Decision Support System for Optimizing Irrigation in Rice

The software has been developed with a view to calculate precise amount of irrigation water and decide the actual date of irrigation to be given to kharif rice based on climate, crop and soil. This constitutes a part of precision agriculture. Water is a very important natural resource, which should be used judiciously in agriculture. In the recent years, occurrence of frequent dry spell during kharif season has become common due to erratic monsoon. This is affecting the production potential of the kharif rice in Bihar as well as all rice growing areas of the country. So, the application of right quantity of water for irrigation is essential for enhancing the water use efficiency in the crop and also it prevents excess use or loss. Another thing is that the farmers do not have any reliable and effective technique about actual time/date of irrigation. This software has been designed to give practical solution in this direction.

The software consists of three modules viz. i) calculation of irrigation requirement for puddling operation ii) calculation of irrigation requirement for the period of one week after puddling and iii) calculation of irrigation requirement for the period from one week after puddling till physiological maturity. In the model, no irrigation has been considered after physiological maturity of the crop. The model used in this software is based on the simulation of water balance (2002-2016) and field experimentation on kharif rice grown at Pusa (25.98° N, 85.67° E, 52 m amsl), Samastipur, Bihar.

To run the model, it is essential that one should know field capacity, permanent wilting point, and available water holding capacity, seepage and percolation rate of the farm soil as primary requirements. Software users should have information on only two meteorological parameters viz. daily rainfall and evaporation rate for calculation of irrigation requirement and deciding the actual date of irrigation.