Highest Multiplication Rate Research Articles

Interpretation of clinical trial results: a committee opinion

This document provides guidance, background, and tips on how to recognize quality trials and focuses on evaluating the validity, importance, and relevance of clinical trial results. This document replaces the document of the same name, last published in 2008 (Fertil Steril® 2008;90:S114-20).

In vitro Multiplication of Iraca palm (Carludovica palmata Ruíz & Pavón)

Carludovica palmata Ruíz & Pavón is a plant that belongs to the Cyclanthaceae family. Its commercial interest is related to the production of fibers for the manufacture of handicrafts, mainly the Panama hat, so it is important to study its propagation. This investigation aimed to determine the effect of 6-benzylaminopurine (BAP) in the formation of new shoots and 1-naphthaleneacetic acid (NAA) in the formation of roots, as well as the adaptation in greenhouse conditions of Carludovica palmata Ruíz & Pavón. In order to find the optimal multiplication rate, 0.5 cm length explants were planted in glass jars with 15 mL of semisolid MS with different concentrations of BAP and cultured under in vitro conditions for 90 days. The multiplication parameters in this stage were number of shoots per explant (NSE), length of shoots (LS), and length of roots (LR) as multiplication parameters. In a similar procedure, the number of roots per explant (NRE), length of roots (LR), and length of plantlets (LP) was determined using different concentrations of NAA. Finally, different substrates were evaluated for the adaptation of plantlets of C. palmata produced in vitro, under greenhouse conditions for 80 days. The highest multiplication rate (17±3 shoots per explant) was obtained with 2.0 mg L-1 of BAP. Root formation occurred efficiently in all treatments, without significant statistical differences between them. On the other hand, the use of substrate soil-t15 was the best treatment for the growth of C. palmata under greenhouse conditions. From the results obtained, it is concluded that C. palmata can be efficiently multiplied under in vitro conditions and did not present problems during the in vivo rooting process.

Micropropagation of Chapada Diamantina ornamental bromeliad

ABSTRACT: Sincoraea mucugensis (Wand. & A.A. Conc.) LOUZADA & WAND, an endangered bromeliad, is confined to the central region of the Chapada Diamantina, in the municipality of Mucugê, Brazil. From various researches, it is evident that for the propagation of this species, the in vitro technique is a feasible option. However, due to the low multiplication rates reported in various papers, this study aimed to establish a micropropagation protocol of direct organogenesis for S. mucugensis. First, the inoculation of the stem explants was done in MS ½ culture medium which contained different levels of BAP (0.00; 6.66; 8.88; 11.10; 13.20 µM) and NAA (0.00; 2.60; 5.20 µM). These shoots were then subjected to a couple of distinct rooting periods (of 30- and 60-day duration) using activated charcoal; finally, these microplants were transferred to a greenhouse for acclimatization, and covered with transparent plastic cups, as a water loss prevention test method. All the data were submitted to the analysis of variance (ANOVA), and the means were subjected to regression analysis or compared using the Tukey test. The findings revealed that the S. mucugensis stem explants raised in the NAA-rich medium (6.42 to 7.43 shoots/explants) showed high multiplication rates; the shoot rooting was done for 30 days using activated charcoal with the medium. Acclimatization, which was performed by directly exposing the microplants to the ex vitro environment, showed 95% survival rate.

998 Multiplication Rate of GaAs Avalanche Semiconductor Switch Triggered by 0.567 nJ

In this paper, the results show that the avalanche mode of GaAs photoconductive semiconductor switches (PCSS) requires only a low trigger optical energy of 0.567 nJ to achieve. At the bias electric field is 94 kV/cm, a trigger optical energy with sub-Nano Joule is used to trigger the PCSS, and the multiplication rate can be as high as 988. We have presented avalanche delay characteristics under the different bias electric voltage, and the physical mechanism of the avalanche delay time is analyzed. This article shows a high multiplication rate ultrafast pulse source with low-energy triggering.

RNA-Seq analysis of Orobanche resistance in Nicotiana tabacum: development of molecular markers for breeding recessive tolerance from ‘Wika’ tobacco variety

Orobanche spp. (broomrape) is an obligate root parasite that can attack a wide spectrum of plants, including tobacco. It has been responsible for economic losses in Europe since 2002 and its incidence in many tobacco-growing countries is increasing. Preventive and curative methods exist, including the use of agrochemicals, however efficacy is limited and pest dissemination remains important due to a high rate of multiplication of the parasite and very small long lasting seeds. The tobacco variety ‘Wika’ induces lower or delayed germination of Orobanche seeds. This seems to be conditioned by a single recessive gene (Cailleteau et al. in: CORESTA Congress, Paris, 2006). Artificial testing in Petri dishes was developed to evaluate the ability of tobacco plantlets to stimulate seed germination. Different lines derived from ‘Wika’, with susceptible control lines, were tested and studied by RNA-Seq. Candidate markers including SNPs or genes differentially expressed between susceptible and resistant lines were identified. An F2 population segregating for ‘Wika’ recessive tolerance was then used for marker validation and mapping. All candidates were situated on chromosome 14 of the tobacco genetic map. The Nicotiana variety collection from Imperial Brands was also tested for these markers, highlighting or confirming other potential tolerant lines. KASP™ genotyping or markers for conventional gel electrophoresis are now available to drive the transfer of ‘Wika’ recessive tolerance into elite lines. RNA-Seq technology combined with sound experimental testing has again proven its high efficiency to identify useful markers for tobacco breeding.

Micropropagation of Rosaceous Species SAM Grown in Temperate Climate.

The benefits of in vitro plant cultivation are mainly due to very high multiplication rate. Cultivation of plant material in vitro can be carried out during the whole year regardless of the time of the year or weather conditions. We create artificial conditions in the lab (heat, light, humidity), and we can regulate these conditions at any time. For the preservation of cultivar identity, we recommend establishing in vitro cultures from shoot tips usually larger than 0.2mm. In practice, in vitro cultivation of plants uses these growth regulators to achieve organogenesis, for example, root formation, prolonged growth, or multiplication. During each subculture, these cultures are then transferred on a solid agar medium in the form of actively growing multiple shoots with a well-differentiated shoot tip containing meristematic area. Cytokinins are important for cell division and causes branching of plants. Auxins, both endogenous and exogenous, act at as a trigger for the differentiation and formation of root primordia. Morphological characteristics (formation of leaves or callus) and shoot development should be observed during in vitro multiplication and after transfer to ex vitro conditions.

THE INFLUENCE OF GROWTH REGULATORS ON DAHLIA PROPAGATION IN TISSUE CULTURE AND ACCLIMATIZATION OF PLANTS IN ex vitro CONDITIONS

The aim of work was to evaluate the influence of cytokinins on dahlia propagated in vitro and their consequent effect on acclimatization. Plant material were shoot tips and nodes. From three cytokinins, benzyladenine, kinetin and 2-isopentenyl-adenine, only BA effectively stimulated shoot multiplication from axiliary buds. The highest multiplication rate was obtained from nodes in presence of 0.25–0.5 mg·dm–3 BA. Higher concentrations shortened internodes and decreased leaf blades and growth of callus. 1 mg·dm–3 of KIN and 2iP positively influenced shoots growth and size of leaves. Gibberellic acid (GA3) used with BA increased the number of axillary shoots. The best quality shoots and the highest multiplication rate were obtained when 2 mg·dm–3 BA was used with 5 mg·dm–3 GA3. Cytokinins affected rooting and acclimatization ex vitro. Dahlias shoots multiplicated in presence of 1 mg·dm–3 KIN or 2iP rooted faster in the soil and 100% survived in field, while those from 1 mg·dm–3 BA media rooted slowly, had shorter shoots and only 60% survived. Plants bloomed after 11–12 weeks in the field. Dahlia plants that had been multiplicated in presence of KIN had a bigger diameter and fresh weight in the field. BA and 2iP positively influenced flowers diameter, length of flower stalk and a number of first order shoots.

Perinatal complications and live-birth outcomes following assisted reproductive technology: a retrospective cohort study.

BackgroundWith the development of assisted reproductive technology (ART) and its increasing success rate in the mainland of China, more attention has been paid to the safety of ART. In this study, we explored the associations between conception by ART and pregnancy/perinatal complications, and neonatal outcomes compared with similar outcomes following spontaneous conception.MethodsThis retrospective cohort study of pregnancies over a 3-year period (2013–2015) was performed at Beijing Obstetrics and Gynecology Hospital, Beijing, China. Subjects were divided into two groups: conception by ART (n = 2256) or spontaneous conception (n = 6768). According to different fertilization modes, the ART group was divided into in vitro fertilization (IVF, n = 1873) and intracytoplasmic sperm injection (ICSI, n = 383) subgroups. The ART group was also divided into two different embryo transfer methods; fresh embryo transfer (ET, n = 1583) and frozen embryo transfer (FET, n = 673) subgroups. Pregnancy complications, perinatal complications, and neonatal outcomes of the enrolled subjects were investigated and analyzed by univariate analysis and multivariate logistic regression.ResultsAfter adjustment for maternal age, gravidity, parity, maternal education, smoking, alcohol consumption, and body mass index (BMI), pregnancies conceived by ART were associated with a significantly increased incidence of gestational diabetes mellitus (GDM; OR 1.88, 95% CI 1.56–2.27), gestational hypertension (OR 2.18, 95% CI 1.83–2.60), and intrahepatic cholestasis of pregnancy (ICP) (OR 2.79, 95% CI 2.15–3.64), compared with spontaneous conception. These associations were similar for the singleton group. In the twin group, only the incidence of ICP was significantly higher than in controls. We found that pregnancies conceived by ART were associated with perinatal complications, including placental abruption (OR 2.14, 95% CI 1.33–3.45), premature rupture of membranes (PROM; OR 1.24, 95% CI 1.06–1.45), postpartum hemorrhage (OR 2.89, 95% CI 2.33–3.59) and polyhydramnios (OR 2.01, 95% CI 1.29–3.16). The singleton group had a similar result with placental abruption, but not with fetal membranes ruptures before labor and polyhydramnios. There were no significant differences in the incidence of these perinatal complications in the twin group. Some neonatal outcomes, including preterm labor (OR 4.29, 95% CI 3.84–4.80) and low birth weight (OR 1.72, 95% CI 1.42–2.08), were more likely to occur with singleton births after ART. However, there were no significant differences for these outcomes from twin pregnancies. Perinatal complications and neonatal outcomes were consistent between the IVF and ICSI subgroups. The FET and ET subgroups showed a similar increase in complications, except for the incidence of placental abruption. After taking into account the effects of parity, birth plurality and maternal age, the ART group still exhibited increased maternal and neonatal complications, although some differences narrowed or disappeared.ConclusionsThis retrospective cohort study demonstrated that patients who underwent ART were at increased risk of several adverse pregnancy outcomes compared with women who conceived spontaneously. These complications may be attributed in part to the relatively high multiple pregnancy rate after ART. Elective single embryo transfer should be promoted in China to reduce the obstetrical risks of ART pregnancy. Singletons of ART pregnancy exhibited increased maternal and neonatal complications as well, suggesting that underlying infertility or other maternal or parental factors may contribute to the adverse outcomes.

Trigonelline's effect on BCL-2 protein expression level in THP-1 cells

Dracocephalum forrestii is a perennial, endemic to China plant with a number of pharmaceutical properties. Transformed shoots of the species spontaneously regenerated from hairy roots induced by Agrobacterium rhizogenes. The transgenic nature of the shoots was confirmed by polymerase chain reaction (PCR). The shoot culture was multiplied on Murashige and Skoog (MS) medium with 0.2 mg/l IAA and 0.2, 0.5, 1.0, 2.0 or 5.0 mg/l purine-type cytokinins (mT, BAR, BPA or BAP). The highest multiplication rate (about thirteen shoot or buds per explant) was obtained on MS medium with 0.2 mg/l mT after four weeks of culture. The phenolic compounds present in the hydromethanolic extracts from the D. forrestii transgenic shoots were characterized using UPLC–PDA–ESI–MS. The shoots were found to biosynthesize three phenolic acids and five flavonoid glycosides. UHPLC analysis of the hydromethanolic extracts found the predominant phenolic acid to be rosmarinic acid, with its highest content observed in shoots cultivated with 5.0 mg/l BPA. In contrast, the greatest production of flavonoid derivatives (especially acacetin derivatives) was observed in the medium supplemented with 2 mg/l BPA.

Propagation of three Blue Honeysuckle (Lonicera caerulea L.) cultivars in in vitro culture

The aim of this study was to micropropagate three blue honeysuckle cultivars "Kalinka", "Polar Jewell" and "Balalaika". Driver and Kuniyuki medium (DKW) with different type and concentrations of plant hormones for in vitro shoot multiplication. For in vitro rooting was used Driver and Kuniyuki medium (DKW) and Murashige and Skoog medium (MS) with different concentrations of indol-3-butyric acid (IBA). The highest multiplication rate was obtained on DKW medium supplemented with 4 mg L-1 6-benzylaminopurine (BA) and 1 mg L-1 indole-3-butyric acid (IBA) for cultivars "Balalaika" and "Polar Jewell", while of cultivar "Kalinka" with DKW medium and 2 mg L-1 6-benzylaminopurine (BA) and 0.5 mg L-1 indole-3-butyric acid (IBA). The best microshoot rooting rates were obtained on DKW basal nutrient medium with 1 mg L-1 indol-3-butyric acid (IBA).

The effect of purine-type cytokinin on the proliferation and production of phenolic compounds in transformed shoots of Dracocephalum forrestii

Dracocephalum forrestii is a perennial, endemic to China plant with a number of pharmaceutical properties. Transformed shoots of the species spontaneously regenerated from hairy roots induced by Agrobacterium rhizogenes. The transgenic nature of the shoots was confirmed by polymerase chain reaction (PCR). The shoot culture was multiplied on Murashige and Skoog (MS) medium with 0.2 mg/l IAA and 0.2, 0.5, 1.0, 2.0 or 5.0 mg/l purine-type cytokinins (mT, BAR, BPA or BAP). The highest multiplication rate (about thirteen shoot or buds per explant) was obtained on MS medium with 0.2 mg/l mT after four weeks of culture. The phenolic compounds present in the hydromethanolic extracts from the D. forrestii transgenic shoots were characterized using UPLC–PDA–ESI–MS. The shoots were found to biosynthesize three phenolic acids and five flavonoid glycosides. UHPLC analysis of the hydromethanolic extracts found the predominant phenolic acid to be rosmarinic acid, with its highest content observed in shoots cultivated with 5.0 mg/l BPA. In contrast, the greatest production of flavonoid derivatives (especially acacetin derivatives) was observed in the medium supplemented with 2 mg/l BPA.

Multiplicação in vitro de Neoregelia johannis (Carriére) L.B. Smith em meio líquido sob diferentes concentrações de nutrientes

The importance of micropropagation to Bromeliaceae species is increasing, however few studies report the role of nutrition in in vitro multiplication. In order to correlate micropropagation morphophysiological aspects with regards to availability of nutrients, mainly nitrogen, Neoregelia johannis shoots were subcultured in the media culture MS, ½ MS and WPM, supplemented with the same concentrations of plant growth regulators. The multiplication rate was similar for all the culture media, with the highest multiplication rate, in addition to the highest accumulation of total and protein nitrogen, in the MS culture medium. Even producing the smallest shoots, the means of cultivation ½ MS and WPM represent a viable alternative for the maintenance of germplasm bank and for the maintenance of important genotypes in plant biofactories, considering that they present uniform results. The MS medium culture would be recommended for specific cases, when it is necessary to accelerate the multiplication and especially the growth of the shoots.

The influence of explants type and orientation on growth and development of Mandevilla sanderi (Hemsl.) Woodson in vitro

Mandevilla sanderi is an important commercial ornamental pot plant. Traditional vegetative propagation is limited due to the low rate, therefore there is a need to develop an alternative, more efficient method. There is an interest in development of micropropagation technology for the species, as it allows to obtain a lot of offsprings in a relatively short time. The aim of the present work was to estimate an influence of explants type and position on regeneration of Mandevilla sanderi in tissue culture. Four different types of explants (leafy shoot tips, decapitated leafy shoot tips, defoliated shoot tips, decapitated and defoliated shoot tips) were used in the experiment, which were placed on the media vertically, while defoliated shoot tips were placed horizontally or vertically upside down. The explants were cultivated on a Murashige and Skoog (MS) medium supplemented with 1 mg·dm–3 benzyladenine (BA) and 0.5 mg·dm–3 indole-3-butyric acid (IBA). It was noted that both explants orientation and positioning, influenced the multiplication rate. Defoliated shoot tips placed horizontally were characterized by higher multiplication rate (6.8) in comparison to upside down vertical positioning (3.2). It was also observed that removal of shoot apex improved axillary branching, while defoliation of shoots placed in a normal position reduced multiplication rate.

Multiplicação in vitro de Xylopia aromatica em diferentes meios de cultura e concentrações de BAP

Este estudo teve por objetivo desenvolver uma metodologia de multiplicação in vitro para Xylopia aromatica, visando a produção de mudas, avaliando-se meios de cultura e concentrações de reguladores de crescimento mais adequados. Foram utilizados, como explantes, segmentos nodais, provindos de brotações de mudas produzidas via seminal e mantidas em viveiro. Foram testados os meios de cultura Murashige Skoog (MS) e Wood Plant Medium (WPM) suplementados com 800 mg L-1 de polivinilpirrolidona (PVP), 30 g L-1 de sacarose, 0,054 µM de ácido naftalenoacético (ANA) e 6 g L-1 de ágar e concentrações de 2,22 e 3,55 µM de benzilaminopurina (BAP) para a multiplicação in vitro. Aos trinta dias, avaliou-se o número de brotações laterais emitidas e o percentual de explantes formando calos na base. As maiores taxas de multiplicação foram obtidas com o meio MS acrescido de 3,55 µM de BAP. Em relação à formação de calos na base dos explantes, o meio MS promoveu maior formação quando comparado ao WPM, no entanto não comprometeu a formação de brotos. Foi possível estabelecer as fases de introdução e multiplicação, definindo assim o meio de cultura e concentrações de reguladores de crescimento mais adequados ao cultivo in vitro de Xylopia aromatica.

Development of a new culture medium and efficient protocol for in vitro micropropagation of Ceratonia siliqua L.

A new basal culture medium was developed and tested using a rapid and efficient protocol of in vitro axillary shoot bud proliferation of Ceratonia siliqua L., an important Mediterranean Fabaceae plant species. In a first experiment, the new formulated ‘LA’ mineral composition significantly improved shoot growth and proliferation as compared with Murashige and Skoog medium (MS, 1962) in both solid and liquid culture media. However, the liquid culture system proved to be the most suitable for shoot induction, shoot length (about fourfold higher), and multiplication rate (about two-fold higher), the difference being significant. The measured growth and proliferation parameters were further improved when LA mineral composition was optimized, in a second experiment. The highest multiplication rate (6.3) was achieved during the second subculture using the optimized ‘LAC’ medium. Noticeably, hyperhydricity and shoot-tip necrosis symptoms were absent in both formulated LA and LAC compositions when using the liquid culture system. In vitro rooting in solid medium showed 41.7 to 46.3% response on a solid medium which was more suitable than the liquid culture system, the difference being significant. In contrast, pretreated microcuttings with 3 μM IBA (indole-3-butyric acid) were successfully rooted ex vitro, showing significantly higher response (91.7%), average root number (8.3), and root length (31.5 mm). The plantlets were successfully acclimatized showing more than 90% survivability and normal morphology. The present study is a first cost-effective protocol for carob micropropagation combining the use of the newly formulated LAC basal medium, a liquid culture system, and ex vitro rooting.

Argylia radiata micropropagation, a biotechnological tool to domesticate a new ornamental crop

Argylia radiata (L.) D. Don (family Bignoniaceae) is a perennial plant, native to the north of Chile. It is considered as a potential candidate as an ornamental crop. Micropropagation was evaluated as part of the domestication process. A multiplication trial was performed using MS medium supplemented with three cytokinins, 6-benzylaminopurine (BAP), kinetin, and zeatin, at four different concentrations (0.5, 1.0, 1.5, and 2.0 mg L‑1) and hormone-free medium as a control. After 5 weeks, the number of sprouts, multiplication rate, plant height, and plant damage were measured. Fresh weight, dry weight, and water content of the plants were determined as well. Medium containing 1.0 mg L‑1 BAP produced the greatest shoot emission (8.45 sprouts per plant). The highest multiplication rate (7.22 explants per plant) was observed with 2.0 mg L‑1 BAP and the lowest was observed in kinetin media. Zeatin-supplemented media showed an increase in the number of damaged plants, but no damage was observed in the plants cultured in hormone-free medium. Plants in control medium and kinetin-supplemented media showed the lowest fresh and dry weights, while those in medium containing 2.0 mg L‑1 BAP had the highest. The plantlets in hormone-free medium had the lowest water content. Finally, the best multiplication rate was obtained in media supplemented with BAP and zeatin mediums.

Micropropagation of clonal lines of thorny artichoke (Cynara scolymus L.)

The aim of the study was to evaluate the in vitro propagation ability of 10 clonal lines of thorny globe artichoke ( Cynara scolymus L.). The study methodology comprised five stages of evaluation. The stages evaluated were initiation, multiplication, rooting, acclimatization, and transplant to the field. The study began with the initiation of dissected shoot tips of 10 clonal lines in test tubes containing the Murashige and Skoog (MS) medium. Best results were obtained when explants were cultured on an induction medium containing MS + naphthalene acetic acid (NAA) 1.0 mg l−1 + benzyl aminopurine (BA) 1.0 mg l−1, highlighting clonal lines L-250, L-132, and L-62. Because of high rates of vitrification and phenolization in the initial stage, clonal lines L-24, L-127, and L-142 were discarded from the study. Therefore, only seven clonal lines were included for evaluation in the multiplication stage. Once the microplants were obtained under laboratory condition in the culture medium, they were immediately transferred to a proliferation medium containing MS + BA 1.0 mg l−1. Only in three clonal lines (L-132, L-200, and L-250), a high multiplication rate (3.5 shoots/explant) was achieved with axillary bud formation. Of the seven clonal lines evaluated, clonal line L-250 achieved the highest rates in the variables shoot height (3.38 cm), number of leaves (13.4), and number of shoots/explant (4.4). In the rooting stage, clonal line L-250 obtained a significant improvement by transferring plantlets to direct acclimatization after 20 days of in vitro root induction in a medium containing MS + NAA 1.0 mg l−1. Similarly, in the acclimatization stage, the clonal line L-250 showed a significant result. Then, in the transplantation stage, the plants were transplanted to the field with 100% rooting; 30 days after the transplantation, the clonal line L-250 obtained 100% survival in the field than the control treatments (offspring from two locations were used – Mito and Alayo). As the rooting period is reduced by approximately 20 days by inducing direct root formation under greenhouse conditions, the micropropagation technique is optimized with the protocol used in this study.

Morphogenesis and in vitro production of caffeoylquinic and caffeic acids in Baccharis conferta Kunth

We established a protocol for the in vitro propagation of Baccharis conferta Kunth. This plant is used to treat gastrointestinal problems, cramps, pain, respiratory problems, and insect bites. A high rate of shoot multiplication was obtained from nodal segments on Murashige and Skoog (MS) culture medium. The shoots regenerated roots without exogenous plant growth regulators (PGRs). All explants of wild leaves on MS medium containing 5 μM of thidiazuron (TDZ) produced friable callus. An organogenic response was achieved after 3 wk of culture when callus segments were transferred to MS medium containing a combination of plant growth regulators (PGRs): either (i) 5 μM indole butyric acid (IBA) + 5 μM kinetin (KIN) or (ii) 0.5 μM IBA + 1.10 μM benzylaminopurine (BAP). The morphogenetic responses of callus were characterized by scanning electron microscopy. Shoots regenerated from callus and formed roots on MS medium without PGRs. The micropropagated plantlets and the organogenic callus showed similar chemical profiles in HPLC-mass spectrometry analyses. The main compounds present in the cultures were caffeoylquinic acids. Only plantlets contained small amounts of triterpenes (erythrodiol and ursolic acid). These findings will be useful for the micropropagation of this important native resource, and for further studies on its biology.

A new temporary immersion system for commercial micropropagation of banana (Musa AAA cv. Grand Naine)

Temporary immersion systems (TIS) are among the best options for commercial micropropagation. However, although successes have been reported with TIS, it is necessary to establish the most suitable system. The aim of this research was to compare the efficiency of different banana (Musa AAA cv. Grand Naine) micropropagation systems. In addition, a liquid medium with partial immersion and a semi-solid culture medium were evaluated. At 28 d of culture, the number and length of shoots, number of leaves per shoot, chlorophyll content, stomatal index, and the percentage of closed stomata were recorded. Additionally, the survival percentage and ex vitro development of the plantlets were evaluated during acclimatization. Results showed that TIS have a higher multiplication rate with respect to partial immersion and semi-solid medium. The chlorophyll content, stomatal index, and stomata functioning were affected by the different culture systems. The different culture systems had no effect on the survival percentage, although morphological differences were observed during acclimatization. The SETIS™ bioreactor was more efficient and resulted in better development in the plants obtained in vitro and ex vitro, which proved this system to be a useful alternative for banana micropropagation.

Studies on genetic fidelity of long term micropropagated culture derived plants of Ofra strawberry using molecular markers

Availability of good plant material of a required cultivar ‘Ofra’ in a large quantity is a major limitation in expansion of strawberry cultivation. Keeping in view this problem, regeneration through in vitro culture has now become a viable and alternate method to conventional one. The formation of healthy shoots and higher rates of multiplication is one of the pre-requisite of an economically viable propagation. Somaclonal variations have been observed in the plants raised through tissue culture, which defeats the purpose of producing true-to-type plants. Therefore, need arises to study the genetic fidelity of tissue culture raised strawberry (Fragaria× ananassa Duch.) cv ‘Ofra’ plants. Runners of strawberry cv ‘Ofra’ used as explants and cultured on MS supplemented with 2mg/l GA3, 2.0 mg/l BA, 100 mg/l of meso inositol and 30g/l of sucrose gave best results for in vitro shoot multiplication. DNA from fresh, young and healthy leaves of 14 in vitro raised plants and mother plant of Strawberry cv “Ofra” was isolated following CTAB method. Random amplified polymorphic DNA and inter simple sequence repeat analysis were carried out with 15 and 20 primers out of which 7 and 14 primers produced three and 8 monomorphic bands respectively, for genetic stability studies of the regenerated plants. Comparison of the bands with the mother plant revealed the monomorphic nature and true to type clones. The above regeneration protocol of Strawberry (Fragaria × ananassa Duch.) cv ‘Ofra’ will be useful for micropropagation and genetic transformation studies.