Sancar Fatih Özcan

Influence of different co-cultivation temperatures, periods and media on Agrobacterium tumefaciens-mediated gene transfer

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.

Adventitious Shoot Regeneration and Micropropagation in Calendula officinalis L.

Hypocotyl, cotyledon and cotyledonary node explants of Calendula officinalis L were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of thidiazuron (TDZ), kinetin (KIN), α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) to induce adventitious shoot regeneration and micropropagation. The highest frequency of adventitious shoot regeneration was achieved from hypocotyl and cotyledon explants on MS media supplemented with 0.75 mg dm−3 TDZ and either 0.25 or 0.50 mg dm−3 IBA. Efficient in vitro clonal propagation was also induced from cotyledonary nodes on a range of media supplemented with 0.75 mg dm−3 TDZ and 0.05 mg dm−3 NAA or 2 mg dm−3 KIN and 1 mg dm−3 NAA. Regenerated shoots were excised and rooted in MS medium supplemented with 1 mg dm−3 NAA. The rooted plantlets were finally transferred to pots.

High Frequency Shoot Regeneration from Cotyledonary Node Explants of Different Lentil (Lens Culinaris Medik) Genotypes and In Vitro Micrografting

ABSTRACT Shoot regeneration capacities of 21 different lentil genotypes were tested on MS medium containing 0.225 μM thidazuron (TDZ) using cotyledonary node explants. It was observed that 0.225 μM TDZ contributed positively in multiple shoot regeneration from cotyledonary node based calli. The highest frequency of shoot regeneration (20.6 shoots/explants) was achieved from Ahn 362 genotype. Regenerated shoots were excised and cultured in MS medium supplemented with 1.25 μM IBA for rooting. However, root formation was not achieved on most of the regenerated shoots. To overcome this problem, regenerated shoots of seven most promising genotypes were micrografted on 3–4 days old root stocks of cultivar Kayi 91 succesfully. Micrografted plantlets were acclimatized to ambient conditions and later established under greenhouse conditions.

In vitro crown galls induced by Agrobacterium tumefaciens strain A281 (pTiBo542) in Trigonella foenum-graecum

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 β-glucuronidase (GUS) expression. Presence of uidA (gus) gene, was confirmed by polymerase chain reaction (PCR) amplification.

In Vitro Plant Regeneration from Turkish Grasspea (Lathyrus Sativus L.) Using Immature Zygotic Embryo Explant

ABSTRACT Grasspea (Lathyrus sativus L.) is an important grain legume crop cultivated in many countries of the world as animal feed. There is need to improve the plant through various available techniques. The study is aimed to develop an efficient and reproducible protocol for in vitro rapid and large-scale propagation of the plant from immature zygotic embryos using various concentrations of Thidiazuron (TDZ) and 6 benzylaminopurine (BAP)- α Naphthalene acetic acid (NAA) with and without ascorbic acid. The results showed that both TDZ and BAP-NAA without ascorbic acid were ineffective to induce shoot regeneration from explants due to excretion of phenolic compounds. The TDZ (with ascorbic acid) was more potent for axillary shoot regeneration compared to BAP-NAA (with ascorbic acid) with the highest shoot regeneration on MS medium containing 0.45 mg/l TDZ. The shoots regenerated on MS medium containing 0.45 mg/l TDZ (with ascorbic acid) were rooted on MS medium supplemented with 0.30, 0.60, 0.90 and 1.20 mg/l NAA. The best rooting was achieved on MS medium containing 0.90 mg/l NAA. It was not difficult to acclimatize all of the rooted plants in soil in greenhouse.

An insight into cotton genetic engineering (Gossypium hirsutum L.): current endeavors and prospects

Cotton (Gossypium hirsutum L.) is the most significant cash crop and backbone of global textile industry. The importance of cotton can hardly be over emphasized in the economy of cotton-growing countries as cotton and cotton products contribute significantly to the foreign exchange earnings. Cotton breeders have continuously sought to improve cotton’s quality through conventional breeding in the past centuries; however, due to limited availability of germplasm with resistant to particular insects, pests and diseases, further advancements in cotton breeding have been challenging. The progress in transformation systems in cotton paved the way for the genetic improvement by enabling the researchers to transfer specific genes among the species and to incorporate them in cotton genome. With the development of first genetically engineered cotton plant in 1987, several characteristics such as biotic (insects, viruses, bacteria and fungi) resistance, abiotic (drought, chilling, heat, salt), herbicide tolerance, manipulation of oil and fiber traits have been reported to date. Genetic engineering has emerged as a necessary tool in cotton breeding programs, strengthening classical strategies to improve yield and yield contributing factors. The current review highlights the advances and endeavors in cotton genetic engineering achieved by researchers worldwide utilizing modern biotechnological approaches. Future prospects of the transgenic cotton are also discussed.

In Vitro Induction of Crown Galls by Agrobacterium Tumefaciens Super Virulent Strain A281 (pTiBo 542) in Salvia Sclarea and S. Pratense

ABSTRACT Salvia sclareae and S. pratense are important medicinal plants. The application of genetic engineering to these important crops should allow incorporation of some traits like insect and herbicide resistance. Co-cultivation experiments with A281 strain of Agrobacterium tumefaciens using leaf explants excised from 35 days old seedlings of both species showed that these were highly susceptible to transformation. Moreover, the strain A281 resulted in development of shooty tumors in S. sclarea and rooty tumors in S. pratense, which were selected on MS medium containing 50 mg/1 kanamycin. All of them were GUS positive.