For adopting a particular cropping plan, the time of onset of monsoon is the most important single parameter but it has not been considered in most of the studies conducted for crop planning under rainfed regions. Rainfall data of Bhilwara district in Rajasthan state for a period of 57 years were analysed from two approaches viz.; „Meteorological‟ approach and „Onset of monsoon‟ approach. The „Meteorological‟ approach is a conventional approach wherein the information for crop growth period is assumed based on normal week of onset of monsoon and also provides a single set of information which leads to a single set of cropping plan irrespective of time of onset of monsoon. On the contrary in the „Onset of monsoon‟ approach, the rainfall data are arranged by considering onset of monsoon as datum and also grouped for different weeks of onset of monsoon. The results reveal considerable difference in rainfall characteristics with respect to length of growing period, water surplus/ deficit and probability of intervening dry spells due to these approaches. | Contingent crop planning for proactive monsoon management under rainfed regions
