Summer-flowering Plants Research Articles

Biological features of flowering of the genetic collection of plants of the family Onagraceae Juss. in the forest-steppe conditions of Western Siberia

Data on the timing of the onset of phenological phases and the duration of the flowering period of the genetic collection of annual flowering plants from three sections of the family Onagraceae Juss. are presented: Rhodanthos, Godetia and Phaeostoma of the Clarkia Pursh. generic complex, outside their natural habitats (ex situ), on the collection site of the Novosibirsk State Agrarian University. As a result of the evaluation of the flowering phenomena of Clarkia sections, two flowering periods were identified. The species were distributed into summer-flowering plants C. purpurea from the Godetia section - with a vegetation duration of 102 ± 2 days and summer-autumn C. amoena and C. amoena subsp. Lindleyi from the Rhodanthos section with a vegetation duration of 123 ± 2 days and a species of C. unguiculata blooming throughout the period from the Phaeostoma section with a vegetation duration of 126 ± 2 days. Correlation analysis showed a high dependence of the growth and development periods of Clarkia species on the sum of biologically active temperatures > 10 °C (0.77 - 0.99). Cpurpurea from the Godetia section has the greatest adaptive potential to local climatic conditions, it requires the least amount of biologically active temperatures of the growing season (1903 °C) for growth and development than two other sections: Phaeostoma (2090 °C), Rhodanthos (2188 °C). Thus, all three sections of the Clarkia family Onagraceae Juss. they are characterized by prolonged flowering in the conditions of the forest-steppe of Western Siberia, are promising for urban gardening, differ in the possibility of sowing seeds in the open ground and are suitable for flower beds of continuous flowering.

Flowering time advances since the 1970s in a sagebrush steppe community: Implications for management and restoration.

Climate change is widely known to affect plant phenology, but little is known about how these impacts manifest in the widespread sagebrush ecosystem of the Western United States, which supports a number of wildlife species of concern. Shifts in plant phenology can trigger consequences for the plants themselves as well as the communities of consumers that depend upon them. We assembled historical observations of first-flowering dates for 51 species collected in the 1970s and 1980s in a montane sagebrush community in the Greater Yellowstone Ecosystem and compared these to contemporary phenological observations targeting the same species and locations (2016-2019). We also assembled regional climate data (average spring temperature, day of spring snowmelt, and growing degree days) and tested the relationship between first-flowering time and these variables for each species. We observed the largest change in phenology in early-spring flowers, which, as a group, bloomed on average 17 days earlier, and as much as 36 days earlier, in the contemporary data set. Mid-summer flowers bloomed on average 10 days earlier, nonnative species 15 days earlier, and berry-producing shrubs 5 days earlier, while late summer flowering plants did not shift. The greatest correlates of early-spring and mid-summer flowering were average spring temperature and day of snowmelt, which was 21 days earlier, on average, in 2016-2019 relative to the 1973-1978 observations. The shifts in flowering phenology that we observed could indicate developing asynchronies or novel synchronies of these plant resources and wildlife species of conservation concern, including Greater Sage-grouse, whose nesting success is tied to availability of spring forbs; grizzly bears, which rely heavily on berries for their fall diet; and pollinators. This underscores the importance of maintaining a diverse portfolio of native plants in terms of species composition, genetics, phenological responsiveness to climatic cues, and ecological importance to key wildlife and pollinator species. Redundancy within ecological niches may also be important considering that species roles in the community may shift as climate change affects them differently. These considerations are particularly relevant to restoration and habitat-enhancement projects in sagebrush communities across western North America.

WHAT DETERMINES THE FLOWERING OF ASTER L., HETEROTHECA CASS., MIYAMAYOMENA KITAM. AND SYMPHYOTRICHUM NEES GENERA PLANTS?

The assortment of ornamental perennial herbaceous plants in Lithuania is growing every year. Spring and summer flowering plants and ornamental plants of the Poaceae family are mainly grown in Lithuania. The first frosts in Lithuania usually occur in September-October, when some plants freeze. The aim of this study was to investigate the assortment of perennial herbaceous plants of the latest flowering family Compositae and what climatic factors influence their flowering time and duration. The research was carried out in Vytautas Magnus University Botanical Garden in 2019-2020.

For everything there was a season: phenological shifts in the Tetons ecosystem

Phenology — the timing of ecological events — is shifting as the climate warms. Grand Teton National Park biologists have identified this topic (“effect of earlier plant flowering on pollinators and wildlife”) as one of their priority research needs. To address this, we assembled phenological observations of first flowering dates for 48 species collected by Frank Craighead, Jr. in the 1970 and 80s. We hypothesized many species would be flowering earlier now. In 2016 we began standardized observations in the same locations targeting the same species plus 62 for a total of 110. We compare four years of contemporary to historic observations to demonstrate shifts in phenology, and use local weather data to identify the key climatic drivers. The largest effect is observed in early spring flowers, which are blooming ~17 days earlier. Mid-summer flowers bloom ~12 days earlier, and berries bloom ~7 days earlier. Not all species are emerging earlier, particularly late summer flowering plants. Also individual species within these functional groups differ in their responses. The greatest drivers of early spring and mid-summer flowering are average spring temperature (March, April, May) and the day of snow melt timing. Late summer flowers respond more to the accumulation of Growing Degree Days.
 
 Featured photo by Shawna Wolf, taken from the AMK Ranch photo collection.

Hibiscus Leaf Tissue Nutrient Sufficiency Ranges by Chronological Age

Perennial hibiscus (Hibiscus sp.) are popular summer-flowering plants that are grown in greenhouses or nurseries, where growers must optimize production inputs such as fertility to maximize plant growth and produce high-quality flowering crops. The objective of this study was to determine the optimum fertilizer concentrations, identify leaf tissue nutrient sufficiency ranges by chronological age, and to expand leaf tissue nutrient standards of Hibiscus hybrid L. (hibiscus) grown in soilless substrates during container production. Two cultivars of hibiscus (H. hybrid L. ‘Mocha Moon’ and ‘Starry Starry Night’) were grown under one of six constant liquid fertilizer concentrations [50, 75, 100, 200, 300, or 400 mg·L−1 nitrogen (N)] with a constant level of water-soluble micronutrient blend in a greenhouse. The fertilizer concentrations sufficient for optimal plant growth and development were determined by analyzing plant height, diameter, growth index (GI), primary shoot caliper (PSC), and total dry mass, and they were found to be 100–300 mg·L−1 N after an 8-week crop cycle. Recently, mature leaf tissue samples were collected and analyzed for elemental content of 12 nutrients at 2, 4, 6, and 8 weeks after transplant (WAT) from plants fertilized with 100–300 mg·L−1 N. An overall trend of increasing sufficient tissue concentration over time was observed for total N, phosphorus (P), calcium (Ca), sulfur (S), zinc (Zn), copper (Cu), and boron (B), whereas a decreasing trend was observed for potassium (K), iron (Fe), manganese (Mn), and aluminum (Al). For instance, at 2 WAT, total N ranged from 3.1% to 5.1% N and increased to a range of 4.2% to 4.7% N at 8 WAT. At 2 WAT, Fe and Mn ranged from 79.2 to 103.6 mg·L−1 Fe and 66.3–82.8 mg·L−1 Mn and decreased to ranges of 75.6–82.9 mg·L−1 Fe and 18.1–99.7 mg·L−1 Mn at 8 WAT, respectively. Optimal leaf tissue concentration sufficiency ranges determined in this scientifically-based study were narrower than previously reported survey values for the genera Hibiscus.

Taxonomic analysis of early spring and summer flowering plants of Talysh (Yardimli) territory within Azerbaijan

Taxonomic analysis of early spring and summer flowering plants of Talysh (Yardimli) territory within Azerbaijan

Сезонні ритми розвитку Hyssopus officinalis за культивування в умовах Житомирського Полісся

<p>The duration of phenological phases of 1-7-yeats-old <em>Hyssopus</em><em> officinalis</em> and its seasonal rhythms depending on the abiotic conditions of growth are established. It has been proved that hyssop belongs to late species by the terms of regrowth, the spring phase of which begins with the establishment of stable heat in April-May. The hyssop is attributed to the summer flowering plants, the flowering is the longest phase, and mass flowering is registered in July-August. Hyssop is a spring-summer-autumn-green plants, which begin the vegetation in spring, and in autumn they stay under the snow in green. Climatic conditions during the years of research were marked by temperature and precipitation fluctuations that affected the duration of the growing season and individual phenophases. First year seedlings of H. officinalis had the period of intensive growth and development from sowing to a period of rest was 159 days, whereas in Zhytomyr Polissya the sum of active temperatures was 2610 °С and sum of effective temperatures – 1180 °С. For 2-7-year-old hyssops the period from the spring regeneration to the death of the blooming plants and the formation of seeds lasted an average for 144 days (from 133 days in 2010 to 147 days in 2014). The range of temperatures required for the entire period was insignificant: active - from 2548.2 °C (2011) to 2696.3 °C (2012); effective - from 1152 °C (2009) to 1402.2 °C (2010). Compared with other phenological phases during the blooming period, plants require considerably more heat. The water scarcity did not affect significant on the duration of H. officinalis season rhythms. It is shown that to complete the development cycle of H. officinalis from the total amount of active temperatures was spent on average: for germination of seeds and spring regrowth – 5.9%, for stem formation phase – 13.5%, budding – 22.11%, blooming – 29.5%, fruiting – 16.5%, seeds maturation and pedicels dying – 12.6%; effective temperatures, respectively - 5.2%, 11.9%, 22%, 32.6%, 17.7%, 10.5%. The climatic conditions of Ukrainian Polissya allow to obtain hyssop plant raw material during one growing season, that indicates the adaptation of the species to the new conditions of growth. </p>

Heredity of flake- and stripe-variegated traits and their introduction into Japanese day-neutral winter-flowering sweet pea (Lathyrus odoratus L.) cultivars.

Sweet pea (Lathyrus odoratus L.) is a major cut flower in Japan, generally grown in greenhouses in winter to spring. The wild-type sweet pea is a long-day summer-flowering plant. The day-neutral winter-flowering ability, which allows cut-flower production in Japan, is a recessive phenotype that emerged by spontaneous mutation. Although Japanese winter-flowering cultivars and additionally spring-flowering cultivars, which have semi-long-day flowering ability generated by crossing the winter- and summer-flowering cultivars, have superior phenotypes for cut flowers, they have limited variation in color and fragrance. In particular, variegated phenotypes do not appear in modern winter- and spring-flowering cultivars, only in summer-flowering cultivars. We try to expand the phenotypic diversity of Japanese cut flower cultivars. In the processes, we introduced the variegated phenotypes by crossing with summer-flowering cultivars, and succeeded in breeding some excellent cultivars. During breeding, we analyzed the segregation ratios and revealed the heredity of the phenotypes. Here we review the heredity of these variegated phenotypes and winter-flowering phenotypes and their related genes. We also describe how we introduced the trait into winter-flowering cultivars, tracing their pedigrees to show both phenotypes and genotypes of the progeny at each generation. This knowledge is useful for the efficient breeding of new variegated cultivars.

Japanese white-eyes (Aves: Zosteropidae) as potential pollinators of summer-flowering Taxillus kaempferi (Loranthaceae)

ABSTRACTThe pollination of summer-flowering plants by birds has rarely been reported in temperate Asia and Europe. However, we recorded the Japanese white-eye Zosterops japonicus (Passeriformes: Zosteropidae) visiting the flowers of the hemiparasitic plant Taxillus kaempferi (Loranthaceae) during mid-summer (July to August) in a temperate forest in central Japan. Field observations showed that Z. japonicus was an almost exclusive flower visitor of T. kaempferi. Specifically, Z. japonicus inserted their bills frequently into the flower tubes of T. kaempferi. The corollas of T. kaempferi were shorter than Z. japonicus bills, suggesting that Z. japonicus is able to obtain floral nectar from T. kaempferi. Close-up pictures of Z. japonicus visiting flowers showed that the upper bill and facial feathers of Z. japonicus came into contact with the reproductive organs of T. kaempferi, leading to the attachment of pollen to these body parts. Thus, Z. japonicus might act as an important pollinator of the summer-flowering plant T. kaempferi.​

Systematics and biology of the African genus <i>Ferraria</i> (Iridaceae: Irideae)

Following field and herbarium investigation of the subequatorial African and mainly western southern African Ferraria Burm. ex Mill. (Iridaceae: Iridoideae), a genus of cormous geophytes, we recognize 18 species, eight more than were included in the 1979 account of the genus by M.P. de Vos. One of these, F. ovata, based on Moraea ovata Thunb. (1800), was only discovered to be a species of Ferraria in 2001, and three more are the result of our different view of De Vos’s taxonomy. In tropical Africa, F. glutinosa is recircumscribed to include only mid- to late summer-flowering plants, usually with a single basal leaf and with purple to brown flowers often marked with yellow. A second summer-flowering species, F. candelabrum, includes taller plants with several basal leaves. Spring and early summer-flowering plants lacking foliage leaves and with yellow flowers from central Africa are referred to F. spithamea or F. welwitschii respectively.

Consistent flowering response to global warming by European plants introduced into North America

Summary1. The reliability of species distribution models (SDM) to predict the probable response of alien plants to climate change rests on the assumption that plant performance in relation to temperature in the introduced range will be similar to that observed in the native range. Yet, alien plants may exhibit enhanced performance or different environment‐distribution relationships following their introduction into a new area. Empirical data are therefore essential to test whether the responsiveness of species to climate is equivalent in the native and introduced ranges.2. This study tests the assumption that phenological responses of plants to temperature are similar in both their native and introduced range. First flowering date (FFD) is widely used to assess the responsiveness of plants to recent warming arising from global change. For 19 species native to Europe, FFD observed in both the UK and USA between 1970 and 2000 was examined in relation to interannual variation in local temperatures. General trends, variability and responsiveness of FFD to warming were examined for consistency in the contrasting climate of Oxfordshire and Washington DC.3. Mean FFD in Oxfordshire was a powerful predictor of the same variable in Washington DC, although summer flowering plants in Oxfordshire tended to flower earlier in the season in Washington DC. FFD varied considerably over 30 years, but across all species, the range in FFD revealed a similar trend in both regions with larger ranges observed for earlier flowering species.4. Comparable trends were found between Oxfordshire and Washington DC in the degree to which flowering advanced or regressed per unit temperature increase. In response to warming, the majority of species flowered earlier in both countries and the degree to which FFD responded to increasing temperature was greatest for species flowering earlier in the year.5. These equivalent phenological responses to temperature across continents imply prediction of the performance of alien plants under climate change may be derived from a species’ behaviour in its native range. While these findings support the use of SDM, they also indicate that these models could be significantly improved through the integration of phenological relationships parameterized from data in the native range.

Is the onset of the English summer advancing?

British summers are known to have become warmer and drier in recent decades, but has there also been a change in the timing of this season’s beginning, as has occurred for spring? This paper addresses this question by examining records of the first blooming date of early summer flowering plants (phenology) and the timing of first occurrences of warm ‘summer’ temperatures, both events that we associate with the onset of summer. This has revealed that the onset of summer in England has been advancing since the mid 1950s. The occurrence of ‘summer’ temperatures has advanced more than early summer flowering, by eleven and three days respectively in the 1990s compared to the period 1954–1963. This may have encouraged drought or heat wave conditions by prolonging the period of warm temperatures and lower rainfall in which these events occur.

Botanical and zoological remains from an early medieval grave at Tsitsamuri, Georgia

A multidisciplinary analysis of pollen, seeds, mites and molluscs from organic remains in the Tsitsamuri burial (4th–6th century a.d.) provides strong evidence of the season of internment. The presence of Trifolium campestre flowers, abundant Achillea-type pollen, ripe seeds from various early summer flowering plants, remains of Acari mites and immature Helicella derbentina mollusc shells indicate that the burial took place in early summer. Textile fragments were also analysed and indicate that the body was wrapped in a shroud made of flax. The deceased was interred on a bed made of plants gathered from the local environment. The whole complex of botanical and zoological material indicates a cultural landscape in which agriculture, viticulture, horticulture and pasturing were carried out. The climate of that period was probably slightly wetter and warmer than today.

Seasonal deposition of Holocene banded sediments in the Severn Estuary Levels (southwest Britain): palynological and sedimentological evidence

Banded sediments outcrop widely in the intertidal zone of the Severn Estuary and have been suggested, on the basis of textural analysis, to have formed in response to seasonal variations in sea temperature and windiness (Holocene, 14 (2004) 536). Here palynological and sedimentological analyses of banded sediments of mid-Holocene date from Gold Cliff, on the Welsh side of the Severn Estuary, are combined to test and further develop the hypothesis of seasonal deposition. Pollen percentage and concentration data are presented from a short sequence of bands to establish whether textural variations in the bands coincide with variations in pollen content reflecting seasonal flowering patterns. It is shown that fine-grained band parts contain higher total pollen concentrations, and a higher proportion of pollen from late spring- to summer-flowering plants, than coarse-grained band parts. Pollen in the coarser deposits appears primarily to reflect deposition from the buffering ‘reservoir’ of suspended pollen in the estuarine water-body and from rivers, when there is little pollen in the air in winter, while the finer sediments contain pollen deposited from the atmosphere during the flowering season, superimposed on these ‘background’ sources. The potential of such deposits for refining chronologies and identifying seasonality of coastal processes is noted, and the results of charcoal particle analysis of the bands presented as an example of how they have the potential to shed light on seasonal and annual patterns of human activity.

Some Records of the Seasonal Flora of Arable Land Under Cultivation

For several years the writers have kept accurate records of the numerical and seasonal occurrence of the weeds of arable land under ordinary culture. The flora of any arable field is exceedingly scanty both as regards number and species, rarely more than 30-35 species commonly occurring on a farm lying over a single geological outcrop, that is, with only one fairly uniform type of soil. Special clay, sand, loam or chalk plant-associations develop according to the character of the soil, and by reason of the agricultural operations carried out through the year these associations are composed almost entirely of annuals, with seedlings and young plants of those perennials which have wind-borne fruits capable of rapid germination; such species form the first vegetation on waste land when abandoned by the farmer. The frequency of occurrence of arable land weeds and the flora types met with on different geological horizons have been worked out by Dr Winifred Brenchley1 who, however, only observed the relative frequency of summer flowering plants in growing crops without reference to their actual number and seasonal distribution. Plant counts of old pastures have been carefully made by S. F. Armstrong2 and others, but again only for special areas and in the summer. Seasonal records of arable land plants have also been recorded for certain western pastures and arable by R. G. Stapledon3 who counted the plants in several small areas (one sq. foot) at intervals throughout the year, the squares being selected haphazard from different parts of the same field and the counts added together. None of these methods, however, gives an idea of the number of plants surviving ordinary agricultural operations on arable land throughout the season, and the authors therefore arranged an experiment to determine the succession of plants on one plot of land over an entire year. Their method was as follows: A square wooden frame with an inside area of one yard was thrown down in a field at a fixed distance (two chains) from the headlands. The exact site was noted by measuring coordinates to pegs fixed in the hedgerows at right angles to the sides of the frame. Pegs were thrust down nearly flush with the ground at each corner and left there when the frame was lifted up so that it could be easily slipped back on the same place at the subsequent visits. The