge irrigation includes waste aluminium sheets of off-set press made into inlet pipes of 52 X 6 cm and placed in the head channel to draw the water The designed rate of flow was 1 lps and the 'ON-OFF' time was 10 minutes. The study revealed that the available soil moisture (ASM) was higher in the head and gradually decreased upto third sector and again increased in the fourth sector. Available soil moisture status was higher under RCFW as compared to FYM. There was not much difference in depletion pattern between surge and continuous flow. There was a marked reduction in the moisture status in third sector (51-75 M). Under farmers' method the depletion pattern did not vary as compared to surge or continuous flow. Soil moisture depletion was taster during the initial periods and was slowed down during later periods.