Inflorescence Formation Research Articles

LED lighting as an effective tool for regulating plant morphogenesis

The results of studying the effect of light with different spectral composition on the morphogenesis of wild-type of Arabidopsis thaliana (Col 0), as well as wei8-1tar1-1 and ahk2 mutants with modified signal transduction processes of auxins and cytokinins. We used a specially developed technique that simplifies the assessment of the effect of light on the growth and development of A. thaliana plants, especially the configuration of their root system during the entire growing season. Luminescent (LL) and light-emitting diode (LED) light sources were used, which made it possible to vary the physiologically significant blue (B), green (G), red (R), and far red (FR) spectral ranges. The R/B ratio was equal to 1 and 4 for LED 1 and LED 2 lighting options, respectively, at the same total flux density of B and R light photons. The ratios of R/FR and B/G in the spectra of LED illumination varied in the ranges closest to those observed in natural conditions. The most effective for the formation of the root system, rosette of leaves and inflorescences of A. thaliana (Col 0) was LED illumination with R/B = 4, B/G = 1 and R/FR = 6. The obtained data indicate an important role of AHK2 histidine kinase receptors in stimulation of the formation of vegetative organs of A. thaliana in response to an increase in the level of R and a decrease in B light (an increase in the R/B ratio) in complex spectral compositions. At the same time, LED lighting with a higher level of B and a low level of R light (R/B = 1, B/G = 2 and R/FR = 3) rather effectively stimulated the accumulation of the dry mass of the root system and the formation of inflorescences compared to fluorescent lighting. Stimulation of root growth by light of this spectral composition is probably mediated by a significant increase in the level of endogenous auxins. The decrease in the R/FR ratio in the spectrum of LED sources compared to the fluorescent lamp contributed to the stimulation of flowering of A. thaliana, regardless of the nature of the mutation and despite other differences in the spectral composition.

The Use of Compost from Post-Consumer Wood Waste Containing Microbiological Inoculums on Growth and Flowering of Chrysanthemum (Chrysanthemum × grandiflorum Ramat./Kitam.)

The purpose of the conducted study was to assess the possibility of using composts made from post-consumer wood containing waste of fibre boards and microbiological inoculums in chrysanthemum (Chrysanthemum × grandiflorum Ramat./Kitam.) ‘Jewel Time’ cultivation. Five variants of composts (marked ask, KK, AL, AL + K, EM, EM + K) were prepared, each variant was duplicate. All variants consisted of fibreboard waste (60% of its weight), mixed with mature compost made from fibreboard waste (30%), Protohumovit-biologically active organic fertilizer with the chemical composition of cattle manure (3%), starch, sugar, corn oil (together 7%). A biological inoculum “Activit Las” was added to one half of reactors. “Activit Las” (produced by Atlas Planta S.C, Bydgoszcz) is biological inoculum containing of selected bacteria, actinobacteria and fungi, that is intended to accelerate the composting of lignocellulosic materials, including wood from forest and sawmill. The second part of reactors was implemented by microbiological inoculum (EM) from Greenland Technologia EM (Trzcianki, Poland). A Bio Best (produced by Atlas Planta S.C, Bydgoszcz) formulation of chicken manure was added to some of the reactors containing EM and Activit Las. Compost without any additional microorganisms and microelements was control for experiment. Plant quality depended on the dose of compost used as well as on the type of microbial inoculations used during the composting process. The addition of composts containing the EM microbial inoculation to peat stimulated the formation of inflorescences and inflorescence buds. It also had a positive effect on the size and number of leaves. An additional effect of using compost obtained from wood waste is the reduction in the consumption of natural resources such as peat.

The demise of Monechma: new combinations and a new classification in the resurrected genera Meiosperma and Pogonospermum (Acanthaceae)

SummaryRecent molecular phylogenetic results have demonstrated that Monechma s.l., a group of plants with ecological importance in the savanna and succulent biomes of sub-Saharan Africa, is polyphyletic with two discrete lineages recognisable. In the present work, we recognise Monechma Groups I and II at the generic rank, which can be distinguished by differences in inflorescence characteristics and seed morphology. The nomenclatural implications of these findings are investigated. The lectotype of Monechma, M. bracteatum Hochst., is a part of a small lineage of plants closely allied to Justicia L. sect. Harnieria (Solms) Benth. for which the earliest valid name is found to be Meiosperma Raf. Hence, Monechma is synonymised within Meiosperma, which comprises six accepted species and two undescribed taxa. The majority of species of former Monechma s.l. are resolved within the second lineage for which the only validly published generic name is Pogonospermum Hochst. This resurrected genus comprises 34 accepted species plus two undescribed taxa. Pogonospermum displays considerable morphological variation and is here subdivided into six sections based primarily on differences in plant habit, inflorescence form, calyx, bract and bracteole venation, and seed indumentum. The new combinations and new sections are validated, and seven accepted species names are lectotypified.

Effect of low glyphosate doses on flowering and seed germination of glyphosate-resistant and -susceptible Digitaria insularis.

Herbicide hormesis is characterized by stimulation of various growth and developmental parameters, such as biomass and height, at low herbicide doses. Other possible hormetic effects are earlier flowering, higher seed weight, more seeds, and a shorter plant life cycle, which could favor the propagation of the species. This study tested the early flowering in glyphosate-resistant and -susceptible Digitaria insularis biotypes under treatment with low glyphosate doses. Hormesis caused by low glyphosate doses occurred in all experiments. The hormetic effects were a decrease in time necessary for the formation of inflorescences and increased seed weight and germination speed. Higher glyphosate doses were required for the hormetic effect in the glyphosate-resistant than the -susceptible D. insularis biotype. Hormesis caused by low glyphosate doses in D. insularis may provide an advantage for the dissemination of this species, helping to alter the weed flora. As the doses that cause stimulation in glyphosate-resistant biotypes are higher than in glyphosate-susceptible biotypes, the selection of resistant biotypes may be favored in glyphosate-sprayed fields, increasing the rate of infestation of glyphosate-resistant biotypes.

Response and Ability of the Vines of Cultivar Storgozia to Recover after Hail Damage

A study was performed to determine the response and the ability to recover cultivar Storgozia after the extreme meteorological phenomenon mesocyclone registered in May 2018, accompanied by intense hail and hurricane wind. The hail damage impact on the actual fertility elements, the growing strength and the degree of shoots ripening, the yield quantitative and qualitative indicators, and the grape's chemical composition had been determined for the achieving of the objective. The study found that the damages by hail on the green parts of the vine in 2018 did not have a negative impact on the process of formation of inflorescences in the winter eyes and did not affect the vine productivity of cv. Storgozia in the following year. The damages caused by hail at the beginning of the growing season had little effect on the growing strength and the degree of shoot ripening. The leaves and leaf area (1.36 m2) of the main shoots are proven to be smaller in size in the year with hail, compared to the other two years, which reflects on the size of the leaves (3.38 m2) and leaf area of the lateral shoots, which are proven to be larger after the registered hail. The total leaf area per vine had remained almost the same in all three years, as the difference was only in the leaf area ratio of the main and lateral shoots in 2018 that did not result in disruption of the vital for the vine plant physiological and biochemical processes in the leaves. Hail had a considerable negative effect on the structure of the cluster, the berry size, the yield per vine. The overall assessment of the quality of the grapes from the three harvests shows that with varying degrees of evidence for the individual indicators, hail has a significant adverse effect on its chemical composition in terms of sugar, titratable acids, anthocyanins, and phenolic compounds.

Comparative Genome Analysis of Genes Regulating Compound Inflorescences in Tomato.

Inflorescences are the main factor affecting fruit yield. The quantity and quality of inflorescences are closely related to fruit quality and yield. The presence of compound inflorescences in cherry tomatoes is well established, and it has been discovered by chance that compound racemes also exist in tomatoes. To explore the formation of compound inflorescences in tomato, transcriptome sequencing was performed on Moneymaker (MM) and Compound Inflorescence (CI) plants. In-florescences were collected in three periods (early, middle and late) in three replicates, for a total of 18 samples. Data analysis showed that the DEGs were most enriched in metabolic pathways and plant hormone signal transduction pathways. The DEGs were also enriched in the cell cycle pathway, photosynthesis pathway, carbon metabolism pathway and circadian rhythm pathway. We found that the FALSIFLORA (FA), COMPOUND INFLORESCENCE (S) and ANANTHA (AN) genes were involved in compound inflorescence development, not only revealing novel genes but also providing a rich theoretical basis for compound inflorescence development.

Molecular Characterization and Expression Patterns of the HkSVP Gene Reveal Distinct Roles in Inflorescence Structure and Floral Organ Development in Hemerocallis fulva.

SHORT VEGETATIVE PHASE (SVP) genes are members of the well-known MADS-box gene family that play a key role in regulating vital developmental processes in plants. Hemerocallis are perennial herbs that exhibit continuous flowering development and have been extensively used in landscaping. However, there are few reports on the regulatory mechanism of flowering in Hemerocallis. To better understand the molecular basis of floral formation of Hemerocallis, we identified and characterized the SVP-like gene HkSVP from the Hemerocallis cultivar ‘Kanai Sensei’. Quantitative RT-PCR (qRT-PCR) indicated that HkSVP transcript was mainly expressed in the vegetative growth stage and had the highest expression in leaves, low expression in petals, pedicels and fruits, and no expression in pistils. The HkSVP encoded protein was localized in the nucleus of Arabidopsis protoplasts and the nucleus of onion epidermal cells. Yeast two hybrid assay revealed that HKSVP interacted with Hemerocallis AP1 and TFL1. Moreover, overexpression of HkSVP in Arabidopsis resulted in delayed flowering and abnormal phenotypes, including enriched trichomes, increased basal inflorescence branches and inhibition of inflorescence formation. These observations suggest that the HkSVP gene may play an important role in maintaining vegetative growth by participating in the construction of inflorescence structure and the development of flower organs.

K. V. KLEMESHOVA, T. YU. GABUEVA PECULIARITIES OF FORMATION OF LARGE-FLOWERED CHRYSANTHEMES FOR OBTAINING CUT IN A WET SUBTROPICAL CLIMATE

Chrysanthemum is one of the leading crops of commercial floriculture. Within garden groups and classes, chrysanthemums are divided according to cultivation methods, shape and size of the inflorescences. For varieties grown on a cut, a group of large-flowered (with a diameter of inflorescences of 12-25 cm), small-flowered (4-10 cm) chrysanthemums and santini (from 2 to 4 cm) is distinguished. Having a limited assortment of chrysanthemum garden, in a humid subtropical climate, it is possible to form a largeflowered (single-headed, disbud) and small-flowered (spray) cut. The purpose of the research was to study the peculiarities of formation of large-flowered chrysanthemums (Chrysanthemum×hortorum Bailey) to obtain cut in the humid subtropics of Russia. The objects of research were large-flowered and small-flowered varieties of chrysanthemums of foreign and domestic breeding. The studies were carried out in the open ground of the Department of Agricultural Engineering and Nursery of the Federal Research Center the Subtropical Scientific Center of the Russian Academy of Sciences. Scientific research was carried out according to the methodology of State variety testing of agricultural crops and the methodology of testing for distinctness, uniformity and stability of chrysanthemum (perennial) Chrysanthemum spec. ‘Sevan’, ‘Baltica White’, ‘Granada’ and ‘Zembla Brasil’ are large-flowered varieties, which have bush peduncles of good commercial quality with large inflorescences of saturated shades. In turn, from small-flowered garden forms ‘Zembla White’, ‘Annecy White’ and ‘Westland Regal’ with regular pinching, you can grow a large-flowered cut of chrysanthemums. It was revealed the relationship between biometric characteristics in order to determine additional diagnostic features of the possibility of the formation of large-flowered inflorescences. So, the diameter of the inflorescence is the most significant parameter for research which has significant positive relationships with the diameter of the peduncle and the length of the extreme ray flower. It will allow determining the possibility of growing the variety in one form or another, depending on the needs of production, at the initial stages of introduction and variety study.

HvLEAFY controls the early stages of floral organ specification and inhibits the formation of multiple ovaries in barley.

Transition to the reproductive phase, inflorescence formation and flower development are crucial elements that ensure maximum reproductive success in a plant's life cycle. To understand the regulatory mechanisms underlying correct flower development in barley (Hordeum vulgare), we characterized the multiovary 5 (mov5.o) mutant. This mutant develops abnormal flowers that exhibit mosaic floral organs typified by multiple carpels at the total or partial expense of stamens. Genetic mapping positioned mov5 on the long arm of chromosome 2H, incorporating a region that encodes HvLFY, the barley orthologue of LEAFY from Arabidopsis. Sequencing revealed that, in mov5.o plants, HvLFY contains a single amino acid substitution in a highly conserved proline residue. CRISPR-mediated knockout of HvLFY replicated the mov5.o phenotype, suggesting that HvLFYmov5 represents a loss of function allele. In heterologous assays, the HvLFYmov5 polymorphism influenced protein-protein interactions and affinity for a putative binding site in the promoter of HvMADS58, a C-class MADS-box gene. Moreover, molecular analysis indicated that HvLFY interacts with HvUFO and regulates the expression of floral homeotic genes including HvMADS2, HvMADS4 and HvMADS16. Other distinct changes in expression differ from those reported in the rice LFY mutants apo2/rfl, suggesting that LFY function in the grasses is modulated in a species-specific manner. This pathway provides a key entry point for the study of LFY function and multiple ovary formation in barley, as well as cereal species in general.

Comparative transcriptome analysis of a fan-shaped inflorescence in pineapple using RNA-seq

Pineapple plant usually has a capitulum. However, a fan-shaped inflorescence was exceptionally evolved in pineapple, having multiple crown buds. In order to reveal the molecular mechanisms of the formation of the fan-shaped inflorescence, fruit traits and the transcriptional differences between the fan-shaped inflorescence and the wild-shaped inflorescence pineapples were analyzed in three tissues, i.e., the flower stem apex, the base of the inflorescence, and the inflorescence axis. The weight (i.e., individual yield) of fan-shaped fruit is 4.5 times that of wild-shaped fruit；and non-significant difference in soluble solids, soluble sugar, titratable acid, and Vitamin C was found. Between the fan-shaped inflorescence and wild-shaped inflorescence, a total of 5370 differentially expressed genes were identified across the three tissues. Of these genes, there were 489 overlapping differentially expressed genes in all three tissue comparisons. Between the two pineapples, functional analysis indicated that 444 transcription factors and 206 inflorescence development-related genes were differentially expressed in at least one tissue comparison, while 45 transcription factors and 21 inflorescence development-related genes were overlapped across three tissues. Among the 489 overlapping differentially expressed genes in the three tissue comparisons, excluding the inflorescence development-related genes and transcription factors, 80 of them revealed a higher percentage of involvement in the biological processes relating to response to auxin, and reproductive processes. RNA-seq value and real-time quantitative PCR analysis exhibited the similar gene expression patterns in the three tissues. Our result provided novel cues for understanding the molecular mechanisms of the formation of the fan-shaped inflorescence in pineapple, making a valuable resource for the study of plant breeding and the speciation of pineapple.

A Taxonomic Revision of the Genus Poeppigia (Fabaceae: Dialioideae)

Poeppigia is a Neotropical genus of legumes that occurs from Mexico and Cuba to eastern Brazil and is considered until now to be monospecific with two varieties. Being one of the 17 genera in the subfamily Dialioideae, Poeppigia stands out as one of the few genera with not reduced perianth and androecium, representing a possible link between this subfamily and the other Fabaceae. The genus was never revised since several taxa were described in the XIX century and lack of recent studies and proper typification. Here we revised the genus taxonomically with the analysis of more than 400 specimens and proposed the acceptance of two species: P. procera, distributed on tropical forests from Mexico to Amazon and Southeast Brazil and P. densiflora, endemic of Brazilian Caatinga. The two species are distinct for many characters as habitus, size of branch, leaf and fruits, number of leaflets, stipules and bracts and form of inflorescence. Seed, embryo, pollen and seedling descriptions, conservation assessments, illustrations, maps of distribution and an identification key are presented. Nomenclatural, biogeographical, and ecological comments and three new lectotypifications are made.

Use of growth regulator in reducing the size of Sesbania punicea (Cav.) Benth.

Sesbania punicea (Cav.) Benth. is a species with ornamental potential, highlighted by the orange color of the flowers and the formation of inflorescences in racemes. Because it is a native species and few plant breeding information, studies are needed to be used commercially, one of the aspects to be investigated is the reduction of its size for potting. The objective was to evaluate the influence of daminozide in reducing the size of Sesbania punicea. The seedlings were grown in 2.8 L pots containing substrate based on pine bark. A completely randomized design was used, with 3 treatments, 1 control, with 4 replications, 5 plants per plot. The treatments consisted of daminozide in doses of 2, 4 and 6 g L⁻¹ and control (water + 1 mL L⁻¹ adhesive spreader) that were sprayed using a 2 L accumulated pressure sprayer on the plants on the 22nd and 44th days after transplant. At the end of the experiment, height, stem diameter, dry matter of shoot and roots, chlorophyll a, b and total, number of leaves and internodes were evaluated. There were significant differences for plant height, stem diameter, number of leaves per plant and shoot dry matter. It is concluded that the dose of 5.8 g L⁻¹ of daminozide showed superior results for the reduction the size of this species.

A Systematic Approach to Agastache mexicana Research: Biology, Agronomy, Phytochemistry, and Bioactivity.

Mexico is the center of origin of the species popularly known as toronjil or lemon balm (Agastache mexicana Linton & Epling). Two subspecies have been identified and are commonly called purple or red (Agastache mexicana Linton & Epling subspecies. mexicana) and white (Agastache mexicana subspecies xolocotziana Bye, E.L. Linares & Ramamoorthy). Plants from these subspecies differ in the size and form of inflorescence and leaves. They also possess differences in their chemical compositions, including volatile compounds. Traditional Mexican medicine employs both subspecies. A. mexicana exhibits a broad range of pharmacological properties, such as anti-inflammatory, anxiolytic, and antioxidant. A systematic vision of these plant’s properties is discussed in this review, exposing its significant potential as a source of valuable bioactive compounds. Furthermore, this review provides an understanding of the elements that make up the species’ holistic system to benefit from lemon balm sustainably.

Productivity of medicinal raw materials by different genotypes of Matricia chammomila L. is affected with pre-sowing radiation exposure of seeds

One of the key tasks of modern pharmacology is complete and diverse use of natural raw materials - microorganisms and plants. So, different approaches of metabolism redirection were applied. Studying of plant protective reactions indicated a possibility to use various stress factors for the metabolism reorientation. One of the most effective approaches is to use ionizing and UV-C exposure. Thus, there is a shift in metabolic processes towards the formation of secondary metabolism substances with antioxidant, anticancer, immunomodulatory and anti-inflammatory effects. Biotechnological use of radiation exposure is based on the systemicity of radiobiological reactions, including protective and adaptive reactions in non-exposed organs («abscopal effect») and even in non-exposed organisms that are found in the same environment as exposed ones («by stander effect»). The products synthesized in these structures are some medicine materials and directly used by human. Radiation exposure affects developing, blocking of primary and secondary metabolism, so must be improved the selection of varieties with initial high productivity of medicinal raw materials, the choice of exposure and optimal doses inducing an increasing yield of the target metabolite and do not reduce the yield of medicinal raw materials. Effect of UV-C and X-ray pre-sowing exposure of seeds to the productivity of inflorescence formation of eight genotypes of Matricia chammomila L. was studied. There were indicated genotypes with increasing yield of inflorescence only under one or two exposure types and the variety with stimulation of flowering under UV-C exposure and absence of the marker under X-ray one.

Studies of Vegetative Growth, Inflorescence Development and Eco-Dormancy Formation of Abscission Layers in Streptocarpus formosus (Gesneriaceae)

Streptocarpus formosus (Hilliard & B.L. Burtt) T.J. Edwards is a flowering herbaceous perennial indigenous to South Africa and is part of the rosulate group of herbaceous acaulescent plants within the Gesneriaceae family. According to the National Assessment database for the Red List of South African Plants version 2020.1., the plant is listed as rare. The ornamental use of S. formosus has untapped commercial potential as a flowering indoor pot plant, an outdoor bedding plant for shade and as a cut flower for the vase, all of which are limited by a five-month eco-dormancy period during the late autumn and all through the cold season in the short-day winter months. Viable commercial production will require cultivation techniques that produce flowering plants all year round. This study investigated the effectiveness of applying root zone heating to S. formosus plants grown in deep water culture hydroponics during the eco-dormancy period in preventing abscission layer formation and in encouraging flowering and assessed the growth activity response of the plants. The experiment was conducted over eight weeks during the winter season in the greenhouse at Kirstenbosch Botanical garden in water reservoirs, each maintained at five different experimental temperature treatments (18, 22, 26—control, 30 and 34 °C) applied to 10 sample replicates. The results showed that the lowest hydroponic root zone temperature of 18 °C had the greatest effect on the vegetative growth of S. formosus, with the highest average increases in fresh weight (1078 g), root length (211 cm), overall leaf length (362 cm) and the number of newly leaves formed (177 = n), all noted as statistically significant when compared with the other water temperature treatments, which yielded negative results from reduced vegetative growth. Findings from the study also revealed that while all heated solutions significantly prevented the formation of abscission layers of S. formosus, they had a less significant effect on inflorescence formation, with only 18 °C having the greatest positive effect on flower development.

Improving architectural traits of maize inflorescences

The domestication and improvement of maize resulted in radical changes in shoot architecture relative to its wild progenitor teosinte. In particular, critical modifications involved a reduction of branching and an increase in inflorescence size to meet the needs for human consumption and modern agricultural practices. Maize is a major contributor to global agricultural production by providing large and inexpensive quantities of food, animal feed, and ethanol. Maize is also a classic system for studying the genetic regulation of inflorescence formation and its enlarged female inflorescences directly influence seed production and yield. Studies on the molecular and genetic networks regulating meristem proliferation and maintenance, including receptor-ligand interactions, transcription factor regulation, and hormonal control, provide important insights into maize inflorescence development and reveal potential avenues for the targeted modification of specific architectural traits. In this review, we summarize recent findings on the molecular mechanisms controlling inflorescence formation and discuss how this knowledge can be applied to improve maize productivity in the face of present and future environmental challenges.

Morphology, Physiology and Analysis Techniques of Grapevine Bud Fruitfulness: A Review

Grapevine reproductive development extends over two growing seasons (vegetative cycles), for the complete formation of inflorescences and clusters. Induction and floral differentiation, the mechanism that leads to the formation of reproductive structures inside dormant buds, is a complex process divided into three well-defined stages (formation of anlagen, inflorescence primordia and flowers). This sequence of stages comprises morphological, biochemical, and physiological events, influenced by a set of environmental and endogenous factors. Inflorescence primordia formation determines the potential number of clusters that will be formed in the following growing season. Thus, during bud dormancy, viticulturists and winemakers can obtain a first yield prediction through the determination of bud fruitfulness. This information allows adjustments to be made to bud load, promoting balanced yield and fruit quality and higher commercial value. The present review describes the morphology and physiology of the formation of inflorescence primordia, as well as discusses the main abiotic and biotic factors involved, including a physiological disorder known as primary bud necrosis. In the same way, we intend to approach the more used techniques of analysis of fruitfulness and its importance for a robust yield forecasting.

Neera, a non-fermented traditional drink from coconut spadix restores the redox status in sodium fluoride intoxicated mice.

Neera, non-fermented coconut inflorescence sap (NFCIS) and its fermented form, toddy (FCIS) are the two well-known traditional drinks in South India. Both the saps show high rejuvenation effect and NFCIS is used for the curing of bronchial suffocation, anemia, tuberculosis and piles in traditional medicine. But, a few scientific studies have been reported on their health benefits so far. Presently, the antioxidant effect of both non-fermented (NFCIS) and fermented form (FCIS) of coconut inflorescence were analyzed in experimental animals. The free radical scavenging property of FCIS and NFCIS was analyzed in vitro. The effect of these saps on mitigating sodium fluoride (NaF) deteriorated redox status was evaluated in mice. NFCIS exhibited high antioxidant activity than its fermented form. NFCIS reduces metal ions and scavenge hydroxyl and DPPH radicals with IC50 values 6.5±1.9 and 44±3.14µL/mL, respectively. Supplementation of NFCIS for 14 days increased SOD, CAT and GPx activities and GSH level in liver by 51.67, 52, 27.88 and 35.77%, respectively against NaF induced decline with a concomitant decrease in lipid peroxidation to 40.76%. Saps rich in minerals indicate pharmaceutical and nutritional value. The study revealed the antioxidant efficacy of non-alcoholic natural drink, Neera and recommends an alternative for synthetic carbonated soft drinks. The regular consumption of Neera may protect the body from various chronic diseases especially where the oxidative stress played as a key role.

RESEARCH OF DEVELOPMENT OF BUDS OF SOME ROSE VARIETIES FROM THE FLORIBUNDA GROUP UNDER THE CONDITIONS OF APSHERON

The article provides data on the development of buds of some of rose varieties: ‘Cyclamen’, ‘Lilli Marlene’, ‘Masquerade’, ‘Nordia’, ‘Pink Wonder’ from the floribunda group in subtropical conditions of Absheron. As a result of the conducted studies, it was revealed that the studied roses during the growing season have three to four periods of shoot formation, providing three to four times flowering. It was revealed that in autumn the natural end of the growing season is not observed. The buds of roses, depending on their location on the shoot, go into winter in varying degrees of development and behave like their evergreen ancestors, i.e. subtropical species. The upper buds on the annual shoot are the most developed, and in most of them flower differentiation is observed. In spring, differentiation of flower buds begins very early and depends on weather conditions. The buds laid down in the lower part of the shoot remain dormant until the spring of the next year, and after pruning begin to develop as generative. The development of generative shoots from renewal buds in spring is the longest. And the development of sylleptic shoots proceeds as follows: after the beginning of the inflorescence protrusion, two or three auxiliary buds located in the upper part of the generative shoot begin to develop as flowering. Observations have shown that under the conditions of Absheron, the period from the appearance of buds to flowering in floribunda roses lasts longer than in varieties of other groups, which is explained by the formation and development of inflorescences with a large number of flowers. As a result of a detailed study of the biology of bud development in floribunda roses under the conditions of Apsheron, it was found that the onset of bud differentiation and the duration of the stages of organogenesis largely depend on weather conditions. In addition, these varieties of roses do not have a dormant winter period, which is forced.

Reproductive phenology of Uspí tree Couepia polyandra (Kunth) Rose (Chrysobalanaceae) in Campeche, Mexico

Objective. To describe reproductive phenological stages, since the formation of flower buds, flowering, fruiting, up to the formation of the ripe fruit and foliation of 21 Couepia polyandra trees; and correlation of allometric data of tree height, diameter at breast height (DBH) and crown diameter, as well as the correlation of precipitation with reproductive phenology data. Methodology. The description of the reproductive phenology (foliage, formation of flower buds, flowers, fruits) was done by direct monthly observation with a digital camera (Canon SX60HS, 65). The correlation among precipitation, allometry, and types of soils where the trees grow was calculated by recording data from each tree by measuring height, diameter at breast height (DBH) and foliage. Results. The highest tree was 21.0 m; the widest DBH measured 68 cm; and the greater crown diameter was 34.45 m; the overall averages were 10.38 m, 33.17 cm and 9.37 m, respectively. A significant correlation was found between height and DBH (r=0.91, p<0.05); the correlations for the variables Height-Crown and DBH-Crown were not significant (p>0.05). Conclusions. Water as a factor is responsible for the formation of inflorescence and fruit; determining that these phenological events are dependent variables with precipitation, highlighting a mean positive relation with the growth of flowers.