The Ides of March return to haunt

This year, we are witnessing a repeat — though with significant differences.

The current rain — again, courtesy a low pressure depression induced by western disturbances over north Pakistan and the adjoining Jammu & Kashmir regions — started from March 11 night, and has now more or less stopped. While there have been reports of strong winds, thunderstorms and hail this time too, they seem confined to isolated places over northwest India, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand and Odisha.

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But the big worry is the Met Department’s warning of a fresh western disturbance affecting the western Himalayan region from Wednesday night and over the adjoining northwest Indian plains the following day. The impact of the wet spell, both current and the one forecast, would be largely on the wheat due for harvesting from next month.

The wheat crop is currently in the ‘milk’ or ‘early dough’ stage in most of India. This is the period when flowering is already complete and grain formation/filling — accumulation of starch matter in the kernels — has just about begun. Rain now isn’t bad really, so long as it is gentle showers that help keep the mercury from rising. Ideally, day temperatures should remain within 35 degrees Celsius throughout March. Any sudden spike could lead to premature drying and ripening of the grain. The usual thumb rule here is that every extra day on the field during the grain-filling stage confers an additional wheat yield of 45-50 kg per hectare.

This is precisely what happened in 2014, when wheat production hit a record 95.85 million tonnes (mt) on the back of an extended winter. Last year too, India looked set for a bumper harvest before the untimely heavy showers with strong winds and hail led to largescale lodging of the crop. As a result, production, which in February 2015 was estimated at 95.76 mt, was revised downwards to 86.53 mt.

“There hasn’t been any widespread lodging reported this time so far. In some areas, partial lodging has happened. But even this crop can recover if the skies clear, which they have today, and there are no further heavy rains,” says R K Gupta, acting director of the Indian Institute of Wheat & Barley Research at Karnal, Haryana.

The negative production impact from “five per cent crop lodging”, according to him, can be more than offset if the “remaining 95 per cent” wheat benefits from the lowering of temperatures, which, until last week, was about 5 degrees above normal. These could have well led to the crop maturing 7-10 days early and translating into a yield loss of roughly half-a-tonne per hectare, or 13-14 mt in all. That can have serious implications when wheat stocks in government godowns are at a seven-year-low (see chart), although they are still above the normative minimum requirement of 7.5 mt at the start of the new marketing season from April 1.

The impact of the rain is seen to be less in mustard, where over 70% harvesting is complete. “Only the standing crop sown late, towards the first week of November (as against the normal time of October 15-25), may have suffered damage in some parts. On the whole, we expect a bumper crop, especially with no major incidence of stem rot, white rust or alternaria blight this year,” says Dhiraj Singh, who heads the Directorate of Rapeseed-Mustard Research at Bharatpur, Rajasthan.

There is some concern with regard to rabi pulses, particularly chana. While the crop in western and southern India was already harvested by February-end, this is not the case in MP, UP, Rajasthan and Chhattisgarh. The crop here is still either in the field or lying on the threshing floor after having been harvested.

“The standing crop is prone to pod shattering, when you have heavy rains followed by sudden drying due to sunshine. Even the harvested grain that has not been threshed can suffer quality deterioration, or germinate,” notes Narendra Pratap Singh, director, Indian Institute of Pulses Research, Kanpur.

As of now, the damage to the rabi crop from the unseasonal March rain appears to be not as bad as last year, though there may be individual farmers who would have been as, if not more, affected. Whether there is more to come will be known after March 18.