FITTING CROPPING TECHNOLOGY IN A CHANGING CLIMATE

Maize is one of the most important crops in the world.Its successful production depends mainly on meteorological factors.The aim of study was to define the most efficient tillage system (no-till, reduced or conventional tillage) and fertilizer amount (Ø, 330 or 660 kg ha -1 of N:P:K) for high maize yields (ZP 704) under rain-fed and irrigation conditions, according to the results of a longterm maize cropping experiment (1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010).The observed 20 year period was characterized by increasing trends of the average temperatures and sum of precipitation.A positive dependence between grain yield and precipitation was noticed only under rain-fed cropping.Weibull analysis emphasised that the highest yields were achieved with 330 kg ha -1 of N:P:K fertilizer and conventional tillage under unfavourable conditions.Negative meteorological factors were diminished under irrigation, where high inputs resulted in increased yields.However, rain-fed cropping is still the most abundant cropping practice in the world, and moderate inputs (330 kg ha -1 N:P:K) resulted in stability of the maize yield, regardless of the lower yields achieved.On the other hand, the high yields attained with high fertilizer and tillage inputs under irrigation could be reasonable only in seasons with low precipitation (drought).