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WOS: 000390736100012 PubMed ID: 27619947 Effects of gamma radiation on physiological responses of the M-1 sainfoin plants were investigated. Seeds of sainfoin ecotype 'Kocas' were exposed to 0, 400, 500 and 600 Gy from a Co-60 source at a dose rate of 0.483 kGy h(-1). Irradiated and unirradiated seeds were sown into culture vessels containing MS-basal medium to be cultured for 30 days under in vitro conditions. At the end of this period, seedlings, which germinated from the radiated and unirradiated seeds, were transferred into pots in a growth chamber for 30 days more. Chlorophyll contents, activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), as well as contents of monodehydroascorbate reductase (MDA) and proline were examined in unirradiated and irradiated 60-day-old seedlings. Overall, the activities of the antioxidant enzymes (SOD, CAT and GR) and contents of chlorophyll and proline in the leaves tended to increase after irradiation in a dose dependent manner. By contrast, the activity of APX decreased. The lipid peroxidation characterized by the MDA content remained unchanged, except after irradiation to 500 Gy. The highest CAT activity and the highest praline content were observed after irradiation to the highest dose of 600 Gy. The highest SOD and GR activities were observed after irradiation to the lowest tested dose of 400 Gy. This is the first study that provided basic information on the impact of gamma radiation on physiological responses of sainfoin and its radiosensitivity. These findings will be useful in development of a mutation breeding program of sainfoin.

Immature and mature embryos of 12 common winter wheat (Triticum aestivum) genotypes were cultured in vitro to develop an efficient method of callus formation and plant regeneration from mature embryo culture, and to compare the responses of both embryo cultures. Fifteen days after anthesis, immature embryos were aseptically dissected from seeds and placed with the scutellum upwards on a solid agar medium containing the inorganic components of Murashige and Skoog (MS) and 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). Mature embryos were moved slightly in the imbibed seeds. The seeds with moved embryos were placed furrow downwards in dishes containing 8 mg/l 2,4-D for callus induction. The developed calli and regenerated plants were maintained on 2,4-D-free MS medium. Plants regenerated from both embryo cultures were vernalized and grown to maturity in soil. Regenerated plantlets all maintained the hexaploid chromosome number. A strong genotypic effect on the culture responses was found for both explant cultures. Callus induction rate, regeneration capacity of callus and number of plants regenerated were independent of each other. Mature embryos had a high frequency of callus induction and regeneration capacity, and therefore, being available throughout the year, can be used as an effective explant source in wheat tissue culture.

WOS: 000431531600015 This study was conducted to evaluate the effect of different NaCl concentrations (0, 100 and 150 mM) on the morphological and biochemical parameters of different sainfoin ecotypes 'Kocas', 'Malya,' 'Altinova' and 'Ulas' under controlled conditions. The morphological parameters included seed germination, seedling and root lengths, and seedling fresh and dry weights while the biochemical parameters included chlorophyll and proline contents, lipid peroxidation (MDA), and the activities of antioxidant enzymes (SOD, CAT, APX, and GR). The results demonstrated that increase in NaCl concentration caused an overall decrease in morphological parameters and an increase in the biochemical parameters in all ecotypes. The findings showed that among all ecotypes, 'Kocas' had higher chlorophyll and proline content, increased activity of CAT, GR, and APX, and increased fresh and dry weight in response to salt stress. To the best of our knowledge, this is the first report on the evaluation of enzymatic and non-enzymatic defense systems in sainfoin plants under salt stress. Turkish Scientific and Technical Research Council (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113Z399] This research is part of the 113Z399 project financially supported by the Turkish Scientific and Technical Research Council (TUBITAK). We express our sincerest gratitude to them for their support. This study was part of a Ph.D. thesis of Ramazan BEYAZ.

Bu araştırma, İtalyan çimi çeşitlerinin yemkalitesini yükseltmede önemli bir potansiyeli olan azotlu gübrelerin değişikdozlarının etkilerini belirlemek üzere yapılmıştır. Orta Anadolu bölgesi kıraçkoşullarında, 2008 ve 2009 yıllarında yürütülmüştür. Ankara Üniversitesi ZiraatFakültesi Tarla Bitkileri Bölümü deneme tarlasında tesadüf bloklarında bölünmüşparseller deneme desenine göre 3 tekrarlamalı olarak kurulmuştur. Çalışmada azotlugübre olarak amonyum nitrat (% 33 N) gübresinin 0, 4, 8, 12, 16, 20 ve 24kg da-1 dozları ve İtalyan çimi çeşidi olarak da Gemini, Tetraflorumile Lolita kullanılmıştır. Erken ilkbaharda 30 cm sıra arası verilerek ekilenparsellerde gerektiği dönemlerde elle yabancı ot mücadelesi yapılmıştır.Parsellerdeki bitkiler çiçeklenme-başaklanma dönemine geldiğinde gözlemler vehasat yapılmıştır. Çalışmadan elde edilen sonuçlara göre; İtalyan çimi çeşitleriarasında incelenen özelliklerden protein verimi, protein oranı, ham kül oranı,asitte çözünmeyen lif (ADF), nötr deterjanda çözünmeyen lif (NDF) ve nispi yemdeğeri (NYD) bakımından önemli farklılıklar belirlenmiştir. Azotlu gübredozları protein oranı, protein verimi, ADF, NDF ve NYD üzerine etkili olmuştur.Ankara ve benzer koşullarında yapılacakİtalyan çimi yetiştiriciliğinde yüksek verim ve kaliteli yem elde etmek içinLolita çeşidine 8 kg da-1 azot dozu uygulanması tavsiye edilebilir., This research was conducted to determine the effects of different doses of nitrogen fertilizers which have a potential to increase the forage quality of Italian rye grass cultivars. It was carried out at the experimental area of Field Crops Department of Agricultural Faculty of Ankara University between the years of 2008 and 2009. The experiment was designed in split blocks with three replicates in the experimental plots of Field Crops Department of Agricultural Faculty of Ankara University. Nitrogen in ammonium nitrate (33% N) form was applied on main blocks with the amount of 0, 4, 8, 12, 16, 20 and 24 kg da-1 doses. Italian ryegrass cultivars Gemini, Tetraflorum and Lolita were places in sub-plots. Hand seeding was performed in early spring on the rows which was 30 cm apart each other. Weeds were taken out on the plots manually whenever needed. When the plants were at flowering stage, observations were made and plants were harvested for hay. According to the results; statistical differences were found among Italian rye grass cultivars for crude protein rate, protein yield, crude ash rate, acid detergent fiber (ADF), neutral detergent fiber (NDF) and relative feeding value (RFV). Nitrogen fertilizer doses affected crude protein rate, protein yield, crude ash rate, ADF, NDF and RFV. In order to get higher quality forage in the Italian ryegrass cultivation in Ankara and similar conditions, Lolita cultivar and 8 kg da-1 nitrogen fertilizer is recommended according to results of this research.

The expression of insecticidal genes must be induced at appropriate time and in sufficient amount to confer protection against targeted pests. However, the increased scientific reports of resistance development in insect pest against insecticidal delta-endotoxins, produced by Bacillus thuringiensis, provide impetus for the development of alternative insect management strategies. The present study was conducted to investigate the importance of targeted expression of a hybrid insecticidal gene (SN19) in potatoes. For this purpose, two plant expression vectors were constructed by cloning hybrid SN19 gene (cry1Ba-domain I–III and cry1Ia-domain II) under the control of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1) and CaMV 35S promoter, and were transferred to Agrobacterium tumefaciens strain EHA 105. Four potato genotypes (Marabel, Innovator, Tokat 10/1 and Tokat 6/24) were transformed with EHA 105 strain harboring pTF101.1 35S–SN19 and pTF101.1 AoPR1–SN19 constructs. Phosphinothricin (PPT) was used at concentration of 1 mg/l for selection of primary transformants. PCR results showed the presence of both introduced SN19 and bar genes in 43 plants out of total 154 putative transgenics. Expression of SN19 protein in primary transformants was confirmed by Western blot assays. The mechanical wounding of transgenic plants exhibited more accumulated levels of SN19 proteins during post wounding period. Leaf biotoxicity assays with Colorado potato beetle (Coleoptera) and tomato leafminer (Lepidoptera) exhibited 100% mortality of the pests in primary transformants. Based on our mortality results with both constructs, we concluded that the potato transgenic lines exhibited targeted expression of insecticidal gene under the control of AoPR1 promoter upon insect wounding with eliminated toxicity of Cry protein and hence can be further used effectively in potato breeding programme. © 2017, Korean Society for Plant Biotechnology and Springer Japan KK. 111T816 Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÜBITAK Genetic Engineering and Biotechnology Institute, Scientific and Technological Research Council of Turkey, Gebze, Kocaeli, Turkey Funding The research project was supported by a Grant from Scientific and Technological Research Council of Turkey (TÜBİTAK) Project # 111T816.

Bu arastirma, Italyan cimi cesitlerinin verimi ve kalitesini yukseltmede onemli bir potansiyeli olan azotlu gubrelerin degisik dozlarinin etkilerini belirlemek uzere yapilmistir. Orta Anadolu bolgesi kirac kosullarinda, 2008-2009 yillarinda yurutulmustur. Ankara Universitesi Ziraat Fakultesi Tarla Bitkileri Bolumu deneme tarlasinda tesaduf bloklarinda bolunmus parseller deneme desenine gore 3 tekrarlamali olarak kurulan calismada, azotlu gubre olarak amonyum nitrat (%33) gubresinin 0, 4, 8, 12, 16, 20 ve 24 kg/da dozlari ve Gemini, Tetraflorum ile Lolita Italyan cimi cesitleri kullanilmistir. Erken ilkbaharda 30 cm sira arasi verilerek ekilen parsellerde gerektigi donemlerde elle yabanci ot mucadelesi yapilmistir. Parsellerdeki bitkiler ciceklenme-basaklanma donemine geldiginde gozlemler ve hasat yapilmistir. Calismadan elde edilen sonuclara gore; Italyan cimi cesitleri arasinda incelenen ozelliklerden bitki boyu ve yesil ot verimi bakimindan onemli farkliliklar belirlenmistir. Azotlu gubre dozlari bitki boyu, sap kalinligi, yesil ve kuru ot verimi uzerine etkili olmustur. Calismanin yurutuldugu her iki yilda, bitki boyu, sap kalinligi, yesil ve kuru ot verimi arasinda farklilik bulunmustur. Ankara kosullarinda yapilacak Italyan cimi yetistiriciliginde yuksek verim ve kaliteli yem elde etmek icin 8 kg/da azot dozu kullanilmasi tavsiye edilebilir.

In this study, karyotype analysis of the species of Onobrychis sp. was undertaken using the squash method. The results showed that the chromosome number of Onobrychis tournefortii (Willd.) Desv., O. gracilis Besser, O. hypargyrea Boiss. is 2n = 14 and O. argyrea Boiss. subsp. argyrea Boiss., 2n = 16. The karyotype formula of O. tournefortii (Willd.) Desv. is 4m+3sm, of O. hypargyrea Boiss. and O. gracilis Besser 3m+4sm, and of O. argyrea Boiss. subsp. argyrea Boiss. 2m+ 5sm+1 st.

Erysiphe trifolii and Leveillula taurica on Onobrychis spp. in Turkey, are described and illustrated.

WOS: 000389669800002, Plant lectins have become efficient sources of insect resistance in crops. The present study was conducted to identify, amplify, clone and characterize the plant lectin gene GNA. The lectin, present in Galanthus nivalis (snowdrop), is an agglutinin toxic to hemiptera. The attempt was made to elucidate the relationship of the lectin gene trGNA (GNA isolated and characterized from Turkey) with other previously cloned lectins having insecticidal activity and to ensure the presence of the conserved mannose-binding region/site in the gene sequence. The full-length cDNA of trGNA was 477 bp that contained a 333 bp open reading frame encoding 157 amino acid proteins with 23 amino acids of signal peptide. BLAST results showed that trGNA has 89-97% similarity with previously reported GNA sequences while it has 84-96% similarity with earlier reported GNA protein sequences. No intron was detected within the region of genomic sequence corresponding to trGNA full-length cDNA. According to the search results from the NCBI (National Centrer for Biotechnology Information database), trGNA from Galanthus nivalis is most similar to the previously reported lectin sequences of Narcissus tazetta with a similarity percentage of 87%. The obtained results are useful for engineering of plants with enhanced insecticidal activity against chewing and sucking insects, causing crop pests. In addition, medical application of lectins may also be considered., Scientific and Technological Research Council of Turkey (TUBITAK) - BIDEB [2215], The authors are grateful to The Scientific and Technological Research Council of Turkey (TUBITAK) - BIDEB for granting PhD. fellowship (2215) to Mr. S.D. Khabbazi.

WOS: 000389771500008, In order to address biosafety concerns regarding the constitutive expression of foreign genes in crops, we applied a strategy aimed at confining foreign gene expression in insect wounding sites of cotton. For this purpose, a plant expression construct was designed by cloning the AoPR1 promoter (pathogenesis-related protein gene isolated from Asparagus officinalis) upstream from the insecticidal gene cry1Ac. The Turkish cotton cultivar cv. STN-468 was transformed using the Agrobacterium tumefaciens strain LBA4404 containing the recombinant binary vector pRD400 harboring cry1Ac under a wound-inducible promoter. The neomycin phosphotransferase (nptII) gene was used as a selectable marker at a concentration of 100 mg/L. The primary transformants were analyzed for T-DNA integration and expression using standard molecular approaches. The efficacy of insecticidal gene control of the AoPR1 promoter was investigated using leaf bioassays with 2nd instar larvae of Helicoverpa armigera and Spodoptera littoralis. Positive primary transformants from T-0 progeny were further raised under greenhouse conditions to obtain progeny (T-1). The introduced gene was properly inherited and expressed in T-1 progeny. The mechanical wounding of plants resulted in increased cry1Ac protein levels during 0-48 h of the wounding period. The transgenic lines exhibited appreciable levels of resistance against targeted insect pests in the leaf bioassays. The use of a wound-inducible promoter to drive insecticidal gene expression is a valuable insect resistant management strategy as gene expression will remain limited to the insect biting sites of plant and crop, food and environmental concerns can be minimized., TUBITAK (The Scientific and Technological Research Council of Turkey) [2216], The corresponding author is grateful to TUBITAK (The Scientific and Technological Research Council of Turkey) for providing postdoctoral fellowship Code: 2216) to carry out the research activities at University of Ankara. The authors acknowledge Dr. Umut Toprak, Associate Professor, Department of Plant Protection, Faculty of Agriculture, University of Ankara for providing Helicoverpa armigera for our lab bioassays experiment

Phylogenetic relationships were studied based on morphology and nuclear ribosomal DNA internal transcript spacer (nrDNA ITS) sequences in 49 populations of 36 Onobrychis taxa belonging to 5 sections (Dendobrychis, Lophobrychis, Onobrychis, Heliobrychis and Hymenobrychis) naturally grown in Turkey. The morphological data (46 quantitative characters) were standardized and submitted for PCA analysis before the performance of hierarchical clustering analysis. In addition, a 577-bp region of the nrDNA ITS sequences was compared to generate a dendrogram using the neighbor-joining method. According to the obtained results, the Onobrychis genus is clearly divided into the Onobrychis and Sisyrosema subgenera both molecularly and morphologically; however, in terms of molecular data, while the Onobrychis subgenus showed polyphyletic features, the Sisyrosema subgenus had monophyletic features. Additionally, long-wing taxa belonging to Dendobrychis and Onobrychis and O. crista-galli belonging to Lophobrychis located in the same clade in Onobrychis showed polyphyletic features. This finding was confirmed in terms of long-wing taxa as well as morphology and indicated that these three sections were entangled with each other under the Onobrychis subgenus.

WOS:000378689600017, t: The present study addressed the successful in vitro seed germination, bulblet regeneration, increased bulblet size, hardening, and acclimatization of Persian lily (Fritillaria persica). Seed germination rate was recorded as 86.7% and 96.7% after 2 and 3 months of cold treatment at 4 °C, respectively. Bulblet explants taken from a germination experiment were cultured on Murashige and Skoog (MS) medium supplemented with 0.5–2.0 mg/L thidiazuron (TDZ). Maximum bulblet regeneration frequency and bulblets per explants were achieved on a medium containing 2.0 mg/L TDZ. Leaf disc and leaf scale explants isolated from germinated seedlings were also cultured on MS medium containing 2–6 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) with a constant concentration of 0.2 mg/L kinetin. Both explants yielded the highest bulblet regeneration on MS medium containing 2 mg/L 2,4-D and 0.2 mg/L kinetin. A combination of 1.5 g/L agar and 1.6 g/L GELRITE resulted in a maximum bulblet diameter with a higher number of roots. The addition of 10 g/L NaCl to the culture medium resulted in the best root and leaf formation and secondary bulblet regeneration. Exposure of regenerated bulblets to 10 g/L NaCl at 4 °C for 2 months on a medium with 20 g/L sucrose was also found to be beneficial for acclimatization.

WOS: 000373886900005, Most of the commercialized Bt crops express cry genes under 35S promoter that induces strong gene expression in all plant parts. However, targeted foreign gene expression in plants is esteemed more important as public may be likely to accept 'less intrusive' expression of transgene. We developed plant expression constructs harboring cry1Ac gene under control of wound-inducible promoter (AoPR1) to confine Bt gene expression in insect wounding parts of the plants in comparison with cry1Ac gene under the control of 35S promoter. The constructs were used to transform four Turkish cotton cultivars (GSN-12, STN-468, Ozbek-100 and Ayhan-107) through Agrobacterium tumefaciens strains GV2260 containing binary vectors p35SAcBAR.101 and AoPR1AcBAR.101 harboring cry1Ac gene under control of 35S and AoPR1, respectively. Phosphinothricin (PPT) was used at concentration of 5 mg L-1 for selection of primary transformants. The primary transformants were analyzed for transgene presence and expression standard molecular techniques. The transformants exhibited appreciable mortality rates against larvae of Spodoptera exigua and S. littoralis. It was found that mechanical wounding of T (1) transgenic plants was effective in inducing expression of cry1Ac protein as accumulated levels of cry1Ac protein increased during post-wounding period. We conclude that use of wound-inducible promoter to drive insecticidal gene(s) can be regarded as a valuable insect-resistant management strategy since the promoter activity is limited to insect biting sites of plant. There is no Bt toxin accumulation in unwounded plant organs, seed and crop residues, cotton products and by-products, thus minimizing food and environmental concerns., Scientific and Technological Research Council of Turkey TUBITAK [111O254], The work on development of transgenic cotton in our laboratory is being supported by grants from Scientific and Technological Research Council of Turkey TUBITAK (Project No. 111O254). The authors acknowledge contribution and support of TUBITAK. The authors are also thankful to Leicester University (UK) for giving permission to use AoPR1 promoter for research purposes.

Effects of gamma radiation on physiological responses of the M

Sternbergia fischeriana is an endangered geophyte and therefore in vitro micropropagation of this plant will have great importance for germplasm conservation and commercial production. Bulb scale and immature embryo explants of S. fischeriana were cultured on different nutrient media supplemented with various concentrations of plant growth regulators. Immature embryos produced higher number of bulblets than bulb scales. Large numbers of bulblets were regenerated (over 80 bulblets/explants) from immature embryos on Murashige and Skoog (MS) medium supplemented with 4 mg l−1 6-benzylaminopurine (BA) and 0.25 mg l−1α-naphthaleneacetic (NAA) or 2 mg l−12,4-dichlorophenoxyacetic acid (2,4-D) after 14 months of culture initiation. Regenerated bulblets were kept at 5 °C for 5 weeks and then transplanted to a potting mixture.

Tobacco leaf disc explants were inoculated with Agrobacterum tumefaciens strain GV2260 carrying p35S GUS-INT to determine the influence of different co-cultivation temperatures (18 – 26 °C), periods (24 – 96 h) and media (solid and liquid) on transformation efficiency. Kanamycin-resistant shoots developed on leaf discs inoculated with Agrobacterium after 4 weeks of culture initiation. Regenerated shoots were excised and rooted in the basal medium supplemented with 100 mg dm −3 kanamycin and 250 mg dm −3 augmentin. The rooted plantlets were finally transferred to compost and confirmed by GUS assay and PCR analysis. The highest transformation frequency was achieved from the explants co-cultivated with A. tumefaciens in liquid medium for 48 h at 22 or 24 °C.

It was found that in vitro microtuberization of potato (Solanum tuberosum L.) was affected considerably by temperature and gelling agent. The best results were obtained in cultures maintained at 20–22° C in dark. Moreover, considerable increases in number, average weight and yield of microtubers was obtained on media solidified with gelrite compared to agar, when used as gelling agent. Number of microtuber formation and their weight had significant positive relationship (r = 0.630 and r = 0.771 respectively) with microtuber yield per plantlet.

The pollen size and morphology of 20 Onobrychis Adans. taxa from Turkey were studied using both light and scanning electron microscopy. Of the taxa studied, Onobrychis fallax Freyn & Sint. and Onobrychis elata Boiss. & Balansa showed the smallest size of pollen grains, while the largest were found in Onobrychis aequidentata (Sibth. & Sm.) d'Urv. and Onobrychis viciifolia Scop. The pollens of all taxa studied represent the tricolpate type of pollen and are prolate in shape. The type of exine found in the studied taxa is reticulate (sect. Dendobrychis DC. and sect. Laphobrychis Hand.-Mazz.), suprareticulate (sect. Onobrychis), or microreticulate (sect. Hymenobrychis DC. and sect. Heliobrychis Bunge). A correlation is observed between the pollen size and chromosome number.

The genotoxic potential of the commercial herbicide Illoxan (containing 284 g/L, diclofop-methyl) was determined by using chromosome aberrations in Allium cepa root tip cells. The EC(50) value was determined as 150.00 mg/L using a root growth inhibition test and then the roots were treated with 37.50, 75.00, and 150.00 mg/L concentrations for 12, 24, and 48 h. The results indicated that Illoxan significantly increased the abnormal cell frequency at all concentrations and treatment periods when compared with their controls, and this increase was close-dependent for the 24 and 48 h treatments. On the other hand, Illoxan significantly decreased the mitotic index (MI) in all treatments when compared with their controls. The decrease in the mitotic index was slightly close-dependent for the 24 and 48 h treatments. Illoxan did not affect the percentage of mitotic stages. For the pretreated root tips, Illoxan (except 37.50 mg/L, at 12 and 24 h) significantly increased the frequency of abnormal cells in a dose-dependent manner. This study indicates that Illoxan decreased the mitotic index and produced clastogenic and aneugenic types of abnormalities in Allium cepa root tip cells. The data obtained in this study showed that plant bioassays call be used as ail important test battery to detect possible genotoxicity of chemicals.

Efficient and reproducible shoot regeneration has been established from immature cotyledons and embryo axes of Hungarian vetch. Immature embryo axes showed higher regeneration capacity than immature cotyledons in most media tested. Immature cotyledons appeared to produce the highest frequency of shoot regeneration on 20 μM 6-benzylaminopurine (BA) and 2.5 μM α-naphthaleneacetic acid (NAA)-containing medium; whereas, shoot regeneration on immature embryo axes was best achieved on a medium supplemented with 5 μM each of BA and NAA. Regenerated shoots were excised and rooted in half-strength MS medium supplemented with 5 μM indole-3-butyric acid (IBA). Rooted plantlets were acclimatized to ambient conditions and later established under greenhouse conditions.

A procedure is described for the rapid and efficient adventitious shoot regeneration from leaflets, petioles and stems of field-grown sainfoin plants. All explants formed shoots on a range of media supplemented with 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA). Stem explants appeared to have better regeneration capacity than leaflet and petiole explants in most media tested. The highest frequency of shoot regeneration was achieved from stem segments on a medium containing 20 μM BA and 0.5 μM NAA. Regenerated shoots rooted in half-strength Murashige and Skoog medium containing 5 μM indole-3-butyric acid and later established well under greenhouse conditions.

An efficient in vitro bulblet production procedure from immature zygotic embryos of endemic and endangered Muscari muscarimi Medik. was described in the current study. Zygotic embryos were first isolated from immature seeds and cultured on different nutrient media compositions supplemented with various combinations of ?-naphthalene acetic acid (NAA), picloram, dicamba, 6-benzylaminopurine (BAP), and thidiazuron (TDZ). The best bulblet regeneration (59 bulblets per explant) was achieved in Murashige and Skoog (MS) medium containing 4 mg/L BAP and 0.5 mg/L NAA after 1 year of culture initiation. Regenerated bulblets were then transferred into MS medium without plant growth regulators for rooting. Bulblets produced well-developed root systems and increased their size on this medium after 2 months. All rooted bulblets were successfully transplanted into a potting mixture and acclimatized to ambient conditions. © TÜBİTAK.

Seven genotypes of winter durum wheat (Triticum durum Desf.) were cultured to establish an efficient method of callus formation and plant regeneration from mature embryo culture, and to compare the responses of immature and mature embryo cultures. Immature embryos were aseptically dissected from seeds and placed, with the scutellum upwards, in dishes containing Murashige and Skoog's (MS) mineral salts and 2mg 2,4- dichlorophenoxyacetic acid (2,4-D) per litre. Calli and regenerated plants were maintained on 2,4-D-free medium. Mature embryos were moved slightly on the imbibed seeds. For callus formation, the seeds with moved embryos were placed, furrow downwards, in dishes containing 8 mg 2,4-D per litre. The developed calli and regenerated plants were maintained on the MS medium. Plants regenerated from both embryo cultures were vernalized and grown to maturity in soil. Variability was observed among the wheat genotypes tested for various culture responses in both explant cultures. Callus induction rate and regeneration capacity of callus were independent of each other. Mature embryos have a low frequency of callus induction but a high regeneration capacity. Considering availability, rapidity and reliability, this form of mature embryo culture can be used as an alternative method for immature embryo culture.

Immature cotyledons and embryo axes of sainfoin were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of 6-benzylaminopurine (BAP) and a-naphthaleneacetic acid (NAA) to induce adventitious shoot regeneration. The highest frequency of shoot regeneration occurred following an initial callus growth on a MS medium containing 0.5 mg/l BAP and 2 mg/l NAA. Immature embryo axes showed higher regeneration capacity than immature cotyledons, however, shoot elongation was best achieved on immature cotyledons. Regenerated shoots were excised and rooted in half strength MS medium with 1 mg/l indole-butyric acid (IBA) or 1 mg/l NAA. The rooted plantlets were finally transferred to compost.

Transformation of fenugreek ( Trigonella foenumgraecum) was carried out with A281 oncogenic strain of Agrobacterium tumefaciens using root, cotyledon and hypocotyl explants excised from 1-week-old seedlings, which showed that the plant was highly susceptible to transformation. Tumors ( calli) were selected on 50 mg dm(-3) kanamycin. They were analyzed for beta-glucuronidase (GUS) expression. Presence of uidA (gus) gene, was confirmed by polymerase chain reaction (PCR) amplification.

Efficient and reproducible shoot regeneration has been established from immature zygotic embryos of lesser burnet on MS medium containing 4 μM BAP and 10 μM NAA. Regenerated shoots were best rooted in half-strength MS medium supplemented with 10 μM NAA and later established in the greenhouse.

The present investigation was carried out to study the cytological effects of the herbicide racer “flurochloridone” (3-chloro-4-(chloromethyl)-1-[3-(trifluoromethyl)= phenyl]-2-pyrrolidinone) on Allium cepa with respect to the cell response, mitotic index, mitotic abnormalities and chromosome aberrations. The roots of bulbs were treated with the following concentrations depending on the root growth inhibition test: 80 ppm (LD50), 40 ppm (LD50/2) and 20 ppm (LD50/4). The results indicated that flurochloridone herbicide reduced the mitotic division in A. cepa as compared to their control groups. The reduction in mitotic activity was more significant when the concentration of the herbicide increased and the exposure time was prolonged. The treatment conducted with flurochloridone induced a significant percentage of abnormal mitosis. Seven types of abnormalities were recorded: C-metaphase, laggards, stickiness, bridges, fragments, multipolarity and poliploidy. Micronucleated cells were also observed at interphase. In additon, in pretreated root tips, chromosome breaks, fragments and sister union were detected. © 2003 Taylor & Francis Group, LLC.