A study evaluating the effects of iodine treatment on the hatching success of turbot eggs was carried out. A hundred, 500, 1500 and 3000 ppm iodine treatment were performed for 10 minutes. The treatment with 3000 ppm iodine presented lower hatching percentage (70.0 ±6.08%). The control group (97.6 ±1.42%) and disinfected with 100 ppm iodine (91.3 ±4.04%) resulted in slightly higher hatching percentage, and significantly different from the other disinfected groups (P < 0.05). The control group and disinfected eggs with 1500 and 3000 ppm iodine were statistically significant in abnormality (P < 0.05). Zero-day-old eggs, 1-day-old eggs and 3-day-old eggs were treated with a dose of 100 ppm iodine for ten minutes. Differences in abnormalities between 0-day-old eggs (early morula stage) and 1 and 3 day-old eggs were statistically significant (P < 0.05). In conclusion, 100 ppm iodine appeared suitable for disinfecting turbot eggs if treatment is applied at the early morula stage.

Sexual dimorphism in growth of the Black Sea turbot (n=119), Psetta maxima, was studied in a long-lasting (12 months) growth experiment at ambient temperature. The in fluence of onset of puberty and subsequent maturation on growth was evaluated. There were no initial size differences, but the final weight of females was larger than that of males (P < 0.05). Signi ficant growth differences between sexes were detected at the age of 30 months post hatch (P < 0.05). Maturing females had the highest growth rate and reached the largest size (1454.0 ±369.99 g in 30 months), whereas male body weights leveled off around 1187.6±248.87 g. This growth advantage substantiates the need to develop techniques for the production of all-female juveniles in the hatchery. Özet: Karadeniz Kalkanında (Psetta maxima) Cinsiyet Farklılığının Büyüme Üzerine EtkisiKaradeniz kalkanında (Psetta maxima) (n=119) cinsiyet farklılığının büyüme üzerine etkisi doğal su sıcaklığında 12 ay süren büyütme denemesi ile çalışıldı. Balıkların olgunlaşmasının büyüme üzerine etkileri değerlendirildi. Başlangıçta boy ve ağırlık yönünden farklılıklar yoktur fakat dişi balıkların son ağırlıkları erkek balıklardan daha fazladır (P<0,05). Otuz aylık balıklarda cinsiyetler arasında önemli büyüme farklılığı bulunmuştur (P<0,05). Olgunlaşmakta olan dişi balıklar en yüksek büyüme oranı ile 30 ayda 1454.0 ±369.99 g ağırlığa ulaşmış iken erkek balıkların ağırlığı 1187.6±248.87 g da kalmıştır. Dişilerin büyüme avantajları tüm dişi yavru üretimine olan ihtiyacı ortay koymaktadır.