Effects of cold stratification pretreatment and pH level on germination of Centaurea tchihatcheffii Fisch. et Mey. seeds

Centaurea tchihatcheffii Fisch. Et. Mey. is a critically endangered (CR) plant species due to destruction of habitat, strong anthropogenic pressure, biotic and abiotic factors. It grows in limited areas in Gölbai district of Ankara, Turkey and in the world. It is very necessary to conserve it and prevent its extinction. Previous studies emphasise that low germination rate of its seed is primarily due to deep seed dormancy. Therefore, studies was done on C. tchihatcheffii seeds, to investigate the effects of cold stratification for different periods (90, 120 and 150 days) and different pH values (pH 6.5, 7.5 and 8.5) on seed germination. The highest germination percentage (58.89 ± 6.39%) was observed in seeds stratified for 150 days at all pH values of growing media, followed by seeds stratified for 120 days (42.78 ± 4.57%). An increase in pH level had negative effects on seed  germination, the lowest germination (27.22 ± 4.18 %) was determined at pH 8.5.Key words: Centaure tchihatcheffii, critically endangered, seed  germination, stratification, pH values

Effects of different planting dates on improving yield of Fritillaria imperialis L. and Fritillaria persica L. bulbs damaged by small narcissus fly (Eumerus strigatus Fallen)

Fritillaria imperialis and F. persica were planted during April 2003 and May 2004 growing seasons on the basis of split block design with three replications to investigate the effects of planting dates on various plant parameters and extent of recovery by planting 25% damaged bulbs. The results showed significant effects of planting dates on plant height, number of bulbs per plant and infected bulb ratio. A comparison of the two species showed that F. persica gave more bulblets than F. imperialis. A generalcomparison of the two species also showed that damaged bulbs of F. imperialis produced lesser yield compared to F. persica. Furthermore, both species gave more number of bulblets from early and mid September plantings compared to early and mid October plantings. The most suitable date of planting was determined as September 1st and 15th

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Somatic embryogenesis in white clover (Trifolium repens L.)

I White Clover (Trifolium repens L.) is an important perennial forage legume widely cultivated in Turkey and many other countries. It also helps in improving soil structure by fixing atmospheric nitrogen, and prevents soil erosion. The application of modern tissue culture techniques to this important plant should contribute to improvement in terms of production. Hypocotyls, epicotyl and cotyledon explants of a local ecotype of white clover were treated with various concentrations of Thidiazuron (TDZ) + Naphthalene acetic acid (NAA) and kinetin + NAA in MS medium to establish an efficient in vitro somatic embryogenesis system. High frequency of embryogenesis was observed on the MS medium containing 9.29 mM kinetin + 1.07 mM NAA (14.35embryos per explant) or 0.34 mM TDZ + 0.54 mM NAA (29.62 embryos per explant). It was concluded that embryogenesis was significantly influenced by the added plant growth regulators in the concentration-dependent manner;: Plantlets from the embryos were recovered on the MS medium and were transferred to a greenhouse, where they flowered and set fertile seeds

Adaptation of eight American blackberry (Rubus fructicosus L.) cultivars for Central Anatolia

Blackberry is an important fruit plant cultivated for its delicious fruit throughout Europe and America. Although the fruit has wide acceptance in Turkey, it is not cultivated on large scale. The study aimed toevaluate the performance of Arapaho, Black Satin, Cherokee, Chester Thornless, Dirksen Thornless, Jumbo, Navaho and Loch Ness cultivars of American origin for adaptation under Central Anatolian conditions at Ankara during 2002 - 06. The results showed that changes in the environmental conditions affected yield, performance of number of canes, cane length, cane diameter, yield per plant, fruit weight and total acid content (g/l) significantly. Overall comparison of the results showed that cv. Chester Thornless is most suitable for the environmental conditions of Central Anatolia

Abiotic factors affecting in vitro pollen grain germination in sainfoin (Onobrychis viciifolia Scop.)

A reliable in vitro method for germination of sainfoin pollen grains has been developed. Highest pollen germination rate of 96% with mean pollen tube length of 223.5 mum was obtained on medium containing of 100 g/l sucrose, 200 mg/l KNO3, 150 mg/l H3BO3, 150 mg/l MgSO4, 150 mg/l Ca(NO3)(2), 175 g/l PEG 4000 and stigma extract at pH 6.5

In vitro regeneration of Turkish dwarf chickling (Lathyrus cicera L) using immature zygotic embryo explant

Dwarf chickling (Lathyrus cicera L) is an important forage legume crop. However, due to the presence of neurotoxin amino acid (b-N-oxalyl-L-a,b-diaminopropionic acid) in the dwarf chickling, its cultivationis limited. There is need to carry out studies for the development of varieties with reduced or none ofthis neurotoxin for beneficial and prolong consumption by animals. The study reports tissue cultureapproaches for multiplication of the plant using thidiazuron (TDZ), 6-benzylaminopurine (BAP), and #8733-naphthalene acetic acid (NAA) from immature zygotic embryos of the plant. The highest number (16.25)of shoots per explant was recorded on MS medium supplemented with 0.45 mg/l TDZ and 0.4 mg/lascorbic acid. Much reduced shoot regeneration was recorded on MS medium containing different combinations BAP+NAA+ascorbic acid. The TDZ-regenerated shoots were rooted by pulse treatmentwith 50 mg/l IBA for 7 min. The plantlets were successfully acclimatized under the greenhouse conditions

In vitro plant regeneration from Turkish Narbon Vetch (Vicia narbonensis L. var. narbonensis L.)

Narbon vetch (Vicia narbonensis L.) is an important forage species among vetches of central Europe, Mediterranean, Near East, Ethiopia, central Asia and India. The study reports in vitro micropropagation of narbon vetch using cotyledon node, shoot tip and zygotic embryo explants on MS medium containing 0.25, 0.50, 0.75 and 1.00 mg/l BAP. The highest number of 4.42 shoots was recorded on cotyledon node explants, which was followed by significantly reduced number of 3.40 and 3.54 shoots per explant on shoot tip and zygotic embryo with two cotyledons, respectively. Zygotic embryo with two cotyledons explant was recalcitrant and slow in regeneration compared to other explants but any concentration of BAP was sufficient for multiple shoot regeneration. Shoot length decreased statistically with increase in each concentration of BAP in the regeneration medium. 65.0% shoots rooted on MS medium containing 0.5 mg/l IBA and newly regenerated plants were acclimatized in the greenhouse

In vitro plant regeneration from Narbon Vetch (Vicia narbonensis L.) using cotyledonary node explants

Narbon vetch (Vicia narbonensis L.) is an agriculturally important forage plant that widely grows in an area extending from Central Europe to various parts of Asia. The study reports axillary shootregeneration from cotyledonary node explants obtained from, in vitro raised seeds of 4 - 5 and 14 - 15 days old seedlings on MS medium containing 2 - 6 mg/l kinetin-0.1 mg/l indole-3-butyric acid (IBA). Noshoot regeneration was recorded on 14 - 15 days old cotyledon node explants. Whereas, 4 - 5 days old cotyledon node explants showed high regeneration potential with the highest number of 3.85 shootsper explant, with mean shoot length of 2.11 cm and shoot regeneration frequency of 93.33%. The shoots obtained from all regeneration media could be easily rooted after pulse treatment with 50 mg/l IBA for 7min. All of which were morphologically normal and fertile and easily established under greenhouse conditions

Use of psyllium (isubgol) husk as an alternative gelling agent for the culture of prokaryotic microalgae (Cyanobacteria) Chroococcus limneticus Lemmermann and eukaryotic green microalgae (Chlorophyta) Scenedesmus quadricauda (Turpin) Brebisson

Agar is popularly used as gelling agent to obtain in vitro culture of prokaryotic and eukaryotic microalgae. Exclusive use of agar is resulting in over exploitation of its resources and makes itessential to look for alternative and cheap sources. The study reports in vitro culture of prokaryotic microalgae (Cyanobacteria) Chroococcus limneticus and eukaryotic green microalgae (Chlorophyta)Scenedesmus quadricauda on BG11 medium solidified with 15 g L-1 agar or 10, 15, 20, 25, 30, 35 and 40 g L-1 psyllium (isubgol) husk as gelling agent. The results demonstrated that prokaryotic microalgae C.limneticus was less appropriate for culture on psyllium husk gel compared to eukaryotic green microalgae S. quadricauda. However, the cells of C. limneticus could be multiplied on 10 or 15 g L-1psyllium husk as gelling agent. The highest number of 642000 cells mL-1 of C. limneticus on 15 g L-1 psyllium husk were far lower than 722000 cells mL-1 on agar gelled medium (control). Contrarily, thecells of S. quadricauda could be multiplied on all concentrations of psyllium husk. Compared to the highest number of 546000 cells mL-1 of S. quadricauda on 15 g L-1 agar (control), the highest number of538000 cells mL-1 was recorded on 15 g L-1 psyllium husk gel. The results indicated very similar and comparable cell multiplication behavior of S. quadricauda on agar or 15 g L-1 psyllium husk anddemonstrate the advantage of the very cheap alternative gelling agent psyllium husk over expensive agar for possible use in analytic experiments pertaining to eukaryotic green microalgae