To deal with the decline in the underground water table, Punjab Agricultural University (PAU) has come up with a device called the ‘tensiometer’, which can keep a check on water requirement in paddy fields. According to experts, its use helps promote efficient irrigation that can save 25-30% water.
“Each year, during the paddy season that requires continuous irrigation right from sowing in early June till the crop fully matures by September end, it easily consumes about 67% of the total irrigation water used in the state. However, if every farmer starts using tensiometer, it can save lot of water, one of the most precious natural resources,” said MS Kahlon, a soil scientist at PAU.
To develop this device, it took 10 years for the retired, 67-yearold scientist Gurdev Singh Hira, a former additional director of research at PAU. He said, “Being a scientist, the declining water table always worried me. Before I retired, every water survey that I read indicated that in Punjab, the during paddy season, there is more pressure on water resources. So, I came up with this device.”
“According to the field experiments, it saves farmers from putting unnecessary pressure on different water resources and helps scheduling irrigation as per need. In 2013-end, the device was patented,” Hira added.
The device is simple to use and consists of two transparent acrylic tubes, one inserted in the other. Before it is inserted in the field, it should be filled with water. The side of the device marked with green, yellow and red labels has to be up. Within a few hours, it unfolds the result. If water touches the green label, there is no need to irrigate the field for the next two days; but if it goes down the green, there is an immediate need of irrigation.
The tensiometer should be installed at a leveled spot and 8 inch deep in the field. Also, it should be at least three meters away from the irrigation channel. Most importantly, it must be ensured that the upper cap of the tube is tightly closed with a silicon cork so that air pressure can be maintained in the device.
“Using this device is the need of the hour. PAU is currently researching to develop it further for using it in other crop and vegetable fields,” said JS Dhiman, additional director of research, PAU.