ChileanJAR

The regulating effect of temperature on the phenology of wheat was determined by seedings performed at different dates. Results showed a systematic acceleration of development, as the seeding date is closer to summer. The cycle length is reduced to one half in the hottest period of the year, in relation to the normal seeding date, emphasizing the heavy regulating effect of temperature on the velocity of this species developmento Similarly, the maximum LAI reached by the crop was also decreased in summer seedings. The accumulation of degree-days in each development stage proved relatively constant, as well as indepent from the seeding date. Development velocity (1/time between two phenologic stages) exhibited a linear function of temperature. This experiment provided basic elements to interpret the effect of the relationships temperature-development on wheat yield.