ABSTRACT

Maize, wheat and rice are the primary cereal grain crops in the world and approximately equal quantities of each are produced. Total world production of maize in 1975 was 323 million metric tons. Maize is used predominantly as a feed for animals, but it is used extensively for human food and in industry. Maize enters into industrial use as paper products, construction materials, textiles, metal castings, pharmaceutics, ceramics, paints, and explosives. Maize grain yields greater than 10.000 kg/ha have been produced under optimum conditions. Chemical analyses of maize leaves from plants growing in the field provide very useful information concerning the availability of different nutrients to the plants. Yield differences among maize hybrids at any one fertility level or resulting from fertilizer applications are often observed. Insect pests and diseases reduce nutrient absorption to maize or otherwise reduce crop growth and yield. Cultural practices to control weeds, insects, and diseases are essential for effective maize production.