Two Shades of Grey: Effect of Temperature on Seed Germination of the Escaping Ornamental Species Lychnis Coronaria and Stachys Byzantina

This paper describes germination and cytological variability in two popular ornamental and potentially invasive species, lamb’s ear Stachys byzantina and rose campion Lychnis coronaria. Both xerophytic species have the potential to invade natural habitats across Europe and create viable naturalised populations, with subsequent impacts on native vegetation. To assess the species’ invasiveness, seeds were collected from naturalised populations and germination rate recorded under different temperature regimes. Flow cytometry, used to record cytological variability, indicated that all populations of both species were cytologically homogeneous. Germination success, a key spreading factor in both species, was significantly influenced by temperature, with final germination of L. coronaria being extremely high at temperatures > 15/10 °C (98.5%) and extremely low at temperatures < 10/5 °C (2.9%). In comparison, final germination in S. byzantina highest at 22/15 °C (55.6%), reducing to 40.3% at 15/10 °C and just 0.3% at temperatures < 10/5 °C. No significant differences in germination rate were observed between escaping and non-escaping populations, though there were differences between particular populations. Our results indicate germination temperature limits between species consistent with sizes of primary distribution and distance between primary and secondary distribution borders. However, the observed germination rates allow for successful generative reproduction of both species over their secondary distribution areas, suggesting that these species are likely to become invasive species of European grasslands soon.

Evaluating Importation of Aquatic Ornamental Species for Biosecurity Purposes

The aquatic ornamental species (AOS) trade is a significant pathway for the introduction and establishment of non-indigenous species into aquatic environments. The likelihood of such occurrences is expected to increase worldwide as industry growth continues and warmer conditions emerge under future climate scenarios. This study used recent (2015 – 2019) New Zealand importation data to determine the composition, diversity, abundance, and arrival frequency of AOS. Our analysis revealed that ca. 300,000 aquatic ornamental individuals are imported annually to New Zealand, with freshwater fish comprising 98% of import quantities. Despite the relatively small market size, the estimated AOS diversity of 865 taxa (89 and 9.5% identified to species and genus level, respectively) is comparable to larger markets with ∼60% of taxa being of marine origin. Species (n = 20) for further investigation were prioritized based on quantity and frequency of import. These prioritized AOS were exclusively tropical and subtropical freshwater fish and align with the most frequently imported AOS globally, including the top three: neon tetra (Paracheirodon innesi), guppy (Poecilia reticulata), and tiger barb (Puntigrus tetrazona). Species distribution modeling of the 20 prioritized AOS predicted that 13 species are suitable for New Zealand’s current climate conditions, most notably sucker-belly loach (Pseudogastromyzon myersi), white cloud mountain minnow (Tanichthys albonubes), and golden otocinclus (Macrotocinclus affinis). Potential changes in habitat suitability were predicted under future climate scenarios, with largest increases (29%) for Po. reticulata. The described approach provides an adaptable framework to assess establishment likelihood of imported AOS to inform regulatory decision making.

STATUS DE CONHECIMENTO DO ACARI-ZEBRA Hypancistrus zebra Isbrücker & Nijssen, 1991 (SILURIFORMES, LORICARIIDAE)

The present work aimed to review the literature on studies carried out on the “acari-zebra” (Hypancistrus zebra Isbrücker & Nijssen, 1991). The data search was performed in four scientific databases (Capes journals, Google Scholar, Scielo, ScienceDirect and Web of Science Core Collection), using the scientific and common name of the species as keywords. Articles were selected when they had any of the keywords used in the title or abstract, excluding works from gray literature. After selecting the articles in the scientific databases, a careful reading was carried out in order to characterize the taxonomy, biology, ecology, fisheries and conservation status of H. zebra. The “acari-zebra” is an ornamental species endemic to the Xingu River basin, which has a high economic value internationally. It was recently added to the endangered species list due to overfishing of the species. Literature on H. zebra proved to be very scarce, with only basic information on taxonomy, fisheries, reproductive aspects and studies aimed at cultivation. Among the studies to be carried out, we highlight the characterization of growth and reproductive dynamics. These studies will enable a better understanding of the biology of the species and will contribute to a definition of the technological package of reproduction in captivity.

Overcoming dormancy in seeds of Dietes bicolor (Steud.) Sweet ex Klatt

Seminiferous propagation of Dietes bicolor is hindered by the probable physical and/or morphophysiological dormancy. The objective was to analyze the efficacy of different methods of overcoming dormancy in D. bicolor seeds to determine a possible pre-germination treatment for the species. Two experiments were conducted: (I) Evaluation of the breaking of physical dormancy, in which the treatments of mechanical scarification were carried using sandpaper #100; chemical scarification with sulfuric acid (H2SO4) for 5 and 10 minutes and immersion in hot water (70 ºC), also, for 5 and 10 minutes, were evaluated. The intact seed was considered a control. (II) Evaluation of morphophysiological dormancy, in which the seeds were submitted to combined treatments of stratification of hot temperature (20-35 °C) and/or cold temperature (9 ºC), distributed in periods of 0, 1, and 2 weeks, totalizing 9 treatments. In both experiments, germination percentage (G), germination speed index (GSI), and first count (FC) were determined, using a randomized block design, and evaluated by the Scott-Knott test at 1% and Dunnett’s test at 5%. The use of H2SO4 10 minutes induced 42% germination, 0.52 GSI, and 18% FC, but only FC was significantly different from the control. In the second trial, the treatment that spent only two weeks in hot temperatures (20-35 ºC) showed the highest germination (30%), compared to the control (G = 22%). These results provide relevant information for understanding the physiology of D. bicolor germination, in addition to contributing to the optimization of pre-germination practices for this important ornamental species.

Problems of biotic and landscape diversity conservation in the Ukrainian Carpathians highlands

Introduction. The highlands of the Ukrainian Carpathians belong to the territories with the highest concentration of rare species and coenotic diversity in Ukraine. Due to highland ecosystem transformation, a large number of populations and communities of rare species are under the threat of degradation and elimination. Climate change. At present, effective growth and development of plants begins 2–3 weeks earlier compared to the 1980–90s. Sharp seasonal distribution of precipitation causes negative changes in the highland water-body hydrology regime affecting freshwater populations of plankton crustaceans and amphibians. Demutative successions. During the first 10–20 years of the succession its influence on the structure and vitality of the majority of rare species populations is mostly positive, but 30–40 year-long demutations usually cause negative dynamics. Overgro­wing results in the simplification of spatial structure and fragmentation, as well as decreasing of population density, disappearing of rare species from the community structure. Active protection measures should be locally implemented in protected territories: traditional type of grazing, mowing, and shrub or tree cutting in the cases of protection of extremely rare phytocoenoses and populations. Anthropogenic impact. Intensive recreation pressure causes digressive changes in numerous communities, which are located along the popular tourist paths to the glacial lakes, mountain summits etc. Unfortunately, the systematic violation of the protection regime in the highland zone of the Ukrainian Carpathians is obvious nowadays. Gathering medicinal and ornamental species poses a serious threat. Uncontrolled increase in the number of recreants in the highland areas for the last 5 years has destroyed its aquatic ecosystems more than in the previous 30–40 years. Usage of vehicles for recreation purposes (4×4, quads and motorcycles) refers to significant destructive factors for highland ecosystems. Protection measures. Population conservation and revival of communities is usually possible under the condition of moderate and short-term anthropogenic pressure. The visiting regime of the most popular highland sites must be put under control immediately, while mass ascensions must be completely forbidden.

Monitoring Optical Tool to Determine the Chlorophyll Concentration in Ornamental Plants

The accurate estimation of leaf photosynthetic pigments concentration is crucial to check the plant´s health. Traditional methods of measuring photosynthetic pigments involve complex procedures of solvent extraction followed by spectrophotometric determinations. Portable plant instruments such as Soil Plant Analysis Development (SPAD) meters can facilitate this task for the speed and simplicity of the measures. The relationship between chlorophyll index obtained by SPAD-502 and pigment concentration in several ornamental species can help in the management of ornamental plant production. Two trials have been carried out in two different growing seasons (spring and summer) and facilities (greenhouse and open air), involving 30 ornamental species. There was a high linear relationship between concentrations of Chla and Chlb, as well as between Chlt and Ct in different species studied under greenhouse and open field conditions. The ratio between Chla and Chlb was higher at open field conditions and similar between Chlt and Ct. There was also a good relationship between Chlorophyll index and Chlt under both growing conditions, as well as between Chlorophyll index and Ct under greenhouse conditions. However, linear relationships with different slopes were observed for groups of species at open field conditions.

Standardization of Growing Media for Ornamental Plant Species Grown in A Vertical Garden System in Assam

An experiment was carried out with an aim to standardize the growing media for five ornamental plant species in a vertical garden system in the Department of Horticulture, Assam Agricultural University, Jorhat, Assam. The experiment was laid out in a completely randomized block design with three replications, comprising of five ornamental plant species grown in five different media compositions. The experiment was conducted to study the influence of soil, vermicompost, cocopeat and sand on the plant species in the vertical garden system. The five different media compositions under study were M1: soil + cocopeat + vermicompost + sand (3 : 0.25 : 1 : 1.5), M2: soil + cocopeat + vermicompost + sand (2.5 : 0.5 : 1.5 : 1.25), M3: soil + cocopeat + vermicompost + sand (2 : 0.75 : 2 : 1), M4: soil + cocopeat + vermicompost + sand (1.5 : 1 : 2.5 : 0.75) and M5: Soil. The ornamental species selected were: S1 : Philodendron Ceylon (Philodendron erubescens ‘Gold’ K. Koch), S2: Spider Plant (Chlorophytum comosum Variegatum (Thunb.)), S3: Fern (Nephrolepis exaltata (L.) Schott), S4: Moses-in-the-cradle (Rhoeo discolor Sw. (syn. Tradescantia spathacea)) and S5: Baby Doll Cordyline (Cordyline compacta Purple (L.)). Among the five growing media compositions used, medium M3: soil + cocopeat + vermicompost + sand (2 : 0.75 : 2 : 1) performed better in terms of all the growth parameters recorded in the five plants species in the vertical garden system.

Spring phenology of some ornamental species, as an indicator of temperature increase in the urban climate area

The aim of this study is to provide information on the phenology of urban spring season, of some species of ornamental trees and shrubs, in the light of climate changes occurred over the recent decades. Ten species of ornamental shrubs and trees cultivated in two areas of a town located in southwestern Romania were studied. It was found that the spring season phenology of the studied species is dependent on the climatic year, in recording differences between the number of days from November 1 and the beginning of each spring phenophase, both from one species to another and from one climatic year to another, and also from one area to another; the spring phenology starting earlier in the urban area regardless of the species and the climatic year. Higher temperatures, rising from one year to another, are speeding-up the onset and development of spring phenology, regardless of species, and the urban climate through the effect of urban heat island leads to even earlier onset of spring phenophases and shortening of the growing season, so that by phenological differences existing within the species from one climatic year to another and from one climatic zone to another, spring season phenology can be considered an indicator of temperature rise.

Hitchhiking Exotic Clam: Dreissena polymorpha (Pallas, 1771) Transported via the Ornamental Plant Trade

Ornamental aquaculture is one of the main sources of non-native species worldwide. Unintentionally transported “hitchhiking” organisms have been previously recorded; although most of these species are transported from tropical regions, here we report on the first accidental transport of the zebra mussel (Dreissena polymorpha) in a shipment of ornamental Aegagropila linnaei (Chlorophyta) from Russia to the Czech Republic. This invasive mussel is listed on the national blacklist of alien species in the Czech Republic and can be easily released in outdoor garden ponds together with A. linnaei. Since the Czech Republic is known to be a gateway for aquatic ornamental species from a European perspective, re-export to other European countries is also possible. Thus, the spread of D. polymorpha via this pathway cannot be excluded. This finding should be of importance to conservationists, traders, decision-makers and other stakeholders.