INFLUENCE OF DIFFERENT SOURCES OF WATER FOR IRRIGATION ON PEPPER (Capsicum annuum L.) YIELD IN GLASSHOUSE CONDITIONS

The aim of this paper was to determine the influence of different sources of water used for irrigation on the yield of pepper hybrids Cecil F1 and Bianca F1 in the early glasshouse production for the period 1998 - 2000 in the controlled glasshouse conditions in «D.G. – PROMET», Magadenovac, Croatia. Lagoon water and well water were two main sources of water used for irrigation in this experiment. Drip irrigation system was applied for pepper production. In comparison to lagoon water, chemical analyses of well water have shown increased values of the following elements: EC, sodium, potassium, calcium, chlorine, magnesium, bicarbonate, sulphate, iron and boron. Temperature of well water was lower than the allowed minimum and therefore had direct influence on the yield decrease. Consequently, areas which have been irrigated by well water have had problems with accumulation of slime and blocking of sprinklers, disturbed soil structure, fruit deformation and decreased crop yield. Statistical data analysis was conducted by the method of covariation three factorial trial (ABC) with three repetitions for each treatment. The trial showed absolute difference regarding water efficiency of irrigation water from two sources, which has also been statistically determined (P<0,05). Furthermore, statistically justified difference in the average weight of the fruit of each investigated pepper hybrid (P<0,05) has been proven. Codependence of «water for irrigation» (A) and «pepper hybrid» (B), i.e. (AB) is statistically significant as well, and justified at the P<0,05 limit. This means that both pepper hybrids (Cecil F1 i Bianca F1) reacted differently to lagoon water and well water. Factor «year» (C) has not proven to be statistically justified, and therefore does not have any significant influence on the crop yield due to controlled conditions in the glasshouse.