Mean Number Of Shoots Research Articles

Adventitious shoot induction from cultured internodal explants of Malaxis acuminata D. Don, a valuable terrestrial medicinal orchid

Malaxis acuminata is a terrestrial orchid that grows in shady areas of semi-evergreen to shrubby forests. It is highly valued for its medicinal properties as dried pseudo-bulbs are important ingredients of several Ayurvedic preparations. In this study, adventitious shoot buds were induced from internodal explants of M. acuminata grown on Murashige and Skoog (MS) medium supplemented with different concentrations of 6-benzyladenine (BA), kinetin (Kn), and thidiazuron (TDZ). Of the three cytokinins used, TDZ at 3 mg l−1 induced the highest frequency (82%) of organogenic explants. However, all responding explants produced only a single adventitious shoot irrespective of the type and concentration of the cytokinin. Adding 0.5 mg l−1 α naphthaleneacetic acid (NAA) to the medium enhanced adventitious shoot formation. In the presence of 3 mg l−1 TDZ and 0.5 mg l−1 NAA, frequency of organogenesis was 96% with a mean number of 6.1 shoots per explant. Prolonged culture or subculture on the same medium did not promote further shoot production. However, transfer of these cultures to MS medium supplemented with 3 mg l−1 TDZ and 0.5 mg l−1 NAA and various concentrations of different polyamines (PAs), including spermine, spermidine, and putrescine, significantly increased mean shoot number per explant. The highest frequency of shoot induction (100%) and mean shoot number per explant (14.6) was observed on MS medium with 3 mg l−1 TDZ, 0.5 mg l−1 NAA, and 0.4 mM spermidine. Regenerated shoots were excised and subcultured on an elongation medium consisting of MS medium with 3 mg l−1 BA. Moreover, the highest frequency of rooting (96%) and mean number of roots per shoot (3.3) was observed on MS medium with 4 mg l−1 indole-3-butyric acid (IBA) and 1.5 mg l−1 activated charcoal (AC). Almost 90% of rooted shoots were successfully acclimatized and established ex vitro.

Morphological variation in Tricyrtis hirta plants regenerated from heavy ion beam-irradiated embryogenic calluses

In order to induce horticulturally valuable mutants in the Liliaceous ornamental Tricyrtis hirta, embryogenic calluses of this species were irradiated with 12C+6 ion beams. Morphological characterization was performed on 35, 37 and 15 plants regenerated from calluses irradiated with 5, 10 and 20 Gy ion beams, respectively, and on 10 plants from non-irradiated calluses after 3 years of cultivation in pots. No plants were regenerated from calluses irradiated with 50 Gy ion beams. There were no large differences in the mean values of leaf length, leaf width, soil and plant analyzer development (SPAD) value of leaves, flower length and flower diameter between the control (division-derived plants from the mother plant of the embryogenic calluses) and the irradiation treatments at different doses. On the other hand, the mean number of shoots per plant increased, and the mean shoot length and the mean number of nodes per shoot decreased in the irradiation treatments. The mean number of flowers per plant was increased in the 20 Gy irradiation treatment. For most morphological characteristics investigated, the variation spectrum widened with increase in the irradiation dose. Several horticulturally attractive variations such as dwarfism, slender and deep green leaves, and large flowers were observed in regenerants from the irradiation treatments, and these variations were stable after additional 2 years of cultivation in pots or garden. Thus mutation induction by heavy ion beam irradiation of embryogenic calluses is a valuable tool for improving horticultural value of T. hirta.

Large-scale in vitro propagation of Impatiens repens Moon., a critically endangered medicinal plant in Sri Lanka

SummaryImpatiens repens Moon. (Ceylon Balsam: Family Balsaminaceae) is an endemic, critically endangered, medicinal plant in Sri Lanka. Habitat destruction and over-exploitation have resulted in the virtual extinction of this species. To grow this plant sustainably, a micropropagation protocol was developed using nodal explants for rapid, large-scale propagation. Nodal segments were established on Murashige and Skoog (MS) medium supplemented with different combinations of 6-benzylaminopurine (BAP) and Kinetin for shoot induction. Shoots were established on MS medium supplemented with different combinations of BAP and indole-3-acetic acid (IAA) for shoot multiplication. Micro-shoots were established on full-strength or half-strength MS medium supplemented with different concentrations of α-naphthalene-acetic acid (NAA) for root induction. MS medium supplemented with 2.0 mg l–1 BAP and 1.0 mg l–1 Kinetin gave the highest mean number of shoots per nodal explant (4.7), the highest mean shoot length (3.2 cm), and the highest frequency of shoot regeneration (100%). Addition of a combination of BAP and IAA significantly influenced shoot multiplication. The highest mean number of shoots per shoot explant (18.8) was observed on MS basal medium supplemented with 2.0 mg l–1 BAP and 0.1 mg l–1 IAA. The highest mean number of roots per shoot, mean root length, and frequency of rooting were observed on half-strength MS medium supplemented with 1.0 mg l–1 NAA. Plantlets were acclimatised, with a 96% survival rate, on a 3:1 (v/v) mix of sand: compost (leaf mould).

Gelling agents and culture vessels affect in vitro multiplication of banana plantlets

Agar is the most commonly used gelling agent in media for plant tissue culture. Because of the high price of tissue-culture-grade agar, attempts have been made to identify suitable alternatives. The type of culture vessel and lid also affects the gaseous composition inside the vessel as well as light penetration. In turn, the vessel affects growth parameters, such as shoot elongation, proliferation and fresh weight, as well as hyperhydric degradation processes. We examined the effects of different culture vessels, including commercial glass jars, magenta boxes, and disposable containers, as well as different gelling agents (agar-agar, Agargel, Phytagel, and plant agar) on the micropropagation of Dwarf Cavendish bananas in an effort to find a combination that yields large numbers of high-quality seedlings. The different culture vessels did not significantly affect seedling culture success. The medium significantly affected shoot weight. Phytagel resulted in the highest shoot weight (overall mean = 2.4 g), while agar, Agargel and plant agar resulted in 1.7, 2.2 and 2.2 g, respectively. Disposable container/Phytagel and Magenta/Agargel combinations yielded the highest shoot weights (2.9 and 3.0 g, respectively). Mean shoot length increased progressively with subculture (four subcultures were made). The highest mean shoot length was obtained with Phytagel and Agargel media (6.4 and 6.3 cm, respectively). Shoot number was significantly affected by medium only at subculture 4. Overall, the highest mean shoot length was obtained with the Magenta/Agargel combination (8.5 cm). Phytagel and plant agar gave higher mean shoot number than agar and Agargel (2.1, 2.1 and 1.7 and 1.9, respectively). The costs of the media and of the culture vessels need to be taken into account for final choice of the banana shoot culture system.

Comparison of in vitro regeneration pathways in Punica granatum L.

When cotyledonary explants, excised from in vitro germinated seedlings, of pomegranate (Punica granatum L.) were incubated on solid Murashige and Skoog (1962) medium supplemented with 21 μM naptheleneacetic acid (NAA) and 9 μM 6-benzyladenine (BA), 80% of explants developed callus. A high frequency of shoot organogensis was obtained when explants were incubated on MS medium supplemented with 8 μM BA, 6 μM NAA, and 6 μM giberrellic acid (GA3). However, adding 24 μM silver nitrate (AgNO3) to this medium markedly enhanced shoot regeneration frequency (63%) and mean number of shoots per explant (11.26) and length of shoots (2.22 cm). Highest frequency of in vitro rooting, mean number of roots/shoot (4.32), and mean root length (2.71 cm) were obtained when regenerated shoots were transferred to half-strength MS medium supplemented with 0.02% activated charcoal. Well-rooted plantlets were acclimatized, and then transferred to soil medium. Moreover, when zygotic embryos of P. granatum, excised from seeds collected at 16 weeks following full bloom, were incubated on MS medium containing 30 g l−1 sucrose, 15% coconut water, 21 μM NAA, and 9 μM BA, they developed the highest frequency of embryogenic callus, clumps with globular embryos, and mean number of both globular and heart-shaped embryos per callus clump. Subjecting zygotic embryo explants to six-week dark incubation period was essential for embryogenic callus induction, and these were subsequently transferred to 16 h photoperiod for further growth and development of somatic embryos. Germination of somatic embryos was observed when these were transferred to MS medium was supplemented with 60 g l−1 sucrose.

In vitro Shoot Regeneration of Citrullus vulgaris Schrad (Watermelon)

In this study, shoot regeneration using cotyledons derived from seedlings of diploid and triploid yellow watermelon (cultivars Hwang Fong Yellow Queen, Round Dragon and Chin San Seedless) was investigated. Multiple shoots from auxiliary meristems were obtained without adventitious shoot. Shoot regeneration system for watermelon was successfully established from cotyledon sections of 4 to 5 day-old in vitro seedling. The explants were collected from the proximal cotyledon with hypocotyls segment. Highest mean number of multiple shoots were obtained (9.83±0.54) for cultivar Hwang Fong Yellow Queen on MS medium supplemented with 20 µM BAP as compared to (8.87±0.81) for Chin San Seedless on 5 µM of BAP and (6.00±0.32) for Round Dragon on 10 µM of BAP. From these results, cultivar Hwang Fong Yellow Queen was used for further experiment due to its highest percentage of germination and mean number of shoots. Subsequently, the cultivar successfully rooted (80%) on half strength MS medium supplemented with 0.5 µM IAA. Finally, 50% of these rooting plantlets were acclimatized on soil.

Thidiazuron: an efficient plant growth regulator for enhancing Agrobacterium-mediated transformation in Petunia hybrida

Efficient shoot regeneration and Agrobacterium-mediated genetic transformation systems were developed for Petunia hybrida cv. Mitchell. Leaf explants of petunia were cultured on Murashige and Skoog (MS) medium with different concentrations of thidiazuron (TDZ) without auxin. The highest frequency of shoot regeneration (52.1%) and mean number of shoots per explant (4.1) were obtained on medium containing 2 mg l−1 TDZ. Leaf explants inoculated with Agrobacterium tumefaciens strain EHA101/pIG121Hm harboring s-glucuronidase (uidA) and hygromycin resistance genes developed putative transformant shoots. The highest frequency of shoot regeneration (22.5%) and mean number of transformant shoots per explant (2.4) were obtained on a selection medium consisting of the above described regeneration medium and containing 25 mg l−1 hygromycin as the selection agent. Approximately 95% of putative transformant shoots expressed the uidA gene following histochemical s-glucuronidase (GUS) assay. These were confirmed to be transgenic by PCR analysis and Southern blot hybridization.

Propagation of Endangered Thermopsis turcica Tan, Vural & Küçüködük Using Conventional and In Vitro Techniques

This report deals with the successful clonal propagation of endangered T. turcica using rhizome cuttings and epicotyl explants. Rhizome cuttings were treated with \alpha-naphthaleneacetic acid (NAA) or indole-3-butyric acid (IBA) before planting for vegetative multiplication. Rhizome cuttings pretreated with NAA (10 mg/L) were both rooted and sprouted (66.6 percent) after 100 days. Application of NAA induced callus and adventitious root formation in epicotyl explants and 6-benzyladenine (BA) induced production of microshoots. Low levels of NAA (0.5-1 \muM) together with BA promoted shoot initiation and development. The highest regeneration rate (86.6 percent), with a mean number of shoots (3.05) and a mean length of shoots (2.3 cm) per epicotyl, was achieved at 10 µM BA and 0.5 \muM NAA. About 83 percent of in vitro regenerated shoots rooted on a ½ Murashige and Skoog (MS) medium supplemented with 0.3 \muM NAA. In vitro plantlets were morphologically normal and a uniform chromosome complement of 2n = 18 was detected in root tips. The study demonstrated that both conventional and in vitro techniques could be useful for large scale multiplication and propagation of this endangered plant species.

Comparison of Shoot Regeneration on Different Concentrations of Thidiazuron from Shoot Tip Explant of Cowpea on Gelrite and Agar Containing Medium

Cowpea (Vigna unguiculata L. Walp) is an important legume grown all over the world as grain crop, animal fodder, cover crop, gren manure and vegetable. The present study compares effects of agar and gelrite on micropropagation from shoot tip explant of two Turkish cowpea cultivars Akkiz and Karagoz using 0.15, 0.15, 0.35 mg/l Thidiazuron (TDZ), 3 g/l activated charcoal, 2 mg/l yeast extract with and without 1.25 mg/l Polyvinylpyrrolidone (PVP). To overcome problem of endogenic bacterial contaminations, all cultures contained 500 mg/l augmentin and incubated at 24 ± 2o C in 16 h light photoperiod for eight weeks. Therafter, all explants were transferred to MS medium for two weeks for shoot regeneration and elongation under same incubation and photoperiod conditions. The results showed that frequency of shoot regeneration increased with increase in TDZ concentrations in both cultivars on both agar and gelrite gelled medium. Both cultivars showed maximum mean number of shoots per explant in gelrite compared to agar gelled medium. Maximum number of 4.72 and 2.86 shoots per explant were recorded on MS medium containing 0.25 mg/l TDZ in cv. Akkiz and cv. Karagoz respectively. Hyperhydricity was recorded on some regenerated shoots, which was more prominant on agar. Agar gelled medium had greater shoot length compared to gelrite medium in both cultivars. Regenerated shoots were rooted easily on MS medium containing 0.50 mg/l IBA with regeneration of mean number of 4 secondary shoots on cv. Akkiz and 3 on cv. Karagoz. Rooted plantlets were successfully hardened in the growth chamber and subsequently established in the greenhouse; where they flowered and set seeds. The recorded survival rate of the plants was 100%. Plants looked healthy with no visible detecTab. phenotypic variations.

Regeneration and characterization of plants derived from leaf in vitro culture of two sweet orange ( Citrus sinensis (L.) Osbeck) cultivars

In the current work attempts were made to investigate culture of leaf explants derived from in vitro seedlings of two sweet orange ( Citrus sinensis (L.) Osbeck) cultivars, Bingtangcheng and Valencia. Effects of several factors, including culture medium, lighting condition, explant age and genotype on regeneration response were examined based on three parameters, percentage of explants producing shoots, mean number of shoots per explant and shoot forming capacity. Culture of the explants on shoot-inducing media (SIM) composed of MT salts supplemented with different growth regulators gave rise to disparate shoot regeneration, in which SIM 1 (MT + 0.5 mg L −1 BA + 0.5 mg L −1 Kinetin + 0.1 mg L −1 NAA + 3% sucrose + 0.8% agar, pH 5.8) was shown to be the most effective medium for direct induction of shoots from leaf explants. Highly significant difference in the response of shoot bud regeneration was noted between the two cultivars, with Bingtangcheng being more responsive than Valencia. Culture of explants from fully developed leaves led to better shoot regeneration capacity in comparison to undeveloped ones. However, the two lighting conditions used herein did not cause significant difference in shoot regeneration. Phenotypic observation and randomly amplified polymorphic DNA (RAPD) analysis confirmed that all the regenerated plants from both genotypes were genetically identical to their donor plants, suggesting absence of detectable genetic variation in the regenerated plants. The data presented here demonstrated that direct initiation of plants from leaf explants has been successfully accomplished. To our knowledge, this is the first report on direct regeneration of shoots from leaf explants in Citrus, which will provide an alternative source for citrus genetic manipulation in the future.

Regeneration of plants from Fraxinus pennsylvanica hypocotyls and cotyledons

An adventitious shoot regeneration and rooting protocol was developed for green ash ( Fraxinus pennsylvanica) seedling explants. The best regeneration medium for freshly isolated hypocotyls and cotyledons was Murashige and Skoog (MS) supplemented with 13.3 μM 6-benzylaminopurine (BA) plus 4.5 μM thidiazuron (TDZ), and 22.2 μM BA plus 4.5 μM TDZ, respectively. Seventy-six percent of hypocotyl segments and 24% of cotyledon segments produced adventitious shoots, with a mean number of adventitious shoots per explant of 2.7 ± 0.5 and 2.3 ± 1.3, respectively. The effect of in vitro-germinated seedling age on adventitious shoot regeneration from hypocotyl and cotyledon explants was also studied. Results showed that hypocotyl and cotyledon explants from freshly isolated embryos exhibited a higher organogenesis potential than 4–15-day-old explants. Adventitious shoots from hypocotyls and cotyledons were established as proliferating shoot cultures following transfer to MS basal medium with Gamborg B5 vitamins supplemented with 10 μM BA plus 10 μM TDZ. A high rooting percentage (73–90%) was achieved when in vitro shoots were rooted on woody plant medium (WPM) containing 4.9 μM indole-3-butyric acid (IBA) and IAA (0, 2.9, 5.7, or 8.6 μM) with a combination of 10-day dark culture period followed by a 16-h photoperiod. The highest rooting (90%) of adventitious shoots or the number of roots per shoot (3.0 ± 1.0) was obtained on WPM with 4.9 μM IBA plus 5.7 μM IAA. Rooted plants were successfully acclimatized to the greenhouse and 100% survived after overwintering in cold storage. This regeneration system using hypocotyls and cotyledons provides a foundation for Agrobacterium-mediated genetic transformation of F. pennsylvanica for resistance to the emerald ash borer.

English

  A micro-propagation system was developed for mangosteen (Garcinia Mangostana L.) using leaf sections and mature seeds. This study investigated the effect of various modified Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurin (BAP) alone or in combination with α-naphthalene acetic acid (NAA) on multiple shoot induction from leaf and half seed explants. Among the treatments, leaf explants on medium supplemented with 2.0 mgLÖ¾¹ (w/v) of BAP gave the highest percentage of shoot formation (70.07%), highest number of shoots formed per explant (46.5%) and showed high mean shoot height (0.48 cm). It was observed that medium with 0.5 mgLÖ¾¹ NAA, did not induce shoot organogenesis, but induced callus in 90% of the leaf explants. Seed explantsgave the highest percentage of shoot formation (60.2%) and mean number of shoots per explant (9.5) on medium supplemented with 20 mgLÖ¾¹ (w/v) BAP and 10 mgLÖ¾¹ (w/v) NAA. However, highest mean shoot height (0.69 cm) was observed on medium supplemented with 10 mgLÖ¾¹ (w/v) BAP and 10 mgLÖ¾¹ (w/v) NAA. Callus induction from seeds was also observed in most of the treatments. Medium-supplemented 20 mgLÖ¾¹ (w/v) NAA gave the highest percentage of callus formation (83.36%). Subsequently, roots were induced from the shoots by pretreating these shoots in various indol-3-butyric acid (IBA) and NAA concentrations in various MS salt strengths. Root formation was obtained on one-quarter strength MS salt medium supplemented with 0.1 mg/L NAA (90.4%). Plantlets were acclimatized on media composed of soil + sand+ organic matter+ vermiculite (2: 2: 1: 1) with 80% survival.   Key words: Garcinia Mangostana L., 6-benzylaminopurine, α-naphthalene acetic acid, Indole-3-butyric acid.

Plant regeneration from in vitro leaves of mature black cherry (Prunus serotina)

A regeneration system was developed for Prunus serotina from a juvenile (F) and two mature genotypes (#3 and #4). Adventitious shoots regenerated from leaves of in vitro cultures on woody plant medium with thidiazuron (TDZ) and naphthaleneacetic acid (NAA). The best regeneration for genotype F (91.4%) was observed on medium with 9.08 μM TDZ and 1.07 μM NAA. The highest mean number of shoots (8.2) was obtained on medium containing 9.08 μM TDZ and 0.54 μM NAA. Genotype #3 had the highest regeneration (41.7%) with a mean number of shoots (4.8) on 9.08 μM TDZ and 1.07 μM NAA, whereas genotype #4 had a 38.8% regeneration with a mean of 3.3 shoots. Genotype #4 had the highest mean number of shoots (4.8) on 4.54 μM TDZ and 1.07 μM NAA. Silver thiosulphate at 60 or 80 μM increased the percent regeneration of the mature genotypes #3 (75%) and #4 (58%). Adventious shoots were rooted (70–76%) and rooted plantlets survived after acclimatization to the greenhouse. The effect of kanamycin concentration on adventitious shoot regeneration was also evaluated.

Somatic embryogenesis and shoot regeneration from leaf derived callus of Hypericum perforatum var. angustifolium (sin. Fröhlich) Borkh

The development of in vitro regeneration systems for Hypericum perforatum var. angustifolium (sin. Fröhlich) Borkh, a medicinal plant used for treating neurological disorders, is described. For the first time in this variety, somatic embryogenesis and shoot regeneration were induced from leaf-derived callus. Well-formed plantlets were obtained through both shoot regeneration and somatic embryogenesis, with separate morphogenetic programmes. Proembryogenic masses were obtained in liquid MS and B5 media supplemented with 5.8 μM 2,4-D, 1.34 μM NAA, and 1.16 μM Kin; after being transferred onto hormone-free medium, they formed whitish and spherical structures that subsequently developed into the heart and torpedo stages. On MS agarized medium containing thidiazuron (TDZ) at different concentrations (3, 6, 9, 12 μM) combined with 2 μM IBA, only shoot regeneration, and not somatic embryogenesis, was obtained. The mean number of shoots increased significantly when the concentration of TDZ was 3 μM.

In vitro propagation of Inula verbascifolia (Willd.) Hausskn. subsp. verbascifolia

A clonal propagation method has been developed for Inula verbascifolia (Willd.) Hausskn. subsp. verbascifolia, a species of horticultural as well as potential medicinal interest. Shoots originating from aseptically germinated seeds were used for culture initiation. The highest multiplication rate of 6.5 shoots per explant was achieved in an 8-week culture period on Murashige and Skoog medium supplemented with 2.2 μM 6-benzylaminopurine and 2.9 μM gibberellic acid. During the first three subcultures of the multiplication phase, two-thirds of explants spontaneously rooted on all tested media. Rooting of excised shoots on MS medium supplemented with 3 μM IAA or 3 μM IBA was 100%. Aside from the fact that all the explants were rooted on this root-inducing media, explants developed a surprisingly high mean number of shoots, 4.6 and 2.9 after 4 weeks, on medium supplemented with IAA or IBA, respectively. Rooted plantlets were transferred to potting soil and acclimatized to outdoor conditions.

Yield, Yield Components, and Forage Nutritive Value of Alfalfa as Affected by Seeding Rate under Irrigated Conditions

Persistence is a critical component of alfalfa (Medicago sativa L.) crop yield. Our objective was to determine the effect of seeding rate on alfalfa persistence, yield, and yield components and how they evolved over time in irrigated areas with long growing seasons. Two alfalfa cultivars were seeded at four seeding rates (10, 20, 30, and 40 kg ha−1), in three consecutive experiments, and evaluated over a 3-yr period to provide total data for nine location years. Seed rates of 10 kg ha−1 [8.75 kg ha−1 of pure live seed (PLS)] produced total 3-yr dry matter (DM) yields of between 50.8 and 58.9 Mg ha−1. Seed rates only affected total 3-yr DM yields in one of the three experiments. The mean number of shoots per m−2 was 488 and this was not affected by seed rates. The effect of seed density on mean shoot weight depended on the experiment. The annual average crude protein (CP) concentration varied from 159 g kg−1 to 224 g kg−1 while the leaf to stem ratio varied from 0.87 to 1.17. The results suggest that CP and leaf to stem ratios (LSR) were either little influenced or not influenced by seed density. The DM yields and yield components indicate that 8.75 kg ha−1 of PLS could be sufficient to ensure adequate DM production. Results also suggest that in a Mediterranean climate in which sprinkler irrigation is applied, there is little justification for high seeding rates under good establishment conditions.

Yield, Yield Components, and Forage Nutritive Value of Alfalfa as Affected by Seeding Rate under Irrigated Conditions

Persistence is a critical component of alfalfa (Medicago sativa L.) crop yield. Our objective was to determine the effect of seeding rate on alfalfa persistence, yield, and yield components and how they evolved over time in irrigated areas with long growing seasons. Two alfalfa cultivars were seeded at four seeding rates (10, 20, 30, and 40 kg ha−1), in three consecutive experiments, and evaluated over a 3‐yr period to provide total data for nine location years. Seed rates of 10 kg ha−1 [8.75 kg ha−1 of pure live seed (PLS)] produced total 3‐yr dry matter (DM) yields of between 50.8 and 58.9 Mg ha−1. Seed rates only affected total 3‐yr DM yields in one of the three experiments. The mean number of shoots per m−2 was 488 and this was not affected by seed rates. The effect of seed density on mean shoot weight depended on the experiment. The annual average crude protein (CP) concentration varied from 159 g kg−1 to 224 g kg−1 while the leaf to stem ratio varied from 0.87 to 1.17. The results suggest that CP and leaf to stem ratios (LSR) were either little influenced or not influenced by seed density. The DM yields and yield components indicate that 8.75 kg ha−1 of PLS could be sufficient to ensure adequate DM production. Results also suggest that in a Mediterranean climate in which sprinkler irrigation is applied, there is little justification for high seeding rates under good establishment conditions.

In Vitro Plant Regeneration from Hungarian Vetch (Vicia Pannonica Crantz) Using Cotyledonary Node Explants

ABSTRACTHungarian vetch is an important forage plant of Southern Europe and South Western Asia. It is progressively gaining popularity as forage plant among farmers of Turkey. In vitro plantlet regeneration in the plant was achieved from cotyledonary node explants on MS medium containing various concentrations of TDZ. The results showed that TDZ concentrations affected frequency of shoot regeneration, mean number of shoots per explants and shoot length in the range of 66.67–100%, 3.28–9.33 and 1.28–3.84 cm respectively. The maximum number of shoots was recorded on MS medium containing 0.45 mg/l TDZ. These were rooted by pulse treatment with 50 mg/l IBA for 7 min and then culturing on 1/2 concentration of MS micro and macro salts and vitamins or MS medium containing 0.30, 0.60, 0.90, 1.20 or 1.60 mg/l IBA. Rooting was more successful on non pulse treated shoots. All of them were put into pots, transferred to growth chamber and then to fields, where they flowered and set seeds.

Micropropagtion of two Strawberries (Fragaria anariassa L.) Cultivars

Shoot tips from two strawberry (Fragaria anariassa L.) cultivars, Gabi and Edpeerenwere cultured on MS medium supplemented with 0, 0.5, 1.0, 1.5 or 2.0mg /1 of BA tostudy their effects on number, length, fresh weight and dry weight of shoots. Thestudy also included measuring the effect of different concentrations of IBA (0 , 0.1 ,0.3 , 0.5 or 1.0) mg / l on rooting percentage, roots number and length. This studyalso included the acclimatization processes for plantlets in sand and a mixture ofsand and peat moss media. Results indicated that addition of BA to the nutrientmedium led to a significant increase in all investigated traits in comparison with the control with obvious superiority of 2 mg /l which reflected positively on the meannumber of shoots (20.0) shoots / plant, the fresh and dry weight were 1237.73 and136.4 mg respectively, especially with Gabi cultivar, the result showed that all thelevels of IBA in the nutrient medium led to 100% rooting after 6 weeks of plantingof both cultivars compared with 50% of in control. It was also noticed significantincreases in the roots number and shoot lengths when IBA concentration wasincreased in the medium. The best growth for the rooted plantlets was found to be1:1 sand: peat moss which showed survival percentages of 80 and 90% after 4weeksof planting Erdpeern and Gabi cultivars respectively.

Rapid micropropagation of Ocimum basilicum using shoot tip explants pre-cultured in thidiazuron supplemented liquid medium

An efficient protocol has been developed for rapid micropropagation of Ocimum basilicum. Multiple shoots were induced by culturing shoot tip explants excised from mature plants on a liquid Murashige and Skoog (MS) medium supplemented with 5-100 µM of thidiazuron (TDZ) for different treatment duration (4, 8, 12 and 16 d). The optimal level of TDZ supplementation to the culture medium was 50 µM for 8 d induction period followed by subculturing in MS medium devoid of TDZ as it produced maximum regeneration frequency (78 %), mean number of shoots (11.6 ± 1.16) and shoot length (4.8 ± 0.43 cm) per explant. A culture period longer than 8 d with TDZ resulted in the formation of fasciated or distorted shoots. The regenerated shoots rooted best on MS medium containing 1.0 µM indole-3-butyric acid (IBA). The micropropagated shoots with well developed roots were successfully established in pots containing garden soil and grown in greenhouse with 95 % survival rate. The regenerated plants were morphologically uniform and exhibited similar growth characteristics and vegetative morphology to the donor plants.