the Symposium on Wheats for More Tropical Environments - cimmyt

63Wheat Improvement Programsfor <strong>the</strong> Hotter Parts of IndiaJ.P. TandoD. Wheat Program.Indian Agricultural Research Institute. New Delhi. IndiaWheat is <strong>the</strong> most important coolseasonfood grain crop of India. During1983-84. wheat was cultivated on morethan 22 million hectares. producingabout 45 mUlion tons of grain. Thisrepresents a tremendous increase over<strong>the</strong> 6.46 mUlion tons of wheat grainproduced in 1950-51. During thisperiod. <strong>the</strong> productivity per hectare hasincreased from 663 kglha to more than1.800 kglha. The increased productivityis attributable partly to better irrigationfacilities and <strong>the</strong> increased use offertilizer; <strong>the</strong> major factor. however. is<strong>the</strong> popularization of high-yieldingdwarf wheats which have enabledefficient utilization of <strong>the</strong> createdresources. The figures for area.production and productivity over <strong>the</strong>period since Indian Independence aregiven in Table 1.The major wheat-growing states arePunjab. Haryana. Uttar Pradesh.IMadhya Pradesh. Rajasthan. Bihar.GUjarat. Maharashtra and West Bengal.Area production and yield per hectarein various wheat-growing states areshown in Table 2.Among <strong>the</strong> important wheat-growingstates. wheat in Karnataka.Maharashtra and Madhya Pradesh isgrown in a typical hot. tropical climate.In considerable areas of Gujarat. Bihar.West Bengal and Assam. wheat is alsocultivated in a fairly hot climate. Themaximum and minimum temperaturesduring <strong>the</strong> wheat crop season at fourlocations representing typical wheatgrowingareas of <strong>the</strong> country arepresented in Figure 1; averagetemperatures are presented in Figure 2.It is clear from <strong>the</strong>se figure that wheatis grown primarily in <strong>the</strong> coolestenvironments in <strong>the</strong> hills. followed by<strong>the</strong> northwestern parts of <strong>the</strong> country;in <strong>the</strong> east and south it is cultivatedunder much higher temperatures.Ano<strong>the</strong>r aspect which is clear from<strong>the</strong>se figures is that temperatures arehighest at times of planting andTable 1. Wheat area, production and yield, India, 1946-47to 1982-83Area Production VieldVear (000 ha) (000 tons) (kg/ha)1946-47 10,120 6,232 6161951·52 9,471 6,182 6531956-57 13,424 9,403 6951961-62 13,750 12,072 8901966-67 12,832 11,393 8871971-72 19,139 26,410 13801976-77 20,922 29,010 1387 41981-82 22,308 37,8331982-83 23,OOO~.I 42,500~.I1696 /1847!.!./ EstimatedSource: Area and Production of Principal Crops in India