Effect of the irrigation regime on the productivity of root celery by drip irrigation in the Plovdiv region.

The aim of this study was to determine the influence of irrigation regime on the yield of root celery by drip irrigation. The experience was conducted in the experimental field of Department of Melioration and Land Surveying of Agricultural University, Plovdiv in 2010-2011. The type of the soil is characterized as alluvial-meadow, previous waterlogged. The experiment was carried out in 6 variants: 1) irrigation with 130% of the optimal irrigation application; 2) optimal irrigation /100% of the calculated irrigation application by soil moisture before irrigation up to 80% of field capacity in the depth 0-0,40 m/; 3) irrigation with 70% of the optimal irrigation application; 4) irrigation with 50% of the optimal irrigation application; 5) irrigation with 30% of the optimal irrigation application; 6) without irrigation. Because of the significant differences in the amount of rainfall during the two years, 7 and 14 irrigation applications in 2010 and 2011 were made, respectively. It was found that reducing irrigation rate leads to reduced yields in 3, 4, 5 and 6 variants, but in variant 1 /irrigation with 130% of the optimal irrigation application/ the yield was greater than the optimal irrigation. The productivity of irrigation applications has been calculated for variants and the relationship between the yield and irrigation amount during the growth has been estimated.