Mansur Hakan Erol

Ovary culture is among the most effective techniques for haploid induction in horticultural crops, including cucumber. The application of doubled haploid technology can significantly accelerate cultivar development by enabling the rapid production of homozygous inbred lines. This study evaluated the effects of culture medium combinations of plant growth hormones (2,4-D, NAA, IAA, IBA, PUT, BAP, KIN, TDZ) on haploid induction in cucumber via ovary culture. Four induction and five regeneration media were tested across four cucumber varieties: Beith Alpha, PTK40, Botanik, and Sardes. The highest embryo formation rate (88%) was observed in the Botanik variety, followed by Sardes, PTK40, and Beith Alpha, particularly on induction medium supplemented with 2,4-D and PUT. Plant regeneration was achieved on a medium containing IAA and BAP. Flow cytometric analysis of twenty randomly selected plants confirmed that all were diploid, with no haploids detected. This outcome indicates that the primary objective of inducing haploid plants was not successfully accomplished. These findings highlight substantial limitations in the current induction protocol and underscore the need for further optimization to improve haploid recovery efficiency. The authors recommend more research to develop and improve ploidy level stability for cucumber ovary culture.

This study aimed to evaluate the morphological responses of three tobacco genotypes Birlik 124, Birlik 128, and İzmir Özbaş to Polyethylene glycol (PEG) mediated in vitro drought stress using a multivariate approach. PEG concentrations of 0% - 2% - 4% and 6% were applied to simulate osmotic stress, and five morphological parameters; plant height, leaf number, multiplication rate, fresh weight, and dry weight were assessed. Principal Component Analysis was additionally performed to evaluate genotype-level variation across treatments. PEG concentration and genotype significantly affected all traits, with genotype × PEG interaction being significant for leaf number and dry weight. Multiplication rate and plant height declined progressively with increasing PEG levels, while İzmir Özbaş consistently maintained superior values, indicating enhanced drought tolerance. Leaf number was highest in İzmir Özbaş (42.9) and lowest in Birlik 124 under 4% PEG (20.1), reflecting genotype-specific stress sensitivity. Multiplication rate decreased across all genotypes under stress, yet İzmir Özbaş retained higher rates under 4% and 6% PEG, suggesting resilience in shoot proliferation. Fresh weight showed a genotype-dependent decline, with Birlik 124 exhibiting gradual reduction and İzmir Özbaş displaying partial recovery at 6% PEG. Remarkably, dry weight increased with PEG concentration, particularly in Birlik 124, which reached 0.53 g at 6% PEG the highest among all genotype × PEG combinations highlighting a compensatory biomass accumulation mechanism under stress. Principal Component Analysis (PCA) revealed distinct genotype clustering across PEG levels, with the first two components explaining 79.7% of the total variance. İzmir Özbaş and Birlik 128 showed broader dispersion, indicating morphological plasticity, while Birlik 124 remained tightly clustered, suggesting a stable growth strategy. Overall, the findings demonstrate that PEG-induced osmotic stress elicits genotype-specific morphological responses, İzmir Özbaş exhibiting complementary drought adaptation traits. These results provide valuable insights for genotype screening and in vitro drought tolerance assessment in tobacco.

Drought stress significantly affects the yield and quality of agricultural crops. Plants have developed various adaptations to cope with drought stress. These adaptations involve the regulation of physiological and biochemical mechanisms regulated by many genes. Therefore, identification of cultivars with strong responses to drought stress will provide important contributions to breeding programs. In this study, Hayward and Matua kiwifruit cultivars were used and the plants were subjected to drought in vitro in nutrient media containing PEG 6000 (Polyethyleneglycol) at concentrations of 0, 1, 2, and 3%. The morphological parameters of the plants were examined during the culture period and WRKY TF was utilized to determine the molecular regulations induced by drought stress in plants. For this purpose, the expression levels of WRKY3, WRKY9, WRKY21, WRKY28, WRKY41, WRKY47, WRKY65 and WRKY71 genes were analyzed in leaf and root tissues of the cultivars. The findings showed that the plants in the 2% and 3% PEG media were significantly affected by drought stress, with a notably low root formation performance. The gene expression analysis revealed that the expression levels of genes in the leaf and root tissues of plants under drought conditions were higher compared to the control group. The data obtained from the analyses indicated that the Hayward and Matua cultivars exhibited strong responses to drought both morphologically and genetically.

Almond is one of the economically important nut species for Türkiye. There are many genotypes adapted to different regions of Türkiye. The propagation of these genotypes through plant tissue culture methods is essential. Among nut species, almonds are classified as recalcitrant plants that respond poorly to plant tissue culture techniques. In this study, the development of eight genotypes obtained through selection was examined under in vitro conditions in full and ½ NRM media containing different concentrations of IBA (0, 1, 2 mg/L). As a result of the study, the longest plant height was observed in genotype 48-6 (2.04 cm), while the highest number of leaves was obtained in genotype 33-B-44 (12.26 leaves). Rooting was observed in genotype 33-B-54, which was selected from Mut, Mersin, in a ½ NRM rooting medium supplemented with 2 mg/L IBA. The results are considered significant since these genotypes have been selected for the first time.

In this study, the solid culture method, and Plantform™ and SETIS™ temporary immersion bioreactor systems were used comparatively to propagate, root, and acclimatize ‘Grande Naine’ and ‘Azman’ banana varieties for rapid, cheap, and mass production in in vitro conditions. Micropropagation rate, plant height, number of leaves, and fresh and dry weight parameters were investigated in the micropropagation stage across eight subcultures. Rooting rate, plant height, number of leaves, number of roots/plant, root length, fresh and dry weight parameters were investigated in the rooting stage. Photosynthetic pigment analyses and stoma examinations were performed throughout all stages. In the micropropagation stage, a 20% increase in the Plantform™ system, a 12% increase in the SETIS™ system in ‘Grande Naine’, an 82% increase in the Plantform™ system, and a 98% increase in SETIS™ system in ‘Azman’ were determined compared to the solid culture. At the rooting stage, higher data were obtained from bioreactor systems than solid culture. Plants from bioreactor systems acclimatized faster and developed healthier in the greenhouse stage. It was determined that stomata were more active, and pigment accumulation was higher in bioreactor systems. Genetic variations across subcultures are among the most critical issues in banana clonal propagation. Leaf samples were taken from each system, and plant variation was investigated using SSR (Simple Sequence Repeat) markers. No variation was observed from the initial stage to the greenhouse stage. As a result, it has been determined that bioreactor systems are an essential alternative for the mass production of bananas.

Bu araştırmada farklı tütün çeşitlerinde çimlenme performansı üzerine farklı ışıklanma sürelerinin etkileri araştırılmıştır. Araştırmada Ege bölgesi tütünlerinden Akhisar 97, İzmir Özbaş, Birlik 124 ve Birlik 128 olmak üzere 4 çeşit test edilmiştir. Tütün tohumları in vitro koşullarda 24 saat aydınlık, 16 saat aydınlık ve 24 saat karanlık koşullarında tutulmuştur. Çimlenme hızı, çimlenme gücü ve ortalama çimlenme süresi parametreleri incelenmiştir. Araştırma sonuçlara göre, en yüksek çimlenme hızı 24 saat aydınlık uygulamasında %81.6 ile Akhisar 97 çeşidinde, en düşük oran ise 24 saat karanlık uygulamasında %0 ile Birlik 124 çeşidinde elde edilmiştir. Çimlenme gücü parametresinde en yüksek oran 24 saat aydınlık uygulamasında %88.8 ile Birlik 128 çeşidinde, en düşük oran ise 24 saat karanlık uygulamasında Özbaş çeşidinde %51.2 olarak gerçekleşmiştir. Ortalama çimlenme süresi açısından 24 saat aydınlık uygulamasında 5.2 gün ile Akhisar 97 çeşidinde en kısa ve 24 saat karanlık uygulamasında 11.7 gün ile Birlik 124çeşidinde en uzun çimlenme süreleri elde edilmiştir. Genel olarak 24 saat aydınlık uygulamasında tüm çeşitlerde daha iyi sonuçlar alınmıştır.

The study of crop genetic diversity has received attention in recent decades to develop new varieties adapted to harsh environmental conditions. Pea (Pisum sativum L.) is one of the main sources of legumes due to its higher protein content. In the present investigation, 25 accessions of Turkish and Tunisian peas were characterized by fifteen ISSR markers in order to preserve this germplasm and develop new highperformance varieties. Means of diversity indices, Polymorphism information content (PIC), resolving power, marker index, major allele frequency and Shannon index were 0.70, 5.56, 3.20, 0.89 and 0.35, respectively. The analysis revealed a higher polymorphism (84.15%). The coefficient of similarity Jaccard varied from 0.45 to 1 exhibiting a greater genetic variety. The patterns detected by the cluster analysis, divided the 25 pea genotypes into three main groups. These findings were in agreement with the population structure which divided accessions into three main populations. Therefore, this paper has clearly shown the usefulness of the ISSR markers to provide a great degree of polymorphism for peas. The information collected from this work can help pea breeders to implement a selection program that improves the distribution of this crop in Turkey and in the arid regions of Southern Tunisia.