Browsing by Author "Cakmak, I"

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Inheritance of Tolerance To Leaf Iron Deficiency Chlorosis in Tomato
(Springer, 2004) Dasgan, HY; Abak, K; Cakmak, I; Römheld, V; Sensoy, S
By using two tomato genotypes, "227/1" (Fe chlorosis susceptible) and "Roza" (Fe chlorosis tolerant), and their reciprocal F-1, F-2 and BC1 generations, the inheritance of tolerance to leaf Fe deficiency chlorosis of Roza was studied. Plants were grown in a nutrient solution and subjected to 2.0 x 10(-6) M Fe EDDHA and 10 mM NaHCO3 to induce Fe deficiency stress by stabilization of pH to 7.8-8.2. A rating scale of 1-3 for chlorophyll was used and both monogenic and polygenic inheritance hypotheses were tested. Better responses to Fe deficiency, as measured by SPAD meter values, were obtained from the cross "Roza x 227/1" than from the reciprocal cross. Data from F-2 and BC1 suggest Fe chlorosis tolerance of Roza is to be controlled by polygenic loci with a relatively high additive effect.
Phytic Acid and Phosphorus Concentrations in Seeds of Wheat Cultivars Grown With and Without Zinc Fertilization
(Taylor & Francis inc, 2002) Erdal, I; Yilmaz, A; Taban, S; Eker, S; Torun, B; Cakmak, I
Seeds of twenty wheat cultivars grown with (+Zn = 23 kg Zn ha(-1)) and without zinc (Zn) fertilization in a Zn-deficient calcareous soil in Central Anatolia were analyzed for the levels of Zn, phosphorus (P), phytic acid, and phytase activity. Additionally, seeds of four wheat cultivars grown on 55 different locations in Turkey were also analyzed for Zn, P, and phytic acid. In the field experiment with 20 wheat cultivars, seed Zn concentrations showed a range between 7 to 11 mg kg(-1) under Zn-deficient and 14 to 23 mg kg(-1) under Zn-added conditions. Zinc fertilization reduced seed concentrations of P and phytic acid of all cultivars. On average, the reductions caused by Zn fertilization were from 3.9 to 3.5 mg g(-1) for P and from 10.7 to 9.1 mg g(-1) for phytic acid. Irrespective of Zn fertilization, seed phytic acid concentrations showed a large genotypic variation, i.e., from 7 to 12 mg g I with Zn fertilization and 8 to 13 mg g I at nil Zn treatment. As a result of decreases in phytic acid and increases in Zn concentrations by Zn fertilization, phytic acid to Zn molar ratios in seeds of cultivars markedly decreased. On average for ail cultivars, phytic acid to Zn molar ratios decreased from 126 to 56 with Zn fertilization. Seed phytase activity of cultivars was not consistently influenced by varied Zn supply. However, on average for 20 cultivars, Zn fertilization tended to decrease phytase activity. In seeds of four wheat cultivars collected from 55 locations, the concentrations of Zn, P, and phytic acid ranged from 8 to 34 mg kg(-1), 2.1 to 4.9 mg g(-1), and 5.8 to 14.3 mg kg(-1), respectively. Results obtained in the present study indicate that seed Zn concentrations of wheat cultivars grown in different locations of Turkey, especially under Zn-deficient conditions, are very low. Considering very high phytic acid: Zn molar ratios it can be suggested that bioavailability of Zn would be very low for humans.