Insufficient rains in Southeast Asia, meanwhile, could dent supplies of palm oil, the world's most widely used vegetable oil, while extreme weather in top corn and soybean importer China is putting food output at risk.

The national capital Delhi and surrounding areas are enveloped in a layer of smog each winter as cold, heavy air traps construction dust, vehicle emissions and smoke from the crop stubble burning.

The world's most polluted capital is blanketed in smog every winter as cold, heavy air traps construction dust, vehicle emissions and smoke from the burning of crop stubble to clear the fields for the next crop.

Economists say annual headline inflation will likely start easing from September's peak because of a jump in the index in corresponding months last year, but price pressures on grains, vegetable and milk will persist.

More than 70 days of extreme temperatures and low rainfall have wreaked havoc along the basin of the Yangtze, which supports more than 450 million people as well as a third of the country's crops.

India is the world's biggest exporter of rice, a staple for Asia, and monsoon rains determine the size of the country's rice crop.

One significant advantage of increased crop yields is to reduce the need for forests to be cleared for food production.