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Petr Pysek - One of the best experts on this subject based on the ideXlab platform.
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habitat requirements short term population dynamics and coexistence of native and invasive Impatiens species a field study
Biological Invasions, 2014Co-Authors: Jan Cuda, Hana Skalova, Zdeněk Janovský, Petr PysekAbstract:The genus Impatiens (Balsaminaceae) includes three widespread species in the Czech Republic, central Europe: the native I. noli-tangere, and two invasive species, I. parviflora and I. glandulifera, differing in the dynamics of invasion. They all occur in similar habitats and share basic life-history characteristics, which make them a suitable model for studying species traits associated with invasiveness. In this study we investigated differences in habitat requirements of these Impatiens species, their coexistence and short-term population dynamics in the field. We established 84 1 × 1 m permanent plots in five localities where all three species co-occurred. In each plot vascular plant species were determined, their cover estimated and all individuals of Impatiens species counted. Site characteristics including tree canopy cover, soil moisture, nitrogen and carbon content, and slope were measured directly. Nutrients, light, humidity and soil reaction were estimated using Ellenberg indicator values. The presence of I. noli-tangere was strongly correlated with high soil moisture, that of I. parviflora with high tree canopy cover and low soil moisture. Impatiens glandulifera exhibited a unimodal response to tree canopy cover, avoiding both very shaded and fully open sites. The current-year abundances of all species were negatively related to those of congeneric species. These results suggest that the coexistence of Impatiens species in the same habitat is due to microsite differentiation. Further spread of I. glandulifera to new habitats, and reduction of the native I. noli-tangere niche, can be expected in areas where the latter species co-occurs with competitively strong invasive congeners.
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germination dynamics and seedling frost resistance of invasive and native Impatiens species reflect local climatic conditions
Perspectives in Plant Ecology Evolution and Systematics, 2011Co-Authors: Hana Skalova, Petr Pysek, Lenka MoravcovaAbstract:Abstract Invasion of some alien plants is considered to be associated with inter-population differentiation and adaptations to local conditions. To obtain an insight into these processes it is convenient to compare invasive plants with their native congeners. The intra-specific differentiation during invasion was studied using four Impatiens (Balsaminaceae) species in Central Europe: native Impatiens noli-tangere and three aliens (highly invasive Impatiens glandulifera , less invasive Impatiens parviflora and potentially invasive Impatiens capensis ). Differentiation in traits important for the establishment (germination; seedling emergence; seedling frost resistance) was measured in a laboratory and an experimental garden using seed collected from five natural populations of each species. Frost resistance of I. capensis , currently invasive in Western Europe, was within the scope of other congeners and it does not seem to be a barrier to spread of the species into Central Europe. Among-population differences were found within all species except I. capensis . In I. noli-tangere , I. glandulifera and I. parviflora the differences were related to the climatic characteristics in early spring at the source localities, which indicates that individuals may be adapted to local conditions. The differences found between the populations of I. noli-tangere , I. glandulifera and I. parviflora are likely to reflect the frost sensitivity of the species. In the highly frost-sensitive I. parviflora differentiation was found both in germination and frost resistance of individual populations. In I. glandulifera the differences among populations in frost sensitivity depended on temperature at the seed source and corresponded to the pattern of emergence of seedlings in the garden. In the native I. noli-tangere , the differences among populations in the time of germination depended on temperature at the seed-source locality. Since local adaptations were indicated both in native and invasive species studied, they are unlikely to provide the invasive Impatiens species with an advantage against the native congener, at least in terms of the traits investigated.
Erik Smets - One of the best experts on this subject based on the ideXlab platform.
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Palynology of African Impatiens (Balsaminaceae)
Palynology, 2018Co-Authors: Steven B. Janssens, Erik Smets, Stefan Vinckier, Katrien Bosselaers, Suzy HuysmansAbstract:The pollen morphology of 63 African Impatiens species (Balsaminaceae) is studied using scanning electron microscopy. In addition, the pollen wall structure of five African Impatiens species was investigated with transmission electron microscopy. Pollen of African balsams is medium to large in size. Oblate Impatiens pollen is most common yet peroblate and suboblate pollen are also well represented. African pollen of the genus Impatiens is mainly circular, rectangular or elliptic. Reticulate sexine ornamentation is characteristic for most of the species investigated. Both homobrochate and heterobrochate pollen is present within the genus. Occasionally, the lumina are not entirely demarcated by muri, resulting in coalescence between adjacent lumina. The muri vary from slender with a tapering top edge, to slender with a rounded edge, to broad, more or less flattened muri. The tectal muri are always supported by two or three rows of short and massive columellae. Orbicules are absent in all species investigated. Observations of the pollen wall stratification show that pollen of African Impatiens consists of a thin foot layer, a lamellated endexine (characterized by remnants of the white lines) and a one-layered intine. Foot layer and endexine are slightly intermingled and therefore sometimes difficult to distinguish from each other.
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Three new species of Impatiens (Balsaminaceae) from Myanmar
Phytotaxa, 2018Co-Authors: Saroj Ruchisansakun, Piyakaset Suksathan, Timotheüs Van Der Niet, Saw Lwin, Erik Smets, Steven B. JanssensAbstract:Three new species of Impatiens (Balsaminaceae) from Myanmar are here described: I. decurva Ruchis. & S.B. Janssens , I. hartnolliae Hook. f. ex Ruchis. & Suksathan, and I. oblongata Ruchis. &Van der Niet. The 5-lobed short fusiform fruit of all three species suggests that they are members of subgen. Impatiens sect. Uniflorae Hook. f. & Thomson. For I. decurva and I. oblongata , subgenus membership was corroborated by phylogenetic analyses of a combined dataset of nuclear ITS and plastid atpB-rbcL intergenic spacer DNA sequences. This was not possible for I. hartnolliae , which is only known from a single herbarium specimen.
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rapid radiation of Impatiens balsaminaceae during pliocene and pleistocene result of a global climate change
Molecular Phylogenetics and Evolution, 2009Co-Authors: Steven Janssens, Erik Smets, Eric B Knox, Suzy Huysmans, Vincent S F T MerckxAbstract:Abstract Impatiens comprises more than 1000 species and is one of the largest genera of flowering plants. The genus has a subcosmopolitan distribution, yet most of its evolutionary history is unknown. Diversification analyses, divergence time estimates and historical biogeography, illustrated that the extant species of Impatiens originated in Southwest China and started to diversify in the Early Miocene. Until the Early Pliocene, the net diversification rate within the genus was fairly slow. Since that time, however, approximately 80% of all Impatiens lineages have originated. This period of rapid diversification coincides with the global cooling of the Earth’s climate and subsequent glacial oscillations. Without this accelerated diversification rate, Impatiens would only have contained 1/5th of its current number of species, thereby indicating the rapid radiation of the genus.
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phylogenetic utility of the ap3 def k domain and its molecular evolution in Impatiens balsaminaceae
Molecular Phylogenetics and Evolution, 2007Co-Authors: Steven Janssens, Erik Smets, Koen Geuten, Yongming Yuan, Yi Song, Tom ViaeneAbstract:APETALA3 (AP3)/DEFICIENS (DEF) is a MADS-box transcription factor that is involved in establishing the identity of petal and stamen floral organs. The AP3/DEF gene lineage has been extensively examined throughout the angiosperms in order to better understand its role in floral diversity and evolution. As a result, a large number of cloned AP3/DEF orthologues are available, which can be used for the design of taxon specific primers for phylogeny reconstruction of close relatives of the group of interest. Following this reasoning, we investigated the phylogenetic utility of the two AP3/DEF paralogues (ImpDEF1 and ImpDEF2) that were recently identified in the genus Impatiens (Balsaminaceae). K-domain introns 4 and 5 of both AP3/DEF duplicates were amplified and sequenced for 59 Impatiens species. Phylogenetic analyses of the separated and combined ImpDEF1 and ImpDEF2 data sets result in highly congruent topologies with the previously obtained chloroplast atpB-rbcL data set. Combination of chloroplast and nuclear matrices results in a well-supported evolutionary hypothesis of Impatiens. Our results show that introns 4 and 5 in AP3/DEF-like genes are a valuable source of characters for phylogenetic studies at the infrageneric level.
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phylogenetics of Impatiens and hydrocera balsaminaceae using chloroplast atpb rbcl spacer sequences
Various articles, 2006Co-Authors: Steven B. Janssens, Koen Geuten, Yongming Yuan, Yi Song, Philippe Kupfer, Erik SmetsAbstract:Balsaminaceae are a morphologically diverse family with ca. 1,000 representatives that are mainly distributed in the Old World tropics and subtropics. To understand the relationships of its members, we obtained chloroplast atpB-rbcL sequences from 86 species of Balsaminaceae and five outgroups. Phylogenetic reconstructions using parsimony and Bayesian approaches provide a well-resolved phylogeny in which the sister group relationship between Impatiens and Hydrocera is confirmed. The overall topology of Impatiens is strongly supported and is geographically structured. Impatiens likely originated in South China from which it colonized the adjacent regions and afterwards dispersed into North America, Africa, India, the Southeast Asian peninsula, and the Himalayan region.
Shengxiang Yu - One of the best experts on this subject based on the ideXlab platform.
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Impatiens maculifera sp nov balsaminaceae yunnan china
Nordic Journal of Botany, 2019Co-Authors: Gadagkar R Sudhindra, Hong-ping Deng, Xinlei Zhao, Shengxiang YuAbstract:Impatiens (Balsaminaceae) is a notoriously difficult genus to study for reasons that include small, remote and endemic areas of occurrence, and difficulty in obtaining well‐dried herbarium specimens and separating and reconstructing floral parts from available dried specimens. Impatiens has also been notoriously difficult when it comes to phylogenetic resolution at the infrageneric level, but a new system with two subgenera (Impatiens and Clavicarpa) was recently proposed by Yu et al. and it has made it easier to classify newly discovered species. Impatiens maculifera, a new species of Balsaminaceae from Malipo County, Yunnan, China described here, is similar to I. parvisepala S.X. Yu & Y.T. Hou in having racemose inflorescences, four lateral sepals, clavate capsules and ellipsoid seeds, but differs in having leaves narrowly oval or with elliptic–lanceolate blades (versus obovate or obovate–lanceolate), obvious petioles (versus leaves subsessile), racemose inflorescence with 8–12 flowers (versus 6–8 flowers), flowers greenish yellow (versus yellow), lateral united petals and lower sepal with dense red spots (versus red spots absent), and dorsal petal with apparent stalk at base (versus unapparent stalk). Morphological characters and molecular phylogenetic analyses of DNA sequences from both nuclear ribosomal and plastid genes show that the new species differs distinctively from I. parvisepala. Furthermore, I. maculifera is distinguished from other Impatiens species based on morphological, micromorphological and palynological evidence, and molecular data.
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phylogeny of Impatiens balsaminaceae integrating molecular and morphological evidence into a new classification
Cladistics, 2016Co-Authors: Shengxiang Yu, Steven B. Janssens, Magnus Liden, Wei WangAbstract:Impatiens L. is one of the largest angiosperm genera, containing over 1000 species, and is notorious for its taxonomic difficulty. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total evidence approach. Forty-six morphological characters, mainly obtained from our own investigations, are combined with sequence data from three genetic regions, including nuclear ribosomal ITS and plastid atpB-rbcL and trnL-F. We include 150 Impatiens species representing all clades recovered by previous phylogenetic analyses as well as three outgroups. Maximum-parsimony and Bayesian inference methods were used to infer phylogenetic relationships. Our analyses concur with previous studies, but in most cases provide stronger support. Impatiens splits into two major clades. For the first time, we report that species with three-colpate pollen and four carpels form a monophyletic group (clade I). Within clade II, seven well-supported subclades are recognized. Within this phylogenetic framework, character evolution is reconstructed, and diagnostic morphological characters for different clades and subclades are identified and discussed. Based on both morphological and molecular evidence, a new classification outline is presented, in which Impatiens is divided into two subgenera, subgen. Clavicarpa and subgen. Impatiens; the latter is further subdivided into seven sections. © The Willi Hennig Society 2015.
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Impatiens pterocaulis sp nov balsaminaceae from guangxi china
Nordic Journal of Botany, 2014Co-Authors: Lirong Zhang, Zhixiang Zhang, Rui Meng, Shengxiang YuAbstract:Impatiens pterocaulis S. X. Yu et L. R. Zhang, a new species of the Balsaminaceae from Yancha, Longlin, Guangxi Region, is described and illustrated. This species is similar to I. wilsonii in having nearly white flowers, 4 lateral sepals and a racememos inflorescence, but differs by having winged stems, very short-spurred lower sepal, yellowish flowers and an acuminate dorsal petal apex. Pollen characters and leaf epidermal micro-characters of these two species were studied, and the results support that the two species should be kept separate. The genus Impatiens L. belongs to the family Balsaminaceae, which contains two currently recognized genera; the small Hydrocera and the prolific Impatiens, of which the latter contains about 850 species (Grey-Wilson 1980, Fischer 2004). The genus Impatiens was first described by Linnaeus (1753), and is primarily an Old World genus, distributed throughout much of tropical Africa, India, southwest Asia, southern China and Japan. A few species reach the north temperate zone of Europe, Russia and China as well as North America (Grey-Wilson 1980).
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floral development in Impatiens chishuiensis balsaminaceae formation of two well developed anterolateral sepals and four carpels
Plant Systematics and Evolution, 2010Co-Authors: Shengxiang Yu, X R Zhou, G F Xu, L. Meng, H Y BiAbstract:Impatiens is a highly diversified genus with remarkable zygomorphic flowers. Floral ontogeny of three species of Impatiens has recently been studied, which suggested that, during the course of evolution, the anterolateral sepals become reduced and that these rudimentary sepals fuse postgenitally or congenitally with the anterior petal. All three belong to the majority type with five carpels and no mature anterolateral sepals. However, a few species of Impatiens have four carpels and two well-developed mature anterolateral sepals, and their floral development has never been examined. From a comparative-ontogenetic viewpoint, we explore the mechanism of formation of well-developed anterolateral sepals and four carpels in I. chishuiensis with five sepals and four carpels. The results show that, if anterolateral sepals are present, their early development statuses will likely influence whether or not the sepals can fully develop later, and that the initiation and development of five stamens have an effect on the shapes of floral apexes, eventually resulting in congenital fusion of two adaxial carpels. Furthermore, we discuss the systematic and evolutional value of floral early development data.
Hana Skalova - One of the best experts on this subject based on the ideXlab platform.
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habitat requirements short term population dynamics and coexistence of native and invasive Impatiens species a field study
Biological Invasions, 2014Co-Authors: Jan Cuda, Hana Skalova, Zdeněk Janovský, Petr PysekAbstract:The genus Impatiens (Balsaminaceae) includes three widespread species in the Czech Republic, central Europe: the native I. noli-tangere, and two invasive species, I. parviflora and I. glandulifera, differing in the dynamics of invasion. They all occur in similar habitats and share basic life-history characteristics, which make them a suitable model for studying species traits associated with invasiveness. In this study we investigated differences in habitat requirements of these Impatiens species, their coexistence and short-term population dynamics in the field. We established 84 1 × 1 m permanent plots in five localities where all three species co-occurred. In each plot vascular plant species were determined, their cover estimated and all individuals of Impatiens species counted. Site characteristics including tree canopy cover, soil moisture, nitrogen and carbon content, and slope were measured directly. Nutrients, light, humidity and soil reaction were estimated using Ellenberg indicator values. The presence of I. noli-tangere was strongly correlated with high soil moisture, that of I. parviflora with high tree canopy cover and low soil moisture. Impatiens glandulifera exhibited a unimodal response to tree canopy cover, avoiding both very shaded and fully open sites. The current-year abundances of all species were negatively related to those of congeneric species. These results suggest that the coexistence of Impatiens species in the same habitat is due to microsite differentiation. Further spread of I. glandulifera to new habitats, and reduction of the native I. noli-tangere niche, can be expected in areas where the latter species co-occurs with competitively strong invasive congeners.
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germination dynamics and seedling frost resistance of invasive and native Impatiens species reflect local climatic conditions
Perspectives in Plant Ecology Evolution and Systematics, 2011Co-Authors: Hana Skalova, Petr Pysek, Lenka MoravcovaAbstract:Abstract Invasion of some alien plants is considered to be associated with inter-population differentiation and adaptations to local conditions. To obtain an insight into these processes it is convenient to compare invasive plants with their native congeners. The intra-specific differentiation during invasion was studied using four Impatiens (Balsaminaceae) species in Central Europe: native Impatiens noli-tangere and three aliens (highly invasive Impatiens glandulifera , less invasive Impatiens parviflora and potentially invasive Impatiens capensis ). Differentiation in traits important for the establishment (germination; seedling emergence; seedling frost resistance) was measured in a laboratory and an experimental garden using seed collected from five natural populations of each species. Frost resistance of I. capensis , currently invasive in Western Europe, was within the scope of other congeners and it does not seem to be a barrier to spread of the species into Central Europe. Among-population differences were found within all species except I. capensis . In I. noli-tangere , I. glandulifera and I. parviflora the differences were related to the climatic characteristics in early spring at the source localities, which indicates that individuals may be adapted to local conditions. The differences found between the populations of I. noli-tangere , I. glandulifera and I. parviflora are likely to reflect the frost sensitivity of the species. In the highly frost-sensitive I. parviflora differentiation was found both in germination and frost resistance of individual populations. In I. glandulifera the differences among populations in frost sensitivity depended on temperature at the seed source and corresponded to the pattern of emergence of seedlings in the garden. In the native I. noli-tangere , the differences among populations in the time of germination depended on temperature at the seed-source locality. Since local adaptations were indicated both in native and invasive species studied, they are unlikely to provide the invasive Impatiens species with an advantage against the native congener, at least in terms of the traits investigated.
Brian A Nault - One of the best experts on this subject based on the ideXlab platform.
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pollination services provided by bees in pumpkin fields supplemented with either apis mellifera or bombus Impatiens or not supplemented
PLOS ONE, 2013Co-Authors: Jessica D Petersen, Stephen Reiners, Brian A NaultAbstract:Pollinators provide an important service in many crops. Managed honey bees (Apis mellifera L.) are used to supplement pollination services provided by wild bees with the assumption that they will enhance pollination, fruit set and crop yield beyond the levels provided by the wild bees. Recent declines in managed honey bee populations have stimulated interest in finding alternative managed pollinators to service crops. In the eastern U.S., managed hives of the native common eastern bumble bee (Bombus Impatiens Cresson) may be an excellent choice. To examine this issue, a comprehensive 2-yr study was conducted to compare fruit yield and bee visits to flowers in pumpkin (Cucurbita pepo L.) fields that were either supplemented with A. mellifera hives, B. Impatiens hives or were not supplemented. We compared pumpkin yield, A. mellifera flower visitation frequency and B. Impatiens flower visitation frequency between treatments. Results indicated that supplementing pumpkin fields with either A. mellifera or B. Impatiens hives did not increase their visitation to pumpkin flowers or fruit yield compared with those that were not supplemented. Next, the relationship between frequency of pumpkin flower visitation by the most prominent bee species (Peponapis pruinosa (Say), B. Impatiens and A. mellifera) and fruit yield was determined across all pumpkin fields sampled. Fruit yield increased as the frequency of flower visits by A. mellifera and B. Impatiens increased in 2011 and 2012, respectively. These results suggest that supplementation with managed bees may not improve pumpkin production and that A. mellifera and B. Impatiens are important pollinators of pumpkin in our system.
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performance of apis mellifera bombus Impatiens and peponapis pruinosa hymenoptera apidae as pollinators of pumpkin
Journal of Economic Entomology, 2011Co-Authors: Derek R Artz, Brian A NaultAbstract:ABSTRACT Pollination services of pumpkin, Cucurbita pepo L., provided by the European honey bee, Apis mellifera L., were compared with two native bee species, the common eastern bumble bee, Bombus Impatiens (Cresson), and Peponapis pruinosa Say, in New York from 2008 to 2010. Performance of each species was determined by comparing single-visit pollen deposition, percentage of visits that contacted the stigma, flower-handling time, fruit and seed set, and fruit weight per number of visits. Fruit yield from small fields (0.6 ha) supplemented with commercial B. Impatiens colonies was compared with yield from those not supplemented. A. mellifera spent nearly 2 and 3 times longer foraging on each pistillate flower compared with B. Impatiens and P. pruinosa, respectively. A. mellifera also visited pistillate flowers 10–20 times more frequently than B. Impatiens and P. pruinosa, respectively. Yet, B. Impatiens deposited 3 times more pollen grains per stigma and contacted stigmas significantly more often than eit...
