Bulb Induction Research Articles

Bulb Induction on Madonna Lily Stems and Three Years Growing Performance of the Bulblets

Currenly, Madonna lily (Lilium candidum L.) is considered as one of the most important ornamental and perfumery plants. Madonna lily is currently propagated via seed or bulb scales. However, seed derived plants reaches sexual maturity at the end of five years and flower production is interrupted in vegetative propagation via bulb scales because fertile bulbs are needed as source of scale. To overcome the two obstacles, stems of mature plants were used as material for bulb production in the current study. For this purpose, the stems, obtained from plants at the end of flowering were stored in cardboard boxes under the conditions of darkness, normal temperature and pressure (20°C and 1 atm) during four months. At the end of this period, it was observed that 14 bulbs per stem formed on the stored stems. The stem derived bulbs were cultivated in pots and were observed to determine their development performances and some morphological characters until reaching flowering during three years. An increase of 226% in bulb weight, 51.2% in bulb diameter and 58.9% in bulb circumference were observed at the end of the three years. In this study, a new and effective method for Madonna lily propagation was described for the first time.

The Effect of Different Applications on In vitro Bulb Development of an Endemic Hyacinth Plant (Hyacinthus orientalis L. subsp. chionophyllus Wendelbo) Grown in Turkey

In this study the effects of different sucrose concentrations, and the combinations of jasmonic acid (JA) with auxins (IAA or NAA) or with cytokinin (2iP) on the bulb induction and rooting of in vitro plantlets of Hyacinthus orientalis subsp. chionophyllus Wendelbo, which is endemic in Turkey, were investigated. The effect of four different sucrose concentrations (30, 45, 60 and 90 g L-1) on bulb formation in tissue culture was investigated. These plantlets were cultured on MS medium supplemented with several concentrations and combinations of JA (0.0, 1.0, 2.0 mg L-1) and 2iP (0.0, 0.25 and 0.50 mg L-1), IAA or NAA (0.5, 1.0 mg L-1). In JA- 2iP treatment, the highest number of bulblets (13.7 number/explant) was obtained by the combinations of JA 1.0 mg L-1 + 2iP 0.25 mg L-1. Also, the largest bulblets with the mean diameter of 7.9 mm were found on MS medium supplemented with JA 2.0 mg L-1. In JA – Auxin treatment, the mean root number per bulblet was highest (17.9 number/explant) and root formation rate was maximum (81.14%) on MS medium supplemented with IAA 1.0 mg L-1 + JA 2.0 mg L-1.

Propagation and Bulblet Enhancement of Rhodophiala pratensis from Seeds Germinated In Vitro

Rhodophiala pratensis is an endemic geophyte from Chile with great importance to the national market of cut flowers and potted and garden plants. However, many geophytes have conservation issues and are considered endangered species. Efficient and controlled propagation techniques have been useful for the commercial production of this species and for its conservation. A micropropagation protocol using seeds was developed to determine an optimum method to increase bulb production rates and plant production. The effect of sucrose levels in the medium on the growth of bulbs was tested in vitro (30, 60 and 90 g L -1 ). Then, the effects on shoot and bulb induction of the cytokinin BAP at concentrations of 1.0, 2.0 and 4.0 mg L -1 with the auxin NAA at concentrations of 0.1, 1.0 and 2.0 mg L -1 were analyzed. The germination rate after eight weeks increased to 86% with very low contamination (7%). Bulb growth increased when high levels of sucrose were added to the medium; the optimum sucrose concentration was 90 g L -1 . Acclimatization was successful, with a plant survival rate of 63% and an average bulb growth of 0.5 cm. This is the first study to demonstrate the possibility of propagating R. pratensis seeds in vitro.

Comparison of Outpatient Foley Bulb Induction to Traditional Induction of Labor [18J

INTRODUCTION: More than 20% of pregnant women in the U.S. undergo induction. Due to an unfavorable cervix, many of the women presenting for induction experience longer labor times, increased rates of cesarean section and increased healthcare costs. The purpose of the study was to examine the difference in cesarean section rates, maternal and neonatal morbidity and costs for outpatient vs inpatient Foley induction. METHODS: We conducted a retrospective case control study using data from the Kaiser Permanente electronic medical record for the Orange County Service area. Cases were identified using a log of all patients receiving Foley bulb placement. Controls were identified through the electronic health record using Current Procedural Terminology codes and International Classification of Diseases 9th Revision codes for induction of labor from 2013-2015. Cases and controls were matched by advanced maternal age status, parity and race. Patients were excluded if they had a modified bishop score >6 or nonvertex presentation or <37 weeks gestation. RESULTS: Between 9/2013 and 12/2015, 283 cases were identified and matched 1:1 to controls. There was no difference between cases and controls for rate of cesarean (P>0.89) or for maternal (P>0.37) or neonatal morbidity (P<0.5). Cases were more likely to have an infant with a higher birth weight (P<0.01), have a shorter length of hospitalization for labor and delivery (P<0.01) and lower costs of hospitalization (P<0.01). Cost was quantified, with average 300 dollars per patient savings for outpatient induction. CONCLUSION: Outpatient Foley bulb placement is a safe, cost effective alternative for women undergoing induction of labor.

43: A randomized trial of Foley bulb induction of labor trial in nulliparas (FIAT)

43: A randomized trial of Foley bulb induction of labor trial in nulliparas (FIAT)

Endogenous cytokinin dynamics in micropropagated tulips during bulb formation process influenced by TDZ and iP pretreatment

There are substantial variations in bulbing (bulb formation) efficiency among micropropagated tulip cultivars. The mechanisms involved are poorly understood, but presumably involve cytokinins (CKs) for several reasons. Therefore, we explored CK profiles and dynamics in ‘Blue Parrot’ and ‘Prominence’ cultivars (which have low and high bulbing efficiency, respectively) during the in vitro propagation stages: the last shoot multiplication subculture extended to 14 weeks (S1–S2), the shoot cooling at 5 °C for induction of bulb formation (S3–S4) and the bulb growth initiation after the end of cooling (S5–S6). The CK thidiazuron (TDZ) is routinely used in tulip micropropagation at the shoot multiplication stage, but replacing it with isopentenyladenine (iP) during the last multiplication subculture substantially changed CK dynamics in later stages, and significantly increased bulb formation rates in both cultivars. Generally, the most abundant CKs in both cultivars were the isoprenoid CK types, trans-zeatin (tZ), iP, cis-zeatin and dihydrozeatin. However, ‘Prominence’ shoots had much lower cis- to trans-Z-type CK ratios than ‘Blue Parrot’ shoots, and generally higher levels of physiologically active CKs (free bases tZ, iP and their ribosides) until the last phase of bulb formation, S6 (bulb growth initiation, i.e. swelling of shoot bases), 6 weeks after the end of cold treatment. In this phase total active CK and O-glucoside contents sharply declined in ‘Prominence’ shoots, but not in ‘Blue Parrot’ shoots pretreated with iP. In contrast, the low bulbing ability observed in ‘Prominence’ shoots pretreated with TDZ and ‘Blue Parrot’ shoots pretreated with either TDZ or iP was associated with a gradual rise in active CK and O-glucoside contents after the end of cooling. The results suggest that low bulbing efficiency may be related to down-regulation of tZ biosynthesis, and high bulbing efficiency to a transient increase in active CK forms (mainly tZs) in response to cold treatment during the bulb induction phase, S4 (at the end of cold treatment), followed by a rapid decrease during bulb formation, S6 (6 weeks after the end of cooling).

Micropropagation of Albuca bracteata and A. nelsonii — Indigenous ornamentals with medicinal value

In this study, two species from the genus Albuca (Hyacinthaceae) with ornamental and medicinal properties were micropropagated. Adventitious bulblets of Albuca bracteata were cut into quarters and used as explants to examine the effect of temperature (10, 15, 20, 25, 30 or 35 °C), carbohydrates (glucose, fructose or sucrose at 0, 87.5, 175, 262.5 or 350 mM) and hormones (BA, mTR, NAA, IAA, GA 3, ABA or methyl jasmonate each at 0, 0.1, 1.0 or 5.0 mg/L) on the induction and growth of bulblets. Temperatures above 35 °C completely inhibited bulb formation, while induction at all other temperatures was high. Heaviest and largest bulbs formed at 20 °C. Low concentrations (87.5 mM) of all tested carbohydrates increased bulb induction compared to media without a carbohydrate source, while higher levels decreased bulblet induction. The cytokinins mTR and BA inhibited bulb induction, diameter and mass at moderate (1.0 mg/L) and high (5.0 mg/L) concentrations. GA 3, NAA and particularly IAA promoted bulblet induction, while ABA and methyl jasmonate had no significant effect on the induction or bulblet growth. Leaf material and young inflorescences of A. nelsonii were removed, decontaminated, and dissected into seven explant types: leaves, peduncles, pedicels, whole flowers, tepals, ovaries and anthers. These were placed on MS media without hormones, or containing 0.5 mg/L mTR, 0.5 mg/L NAA or 0.5 mg/L mTR + 0.5 mg/L NAA to establish which explant type and hormone combination promoted shoot formation. Some tepal and pedicel explants were capable of shoot production on media with both mTR and NAA, but peduncle explants produced the most shoots when mTR and NAA were both present in the culture medium. Flowers, leaves, ovaries and anthers were completely unresponsive, irrespective of medium composition. These techniques will aid the further horticultural development of these plants, and can be easily adjusted for other species within the genus to promote conservation.

In vitro bulb formation of Narcissus asturiensis, a threatened species of the Amaryllidaceae

SummaryThe culture conditions for in vitro production of bulbs of Narcissus asturiensis were determined. The process was initiated using twin-scales as primary explants that were cultured on a modified MS medium supplemented with IBA (4.9 μM) 1 BA (8.87 μM) or NAA (0.65 μM) 1 BA (26.6 μM). Both media were appropriate for shoot induction and proliferation, although the multiplication rate of leafy shoots was higher on the medium with NAA and BA. After 60 d of culture on both media, tiny bulb-like structures appeared at the base of the leaves; however, the medium with IBA was the most suitable for bulb induction. Further growth of the bulbs was achieved on a similar basal medium with only NAA and with an increased sucrose content (9%). After 90.d of culture on this growth medium, bulbs attained a mean diameter of 8 mm but the production of roots was low. Root induction was performed on four rooting media (MS salt solution with NAA or IBA and half strength MS salt solution with NAA or IBA), the highest number of rooted bulbs was on the medium with reduced inorganic salt concentration plus NAA. Rooted bulbs adequately prepared for ex vitro culture were then transferred to a glasshouse and the success of transplantation is under evaluation.

Non-structural carbohydrate composition of long-day onion in vitro

SummaryBulb formation in onion (Allium cepa L.) is strongly influenced by environmental factors, particularlyby light via photosynthesis and daylength. Dry-matter content (DM) in an onion bulb varies between 6 and 25%. Of this, 60–80% is made up of non-structural carbohydrates (NSC). This study compared the relative influence of genetics and environment on the concentration and composition in NSC of onion bulbs. The effects of clonal genotype, light spectrum quality and sucrose concentration in the culture medium were investigated in vitro on a long-day onion type. NSC analyses were performed enzymatically and by HPLC on growing material. Fructans characterized the basal tissues, and the sucrose content in the medium influenced the NSC distribution of the onion tissues. Bulb induction by supplementary incandescent light stimulated fructan accumulation in basal tissues. The high DM clones stored fructans faster and at higher concentrations than the low DM ones. They expressed a higher potential for fructan sink or biosynthesis. A similar biochemical composition in vitro as field-grown bulbs resulted from the light spectrum quality of light.

The effect of jasmonic acid, sucrose and darkness on garlic (Allium sativum L. cv. Ptujski jesenski) bulb formation in vitro

The effect of sucrose, jasmonic acid (JA) and darkness on bulb formation of garlic Allium sativum L. cv. Ptujski jesenski was studied in vitro. B5 medium supplemented with 3% sucrose, 5 µM JA and 5 µM 2-isopentenyl adenine (2iP) was used for shoot induction on garlic basal plates. For bulb induction, explants with developed shoots were transferred onto media with 3% or 8% sucrose in the presence or absence of 5 µM JA. Sucrose (8%) significantly increased the percentage of shoots which formed bulbs by 86–90%, bulb diameter and the number of bulbs per basal plate. On medium supplemented with JA, the average number of bulbs per basal plate was 11.5. Growth of explants in the dark was ineffective for stimulating bulb formation. Simultaneous use of JA and sucrose can improve garlic micropropagation via bulb formation, without intermediate callus formation.

In vitro bulb production fromAllium spp.

A procedure for bulb formation from onion, garlic, and shallot explants is described. Explants from cut stem bases were cultured in shoot induction medium composed of Murashige and Skoog (MS) medium with or without N6-benzyladenine. Shoots produced were then transferred to bulb induction medium composed of MS medium containing 5 g/liter activated charcoal and 120 g/liter sucrose under a long-day photoperiod and 28° C. Bulbs were also produced from onion and garlic directly, without passing through shoot formation, when explants were cultured in the bulb induction medium described above. Bulbs were transferred to soil without acclimatization and produced viable plants.

IN VITRO PRODUCTION OF SET FROM ONION (Allium cepa L.) INFLORESCENCE.

Bulb formation in vitro is considered to be advantageous over shoot formation. Bulbs were farmed in vitro from onion inflorescence explants cultured in bulb induction medium composed of Murashige and Skoog (MS) medium supplemented with 120 g/l sucrose and 5 g/l activated charcoal under long day photoperiod. Bulbs were also induced in the same medium from shoots which were first regenerated from onion inflorescences in MS alone or MS containing either 4.4 uM benzyladenine or 0.005, 0.01, 0.05, 01 0.1 uM of thidiazurone. This system of in vitro bulb formation obviates shoot elongation, rooting, and acclimatization steps normally required when shoots are regenerated.