Flower Abundance Research Articles

Изучение сортов каллистефуса китайского (Callistephus chinensis L.) в условиях криолитозоны

Abstract. Purpose: to study promising varieties of Callistephus chinensis L.in the conditions of the cryolithozone. The article presents the results of the study of Callistephus chinensis L. of 12 different varieties in the sharply continental climate of Yakutia. Callistephus chinensis L. is an annual herbaceous, bright and beautifully flowering plant. But at the same time it has resistance, this is especially important in the conditions of the cryolithozone, where the choice of beautifully flowering plants is limited. Subject of research: seasonal development of Callistephus chinensis L. varieties in cryolithozone conditions. Callistephus is well suited for landscaping urban landscapes, due to their decorative nature, a variety of colors, resistance to many environmental factors and abundant flowering. The introduction of Callistephus chinensis L. species, as well as the breeding of cold-resistant varieties is one of the urgent problems of gardening in Central Yakutia. In the laboratory and in the greenhouses of the Arctic State Agrotechnological University, variety tests of Callistephus chinensis L. were conducted to identify the most adaptive varieties. Methods. Sowing was carried out with full-weight seeds with determination of germination energy and germination. The analyses were carried out in the State Administration “State Ministries Inspection” of the Republic of Sakha (Yakutia). Different varieties of Callistephus chinensis L. were grown in a seedling way. Results. Seedling cultivation led to an elongation of the growing season and the duration of flowering, which ultimately made it possible to achieve a longer decorative effect; the ability of some varieties of Callistephus chinensis L. to withstand drought, resistance to adverse conditions, such varieties as Bal’fe khudozhestvennaya, Yabluneva, Mtsenskiy rubin, Berezka, Rubinovye zvezdy were revealed to be the most adaptive to gardening in Central Yakutia. Scientific novelty. In order to identify the most adaptive varieties in the conditions of the cryolithozone, variety tests of Callistephus chinensis L. were carried out.

FaMYB6-like negatively regulates FaMYB10-induced anthocyanin accumulation during strawberry fruit ripening

Anthocyanins are one of the essential compounds affecting the quality of strawberry fruit. Several R2R3-MYB transcription factors have been well characterized as the anthocyanin activators in strawberry. However, we still lack valuable information on how R2R3-MYB repressors regulate strawberry anthocyanin accumulation. Here, we cloned a novel R2R3-MYB gene, FaMYB6-like, and characterized its repressive role during anthocyanin accumulation. FaMYB6-like encodes a nuclear localization protein, which was clustered into the FaMYB1-like type repressor clade in phylogenetic analysis. FaMYB6-like showed high expressions in anthocyanin-accumulating fruit and low transcript abundance in flowers, vegetative tissues, and early development stages of fruit. Transient overexpression of FaMYB6L-like repressed the expression of anthocyanin biosynthetic and transport genes, and reduced anthocyanin content in postharvest strawberry fruit. Transgenic tobacco lines overexpressing FaMYB6-like displayed a reduction in petal pigmentation. Overexpression of FaMYB6L-like in white-fleshed strawberry inhibited anthocyanin accumulation induced by FaMYB10. Protein interaction and promoter activation assays revealed that FaMYB6-like repressed the activation of target gene promoters by FaMYB10-FabHLH3 activation complex via its interaction with FabHLH3. Additionally, FaMYB6-like promoter activity can be activated by FaMYB10-FabHLH3 complex. Taken together, our study revealed that FaMYB6-like acted as a transcriptional repressor involved in an ‘activator-and-repressor’ feedback regulation mechanism for maintaining the balance of anthocyanin concentrations.

Tropical agroforestry supports insect pollinators and improves bean yield

Abstract Pollination services contribute to crop productivity worldwide, but insect pollinators are declining in most agricultural landscapes, mainly due to agricultural expansion and an increase in intensive agricultural practices. To reduce the negative effects of agricultural expansion and intensification, farmers can adopt ecological interventions, such as diversifying agricultural systems through agroforestry. However, there have been variable results on the effectiveness of agroforestry in enhancing pollinators and pollination services. Furthermore, most of the information has been generated in temperate regions, while the impact of agroforestry in tropical East Africa is largely unknown. Using common beans (Phaseolus vulgaris L.) as the focal crop, this study tested whether a tropical agroforestry system called Chagga home gardens supports pollinator communities and improves pollination and crop yield. We examined 16 agroforestry plots paired with 16 non‐agroforestry plots located along a gradient of woody (trees and shrubs) cover within a 1‐km radius to document the abundance, species richness and visitation rates of pollinating insects on bean flowers and how they contributed to bean yield. The beans planted in the agroforestry plots had almost twice the abundance of insect pollinators, three times the richness of the species and almost twice the visitation rates than those planted in non‐agroforestry plots. We also found a significant positive effect of woody cover in the surrounding landscape on insect pollinator abundances, but not on species richness and visitation rates. Additionally, the abundance and richness of insect pollinators increased significantly with flower abundance, while the overall plant richness in a plot significantly increased insect pollinator abundance and their visitation rate. The difference in bean yield between unbagged flowers (in which insect pollinators were allowed to access bean flowers) and bagged flowers and the total yield were higher in agroforestry than in non‐agroforestry plots. Synthesis and applications. This study showed that, compared to monoculture, agroforestry generally promotes pollination services in a tropical context. Furthermore, we found that agroforestry is likely to be particularly helpful for pollinators when it increases flower abundance and plant richness and if it is coordinated so that woody cover also increases at the landscape scale.

An Efficient Method for the Propagation of Bougainvillea glabra ‘New River’ (Nyctaginaceae) from In Vitro Stem Segments

Bougainvillea, an evergreen climbing shrub of the Nyctaginaceae family, holds significant ornamental, economic, and medicinal value. Bougainvillea glabra ‘New River’ is widely used in landscapes due to its strong adaptability to the environment, abundance of flowers, and frequent flowering. Traditionally, Bougainvillea glabra ‘New River’ cultivation has relied on methods such as cuttings or grafting, with limited research on in vitro tissue culture propagation. This study aimed to optimize the tissue culture system, exploring a combination of plant growth regulators (PGRs) for Bougainvillea regeneration from in vitro stem segments. The Murashige and Skoog (MS) medium supplemented with indole-3-butyric acid (IBA), 6-benzylaminopurine (6-BA), and 1-naphthlcetic acid (NAA) was employed. The optimal sterilization of Bougainvillea stem segments involved a 30 s treatment with 75% alcohol and 10 min with 1% NaClO. The synergistic effect of 0.1 mg·L−1 of NAA and 2.5 mg·L−1 of 6-BA maximized the shoot sprouting frequency, while 2.5 mg·L−1 of 6-BA and 0.1 mg·L−1 of NAA produced the maximum shoots. Furthermore, 1.5 mg·L−1 of IBA and 0.1 mg·L−1 of NAA induced the highest rooting levels. This work demonstrates the successful adaptation of a greenhouse environment to efficiently regenerate plants in vitro from stem segments. This approach allows for the mass production of Bougainvillea glabra ‘New River’.

Standardising bee sampling: A systematic review of pan trapping and associated floral surveys.

The use of coloured pan traps (bee bowls, Moericke traps) for sampling bees (and other pollinators) has continuously increased over the last two decades. Although a number of methodological studies and conceptual frameworks offer guidance on standardised sampling, pan trap setups vary widely in characteristics even when optimised for capturing bees. Moreover, some uncertainty persists as to how local flower abundance and diversity influence sampling. We systematically reviewed peer-reviewed studies that used pan traps for bee collection and that were listed in the Web of Science core collection. To gauge methodological variation, we identified a set of relevant methodological criteria and assessed the studies accordingly. For obtaining evidence that pan trap samples and floral environment around traps are correlated, we screened the relevant studies for such correlations. While some aspects of pan trapping (e.g., trap coloration and elevation) were similar in the majority of studies, other aspects varied considerably (e.g., trap volume/diameter and sampling duration). Few studies used floral abundance and/or diversity as an explanatory variable in their analyses of bee samples. Among these studies, we found a considerable variation in key aspects of floral survey methods, such as time and space between vegetation surveys and pan trap sampling, abundance measures (quantitative, semi-quantitative and presence-absence), and processing of raw data prior to analysis. Often studies did not find any correlation between the floral environment and bee samples. Reported correlations varied markedly across studies, even within groups of studies applying a similar method or analysing a similar group of bees. Our synthesis helps to identify key issues of further standardisation of pan trap methodology and of associated floral surveys. In addition to the few aspects that have been standardised over the past decades, we suggest methodological direction for future research using pan traps as a better standardised method for the collection of wild bees. We encourage further studies to illuminate if and how varying floral resources around traps bias bee samples from pan traps. More generally, our synthesis shows that trapping methodologies should be reviewed regularly when their use increases to ensure standardisation.

Using photographs and deep neural networks to understand flowering phenology and diversity in mountain meadows

AbstractMountain meadows are an essential part of the alpine–subalpine ecosystem; they provide ecosystem services like pollination and are home to diverse plant communities. Changes in climate affect meadow ecology on multiple levels, for example, by altering growing season dynamics. Tracking the effects of climate change on meadow diversity through the impacts on individual species and overall growing season dynamics is critical to conservation efforts. Here, we explore how to combine crowd‐sourced camera images with machine learning to quantify flowering species richness across a range of elevations in alpine meadows located in Mt. Rainier National Park, Washington, USA. We employed three machine‐learning techniques (Mask R‐CNN, RetinaNet and YOLOv5) to detect wildflower species in images taken during two flowering seasons. We demonstrate that deep learning techniques can detect multiple species, providing information on flowering richness in photographed meadows. The results indicate higher richness just above the tree line for most of the species, which is comparable with patterns found using field studies. We found that the two‐stage detector Mask R‐CNN was more accurate than single‐stage detectors like RetinaNet and YOLO, with the Mask R‐CNN network performing best overall with mean average precision (mAP) of 0.67 followed by RetinaNet (0.5) and YOLO (0.4). We found that across the methods using anchor box variations in multiples of 16 led to enhanced accuracy. We also show that detection is possible even when pictures are interspersed with complex backgrounds and are not in focus. We found differential detection rates depending on species abundance, with additional challenges related to similarity in flower characteristics, labeling errors and occlusion issues. Despite these potential biases and limitations in capturing flowering abundance and location‐specific quantification, accuracy was notable considering the complexity of flower types and picture angles in this dataset. We, therefore, expect that this approach can be used to address many ecological questions that benefit from automated flower detection, including studies of flowering phenology and floral resources, and that this approach can, therefore, complement a wide range of ecological approaches (e.g., field observations, experiments, community science, etc.). In all, our study suggests that ecological metrics like floral richness can be efficiently monitored by combining machine learning with easily accessible publicly curated datasets (e.g., Flickr, iNaturalist).

First report of Diaporthe eres causing leaf spot on Rhododendron latoucheae Franch. in China.

Rhododendron latoucheae Franch. is an evergreen shrub with charming fragrance and large and abundant flowers that make it highly attractive as an ornamental species. The species is distribution in southwest China covers several different habitats and environments (Zhang, et al. 2022). From May to July in 2023, symptoms of leaf spot were observed on R. latoucheae over a wide portion of the Baili Azalea Forest Area (27°10' to 27°20'N, 105°04' to 106°04'E), Guizhou Province, China. About 500 plants were surveyed, and the incidence of leaf spot on R. latoucheae leaves was 12%, significantly reducing their ornamental and economic value. The affected leaves had irregular, grey white lesions with a clear blackish brown boundary and faint black conidiomata in a brown center. To isolate the pathogen, 15 symptomatic leaves were collected from 10 plants. A few black dots were picked from the lesions with a sterilized needle, plated on water agar, and incubated at 25°C for 24 h to observe spore germination (Choi et al. 1999). Then the germinated spores were transferred onto PDA for further purification and morphological observation. Three single-spore isolates (GULJ1-L7, GULJ1-L8, and GULJ1-L9) identical in morphology were obtained. The isolate GULJ 1-L7 was used for further study. Colonies on PDA irregular grew white felty aerial mycelium, becoming white felted aerial mycelium in the centre and grey-brown mycelium at the marginal area on the upper surface, while the lower surface presents alternating white, tan and taupe. Colony with conidiomata irregularly distributed over agar surface. In the representative isolate, darkly pigmented pycnidia (flask-shaped) were produced over the colony surface on PDA after about 30 days, and oozed milky or yellowish mucilaginous drops. The fungus produced two types of conidia, α and β. Regular α conidia were 5.15-10.29 × 1.54-3.33 μm (n = 50), hyaline, elongated, biguttulate and non-septate. Beta conidia were 20.34-31.91 × 1.01-1.90 μm (n = 50), aseptate, hyaline, smooth, spindle shaped, slightly curved to bent. The morphological features were consistent with the description of Diaporthe eres (Pereira, et al. 2022). The pathogen was confirmed to be D. eres by amplification and sequencing of the internal transcribed spacer region (ITS), the partial β-tubulin (TUB), the partial translation elongation factor 1-alpha (TEF) genes and the calmodulin (CAL) using primers ITS1/ITS4, Bt-2a/Bt-2b, EF1-728F/EF1-986R, and CAL-228F/CAL-737R, respectively (Tao et al. 2020). Sequences from PCR amplification were deposited in GenBank with accession numbers OR740563 (ITS), OR754301 (TUB), OR754298 (TEF), and OR754295 (CAL) respectively. BLAST searches of the sequences revealed 99.07% (533/538 nt), 100% (490/490 nt), 99.69% (317/318 nt) and 98.95% (376/380 nt) homology with those of D. eres AR5193T from GenBank (KJ210529.1, KJ420799.1, KJ210550.1 and KJ434999.1), respectively. Phylogenetic analysis (MEGA 7.0) using the maximum-likelihood method placed the isolate GULJ1-L7 in a well-supported cluster with D. eres CBS 138694T. The pathogen was thus identified as D. eres based on the morphological characterization and molecular analyses (Feng, et al. 2013; Tao, et al. 2020). The pathogenicity of GULJ1-L7 was tested through a pot assay. Due to the difficulty of artificial planting wild R. latoucheae, we conducted a pot essay to detect the pathogenicity of GULJ1-L7 using a closely related Rhododendron delavayi Franch. Ten healthy R. delavayi plants were scratched with a sterilized needle (0.45 mm in diameter) on three leaves per plant. Plants were inoculated by spraying α and β spore mixture suspension (106 spores ml-1) of GULJ1-L7 onto leaves until runoff, and the control leaves were sprayed with sterile water. The plants were maintained at 25°C and 75% relative humidity in a growth chamber. The pathogenicity test was repeated three times. After 14 days, the treated leaves developed brown lesions similar to those in the field, whereas the control had no symptoms. The same fungus was reisolated from the infected leaves and identified based on a morphological characterization and molecular analyses. These results fulfilled Koch's postulates. To our knowledge, this is the first report of leaf spot on R. latoucheae caused by D. eres in China. The fungal pathogen identification will provide valuable information for prevention and management of leaf spot disease associated with R. latoucheae.

Beware of trees: Pine afforestation of a naturally treeless habitat reduces flower and pollinator diversity

Planting three billion trees to capture carbon and seeking measures to reverse pollinator decline are two key pledges of the EU Biodiversity Strategy for 2030. Although planting trees could be adequate to restore biodiversity in degraded landscapes and mitigate anthropogenic carbon emissions, it can also negatively impact biodiversity of naturally treeless habitats. To explore whether these two pledges might conflict, we focused on the European dry heathland, a treeless habitat frequent in the southwestern Iberian Peninsula, where it is locally known as herriza. The herriza stands out by its high plant biodiversity and profuse flowering that supports a wide range of insect pollinators. Yet, the herriza has been heavily afforested with pine trees until the onset of the 21st century. This past activity provides a unique natural experiment to assess the effect of afforestation on flower abundance and associated pollinator diversity. We conducted a two-year field study of the diversity and abundance of flowers and pollinators in five selected sites, each consisting of two adjacent plots of open and afforested herriza. Afforested herriza plots had consistently lower diversity and abundance of flowers and insect pollinators than open herriza plots. Our results highlight the negative impact of afforestation of a treeless habitat on its flowering pattern and associated insect pollinator guilds. We thus suggest seeking alternatives to afforesting naturally treeless habitats in order to avoid conflicts between carbon sequestration and pollinator conservation.

Effective population size mediates the impact of pollination services on pollen limitation.

Inadequate pollen receipt limits flowering plant reproduction worldwide. Ecological causes of pollen limitation (PL), like pollinator scarcity and low plant abundance, have been a primary research focus. The genetic diversity of plant populations could impact both quantity and quality components of PL in concert with ecological factors, yet empirical examples are lacking. We evaluated joint effects of ecological factors (flower abundance, pollinator visitation) and genetic effective population size (NE) on PL across 13 populations of the common herb Argentina anserina. We used a histological approach with 5504 styles from 1137 flowers to separate quantity and quality components of PL, and link these to reproductive output. NE and pollinator visitation interacted to shape PL, but NE had stronger direct effects. Effectively smaller populations experienced stronger quantity PL, and controlled crosses in a pollinator-free environment revealed that stigmatic pollen quantity was an intrinsic population-level attribute that increased with NE. Pollinator visitation enhanced pollen quality, but only in effectively larger populations. Quantity and quality PL negatively impacted fruit and seed set, respectively. Results highlight that PL is dictated by plant population genetic diversity in addition to commonly evaluated ecological factors. Efforts to support pollinators will more strongly enhance plant reproduction in genetically diverse populations.

Winter dry season reproductive phenology in Bahamian dry forest and implications for conservation

AbstractThe reproductive phenology of plants has profound influence on ecosystem dynamics including plant–animal interactions. Broad phenological patterns, especially the timing of reproduction, may result from long‐term climate trends and co‐evolution between plants and their pollinators, dispersers, and predators. Yet, interannual climate variation and local abiotic conditions may also affect the timing and magnitude of plant reproduction. Understanding the patterns of and controls on plant reproduction are crucial for conservation efforts under a changing global climate and rapidly expanding human development. However, phenology studies from the Neotropics are sparse. Here, we examine the relative timing and magnitude of fleshy‐fruited plant reproduction during the winter dry season in subtropical dry forest on Eleuthera, The Bahamas over a nine‐year period. At least 47 species were observed with some dry season reproductive activity, but only 17% showed evidence of a fruiting peak or continuous reproduction. Overall fruit abundance generally declined through the dry season, but flower production increased between mid and late dry season. Variation in fruit and flower abundance among years was related to temperature and rainfall, but local site conditions—particularly successional stage and groundwater availability—explained more variability in reproductive activity than climate variation. Groundwater availability had a particularly strong positive influence on flower and fruit abundance at the end of the dry season, a critical time for migrant frugivores preparing to return to their breeding grounds. This emphasizes the importance of protecting sites with accessible groundwater to conserve biodiversity in the archipelago and elsewhere.

Особенности фенологии некоторых представителей рода Rosa L. в условиях Европейского Севера

The article presents the results of observations of the onset of phenological phases in representatives of the genus Rosa L. in the conditions of the European North. Roses are widely used in landscaping of settlements as ornamental, medicinal and fruit plants. The research was carried out in the Dendrological Garden named after I.M. Stratonovich (Arkhangelsk). Objects of research are plants of the genus Rosa L.: R. pendulina L., R. majalis Herrm., R. laxa Retz., R. spinosissima L., R. rugosa Thunb., R. × hybrida, R. glauca Pourett. The European group of geographical origin accounts for 45% of the studied species, the Asian and Far-Eastern – 27% each. The introduced species are the first to bloom in the European North (late 2nd decade of June): R. × hybrida, R. rugosa, R. rugosa ‘Plena’ and R. spinosissima ‘Plena’. R. majalis, R. spinosissima, R. pendulina are distinguished by abundant flowering (flowering score – 5). Fruit ripening begins at the end of August in R. rugosa ‘Plena’ and continues until the 3rd decade of September in R. glauca. The fruits hang on the shoots until mid-winter. The most abundant fruiting (4 points) in the conditions of Arkhangelsk is observed in R. majalis, R. spinosissima and R. pendulina; the minimum fruiting score (2 points) is assigned to R. glauca and R. rugosa ‘Plena’.

Leaf Spot Caused by Colletotrichum siamense, C. fructicola, and C. aeschynomenes on Ixora chinensis in Guangxi, China.

Ixora chinensis Lam., an important ornamental flower, has become more and more popular in the southwest and southeast regions of China for its bright and abundant flowers (Li et al. 2019). In March 2022, 100% I. chinensis plants showed typical anthracnose symptoms on leaf in Nanning, Guangxi, China (108°22' N, 22°48' E). The central areas of lesions were grayish white with small black particles arranged in a wheel pattern, and the edges of lesions were light red to brown. Three diseased leaf samples were collected from three gardens, respectively. 5×5 mm tissues were cut from infected margins, surface-disinfected in 75% ethanol for 10 s, 2% NaClO for 2 min, rinsed three times in sterilized distilled water, and incubated on PDA at 25°C under 12/12 h light/darkness. Eighty-three morphologically similar colonies were observed on PDA after 5 days, and eight isolates G1-3, G2-1, G3-3, W-1, W-2, LCH2-1, LCH3-3, and LCH4-1 were selected for further study. Genomic DNA of these isolates were extracted from 7-day-old mycelia. Primer pairs ITS1/ITS4, GDF1/GDR1, T1/βt2b, CHS Ⅰ-79F/CHS Ⅰ-354R, CL1/CL2, ACT-512F/ACT-783R, and MAT1-2-1/apn2 were used to amplify ITS loci and GAPDH, CHS-Ⅰ, CAL, ACT, ApMAT genes, respectively (Yang et al. 2009; Silva et al. 2012; Liu et al. 2015). Sequences have been deposited in GenBank (ITS: OQ771884 to OQ771891, GAPDH: OQ759576 to OQ759583, TUB2: OQ759584 to OQ759591, CHS-1: OQ759568 to OQ759575, CAL: OQ759560 to OQ759567, ACT: OQ759552 to OQ759559, ApMat: OQ759544 to OQ759551). Phylogenetic analysis was performed with raxmlGUI v.2.0.0. based on combined sequences of ITS, GAPDH, TUB2, CHS-1, CAL, ACT, and ApMAT using maximum parsimony analysis. The results revealed that isolates G2-1 and W-2 were clustered with Collectrichum fructicola, G3-3, W-1, G1-3, LCH2-1, and LCH3-3 were clustered with C. siamense, and LCH4-1 was clustered with C. aeschynomenes. Three representative isolates W-2, G3-3, and LCH4-1 were selected for morphology and pathogenicity observation. On PDA, the colonies of three isolates presented white to grey cottony mycelia，from the margin to the center, W-2 was white, grey, and light gray, G3-3 showed light gray, white, and grey, LCH4-1 was white and light gray, respectively. Conidia were all hyaline, one-celled, cylindrical, and straight. The conidial sizes of W-2, G3-3, and LCH4-1 were 11.03 to 17.53 × 4.93 to 8.42 μm (n=100), 10.63 to 19.06 × 3.73 to 6.92 μm (n=100), and 11.61 to 20.39 × 3.65 to 6.67 μm (n=100), respectively. Pathogenicity tests of three isolates were conducted on leaves of 1-year-old I. chinensis plants with and without wounds, three plants for each treatment, and five leaves inoculated for each plant. Conidial suspensions (10 µL, 106 conidia/mL in 0.1% sterile Tween 20) were inoculated on each site. Control group was treated with 0.1% sterile Tween 20. All inoculated sites were covered with wet cotton, and all plants were bagged and placed in the greenhouse to maintain humidity at 25℃. After 10 days, all wounded and inoculated leaves showed leaf spot, whereas unwounded and control leaves remained asymptomatic. Koch's postulates were fulfilled by re-isolating the causal agents from diseased leaves. C. siamense and C. aeschynomenes could cause anthracnose of I. chinensis in China (Liu et al. 2016, Li et al. 2021). However, to our knowledge, this is the first report of C. fructicola infecting I. chinensis in China. This study may provide reference for further epidemiological study and prevention of anthracnose on I. chinensis.

MODELING OF APPLE CHEMICAL FRUIT THINNING

Crop load management in intensive apple orchards must be done precisely to produce a high yield with marketable fruit size. It also ensures the formation of flower buds on the tree for the next season and prevents alternative bearing. In addition to pruning, flower and fruit thinning is another management method that has a major impact on crop yield. Compared to other methods, chemical thinning is the cheapest, can be done quickly and allows fruit thinning at the right time, which guarantees better fruit quality. The decision on the type of chemical agent, concentration and timing of application is very complex and depends on the apple variety, flowering intensity and fruit growth phase, weather conditions during treatment and a few days after. Flower thinning is applied to very high-yielding varieties where fruit thinning is very difficult and tends to bear alternately. Ammonium thiosulphate or ethephon can be used for this purpose only in years with abundant flowering and in conditions where there is no risk of spring frosts. Regardless of whether flower thinning has been carried out or not, the fruits are chemically thinned in the period shortly after flowering. The usual chemical treatment(s) is (are) applied at the early stage of fruit development, when the diameter of the central fruits in a cluster on 2-year-old wood is 5 to 16 mm (in exceptional cases up to 20 mm). At this time, naphthalene acetamide (NAD), naphthalene acetic acid (NAA), 6-benzyladenine (6- BA), and metamitron are used to induce abscission of young fruit. These chemicals are used alone or in various combinations to improve the effect. If the thinning efficacy of the single application is weak, sequential applications of chemical thinners with different modes of action must be made 1-3 weeks after the previous application to reduce fruit set to a commercially acceptable level. To avoid under- or over-thinning of fruit of a particular variety, models that predict the effectiveness of chemicals based on short-term light and temperature forecasts are used to determine the optimal time to apply thinners. Immediately after the first application of thinning agents, the “fruit growth rate model” can be used for early assessment of apple tree response to thinning and the need for a new application.

Новый сорт клевера ползучего Ритм

The article presents a description of a new variety of creeping clover 'Ritm'. The variety is recommended for lawn and pasture use. A creeping bush. The foliage is 80%. The yield of green mass is 34.7 t/ha. The yield of dry matter is 8 t/ha. The crude protein content is 24%. The seed yield is 1.6 centner/ha. A distinctive feature of the variety is its abundant flowering (up to 860 pcs/m2 heads) and early maturity. The period from the beginning of spring vegetation to full ripeness of seeds is 110–115 days, from the first mowing to full ripeness of seeds from — 50 to 65 days. The variety has a high winter hardiness. When evaluated in the field of infectious backgrounds, the 'Ritm' variety showed complex resistance to cancer and Fusarium.

About floristic records of the Mangystau flora

This article presents the geographical novelties of the Mangystau flora discovered during the botanical expedition in 2023. One of the oasis territories of the Mangistau desert is the mountainous and foothill strips of the mountainous Karatau. For the first time, three species of woody plants, Prunus spinosa L., Rosa iliensis Chrshan, Armeniaca vulgaris L. from the family Rosaceae Juss, were found in the gorges of Kogez, Akmysh, Samal of the Mountain Karatau in the valleys of streams and along the slopes of the mountains. Thickets of bushes Prunus spinosa L. and endemic species of South Kazakhstan Rosa iliensis Chrshan occupy an area from 100 to 200 m2, and there are several single specimens of a rare and endemic species with a decreasing range of Armeniaca vulgaris L several specimens. All species are in good condition, plants have a high vitality, and no signs of damage were noted. Prunus spinosa and Rosa iliensis also showed abundant flowering and fruiting.

Diversity and biological traits of bees visiting flowers of Cucurbita maxima var. zapallito differ between biodiversity-based and conventional management practices.

Low diversity of pollinators and the modified composition of functional groups of bees have been proposed as the causes of pollination deficiency in cultivated Cucurbitaceae species. Functional groups of bees are determined by traits, such as body size, nesting site, and social behavior. The presence of bees with specific traits can be differentially affected by agricultural management practices. This work aimed to assess how management types (agroecological and conventional) in Cucurbita maxima var. zapallito crops affect the abundance of bees with different biological traits. The study was conducted on four farms located in horticultural areas of central-eastern Santa Fe province, Argentina. A total of 108 10-min censuses were conducted to record bee species abundance in flowers. The species were assigned to categories for each of the three biological traits. A total of 552 individuals, belonging to 16 bee species, were recorded. Honey bees were more abundant under conventional management, whereas the native bees Eucera fervens and other species were more abundant under agroecological management. Species of the categories analyzed (body size: small, medium, and large; nesting site: above-ground cavities or ground-nesting; and social behavior: solitary or social) were present on farms under both management types. We found that management type affected bees, and their effects differed among bees with specific biological traits. Medium-sized and small bees, ground-nesting bees, and solitary bees were found in greater abundance on agroecological farms than on conventional farms. Our data allowed us to explain the diversity and abundance of bees relative to the management type and biological traits of the species. Implications for insect conservation: This study suggests that incorporating biodiversity-based management strategies might increase abundance and richness of native bees with different biological traits, ensuring the free pollination service they provide and a taxonomically and functionally diverse assemblage.

Management of perennial forbs sown with or without self‐regenerating annual clovers for forage and nectar sources in a low‐input dryland production system

AbstractForage systems can be designed to produce high quality feed for ruminant livestock while providing habitat for insect pollinators. We compared forage productivity, nutritive value, and selenium uptake as well as late summer nectar production of perennial forage species; alfalfa (Medicago sativa), birdsfoot trefoil (Lotus corniculatus), red clover (Trifolium pratense), sainfoin (Onobrychis viciifolia), and chicory (Cichorium intybus) as monocultures and intercropped with either subterranean clover (Trifolium subterraneum) or balansa clover (Trifolium michelianum) for two successive years in Oregon. Red clover intercropped with balansa clover out‐performed other stands, producing over 11 t DM ha−1 in 2019 and 9.4 t DM ha−1 in 2020. Birdsfoot trefoil and sainfoin mixtures were dominated by subterranean clover, negatively affecting total forage yield and flower abundance. Chicory intercropped with subterranean clover formed a more balanced mixture with improved DM yield and nutritive value relative to chicory monocultures. Chicory was most responsive to Se‐fertilisation in both years, having a higher concentration of Se relative to the other perennial species. Chicory also had high levels of condensed tannins (18.1–43.3 mg/g DM) relative to the other forages (1.8–17.5 mg/g DM). Red clover had the most consistent bloom in 2019, with 170 inflorescences per square meter at peak bloom and yielded an estimated total of 16.9 kg ha−1 sucrose. Birdsfoot trefoil produced the most inflorescences during peak bloom in 2020 at 279 inflorescences per square meter. However, alfalfa had a higher estimated sucrose yield in 2020 at 241 kg ha−1.

FEATURES PRODUCTIVITY FORMATION OF RED-FLESH APPLE VARIETIES

In the changing conditions of Transcarpathia, red-soft varieties provide high productivity and are less affected by diseases, which will provide a biologically clean technology for their cultivation. Most apples of red pulp varieties at first glance do not differ from the total weight of the fruit. Era apples do not have an intense skin color, but an intense color of the pulp. Fruits of Siren, Odysio, Baia Marissa red with different intensity of placement of lentils and rusting with white edging. Assessing the structure of the flower, it should be noted that almost each has additional pistils and highly developed anthers, which promotes self-pollination. All varieties are characterized by dark pink flowers with very abundant flowering. Rings are formed not only on short biennial branches, but also annual, which should be taken into account when pruning and normalization of flowering. Among the studied varieties, the Baia Marisa variety is the tastiest and with an intense color. It has a red flesh color due to the presence of a special pigment "anthocyanin", which destroys harmful bacteria in the human body and strengthens the immune system. The amount of anthocyanins is 2 times higher than in ordinary apples. Therefore, we offer it for widespread implementation in the production of dietary food. Assessing the economic and biological indicators, it is established that the load on the trees of the third and fourth year of fruiting is quite high with the formation of high quality apples in spite of the critical conditions of 2020. The average number of fruits per tree was up to 60 apples weighing from 188 to 203 g, which provided a high yield of Baia Marisa 33.7 t/ ha in 2019 and the lowest in 2020 30.5 t / ha. The lowest yield in 2019 was characterized by the Odisio variety, which yielded only 29.8 t / ha against 31.2 t / ha in 2020. Measuring biometric indicators, the required height of trees in the fourth year of vegetation was established. The height of the trees of the studied varieties was about 300 cm, except for the variety Sirena, whose trees reached an average of no more than 285 cm in 2019 and an increase in height by 20-25 cm in 2020. The diameter of the trunk is the best in the variety Sirena (232 mm) with the best growth during the year. In terms of the number of annual shoots, the Era variety is in the lead (58 pieces) and the average length of annual growth is 61 cm in two years of comparative evaluation. In difficult climatic conditions, new varieties with red crumbs stood out, the yield of which averaged over the above period 30t / ha of high quality fruit, which provided a selling price of 45-64 UAH. The level of profitability from the cultivation of these varieties was 167 256%. Efficiency indicators depended on the form of product delivery, sales and time of maximum sales. Such products are designed for sale in gift packaging with juices during the Christmas holidays, sale to restaurants for culinary decoration of meat and desserts. Keywords: apple tree, red pulp varieties, productivity, economically valuable traits, economic efficiency

Flowering Phenology of Shrub Roses as a Sensitive Indicator of Meteorological Variability in Central Europe

Abstract Climate change and warming affect the development cycle of ornamental plants and, thus, their quality and ornamental value. The study aimed to investigate the flowering phenology of 37 cultivars of shrub roses in response to meteorological conditions based on eight years of observations. Based on 14,800 field records, we grouped shrub rose cultivars according to their dominant flowering stage as a sensitive indicator of variability in weather conditions. We also selected the rose cultivars that would retain the highest ornamental value even at increasing temperatures. The total flowering duration of the cultivars ranged from 31 to 115 days (mean 90.4 days) and was significantly positively correlated with temperature. Meteorological conditions significantly influenced individual flowering stages (FS) and a trend of changes concerning the long-term gradient was observed: the increase in temperature extended FS10 and shortened FS25, FS50, and FS75 but did not affect FS100. If the warming trend continues, the abundant flowering of roses may be shortened considerably. Rose cultivars with the longest flowering period at FS10 abundance may adapt better to rising temperatures, and, therefore may be more useful in landscape planning and management.

Forest restoration treatments indirectly diversify pollination networks via floral- and temperature-mediated effects.

In North American conifer forests, a variety of federally initiated thinning programs are implemented to restore pre-European settlement forest structures, but these changes may impact ecosystem function via impacts on sensitive biotic communities. Across the wildland-urban interface of the Front Range region of Colorado, agencies associated with the Collaborative Forest Landscape Restoration Program (CFLRP) have implemented thinning treatments across thousands of hectares of ponderosa pine forest; here we leverage these treatments as an experimental framework to examine thinning effects on a pollinator community. We measured variation in forest structure and sampled bee community assemblages using multiple methods (trapping and netting) to compare bee biodiversity and patterns of floral visitation by bees (bee-flower networks) between mechanically thinned stands that were 3-10 years after treatment and nonthinned stands. Three key findings emerged: (1) Native bee abundance, richness, and diversity were 120%, 53%, and 37% greater, respectively, in thinned stands. In addition, nestedness, richness, and abundance of bee-flower interactions were all substantially higher in thinned stands, and there was increased functional redundancy in bee assemblages after thinning. (2) Structural equation modeling indicated that variation in temperature and floral abundance were mediated by canopy openness and correlated with bee richness and abundance, thereby indirectly driving variation in bee-flower interactions. (3) Four floral species (Penstemon virens, Cerastium arvense, Erysimum capitatum, and Geranium caespitosum) were identified as key connectors in bee-flower interaction networks, though these were not necessarily the most abundant flowering plants. Our analyses indicate that native bee α-diversity and bee-flower interactions positively responded to thinning treatments, and these effects were indirectly driven by canopy removal. We conclude that CFLRP treatments have conservation value for native bee communities. Further monitoring is warranted to evaluate the longevity of these effects.