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Developing haploid plants by ectopically expressing homologous BABY BOOM (BBM) genes in sorghum (Sorghum bicolor) and soybean (Glycine max)
The constraints in application of conventional techniques in order to develop haploid plants in a reproducible manner, it is of high demand implementing the novel approaches in highly recalcitrant crops. An example to existing novel systems is BABY BOOM (BBM) gene for which the expression from pearl millet or its ectopic expression in egg cell in rice, maize and tobacco has known to promote the haploid induction at very high rates. In this thesis work, native sorghum BBM like genes and soybean GmBBM1 gene were ectopically expressed in egg cell in respective crops under egg cell specific promoter, DD45 cloned from Arabidopsis thaliana to observe the haploid induction responses in these crops. The constructs for three BBM inserts under the control of DD45 promoter were succesfully designed. Haploidy level was checked by flow cytometer and chromosome count by root tip squash method on T 1 plants germinated from T 0 seeds in soybean and the analysis showed that chromosomal aberrations related to haploid cells and aneuploidy were appearent in three transgenic soybean lines, 18-4 (3), 37-4 (Y2) and 46Y2 (3).
Ascorbic acid content evaluation and regulation in strawberry germplasm
Ascorbic acid (vitamin C), as an essential nutrient, is getting increasing attention and strawberries are considered one of its richest natural sources. Current study focused on combined influence of growth conditions, cultivars, and maturity stages on vitamin C content and related characters of fruit chemistry and appearance. Strawberries produced under open field conditions exhibited higher vitamin C content witnessing the role of full sunlight exposure in vitamin C biosynthesis. Protected conditions caused fruits to develop more pigments but accumulated lesser vitamin C. The genotypic influences were significant, showing cultivar Calinda better in organic acids but poor in firmness. Cultivar Sabrina showed highest fruit firmness but at the cost of commercially desired fruit quality characters. Cultivar Sahara performed best for vitamin C and fruit redness, and was high in fruit size, weight, firmness, and organic acids. Two-way and three-way interactions between cultivars, growth conditions, and maturity stages were significant indicating an absolute requisite of studying combined influences in actual field, rather than single factor, controlled, lab experiments. Multiple, large-scale, field studies will shed more light on metabolic regulation of fruit quality. Keywords: Ascorbic acid; Organic acids; Antioxidant; Fragaria; Protected; Environment; Cultivar; Color
Identification of physiological and biochemical traits related to high tuber yielding in potato under drought conditions
Potato is a valuable food crop and number of factors affect its growth, yield and quality including drought stress. So, a study was conducted for the identification of physiological and biochemical traits related to high tuber yielding in potatoes under drought conditions. A Total of 25 potato genotypes, 9 high-yielding, 9 moderate-yielding, and 7 low-yielding under drought and control conditions, were used. Tubers were planted in pots, and during the tuber initiation phase, they were separated into two sets: one as the control group and the other subjected to drought conditions by withholding irrigation for a duration of 12 days. The experiment was conducted two times and data for Biochemical traits, physiological parameters and enzymatic activity of different potato genotypes (high-yielding, moderate-yielding and low-yielding genotypes) under control and drought conditions were determined. The findings revealed that when subjected to drought conditions, all genotypes exhibited an increase in MDA, proline, SOD, POD, and APX levels. The CAT, RWC, Photosynthesis rate, transpiration rate and stomatal conductance and tuber yield were significantly higher under control conditions as compared with drought conditions. The chlorophyll content and leaf temperature were not affected significantly under both normal and drought conditions.
Integrative agronomic and genetic approaches to understand iron and copper deficiency responses in soybean (Glycine max (L.) Merr) and Arabidopsis thaliana
Calcareous-alkaline soil-induced iron (Fe) deficiency chlorosis (IDC) impairs crop growth, yield, and nutritional quality. This thesis investigates agronomic and genetic strategies to enhance the productivity and seed nutrient content of soybean (Glycine max (L.) Merr.) and Arabidopsis thaliana under IDC conditions. IDC-tolerant and sensitive soybean cultivars were analyzed, showing that tolerant cultivars responded better to Fe fertilization, increasing seed Fe concentration, protein content, and size, while reducing seed phytate levels. Genetic analysis identified specific genes within quantitative trait loci (QTL) associated with IDC tolerance, and bioinformatic analysis of Arabidopsis orthologs identified a novel transcription factor, GATA12, involved in iron homeostasis in plant roots. Transcriptomic analysis of IDC-tolerant soybean cultivars showed differential expression of key transcription factors and transporters, including UMAMIT28 from the UMAMIT amino acid transporter family, which plays a crucial role in iron and copper homeostasis. Functional characterization of UMAMIT28 in Arabidopsis confirmed its involvement in maintaining Fe and Cu balance. This thesis highlights the importance of combining agronomic and genetic approaches to enhance crop yield, nutritional quality, and resilience under IDC stress, addressing global food security and malnutrition. Additionally, the discovery of GATA12 and UMAMIT28 advances the understanding of transmetal homeostasis in plants.
Genom boyu ilişkilendirme haritalaması aracılığıyla makarnalık buğdayda su kullanım etkinliği ve kalite özellikleriyle bağlantılı DNA markörlerinin belirlenmesi
Makarnalık buğdayda birden çok genle idare edilen özelliklerin ıslahında geleneksel yöntemler ile moleküler yöntemlerin birlikte kullanılması elzem hale gelmiştir. Bu amaçla geliştirilen son metotlardan olan genom boyu ilişkili haritalama çalışmalarında (GWAS) yüksek genetik çeşitliliğe sahip popülasyon bir kere genotiplenir ve birden fazla özellik için fenotiplenir. Bu çalışmada da 14.255 SilicoDArTve SNP markörüyle genotiplenen 123 makarnalık buğdaydan oluşan popülasyon, 6 farklı çevre koşulunda 3 yıl boyunca arazi denemeleri yürütülerek fenolojik (başaklanma süresi), morfolojik (bitki boyu, bayrak yaprak alanı), fizyolojik, (klorofil indeksi, kanopi sıcaklığı, su kullanım etkinliği, kuraklık hassasiyet indeksi, kuraklık tolerans indeksi), agronomik (bindane ağırlığı) ve kalite (protein oranı, nişasta oranı, yaş gluten oranı, hektolitre ağırlığı, kül içeriği, un rengi, sedimentasyon hacmi) özellikleri için fenotiplenmiştir. GWAS, R'da GAPIT paketinin BLINK modeline göre gerçekleştirilmiştir. Yapılan GWAS sonucunda incelenen özelliklerle ilişkili farklı kromozom bölgelerinde 65 QTL bölgesi belirlenmiştir. Bunlara ilave olarak, kalite odaklı ıslah programları için ebeveyn olabilecek aday makarnalık buğday genotipleri de tanımlanmıştır.
Molecular cloning and bioinformatic analysis of centromeric histone H3 (CenH3) gene in species of onobrychis
In this study, the CenH3 genomic locus of different species of the genus Onobrychis was characterized. The study was carried out by molecular cloning method and the results were analyzed by bioinformatic methods. CenH3 variants of Onobrychis genus were into two main groups, CenH3-α and CenH3-β in silico. CenH3-α group contains 3 different variants, while CenH3-β group contains 2 different variants. The species O. hajastana (2n=2×=14) has the CenH3-α variant and one of the CenH3-β variants, while O. altissima (2n=2×=14 / 2n=4×=28), O. biebersteinii (2n=4×=28), O. oxydanta (2n=2×=14) have the other variant of the CenH3-β group. The results support the findings that the cultivated species O. viciifolia (2n=4×=28) may be allotetraploid and suggest that its ancestors may be O. hajastana and O. oxydanta. There is important defects of genetic studies in the Onobrychis genus. So, this is an original and pioneering study in the Onobrychis genus for phylogenetic analysis and elucidation of the evolutionary process of the centromere.
Comparison of development and physiology of Deschampsia Antarctica ecotype collection grown in two different temperatures
Deschampsia antarctica E. Desv. or Antarctic hairgrass, is a perennial plant belonging to the Poaceae family that grows in terrestrial ecosystems of Antarctica. Antarctic hairgrass, consistently attracts the attention of scientists working in various fields of biology since this species has unique adaptive abilities enabling to survive and reproduce in the extreme climatic conditions of Antarctica. Plants can grow from 0.5 to 25 cm in height. Young shoots are enclosed in a shell, and the leaves are sessile with linear leaf blades. D.antarctica can form clones of the correct shape with a lifespan of up to 35-40 years. Aging and death of old plants are often observed in the central part of the clone, and the cycle of formation of a new clone begins when the plant takes root in a new place (Alberdi and Corcuera, 1991; Lewis Smith, 2003 et al. ,). Temperature is the main factor affecting the rate of plant development. Laboratory studies by Bravo et al. (2001) showed that D.antarctica has a well-developed response to cold acclimatization and that significant cell damage occurs only in plants exposed to temperatures significantly lower than those at which they freeze. Another study by Cortez-Antiquera et al. (2021) with D. antarctica showed that plants grown in vitro are able to tolerate heat shock conditions at 23 and 35°C. The expected increase in temperature due to climate change and the potential for more extreme temperature events will affect plant productivity and several studies have investigated the effect of temperature on plant growth and physiology. Related with that, we aim to compare the effect of two different temperatures (12°C and 22°C) on the growth, physiology and morphology of D. antarctica plants which will be grown in climate chambers to provide a background on the response of this Arctic plant to increasing temperatures and to define the collection that we are preserving in our department.
Determination of morphological, physiological, and agronomical responses of potato genotypes to heat
In the era of global warming, breeding heat-resilient potato varieties is among the most critical goals in potato breeding. This study aimed to evaluate the effect of elevated temperature on the morphological, physiological, biochemical and agronomic characteristics of potato genotypes under field conditions. The field experiments were conducted using a split-plot design with two temperature treatments (ambient and elevated temperature) as main plots and 29 genotypes as sub-plots, each with three replications, in 2022 and 2023. An open-sided polyethylene high tunnel was constructed adjacent to the open field to increase the temperature. This setup raised the ambient temperature by approximately 6–10 °C from planting to harvest, varying depending on the date and time of day. The results indicate elevated temperature effectively promoted potato genotypes' morphological, physiological and antioxidant enzyme activities. Different stress indices were calculated and a cluster analysis was performed to identify high-yielding and tolerant genotypes. Heat-tolerant potato genotypes possess an efficient defence mechanism against reactive oxygen species (ROS) by enhancing the antioxidant enzyme activity under heat stress. This study demonstrates that constructing open-sided clear polyethylene greenhouses to create a warmer environment is an effective strategy for selecting heat-resilient potato genotypes under field conditions.
Tohumluk patates üretiminde farklı irilikteki mini yumrular için dikim sıklığının optimizasyonu
Ön elit kademe tohumluk patates üretiminde farklı irilikteki mini yumrular için tarımsal ve ekonomik açıdan en uygun dikim sıklığının belirlenmesi amacıyla yapılan bu çalışma, 2019 ve 2020 yıllarında Konya ilinde Konya Şeker A.Ş.'nin tohumluk patates üretim alanında (38.26° N 32.40° E) yürütülmüştür. Bölünen Bölünmüş Parseller Deneme Desenine göre üç tekerrürlü olarak kurulan denemelerde Lady Olympia ve Russet Burbank çeşitlerine ait üç farklı irilikteki (<20.0 mm, 20.1-25.0 mm, >25.1 mm) mini yumrular, beş farklı sıra üzeri mesafesinde (10, 14, 18, 22 ve 26 cm) dikilmiştir. Araştırmada uygulamaların morfolojik ve tarımsal özellikler üzerine etkileri incelenmiş, yumru iriliklerine göre dikim sıklığının optimizasyonu için yumru verimi açısından elde edilen verilerin ekonomik analizi yapılmıştır. Her iki yılda da en yüksek verim ve net gelir çeşitlerin büyük (>25.1 mm) yumrularının sırayla 10 cm ve 14 cm sıklıklarla dikilmesi sonucu edilmiştir. En yüksek fayda maliyet oranları (BCR) Lady Olympia çeşidinde büyük (>25.1 mm) yumruların 22 ile 26 cm dikim sıklığından Russet Burbank çeşidinde ise 18 ile 22 cm dikim sıklığından elde edilmiştir. Bu çalışmanın, tohumluk patates üreticileri ve ön elit tohumluk üretimi için faydalı ve uygulanabilir sonuçları vardır.
Developing mutants of negative regulator of immune response gene (CPL-3) in tomato using CRISPR/Cas9
Bacterial infections pose a substantial threat to tomato production, impacting the biochemical and molecular attributes of the crop. This study elucidates the identification and characterization of RNA Polymerase II (RNAP) C-Terminal Domain Phosphatase-like 3 (SlCPL-3) genes in prominent commercial tomato cultivars (Rio-grande, Sazlica, and Falcon). Comprising 11 exons, the SlCPL-3 gene encodes two protein domains, CPDCs, and BRCT. Employing various bioinformatic tools, a predictive 3-D structure and an exploration of phosphorylation potential were conducted. Mutant development in tomatoes allowed an exploration of CPL-3 gene expression under biotic stress, utilizing Pst DC-3000 as the infectious pathogen. Results unveiled the activation of the SlCPL-3 gene during bacterial stress, with upregulated expression observed across various time intervals. Mutant plants exhibited diminished CPL-3 expression compared to wild-type plants, complemented by a subsequent reduction in PR-1 gene expression a marker linked with biotic stress. These findings support the hypothesis that targeting the CPL-3 gene through CRISPR/Cas9 holds promise for enhancing crop resilience against bacterial pathogens.