Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Impatiens”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Petaloidy and petal identity MADS-box genes in the balsaminoid genera Impatiens and Marcgravia.

Impatiens and Marcgravia have striking morphological innovations associated with the flowers. One of the sepals in Impatiens is spurred and petaloid, while in Marcgravia the petals are fused into a cap and nectary cups are associated with the inflorescence. Balsaminaceae (Impatiens) and Marcgraviaceae have surprisingly been shown to be closely related, since both belong to the balsaminoid clade of Ericales (basal asterids). However, several thorough morphological studies thus far have not revealed shared derived characters (synapomorphies) that support a close relationship between these families. In the balsaminoid clade, transitions from entirely green flowers to flowers with heterotopic petaloid organs can be observed. The primary role of class B genes in core eudicots is to specify the identity of petal and stamen floral organs. E-class genes, of which SEP3 is a representative, have been identified as redundant mediators that confer transcriptional activation potential on protein complexes that specify organ identity. Given the conserved function of organ-identity MADS-box genes in model plants, but the rapid molecular evolution in angiosperms, it remains controversial whether these genes have been involved in shaping floral diversity. We have identified a SEP3-like gene and a total of five class B genes from Impatiens hawkeri and Marcgravia umbellata and report their quantitative expression in the floral organs. In Impatiens, two AP3/DEF-like genes were identified with strongly divergent C-terminal domains, one truncated and one unusually long. Both genes show a gradual decrease in expression towards the outer perianth organs, but no GLO-like gene expression is observed in the petaloid sepal. Remarkably, SEP3-like gene expression in the Impatiens perianth is absent from the green sepals but present in the petaloid sepal and in the petals. Dimeric protein interactions of the cloned Impatiens genes were studied in yeast and by using gel retardation. In Marcgravia, strong overlapping class B gene expression is limited to the stamens, but a SEP3-like gene is strongly expressed in the Marcgravia nectary, indicating that both Impatiens and Marcgravia show heterotopic expression of a SEP3-like gene. We discuss several candidate mechanisms for heterotopic petaloidy involving modified gene expression and protein interaction of SEP3-like and class B genes.

Amino Acid Sequence↗

Interactions between Spinacia oleracea and Bradysia impatiens: a role for phytoecdysteroids.

Plant produced insect molting hormones, termed phytoecdysteroids (PEs), are thought to function as plant defenses against insects by acting as either feeding deterrents or through developmental disruption. In spinach (Spinacia oleracea), 20-hydroxyecdysone (20E) concentrations in the roots rapidly increase following root damage, root herbivory, or methyl jasmonate (MJ) applications. In this inducible system, we investigated the plant defense hypothesis by examining interactions of roots, 20E concentrations, and larvae of the dark-winged fungus gnat (Bradysia impatiens). Root herbivory by B. impatiens larvae resulted in a 4.0- to 6.6-fold increase in root 20E concentrations. In paired-choice tests, increases in dietary 20E stimulated B. impatiens feeding deterrency. B. impatiens larvae preferred control diets, low in 20E, to those constructed from induced roots and those amended with 20E (25 to 50 micro g/g wet mass). When confined to 20E-treated diets, concentrations as low as 5 micro g/g (wet mass) resulted in significantly reduced B. impatiens survivorship compared to controls. The induction of root 20E levels with MJ resulted in a 2.1-fold increase in 20E levels and a 50% reduction in B. impatiens larval establishment. In a paired-choice arena, untreated control roots were damaged significantly more by B. impatiens larvae than MJ-induced roots that contained 3-fold greater 20E levels. Based on dietary preference tests, the 20E concentrations present in the MJ-induced roots (28 micro g/g wet mass) were sufficient to explain this reduction in herbivory. Interactions between spinach roots and B. impatiens larvae demonstrate that PEs can act as inducible defenses and provide protection against insect herbivory.

Acetates↗

Bombus impatiens (Hymenoptera: Apidae): an alternative to Apis mellifera (Hymenoptera: Apidae) for lowbush blueberry pollination.

The pollination effectiveness of the commercially reared bumble bee Bombus impatiens Cresson, was compared in field studies to the honey bee, Apis mellifera L., for lowbush blueberry, Vaccinium angustifolium Ait. A preliminary study indicated that B. impatiens had potential as an alternative pollinator. In a 3-yr study, percentage fruit set, percentage harvested berries, berry weight, and seeds per berry were compared in blueberry fields stocked at 7.5 A. mellifera hives per hectare to 5, 7.5, or 10 B. impatiens colonies per hectare. Percentage of harvested berries (yield) was significantly higher in fields stocked with B. impatiens at 10 colonies per hectare. No other parameters measuring pollinator effectiveness were significantly different at 5, 7.5, or 10 colonies per hectare. Flower handling time was significantly faster for B. impatiens and it more frequently collected blueberry pollen. All parameters of pollinator effectiveness were similar for B. impatiens, A. mellifera, and native wild bees in a follow-up study. Overall, B. impatiens was a suitable alternative to A. mellifera.

Animals↗

LEAFY, TERMINAL FLOWER1 and AGAMOUS are functionally conserved but do not regulate terminal flowering and floral determinacy in Impatiens balsamina.

In Impatiens balsamina a lack of commitment of the meristem during floral development leads to the continuous requirement for a leaf-derived floral signal. In the absence of this signal the meristem reverts to leaf production. Current models for Arabidopsis state that LEAFY (LFY) is central to the integration of floral signals and regulates flowering partly via interactions with TERMINAL FLOWER1 (TFL1) and AGAMOUS (AG). Here we describe Impatiens homologues of LFY, TFL1 and AG (IbLFY, IbTFL1 and IbAG) that are highly conserved at a sequence level and demonstrate homologous functions when expressed ectopically in transgenic Arabidopsis. We relate the expression patterns of IbTFL1 and IbAG to the control of terminal flowering and floral determinacy in Impatiens. IbTFL1 is involved in controlling the phase of the axillary meristems and is expressed in axillary shoots and axillary meristems which produce inflorescences, but not in axillary flowers. It is not involved in maintaining the terminal meristem in either an inflorescence or indeterminate state. Terminal flowering in Impatiens appears therefore to be controlled by a pathway that uses a different integration system than that regulating the development of axillary flowers and branches. The pattern of ovule production in Impatiens requires the meristem to be maintained after the production of carpels. Consistent with this morphological feature IbAG appears to specify stamen and carpel identity, but is not sufficient to specify meristem determinacy in Impatiens.

AGAMOUS Protein, Arabidopsis↗

Comparison and examination of Bombus occidentalis and Bombus impatiens (Hymenoptera: Apidae) in tomato greenhouses.

Experiments were conducted in commercial tomato, Lycopersicon esculentum Miller (Solanaceae), greenhouses to compare the relative foraging effort of two bumble bee species, Bombus occidentalis Greene and Bombus impatiens Cresson, to examine interspecific competition between B. occidentalis and B. impatiens, and to determine whether bumble bee colonies grew to their full population potential in commercial tomato greenhouses. B. impatiens colonies had more brood and workers and made more foraging trips per hour than B. occidentalis colonies. However, B. impatiens returned to the colony without pollen loads and left their colonies without dropping off their pollen loads more frequently than B. occidentalis greenhouse colonies. Our data also suggest that the presence of B. impatiens had a detrimental effect on B. occidentalis populations. Furthermore, B. occidentalis colonies did not grow to their full population potential in tomato greenhouses, with fewer workers in greenhouse colonies than in colonies placed outside in a natural environment, or in colonies that were physically enclosed and protected from external mortality. Together, this study suggests that B. impatiens is a better pollinator than B. occidentalis. It also shows that unknown factors are limiting the size of B. occidentalis colonies in tomato greenhouses.

Agriculture↗

Immunomodulatory activity of the rhizomes of Impatiens pritzellii var. hupehensis on collagen-induced arthritis mice.

Impatiens pritzellii Hook. f. var. hupehensis Hook. f. (Balsaminaceae) has been well-known and widely used in China as an anti-rheumatoid arthritis (anti-RA) herb. In this present study, mice with collagen-induced arthritis (CIA) have been treated with the methanol (MeOH) extract (0.56, 1.12, 1.68 and 2.24 g/kg body weight) and the n-butanol (BuOH) fraction (0.13, 0.27, 0.40 and 0.53 g/kg body weight) of the rhizomes of Impatiens pritzellii orally for 3 weeks. The progression of CIA was evaluated by macroscopic scoring. Administration of the MeOH extract at dose of 1.12 g/kg and the BuOH fraction at 0.53 g/kg suppressed the development of CIA in mice significantly. The spleen and thymus indexes were measured and the levels of IgG, IL-10, INF-gamma and IL-18 in the serum of CIA mice were examined after the treatment of the MeOH extract (1.12 and 1.68 g/kg body weight) and the BuOH fraction (0.40 and 0.53 g/kg body weight). Administration of the MeOH extract and the BuOH fraction of Impatiens pritzellii decreased the spleen and thymus indexes, down-regulated the levels of IgG, INF-gamma, IL-18, and up-regulated the concentration of IL-10 in the serum of mice with CIA. From the results, it was concluded that administration of Impatiens pritzellii had obviously therapeutic effects on RA including immunomodulatory activity. Moreover, the BuOH fraction exerted the activity of anti-RA of Impatiens pritzellii.

1-Butanol↗

Abscission of Phaseolus and Impatiens Explants: Effects of Ionizing Radiation upon Endogenous Growth Regulators and de Novo Enzyme Synthesis.

Stem-petiole explants from the lower pulvinus of the primary leaves of Phaseolus vulgaris L. cv. Red Kidney and from Impatiens sultani Hook cv. Scarlet Baby were exposed to varying dosages of gamma-radiation. With bean, irradiation of 175 to 525 kiloroentgens (kR) significantly accelerated the onset of abscission with a maximum response at 175 to 280 kR. Higher dosages (beginning at 600-700 kR) usually prevented abscission. With Impatiens, 18 to 35 kR significantly accelerated both the onset of abscission and possibly the initial abscission rate; 350 kR cut the time to 100% abscission in half and substantially accelerated the initial abscission rate. Inhibition of abscission in Impatiens was not possible with the available dose rate (35 kR/hour).The accelerating effect of ionizing radiation was apparently due to primarily a reduction in auxin activity, thus accelerating the shift from the relatively ethylene-insensitive stage I to the ethylene-sensitive stage II. In vitro irradiation of exogenous auxin in agar substantially reduced the abscission-delaying effects of the auxin. The low dosage accelerating effects of the ionizing radiation were negated by exogenous auxin application, either prior to or following irradiation. With prior auxin application, a higher concentration of auxin was required to achieve the same delaying effects as with application following irradiation. Apparently due to this reduction in auxin activity, irradiation hastened sensitivity to exogenous ethylene.The accelerating effects of ionizing radiation may be secondarily due to increased levels of endogenous ethylene. With bean tissues, exposures of 262 through 1500 kR of gamma radiation increased the measurable levels of endogenous ethylene released into the ambient air within 2 or 3 days after irradiation.The results of actinomycin D treatment suggested that required de novo RNA synthesis occurred about 4 hours earlier in those Impatiens explants that had received 105 kR gamma radiation than in the nonirradiated controls.An increased mobilization of Ca from the abscission zone may be a contributing factor in the radiation-induced acceleration of abscission. For both bean and Impatiens, exogenous Ca inhibited abscission of irradiated and nonirradiated explants. In addition, a more concentrated Ca solution was required to inhibit abscission of irradiated bean explants, as compared to the nonirradiated controls.

Journal Article↗

Commercial bumble bee Bombus impatiens (Hymenoptera: Apidae) as a pollinator in lowbush blueberry (Ericale: Ericaceae) fields.

Here, we evaluate the potential of the bumble bee Bombus impatiens Cresson, obtained from commercial colonies, as a pollen vector for lowbush blueberry, Vaccinium augustifolium Aiton. We wanted to gain insight into the relationships between pollination by introduced bumble bees, the categories of seeds produced, and the weight and the maturity of the blueberries. The effect of B. impatiens foraging in blueberry stands was measured quantitatively through fruit set and seed set analysis. We created a density gradient of B. impatiens by clustering 72 small hives at the southern extremity of blueberry fields located in Girardville (49 degrees 00' N, 72 degrees 33' W), Quebec, Canada. Observers recorded plant and insect data in 52 plots of 1 by 10 m, distributed at distances ranging from 25 to 1,500 m from the hives. From these data, we evaluated the fruit set rate, the weight and maturity of the berries, and the number of seed structures per berry, including true seeds of large, medium, and small size, pseudo-seeds, and ovules. Positive correlations were found between the density of B. impatiens and fruit set as well as the number of large seeds per berry. Large seeds influenced the weight and maturity of berries. B. impatiens acted as a "near-nest central forager" and increased fruit set and seed production up to 100 and 150 m respectively, from the hives.

Animals↗

AFLP analysis of genetic variability in New Guinea impatiens.

New Guinea impatiens ( Impatiens hawkeri) is an economically important floral crop, however, little work has been conducted to further our understanding of the genetics of this crop. In this study, we used amplified fragment length polymorphism (AFLP) technology to investigate the level of polymorphism present among 41 commercial cultivars of New Guinea impatiens, study their genetic relatedness, and assess the genetic diversity in this material. An efficient DNA extraction protocol was developed, and a total of 48 EcoRI and MseI primer combinations were used for PCR amplification. Amplification products were then subjected to polyacrylamide gel electrophoresis. The AFLP analysis showed that all 41 cultivars generated between 73 and 130 scoreable polymorphic bands per primer combination. Gower's Genetic Dissimilarity estimates for the entire set of cultivars ranged between 0.940 and 0.488. A dendogram was generated from these dissimilarity data that revealed four groupings among these 41 cultivars. The implications of these results on genotypic variation, genetic relationships, and genetic diversity in New Guinea impatiens will be discussed.

DNA, Plant↗

Pollination ecology and pollination system of Impatiens reptans (Balsaminaceae) endemic to China.

BACKGROUND AND AIMS: China is one of the centres of geographical distribution of Impatiens L. Studies of the pollination ecology of this genus in China have, until now, been unreported. Impatiens reptans, a species endemic to China, was studied. The aims were to examine the pollination ecology and pollination system of this species, to compare its pollination ecology with other Impatiens species growing in Sumatra and Japan, and to discuss possible reasons for its limited distribution. METHODS: The pollination ecology of I. reptans was studied by carrying out continuous observations within three naturally growing populations. Its pollination system was studied using different pollination methods, marking and counting pollen grains, assessing pollen viability and observing pollinator behaviour. KEY RESULTS: The flowering phase of the protandrous I. reptans lasted for 89 d. The life span of an individual flower was 3.6 d. Primary pollinators were honey-bees and bumble-bees. Secondary pollinators were diurnal hawk moths and butterflies. Bombus briviceps and Bombus sp. were nectar gatherers. The mean nectar sugar concentration was 29.5 %, and the mean value of sucrose/glucose + fructose was 0.82. The proportion of seed set ranged from 0.857 to 0.873. Distances that seeds were ejected ranged from 0.58 to 1.17 m. Percentage seed germination under controlled conditions was 23.1. Pollen viability was highest on the day of anthesis and thereafter decreased. Ratios of pollen : ovules ranged from 958.8 to 970.6. CONCLUSIONS: Impatiens reptans reproduces by means of cross-pollination. Its dependence on a specialized habitat, a narrow environmental niche, a low percentage of seed germination, and habitat loss could be reasons for its limited distribution and endemism.

Animals↗

Mechanisms of derived unitegmy among Impatiens species.

Morphological transitions associated with ovule diversification provide unique opportunities for studies of developmental evolution. Here, we investigate the underlying mechanisms of one such transition, reduction in integument number, which has occurred several times among diverse angiosperms. In particular, reduction in integument number occurred early in the history of the asterids, a large clade comprising approximately one-third of all flowering plants. Unlike the vast majority of other eudicots, nearly all asterids have a single integument, with the only exceptions in the Ericales, a sister group to the other asterids. Impatiens, a genus of the Ericales, includes species with one integument, two integuments, or an apparently intermediate bifid integument. A comparison of the development of representative Impatiens species and analysis of the expression patterns of putative orthologs of the Arabidopsis thaliana ovule development gene INNER NO OUTER (INO) has enabled us to propose a mechanism responsible for morphological transitions between integument types in this group. We attribute transitions between each of the three integument morphologies to congenital fusion via a combination of variation in the location of subdermal growth beneath primordia and the merging of primordia. Evidence of multiple transitions in integument morphology among Impatiens species suggests that control of underlying developmental programs is relatively plastic and that changes in a small number of genes may have been responsible for the transitions. Our expression data also indicate that the role of INO in the outgrowth and abaxial-adaxial polarity of the outer integument has been conserved between two divergent angiosperms, the rosid Arabidopsis and the asterid Impatiens.

Arabidopsis↗

Transcription pattern of a FIM homologue in Impatiens during floral development and reversion.

Flowering and reversion in Impatiens are characterised by gradual transitions of organ identity and constitute a unique system for the molecular and physiological study of floral organogenesis. The authors have isolated an Impatiens homologue of the FIM gene of Antirrhinum (UFO in Arabidopsis), Imp-FIM, and analysed its expression in three states of the terminal meristem: vegetative, floral, and reverted. In floral meristems, Imp-FIM transcription is associated with petal identity, as in Antirrhinum and Arabidopsis, but this is achieved through a novel transcription pattern, characterised by a high level of transcript within petal primordia. This novel transcription pattern could contribute to the more diffuse boundaries between organ types in Impatiens. In vegetative meristems, Imp-FIM is expressed in the axils of leaf primordia which are arranged in a spiral. A similar pattern is observed in reverted meristems in which leaf primordia are initiated in a whorled arrangement. This result indicates that the maintenance of floral phyllotaxis is not associated with a specific pattern of Imp-FIM transcription. Transcription of Imp-FIM in a non-reverting line is no different from that in the reverting line. Therefore, the lack of floral commitment in the reverting line does not seem to be responsible for Imp-FIM transcription within petals. The novel transcription pattern in petals, together with features of Impatiens that are reminiscent of fim and ufo mutant phenotypes suggest an evolutionary divergence for Imp-FIM regulation in this species.

Amino Acid Sequence↗

Within-plant distribution of twospotted spider mites (Acari: Tetranychidae) on impatiens: development of a presence-absence sampling plan.

The twospotted spider mite, Tetranychus urticae Koch, is an important pest of impatiens, a floricultural crop of increasing economic importance in the United States. The large amount of foliage on individual impatiens plants, the small size of mites, and their ability to quickly build high populations make a reliable sampling method essential when developing a pest management program. In our study, we were particularly interested in using spider mite counts as a basis for releasing biological control agents. The within-plant distribution of mites was established in greenhouse experiments and these data were used to identify the sampling unit. Leaves were divided into three zones according to location on the plant: inner, intermediate, and other. On average, 40, 33, and 27% of the leaves belonged to the inner, intermediate, and other leaf zones, respectively. However, because 60% of the mites consistently were found on the intermediate leaves, intermediate leaves were chosen as the sampling unit. These results lead to the development of a presence-absence sampling method for T. urticae by using Taylor coefficients generic for this pest. The accuracy of this method was verified against an independent data set. By determining numerical or binomial sample sizes for consistently estimating twospotted spider mite populations, growers will now be able to determine the number of predatory mites that should be released to control twospotted spider mites on impatiens.

Animals↗

The induction and maintenance of flowering in Impatiens.

The mechanisms that establish the floral meristem are now becoming clearer, but the way in which flowering is maintained is less well understood. Impatiens balsamina provides a unique opportunity to address this question because reversion to vegetative growth can be obtained in a predictable way by transferring plants from inductive to non-inductive conditions. Following increasing amounts of induction, reversion takes place at progressively later stages of flower development. Partial flower induction and defoliation experiments show that a floral signal is produced in the cotyledon in response to inductive conditions and that this signal progressively diminishes after transfer to non-inductive conditions, during reversion. Therefore reversion in Impatiens is most likely due to the failure of leaves to become permanent sources of inductive signal in addition to the lack of meristem commitment to flowering. Analysis of the expression of the Impatiens homologues of the meristem identity genes floricaula and squamosa indicates that a change in floricaula transcription is not associated with the establishment or maintenance of the floral meristem in this species. Squamosa transcription is associated with floral development and petal initiation, and is maintained in existing petal or petaloid primordia even after the meristem has reverted. However, it is not expressed in the reverted meristem, in which leaves are initiated in whorled phyllotaxis and without axillary meristems, both characteristics usually associated with the floral meristem. These observations show that squamosa expression is not needed for the maintenance of these floral characters. The requirement for the production of the floral signal in the leaf during the process of flower development may reflect an additional function separate to that of squamosa activation; alternatively the signal may be required to ensure continued transcriptional activation in the meristem.

Amino Acid Sequence↗

Effects of oxybarbiturates on the germination behaviour of Impatiens bolstii pollen.

Swelling of and cytoplasmic streaming within the grain, germination pore expansion, and pollen tube emergence, in that order, constitute the normal germination pattern of Impatiens holstii pollen grains. This normal sequence of events becomes manifest when the pollen grains are placed on water-agar, barbituric acid-agar, and on barbital-agar media whereas this sequence of events is interfered with when the pollen grains are incubated on amytal-agar or on seconal-agar media. Evidence is presented which demonstrates that the normal sequence of events which make up the normal germination pattern of Impatiens holstii pollen grains can be separated from each other by varying the concentrations of the oxybarbiturates amytal and seconal used. Evidence is also presented which indicates that the actions of barbituric acid and the oxybarbiturates barbital, amytal, and seconal on Impatiens holstii pollen germination behaviour correlate well with certain aspects of the pharmacological literature concerning the actions of these organic compounds on the central nervous system (CNS).

Amobarbital↗

Extension growth of Impatiens glandulifera at low irradiance: importance of nitrate and potassium accumulation.

BACKGROUND AND AIMS: The summer annual Impatiens glandulifera can reach 3 m in height within deciduous woodland. The primary objective was to determine if NO(3)(-) accumulation, and hence its osmotic effect, is an important physiological mechanism allowing Impatiens to achieve substantial height under low irradiance. METHODS: Stem extension, concentrations of K(+) and NO(3)(-) in leaves and concentrations of K(+), NO(3)(-) and other inorganic anions, malate, sugars, total N and total osmoticum in stem were measured in I. glandulifera sampled at different irradiance levels in deciduous woodland and in a glasshouse. Also, the energetic costs, as absorbed photons, of generating osmolarity in stem cell vacuoles with KNO(3), K(2)malate or hexose sugar were determined. KEY RESULTS: Results were similar in the woodland and glasshouse. At 50-100 % relative irradiance (Ir; open ground PAR = 100 % Ir) and 2-10 % Ir, plant height increased from 7-14 cm to 130-154 cm in 64-67 d. Leaf and stem NO(3)(-) concentrations were negligible at 50-100 % Ir while K(+), malate(2-) and sugars, respectively, accounted for 33.2-50.1 %, 19.3-20.8 % and 2.0-2.6 % of total osmoticum in stems. At 2-10 % Ir, NO(3)(-) concentrations were four to eight times greater in stems than leaves. Here, NO(3)(-) constituted 26.7-34.3 % of the total osmotic concentration in the stem and NO(3)(-)-N constituted 69-81 % of total N in stem tissue. Also at 2-10 % Ir, K(+) comprised 44.9-45.9 % and malate plus sugars 2.2-3.1 % of total osmotic concentration. The energy cost of osmoticum as KNO(3) was calculated as less than half that of malate and less than one-seventh that for hexose. Further calculations suggest that use of KNO(3), K(2)malate or glucose as osmoticum at low irradiance would, respectively, cost approx. 7 %, 16 % and 50 % of the total construction cost of the stem. CONCLUSIONS: It is concluded that accumulation of NO(3)(-) in place of organic molecules in stems is an important mechanism allowing I. glandulifera to achieve substantial height at low irradiance.

Acclimatization↗

Floral meristem indeterminacy depends on flower position and is facilitated by acarpellate gynoecium development in Impatiens balsamina.

* Floral meristems are generally determinate. Termination of their activity varies with species, occurring after carpel or ovule development, depending on the placentation type. In terminal flowering Impatiens balsamina (cv. Dwarf Bush Flowered) some flowers exhibit meristem indeterminacy; they produce organs from the placenta after ovule development. * Here we provide a detailed description of gynoecium development in this line and explore the basis of the indeterminate nature of some of its floral meristems. * We find that the placenta is sometimes established without complete carpel fusion. Proliferative growth derives from meristematic remnants of the placenta and is more common in the terminal inflorescence. RNA in situ hybridization reveals that IbLFY (Impatiens LFY homologue) is expressed in all meristem states, even in proliferating meristems. Expression of IbAG in axillary flowers is as expected in the meristem, stamens and carpels but absent from the proliferating meristem. * We conclude that I. balsamina has cauline placentation. Incomplete suppression of inflorescence identity in flowers of the terminal inflorescence leads to floral meristem proliferation after ovule development in this species.

Cell Differentiation↗

Quantitative determination of naphthoquinones of Impatiens species.

A convenient and reliable reversed phase-HPLC method has been developed and validated for the quantitative determination of naphthoquinones present in the aerial parts of Impatiens glandulifera (Balsaminaceae) during two growing seasons (May to August 1998 and June to October 1999). Maximal content (0.8-1.1%) of 2-hydroxy-1,4-naphthoquinone and its 2-methylated derivative was observed in flowers collected between July and August. The procedure was applied to compare the pigment content in three other species of Impatiens but showed 2.5-37 times lower levels than those found in I. glandulifera.

Balsaminaceae↗