Maize

• Maize is warm weather plant that requires high temperature during the growing period and can be grown from sea level to 4000 m above sea level.
• Maize produces good results when the growing season is more than 140 days, with the mean day temperature of around 24oC and night temperature above 15oC (Martin and Leonard, 1967).
• No maize cultivation is possible in areas where the mean temperature is below 190C or where the average night temperature during three summer months falls below 20C.
• Low temperature reduces growth and extremely high temperature may retard germination of seeds, particularly when it is combined with deficient moisture. Maize seed can germinate at 7oC.
• The optimum temperature for germination is 210C and for growth 320C. If at the time of planting soil temperature is low and outlook is for continued moist and cool weather, maize yield is reduced.
• The optimum day and night temperature for vegetative growth of crop lies around 30 to 35oC (day) and 23 to 25oC (night). The temperature of -2 to -3oC prevailing for a few days during tasseling and the milk stage of crop destroys it.
• Excessively high temperatures are also harmful at this stage. If temperatures remain above 32oC during noon hours for several days, pollen is desiccated and yield is drastically reduced.
• Maize is classified as short day or day neutral plant.
• Since Maize is a C4 plant, it is photosynthetically more efficient, which needs bright sunny days for the acceleration of photosynthesis in any stage of plant.
• It needs about 75 cm of rainfall during its life period. Maize can be grown successfully in areas having average of 700 mm well distributed rainfall throughout its growth period. Maize may tolerate an annual rainfall of 2500 to 4000 mm rainfall provided the field does not get flooded. Water logging is hazardous for crop at any growth stage.