THE POTENTIAL effects of climatic change impose great challenges on agriculture scientists to diminish expected detrimental consequences of global warming. Two available databases, with results and observations of the last ten full seasons from 1997 to 2006 of maize national campaign and meteorological records of the same period databases were used to establish preliminary models illustrating climatic factors affecting maize grain yield. Five models were restricted for maize hybrids, i.e. SC.10, SC.155, TWC.324 and Nefertity hybrid in addition to a general model for maize hybrids deduced from an average performance of 20 maize hybrids either single or three way crosses. Data of grain maize yield production were collected by scientific teams who monitored demonstration fields distributed over 17 governorates during 10 years, where the recommended technological package was accurately executed.
The polynomial models that deduced depending on growing degree days (GDD) and their base temperatures as well as air relative humidity (ARH) illustrated at least 99% of the variance in the maize productivity over governorates and years. Forecasting the potential impact of climate changes on maize grain yield under some scenarios of global warming predicted slightly decrease due to temperature increase and low ARH percentage. Maize grain yield productivity will be slightly declined in some governorates as Aswan. By contrast, ARH increments give quite satisfactory relief effects from heat increasing.