Vegetative Reproductive Organs Research Articles

POTENTIAL WEED INFESTATION OF SOIL IN DIFFERENT TECHNOLOGIES OF CROP CULTIVATION

Исследования проводили с целью определения эффективности разных технологий возделывания культур в управлении потенциальной засорённостью пахотного слоя дерново-подзолистой глееватой среднесуглинистой почвы в условиях Ярославского региона. Работу выполняли в 2021–2022 гг. Исследования проводили на трёх системах основной обработки почвы – отвальной, поверхностно-отвальной и поверхностной, по четырём системам удобрений – без удобрений, солома 3 т/га, солома 3 т/га + NPK, NPK, а также по двум системам защиты растений от сорняков – без гербицидов и с гербицидами. Для расчётов использовали усреднённые по системам основной обработки почвы, удобрений и защиты растений данные. Исходное содержание семян сорных растений в момент закладки опыта (1995 г.) составляло 217,8 млн шт./га. К 2022 году произошло увеличение количества генеративных органов размножения сорняков приблизительно в 2,5 раза (на О1 – 549,9 млн шт./га; О3 – 539,9 млн шт./га). В настоящее время на опытном поле в структуре сорного компонента агрофитоценоза преобладают малолетние виды, за счёт уменьшения количества многолетних видов, которые преобладали на момент закладки опыта. За период 2001–2022 гг. наблюдалось уменьшение длины вегетативных органов размножения сорных растений в 24,0 раза на отвальной системе обработки (в 2001 г. – 410,2 см/м2, в 2022 г. – 17,1 см/м2) и 15,7 раза – на поверхностно-отвальной системе обработки (в 2001 г. – 431,1 см/м2, в 2022 г. – 27,5 см/м2). Поверхностно-отвальная обработка почвы способствует очищению пахотного горизонта от органов генеративного и вегетативного размножения на уровне отвальной. Органические и минеральные удобрения оказывали неоднозначное влияние на потенциальную засорённость почвы. Воздействие гербицидных обработок на банк семян и запасы вегетативных органов размножения сорных растений в почве не выявлено. The researches were conducted in order to determine the effectiveness of different crop cultivation technologies in managing the potential weed infestation of the arable layer of soddy podzolic gleyic middle loamy soil in the conditions of the Yaroslavl region. The work was carried out in 2021–2022. The studies were carried out on three systems of the main tillage – moldboard, surface-moldboard and surface on four fertilizer systems – without fertilizers, straw 3 t/ha, straw 3 t/ha + NPK, NPK, as well as on two systems of plant protection against weeds – without herbicides and with herbicides. Data averaged over the systems of basic tillage, fertilizers, and plant protection were used for calculations. The initial content of weed seeds at the time of the trial establishment (1995) was 217.8 million pieces/ha. By 2022 there was an increase in the number of generative reproductive organs of weeds by approximately 2.5 times (by O1– 549.9 million pieces/ha; O3 – 539.9 million pieces/ha). At present young species prevail in the structure of the weed component of agrophytocenosis on the experimental field, due to a decrease in the number of perennial species that prevailed at the time of trial establishment. During the period 2001–2022 there was a decrease in the length of the vegetative reproductive organs of weeds by 24.0 times on the moldboard tillage system (in 2001 – 410.2 cm/m2, in 2022 – 17.1 cm/m2) and 15.7 times on the surface-moldboard tillage system (in 2001 – 431.1 cm/m2, in 2022 – 27.5 cm/m2). Surface-moldboard tillage contributes to the purification of the plough-layer from the organs of generative and vegetative reproduction at the level of the moldboard one. Organic and mineral fertilizers had an ambiguous effect on the potential weed infestation of the soil. The impact of herbicidal treatments on the seed bank and the reserves of vegetative reproductive organs of weed plants in the soil was not revealed.

Leaves and stolons transcriptomic analysis provide insight into the role of phytochrome F in potato flowering and tuberization.

Photoperiod plays a critical role in controlling the formation of sexual or vegetative reproductive organs in potato. Although StPHYF-silenced plants overcome day-length limitations to tuberize through a systemic effect on tuberigen StSP6A expression in the stolon, the comprehensive regulatory network of StPHYF remains obscure. Therefore, the present study investigated the transcriptomes of StPHYF-silenced plants and observed that, in addition to known components of the photoperiodic tuberization pathway, florigen StSP3D and other flowering-related genes were activated in StPHYF-silenced plants, exhibiting an early flowering response. Additionally, grafting experiments uncovered the long-distance effect of StPHYF silencing on gene expression in the stolon, including the circadian clock components, flowering-associated MADSs, and tuberization-related regulatory genes. Similar to the AtFT-AtAP1 regulatory module in Arabidopsis, the present study established that the AP1-like StMADS1 functions downstream of the tuberigen activation complex (TAC) and that suppressing StMADS1 inhibits tuberization invitro and delays tuberization invivo. Moreover, the expression of StSP6A was downregulated in StMADS1-silenced plants, implying the expression of StSP6A may be feedback-regulated by StMADS1. Overall, these results reveal that the regulatory network of StPHYF controls flowering and tuberization and targets the crucial tuberization factor StMADS1 through TAC, thereby providing a better understanding of StPHYF-mediated day-length perception during potato reproduction.

Full-length transcriptome-referenced analysis reveals crucial roles of hormone and wounding during induction of aerial bulbils in lily

Aerial bulbils are important vegetative reproductive organs in Lilium. They are often perpetually dormant in most Lilium species, and little is known about the induction of these vegetative structures. The world-famous Oriental hybrid lily cultivar ‘Sorbonne’, which blooms naturally devoid of aerial bulbils, is known for its lovely appearance and sweet fragrance. We found that decapitation stimulated the outgrowth of aerial bulbils at lower stems (LSs) and then application of low and high concentrations of IAA promoted aerial bulbils emergence around the wound at upper stems (USs) of ‘Sorbonne’. However, the genetic basis of aerial bulbil induction is still unclear. Herein, ‘Sorbonne’ transcriptome has been sequenced for the first time using the combination of third-generation long-read and next-generation short-read technology. A total of 46,557 high-quality non-redundant full-length transcripts were generated. Transcriptomic profiling was performed on seven tissues and stems with treatments of decapitation and application of low and high concentrations of IAA, respectively. Functional annotation of 1918 DEGs within stem samples of different treatments showed that hormone signaling, sugar metabolism and wound-induced genes were crucial to bulbils outgrowth. The expression pattern of auxin-, shoot branching hormone-, plant defense hormone- and wound-inducing-related genes indicated their crucial roles in bulbil induction. Then we established five hormone- and wounding-regulated co-expression modules and identified some candidate transcriptional factors, such as MYB, bZIP, and bHLH, that may function in inducing bulbils. High connectivity was observed among hormone signaling genes, wound-induced genes, and some transcriptional factors, suggesting wound- and hormone-invoked signals exhibit extensive cross-talk and regulate bulbil initiation-associated genes via multilayered regulatory cascades. We propose that the induction of aerial bulbils at LSs after decapitation can be explained as the release of apical dominance. In contrast, the induction of aerial bulbils at the cut surface of USs after IAA application occurs via a process similar to callus formation. This study provides abundant candidate genes that will deepen our understanding of the regulation of bulbil outgrowth, paving the way for further molecular breeding of lily.

Breaking the Dormancy of Snake's Head Fritillary (Fritillaria meleagris L.) In Vitro Bulbs-Part 1: Effect of GA3, GA Inhibitors and Temperature on Fresh Weight, Sprouting and Sugar Content.

Bulbs are the main vegetative reproductive organs of Fritillaria meleagris L. In nature, as well as in vitro, they become dormant and require low temperatures for further growth during the next vegetative period. In the present study, using 10 μM of gibberellic acid (GA3), or gibberellin biosynthesis (GA) inhibitors—ancymidol (A) and paclobutrazol (P)—the dynamic changes in soluble sugars, fructose and glucose content, fresh weight and sprouting capacity were investigated. F. meleagris bulbs were cultured on medium with GA3 and GA inhibitors for 1, 2 and 5 weeks at two different temperatures (24 and 7 °C). GA3 improved bulb fresh weight, as well as sprouting percentage at both tested temperatures, compared to the control. The highest fresh weight increase (57.7%) and sprouting rate (29.02%) were achieved when bulbs were grown at 24 °C for 5 weeks. In addition, soluble sugar content was the highest in bulbs grown for 5 weeks on medium supplemented with GA3. The main sugar in fritillary bulbs was glucose, while fructose content was lower. The sensitivity of bulbs to GA inhibitors differed and significantly affected sugar content in bulbs. To our knowledge, this is the first study of the sugar composition in F. meleagris bulbs during breaking of the bulb’s dormancy and its sprouting.

Mechanism of exogenous cytokinins inducing bulbil formation in Lilium lancifolium in vitro.

The cytokinin pathway promotes the initiation of bulbil formation, and iPA may an important type of cytokinin during bulbil formation in Lilium lancifolium. Bulbils are important vegetative reproductive organs in triploid Lilium lancifolium. We previously showed that cytokinins are involved in bulbil formation, but how cytokinins participate in bulbil formation is not clear. In this study, bulbil formation was divided into three stages on the basis of anatomical and histological observations: the bulbil initiation stage, bulbil primordium-formation stage and bulbil structure-formation stage. The results indicated that iPA was the most critical cytokinin during the bulbil initiation. qRT-PCR revealed that increased iPA content during bulbil initiation was mainly due to increased expression of cytokinin synthesis genes (IPT1/5) and cytokinin activation genes (LOG1/3/5/7) and significantly decreased expression of the cytokinin degradation gene CKX4. Exogenous 6-BA and lovastatin affected the cytokinin pathway and promoted or inhibited bulbil initiation by increasing or decreasing the content of endogenous iPA, respectively. In summary, we demonstrate that cytokinins positively regulate bulbil formation and provide preliminary insight into the regulatory mechanisms by which the cytokinin pathway promotes bulbil initiation.

Specificity of potential contamination of rice checks with weed seeds

Goal. To analyze the potential level of contamination of arable soil layer weed seeds and to establish the specificity of the changes in such reserves during the vegetation period of crops. The study was performed on rice checks of the Institute of rice of NAAS in the Kherson region in the 2017—2019 biennium.
 Methods. Research field, small and laboratory. To determine the factor of seeds and vegetative reproductive organs of weeds in certain soil horizons of rice fields per unit area (pieces/m2) was selected soil samples by the method of A. N. Kiseleva — twice per season, in spring and after harvest of rice. The arable soil was divided into three layers (10 cm each). To determine the viability of seeds used method of staining their tetrazoles. The results were compiled and analyzed.
 Results. A comparison of the level of potential contamination between horizons showed the highest number of weed seeds in the horizon of 0—10 cm on average, 16041 pieces/ m2, which is 47.6% of the overall presence of weeds in the soil (33650,2 pieces/ m2). In the soil horizon 10—20 cm the number of weed seeds reached 10489.2 pieces/m2, or 31.2% of the debris of the upper horizon. In the lower horizon of 20—30 cm level of the presence of weed seeds was low — 7119.8 pieces/ m2, which amounts to 21.2% from that of the top horizon of the soil. Among the weed species whose seeds were present in soil samples of the top horizon of 0—10 cm, the largest part was Kuga Astrakhantseva Scirpus mucronatus L. — 59.8%, in another place Boule seeds Kuga razveseloj Scirpus supinus L. — 31.8%, Polygonum Persicaria hydropiper L. percetage — 1004.7 pieces/ m2 (6,3%), chicken millet Echinochloa crus galli L. — 329.1 pieces/m2 (2.1%). Other types were less in the stocks of weed seeds.
 Conclusions. During the vegetation period inventory quantities of seeds of change and by autumn are increasing. The largest amplitude value of the stock of weed seeds is manifested in the upper 0—10 cm horizon of the arable layer and reaches to 12.3%. Qualitative and timely implementation of measures to protect rice crops from sowing to the presence of weeds provides a gradual reduction in the volumes of their Bank of seeds in the soil.

English

The present study includes two experiments; the physiological and the biotechnological experiments. The physiological experiment was designed to investigate the most interesting rare natural phenomenon of the development of vegetative reproductive organs (bulbils) in the inflorescence of tiger lily. In the other hand, the biotechnological experiment was carried out to evaluate the regeneration potential of bulbils culture in vitro. In the first experiment, the plants of tiger lily Lilium lancifolium var. Flore Pleno which were grown in greenhouse showed that the Pseudo viviparous phenomenon at the end of flowering when vegetative bulbils were induced in the inflorescence. These bulbils as pseudo viviparous structures were precisely formed in place of flowers and along the floral stalks. The flower head was completely surrounded by the extensive numbers of these bulbils; some of them continued in growth and produced new shoots. The tissue culture experiment of tiger lily var. Flore Pleno was carried out using bulbils culture for eight weeks of culture in vitro. The results indicate that the bulbils was shown to be a good choice as explants for micropropagation but the potential of these bulbils to produce  bulblets, shoots and roots was greatly influenced by the concentrations of naphthalene acetic acid (NAA) and  benzyl aminopurine (BA) in culture. However, the concentration of 1 mg/l BA combined with 0.1 mg/l NAA was shown to be the optimum for micropropagation of tiger lily var. Flore Pleno. Key words: Bulbils, pseudo viviparous phenomenon, tiger lily, in vitro, micropropagation, growth regulators.

Phenology of the oil palm interspecific hybrid Elaeis oleifera × Elaeis guineensis

Oil palm is one of the most important oil crops in the world. Because of its high productivity and perennial nature, it has been expanding quickly. Commercial plantations consist mostly of the African palm E. guineensis Jacq. However, producers in Latin America are increasingly planting the O × G interspecific hybrid, a cross between African palm (E. guineensis) and the American palm (E. oleifera (Kunth) Cortes). This interspecific hybrid has emerged as a promising solution to diseases such as the bud rot of oil palm because of the apparent partial resistance of this genotype to the disease. This work studied and described the phenology of the O × G interspecific hybrid. The phenology stages were coded using the BBCH scale. The scale for the phenophases was defined using a three-digit code. Due to the nature of the palm, no descriptions were used for stage two (formation of side shoots/tillering) and stage four (development of harvestable vegetative plant parts or vegetative reproductive organs) because these stages do not apply to oil palm. The scale was constructed using germinating seeds, pre-nursery and nursery plants and five year-old palms. For the description of the stem elongation, different age palms of the same O × G hybrid were used. Observations were performed during an 18-month period. Additionally, the interval for the change from one phenology stage to another was determined both in days and degree-days (DD). The interspecific O × G hybrid required 6408 DD from when the spear leaf unfolds until the bunch was ripened and harvested, and 4427.6 DD from leaf unfolding to anthesis.

Effect of environmental factors and bulb mass on the invasive geophyte Oxalis pes-caprae development

Oxalis pes-caprae is an invasive pseudoannual plant that reproduces exclusively via offspring bulbs in the introduced range. It is most abundant in disturbed, fertile sites such as agricultural fields, but it is also found in undisturbed shrublands and shadier forest habitats. Oxalis infestation depends on long distance bulb dispersal (mainly anthropogenic) and on the ability of bulbs to grow and reproduce successfully. We conducted a greenhouse experiment to test the effects of parent bulb size on Oxalis growth and offspring production as a function of light availability (ambient and shade), planting depth (surface vs. 9 cm deep), and soil volume (full pots and pots with reduced soil volume). Oxalis grew and reproduced prolifically in all treatments. However, plant development and final offspring bulb production were sensitive to environmental conditions. Shading and reduced soil volume reduced maximum plant biomass relative to control and planting depth treatments, which produced either higher number of offspring bulbs (control) or larger offspring bulbs and higher total offspring bulb biomass (planting depth). Parent bulb size and vegetative reproductive organs had little effect on plant growth and offspring production. Our results are consistent with the lower abundance of Oxalis in undisturbed soils and shadier habitats in the field but indicate that even in these marginal habitats Oxalis can reproduce prolifically and contribute to further spread.

Life Histories of Charophytes from Permanent and Temporary Wetlands in Eastern Australia

The results of an experiment on the demography of charophytes in permanent and temporary sites in two wetlands are outlined and the charophytes that germinated and established are described in relation to their life histories. Three life-history patterns are represented. First, Monoecious annual species germinate easily and rapidly after inundation, they grow quickly and initiate sexual reproduction at the expense of vegetative expansion, produce relatively few, large oospores and die in winter. Second, Dioecious annual species are slower to germinate than Monoecious annuals, they grow more slowly, but also initiate sexual reproduction early in life. They usually produce large numbers of small oospores and die in unfavourable seasons. Both winter-growing and summer-growing Dioecious annuals were represented in experiments. Third, Dioecious perennials germinate after a lag time and establishment; vegetative growth and expansion takes place early in spring. Reproduction in Dioecious perennials is stimulated by increasing water temperatures and other environmental cues. Vegetative reproductive organs are produced in autumn and individual shoots can be very long-lived. Life-history parameters such as germination requirements, establishment requirements and timing of vegetative growth and reproduction can be important in determining the distribution patterns in charophytes.

Development of potato minitubers in microgravity.

Stem segments of aseptically grown potato (Solanum tuberosum L. cv. Zarevo) were cultivated for 4 weeks under laboratory conditions and were then grown for 8 d on board the "Mir" orbital space station. Timing was such that minitubers initiated and developed during the 8 d on the "Mir". Under space flight and stationary conditions, spherical minitubers were formed with no statistically significant differences in either the frequency of tuber formation or tuber size. These observations are the first to document the formation of vegetative reproductive organs and of well developed amylogenic storage tissue during the microgravity conditions of orbital space flight. In these minitubers, a majority of the starch was stored in parenchyma, with numerous amyloplasts per cell. In space flight tissue, however, grain size of starch was decreased and lamellae within the amyloplasts was locally enlarged. Furthermore, mitochondria of these tissues were characterized by increased matrix density and well developed cristae.

Morphology and Taxonomic Significance of Dormant Branch Primordia, Dormant Buds, and Vegetative Reproductive Organs in the Suborders Leucodontineae and Neckerineae (Musci, Isobryales)

The manner of branch development and shape of vegetative reproductive organs were examined for 19families, 101 genera, and 227 species in the suborders Leucodontineae and Neck- erineae (Musci). Two types were recognized in the manner of branch development. They are distin- guished from each other by the nature of dormant condition: One with swollen primordia (type A) and the other with buds (type S). Filamentous pseudoparaphyllia always accompanied type A primordia, whilefoliose pseudoparaphyllia were always with type S. The presence ofscale-like leaves overarching buds was a good marker for recognizing the type S with ease. Each family and genus, with few exceptions, proved to be stable in the manner ofbranch development and shape of vegetative reproductive organs. Therefore, the two-character combination can be used as a new clue for the taxonomy of higher categories. Five genera, which are not closely related, have paraphyllia. The presence ofparaphyllia is correlated with the type S of branch development, and has no taxonomic significance. The familial affinities of two genera are considered; Henicodium is a monotypic genus and classified in the Pterobryaceae, and Penzigiella in the Neckeraceae. Several families of the Leucodontineae have long

Rorippa sylvestris: A new troublesome weed in Swedish forest nurseries

Yellow Cress (Rorippa sylvestris (L.) Besser), a weed difficult to control when established, has recently invaded Swedish nurseries. The properties of the species, as well as measures to avoid its further spreading, are described based on an exhaustive dissertation, other literature and own observations. It is most important to apply preventive measures to stop the species from being introduced and to observe the first establishment phases of the species. If it becomes established it is exceedingly important to prevent the spread of vegetative reproductive organs to unaffected areas.

The Balance between Vegetative and Sexual Reproduction of Mimulus Primuloides (Scrophulariaceae) at Different Altitudes in California

(1) Plants of Mimulus primuloides in populations growing at different altitudes in California have end-of-season values of both total biomass and proportion of biomass in vegetative reproductive organs (vegetative reproductive allocation) which show a maximum value in the middle-altitude population (2500 m). (2) It is suggested that intraspecific competition reduces plant size at low altitudes, resulting in lowered vegetative reproductive allocation; but that a reduction in plant density at the middle altitude allows increased plant size, and therefore increased allocation. At the highest altitude (3400 m), plant size is reduced by the severe environment, again lowering this allocation. (3) Results of controlled environment chamber experiments with plants from five sites grown at three different densities supported this explanation. (4) The number of successful inflorescences per plant decreased with increasing altitude in natural populations. A controlled environment chamber experiment with plants from five sites revealed a positive correlation between total weight per plant and flower weight per plant; a high, genetically-determined, flower production at the highest altitude; and no change in the proportion of biomass allocated to inflorescences with changes in total plant biomass. (5) Although seeds were produced to some extent at all altitudes, seedling establishment was rare. A comparison of vegetative and sexual reproductive allocation in terms of propagules produced showed that the least emphasis on sexual reproduction was at the highest-altitude site. A similar comparison in terms of biomass allocation showed higher allocation to vegetative than to sexual reproduction at all altitudes, but the difference was least at the highest altitude. This increased allocation to sexual reproduction at the highest altitude may be an adaptation for greater potential dispersal or seedling establishment.