Based on climate and disease prevalence, particularly rusts, the country is divided into five major wheat zones: 1. North-Western Plains Zone 2. North-Eastern Plains Zone 3. Central Zone 4. Peninsular Zone 5. Northern Hills Zone.
1. North-Western Plains Zone:
It comprises Punjab, Haryana, Delhi, western UP, Rajasthan (except Kota and Udayapur divisions), foothills of Uttaranchal, HP and J & K. This is the most important among the major zones and accounts for about 40 per cent of area and 55 per cent of wheat production in the country.
This zone has longest and coolest winter in the plains and the duration of timely sown crop may extend beyond 145 days, making it potentially the most productive region. Ideal sowing time is mid- November and around 95 per cent area is under irrigation. Rusts are the major problem. Till recently, T. aestivum used to be the exclusively grown variety, but now some area is under T. durum in Punjab.
2. North-Eastern Plains Zone:
It comprises Bihar, Eastern UP, WB, Orissa, Assam and other north-eastern states. It has shorter winters and the crop duration is around 125 days. This is an exclusively T. aestivum zone and the productivity is relatively low. It accounts for nearly 30 per cent of the area and 25 per cent of production. Most of the wheat crop is preceded by rice. Wheat sowing is delayed up to November/December due to delayed harvest of rice crop.
3. Central Zone:
MP, Gujarat, Kota and Udayapur divisions of Rajasthan and Jhansi division of UP are included in this zone. This is the third important zone of the country accounting for 20 per cent of area and 15 per cent of production. Crop duration is relatively shorter (about 120 days). Both bred and durum wheats are grown.
This region is famous for quality wheat grain production. The best quality durum wheat is from this zone. About 30 per cent of wheat is rainfed and is sown in October. Irrigated wheat is normally sown in mid-November.
4. Peninsular Zone:
It comprises Maharashtra, Karnataka, AP and TN. It contributes to less than 5 per cent area and around 2 per cent wheat production. All the three species (T. aestivum, T. durum and T. dicoccum) are grown. Crop duration is shortest (about 110 days) due to short and warmer cool season.
About 87 per cent of wheat grown in Maharashtra is irrigated as against 25 per cent in Karnataka. Rainfed wheat is sown in mid-October and irrigated wheat during first fortnight of November.
5. Northern Hills Zone:
Hilly areas of Uttaranchal, HP, J & K, WB, Arunachal Pradesh and Sikkim constitute this zone. Wheat is grown up to an elevation of 3,500 m above MSL. T. aestivum is the only species grown. About 2 per cent area and 1 per cent wheat production is from this zone. Most of the crop is grown under rainfed conditions.