This paper presents a study of water consumption in apple tree in the conditions of Timisoara, between 2000 and 2010, and of water deficit during apple tree vegetation period.  Well knowing water requirements of a fruit tree species is of importance in determining irrigation requirements if we wish to obtain large high-quality productions. Literature shows that water requirements vary depending on the different biological, meteorological, soil, and technological factors. This explains largely the different results mentioned in literature concerning annual, monthly and daily water requirements in apple tree in different geographical areas. The theme has direct applicability in practice, particularly for the farmers. Research was carried out on the fruit tree plantation of the Didactic Station of the Banat University of Agricultural Science and Veterinary Medicine of Timisoara, Romania, within a trial organised in an intensive apple tree plantation. The apple tree cultivar we studied, Jonathan, is precocious, very productive, and moderately pretentious as far as climate and soil are concerned, resistant to apple scab, codling moth or apple root aphid. The soil is a cambic chernozem, poorly gleyed, with low salinisation and alkalinisation below 100 cm, meso lime, on fine medium loessoid deposits, medium loamy clay. The value of hydrophysic indices show that the soil has a high capacity of retaining water since it has a natural fertility favourable to apple tree and is suitable for drip irrigation. The studied area is within the moderate temperate continental climate area, with a mean multiannual temperature of 10.8 0 C and atmospheric precipitations reaching a mean multiannual value of 631.0 mm. Water consumption was calculated with the Thornthwaite formula, the most suited taking into account that it best correlates with research field results. Thus, we calculated monthly, daily total and mean water consumption during the vegetation period (April 1 – October 1) for all the studied years between 2000 and 2010, and then we compared these consumption levels with the coverage degree from precipitations during the same period of time, obtaining hydric deficits, i.e. the necessity of covering them through irrigation.  The highest hydric deficits were in 2000 and 2009 (447.12 mm and 355.76 mm, respectively), but there has been hydric deficit that coincided with maximum consumption periods in apple tree (June, July and August).We also need to supplement these hydric deficits through drip irrigation, the method with the lowest water consumption, compared to classical irrigation methods. water requirement, apple tree, hydric deficit

water requirement, apple tree, hydric deficit

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