EFECTELE IRIGĂRII LOCALIZATE ASUPRA CANTITĂŢII ŞI CALITĂŢII PRODUCŢIEI UNOR SOIURI DE CAIS ÎN CONDIŢIILE DIN DOBROGEA EFFECTS OF LOCALIZED IRRIGATION ON FRUIT YIELD AND ITS QUALITY FOR SOME APRICOT VARIETIES UNDER THE CONDITIONS OF DOBROGEA

Dobrogea, with its fertile soils and higher temperatures is one of the most favorable areas for apricot culture in Romania. However, in this area, high production and quality can only be achieved by applying irrigation. The present paper presents the effects of applying four irrigation treatments, i.e. drip irrigation and micro sprinkler, on fruit yield and some indicators regarding fruit quality on both Tudor and NJA 42 varieties. The research was conducted in 2003-2005 on the territory of Research Station for Fruit Growing Constanta, on a calcareous chernozem soil type. On average, when studying NJA 42 tree cultivar, the fruit yield was significantly higher by 32% versus the Tudor cultivar in those three years and five different soil water regimes. Within the two varieties, application of located irrigation through the four treatments determined a significant increase in fruit yield by 32-37%. Fruit yield differences between the two varieties were determined by the different numbers of fruit per tree, and differences in yield between the irrigated and non irrigated variants were determined by the different average fruit mass. On average, on the five different levels of soil water regimes in the case of the Tudor variety higher values of sugar content by 90% and dry matter by 49% versus NJA 42 variety were obtained. On average for the two varieties, in the non irrigated variant the sugar content was higher by 27% and the dry matter by 11% compared to the irrigated variants. For each cubic metre of water applied by the two treatments of drip irrigation, an increase in fruit yield of 11.06 kilograms/m 3 was recorded. In exchange, over the two micro sprinkler irrigation treatments, an increase in fruit yield of 5.18 kilograms/m 3 was obtained. These findings show, primarily, the importance of irrigation on the increase in fruit yield, and secondly, a higher water use efficiency with drip irrigation versus micro sprinkler irrigation.