In a field experiment, the effect of foliar Zn applications on the concentration of Zn in seeds of a bread wheat cultivar (Triticum aestivum L. cv. Balatilla) was studied during different stages of seed development. In addition, a staining method using dithizone (DTZ: diphenyl thiocarbazone) was applied to (1) study the localization of Zn in seeds, (2) follow the remobilization of Zn during germination, and (3) develop a rapid visual Zn screening method for seed and flour samples. In all seed development stages, foliar Zn treatments were effective in increasing seed Zn concentration. The highest Zn concentration in the seeds was found in the first stage of seed development (around the early milk stage); after this, seed Zn concentration gradually decreased until maturity. When reacting with Zn, DTZ forms a red-colored complex. The DTZ staining of seed samples revealed that Zn is predominantly located in the embryo and aleurone parts of the seeds. After 36 h of germination, the coleoptile and roots that emerged from seeds showed very intensive red color formation and had Zn concentrations up to 200 mg kg ÿ1 , indicating a substantial remobilization of Zn from seed pools into the developing roots (radicle) and coleoptile. The DTZ staining method seems to be useful in ranking flour samples for their Zn concentrations. There was a close relationship between the seed Zn concentrations and spectral absorbance of the methanol extracts of the flour samples stained with DTZ. The results suggest that (1) accumulation of Zn in seeds is particularly high during early seed development, (2) Zn is concentrated in the embryo and aleurone parts, and (3) the DTZ staining method can be used as a rapid, semiquantitative method to estimate Zn concentrations of flour and seed samples and to screen genotypes for their Zn concentrations in seeds.

Membrane thermostability (MT) is used widely to measure high‐temperature tolerance of wheat (Triticum aestivum L.). However, the method, which measures conductivity of electrolytes released from injured cells, is affected by environmental factors for growing plants and is not effective on maturing plants. Amino acids exosmose like inorganic electrolytes from cells that are damaged by high temperature but, unlike electrolytes, typically occur only in living cells. These studies determined whether measuring leakage of amino acids effectively assessed high‐temperature injury to wheat in comparison with the conductivity method, and if it was suitable for evaluating maturing plants. Membrane thermostability was measured by conductivity and ninhydrin methods on seedlings and maturing plants grown under controlled conditions and on 12 genotypes at two field locations. Relative injury (RI) values from hardened seedlings differed significantly among 12 genotypes. Rankings of the genotypes were similar for both methods in seedlings (r = 0.94), and values of both methods were significantly correlated in maturing plants (r = 0.90). The RI values by the ninhydrin method but not the conductivity method differed significantly among the 12 genotypes and identified the top‐yielding cultivars at both field locations, but results of neither method correlated with grain yields. The results showed that the ninhydrin method measures high‐temperature injury of young plants as successfully as the conductivity method, but neither method is suitable for maturing plants.

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yılları arasında Geçit Kuşağı Tarımsal Araştırma Enstitüsü ve Selçuk Üniversitesi iş birliğinde TÜBİTAK tarafından desteklenen araştırma sonuçlarına göre, sulu koşullarda Bezostaya1 ekmeklik buğday çeşidiyle, erken dönem azot uygulaması (ekim + kardeşlenme) 0, 4, 8 ve 12 kg N da -1 , başaklanma zamanında ise yaprak solüsyonu (üre formunda) olarak 0, 2, 4 ve 6 kg N da -1 seviyeleri karşılaştırılmıştır. Araştırmada, geleneksel azotlu gübre uygulama zamanında (ekim + kardeşlenme) uygulanan değişik azot seviyeleri başaklanma zamanında bayrak yaprak klorofil kapsamları (SPAD) ve bayrak yaprak toplam azot kapsamları (TN) açısından bir varyasyon yaratılmıştır. Çalışmanın sonuçlarına göre, başaklanma zamanında yapraktan uygulanan azotun tane protein kapsamında en az %1 artış sağlayacağı NSPAD kritik eşik değerleri, Bezostaya1 için 0,95 olarak bulunmuştur. TN için bulunan kritik eşik değerleri ise, Bezostaya1 için %4,31 olmuştur. Her bir kg da -1 N miktarının tane protein kapsamında sağladığı artış, Bezostaya1 için, erken kullanımda %0,18, geç kullanımda %0,30 olmuştur. Ayrıca, protein ve ilgili kalite unsurları üzerine hem erken, hem de geç azot kullanımı etkili olmakla birlikte, başaklanma döneminde yapraktan solüsyon olarak uygulamanın daha etkili olduğu belirlenmiştir. Bu özelliklerden, tane protein kapsamı ile SDS sedimentasyon (r=0,93**), Uzama kabiliyeti (r=0,96**), uzayabilirlik (r=0,96*), hamur gelişme süresi (r=0,87**), tolerans değeri (r=0,56**) ve enerji değeri (r=0,89**) parametreler arasında istatistiki olarak önemli düzeyde korelasyon vermiştir. The Effects of Foliar Nitrogen Treatments at Heading Stage on Grain Protein Contents of Bread Wheat Cultivars in in Irrigated Condition A R T I C L E I N F O A B S T R A C T Research ArticleReceived 19 In this study, with using bread wheat cultivars (Bezostaya1) in irrigated condition, it was compared that 0, 4, 8 and 12 kg N da -1 in the early period nitrogen application, both planting and tillering stage and 0, 2, 4 and 6 kg N da -1 solution form using (Urea form) in heading stage. In this study, through with different nitrogen rates in traditional nitrogen application time a variation was created in terms of SPAD and TN at heading stage. According to results of the study, in irrigated conditions, it was found that application of nitrogen from leaves in heading stage can increase the protein content at least 1 % and the critical threshold value of NSPAD was 0.95 for Bezostaya1, on the other hand the critical threshold value of TN critical was % 4.31 for Bezostaya1 in same condition. The using of every 1 kg da -1 of N was increased 0.18 % in early application and 0.30 % in late application for Bezostaja1 in grain protein content. Although both early and late applications was effective for protein content and related quality compounds, the application of leaf solution in heading stage was more dominant. From these properties, it has provided a significant high correlation in the level of protein content with SDS sedimentation(r=0.93**), elongation ability(r=0.96*...

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