Plants In General Research Articles

Variation of Elemental Composition of Leaves in Nitraria schoberi L. and N. sibirica Pall. Depending on Edaphic Growth Conditions

A study was conducted about the variation of levels of macro- and microelements in the soil and leaves of two species of the genus Nitraria L. in various habitats in Siberia. New data were obtained on the concentration variations of K, Na, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Li, Sr, and Cd in leaves of N. schoberi L. and N. sibirica Pall. It was found that the salinity of habitats of N. sibirica (up to 3.23%) can exceed salinity of soils under N. schoberi (up to 0.5%) by more than sixfold. Soils of N. schoberi habitats are characterized by lower contents of carbonates (1.0–3.8%) and of physical clay (2–19%) as compared to soils of N. sibirica habitats: 1.2–18.2 and 9–40%, respectively. An increase in the physical-clay content of soil positively correlated with the accumulation of Mg, Cu (p ≤ 0.01), and Mn (p ≤ 0.001) in the plant leaves. The degree of soil salinity was positively associated with the accumulation of Ca, Zn, Sr (p ≤ 0.01), Mg (p ≤ 0.05), and Cd (p ≤ 0.001) in the leaves. An increase in concentration of mobile Na in soil positively correlated with concentrations of Ca, Cu (p ≤ 0.01), and Zn (p ≤ 0.001) in the leaves. In N. sibirica leaves, the concentration of K, Ca, Mg, Fe, Sr, Mn, Zn, and Cu was 1.5–3 times higher than that in N. schoberi leaves. Both species are capable of accumulating very high concentrations of Na (N. schoberi: up to 83.8 g/kg and N. sibirica: up to 77.2 g/kg). In the leaves of N. schoberi plants of immature age, K and Na levels were seven times higher than those in leaves of adult generative plants, whereas Mg and Ca levels were 3–5 times higher. This study should expand the understanding of mechanisms of Nitraria species’ adaptation to high-salinity conditions.

AGE STRUCTURE OF RHAPONTICUM SERRATULOIDES (GEORGI) BOBR. POPULATIONS. IN NORTHERN AND CENTRAL KAZAKHSTAN

The article presents the results of studying the ontogenetic structure of seven cenopopulations of Rhaponticum serratuloides in Karaganda and Akmola regions of Kazakhstan (Northern and Central Kazakhstan). The majority of surveyed cenopopulations belong to normal incomplete populations. Their ontogenetic structure has two main types of spectrum - centered two-vertex spectrum, where the maximum falls on virginal and middle-generative individuals, as well as left-sided spectrum with predominance of pre-generative individuals. The condition of cenopopulations was assessed using the "delta-omega" criterion of L. A. Zhivotovsky. According to this criterion, most of the cenopopulations are mature (CP 1-2, CP 4-5), only two (CP6 and CP7) are young. The presence of a significant number of young plants in CP6 indicates its high capacity for maintenance and self-restoration. In CP7, unfavorable conditions prevailed and potentially generative plants remained in virginile age state. CP3 occupies an intermediate position between mature and young populations. In all cenopopulations there was almost complete absence of senile and sub-senile individuals, and only in some of them - deposition of juvenile and immature individuals. Incompleteness of cenopopulations is associated with increasing anthropogenic load and narrow ecological amplitude of Rh. serratuloides.

Study of Ontogenetic Structure and Density of the Coenopopulation of Hedysarum atropatanum Bunge ex Boiss. Flora of Daridag

The article presents findings from a study of the demographic structure and density of the population of the species Hedysarum atropatanum Bunge ex Boiss., which is widely distributed in the Daridag area. A total of ten ontogenetic states (seed, seedling, juvenile, immature, virginile, young generative, middle aged generative, aged generative, subsenile and senile) of the H. atropatanum species were observed. The processes of ontogenesis, which can be classified as normal, fast, or slow, were identified as the primary mechanisms driving species evolution. Additionally, instances of developmental disruptions, rejuvenation, and the manifestations of aging were observed. The majority of individuals belonging to the species H. atropatanum exhibit a normal to rapid growth rate. It has been observed that the process of ontogenesis is slower in areas with high plant density. It was determined that the secondary quiescence period does not manifest during the initial stages of development; rather, it becomes feasible only after the individuals have reached the virginal state. It has not been observed that immature individuals bypass the virginal state and immediately transition to mature generative plants. The vitality status of the individuals was determined based on a comprehensive analysis of multiple morphological traits, including the height of the specimens, the number of shoots, the number of flower carriers, the length of the leaves, the size of the leaves, and the number of flowers in the flower group. Following the statistical processing of the data, three classes of vitality were identified. A study revealed that individuals of the second vitality level of the H. atropatanumspecies are more prevalent in the coenopopulation. The optimal habitats of the H. atropatanum s

Study of the Floristic, Morphological, and Genetic (atpF-atpH, Internal Transcribed Spacer (ITS), matK, psbK-psbI, rbcL, and trnH-psbA) Differences in Crataegus ambigua Populations in Mangistau (Kazakhstan).

This article studies the morphological parameters of vegetative and generative organs of different age groups of Crataegus ambigua from four populations in Western Karatau (Mangistau region, Kazakhstan). In this study, we examined four populations: Sultan Epe, Karakozaiym, Emdikorgan, and Samal, all located in various gorges of Western Karatau. Several phylogenetic inference methods were applied, using six genetic markers to reconstruct the evolutionary relationships between these populations: atpF-atpH, internal transcribed spacer (ITS), matK, psbK-psbI, rbcL, and trnH-psbA. We also used a statistical analysis of plants' vegetative and generative organs for three age groups (virgin, young, and adult generative). According to the age structure, Samal has a high concentration of young generative plants (42.3%) and adult generative plants (30.9%). Morphological analysis showed the significance of the parameters of the generative organs and separated the Samal population into a separate group according to the primary principal component analysis (PCoA) coordinates. The results of the floristic analysis showed that the Samal populations have a high concentration of species diversity. Comparative dendrograms using UPGMA (unweighted pair group method with arithmetic mean) showed that information gleaned from genetic markers and the psbK-psbI region can be used to determine the difference between the fourth Samal population and the other three.

Structure of cenopopulations of <i>Heracleum sosnowskyi</i> and mechanisms for maintaining their stability in north conditions

The growth and productivity, rhythm of development, ontogenetic and spatial structure of cenopopulations of Sosnowsky's hogweed (Heracleum sosnowskyi Manden.) on the territory of the Komi Republic were studied. The duration of the growing season of H. sosnowskyi was 180–190 days due to the early spring germination of seeds and the long autumn growing season of pregenerative individual plants. The studied H. sosnowskyi CPs were characterized by left-sided ontogenetic spectra and high recovery indices. These properties characterized them as young and self-renewing plants. The greatest and the lowest numbers per the unit area had the juvenile and the generative plants (710–1700 and 1–3 individuals/m2, respectively). The average density of immature and virginile individuals was 4–7 pcs/m2 and 12–16 pcs/m2, respectively. The absence of seedlings during the flowering period of plants was discovered, resulting from of the synchronous germination of mericarps and the rapid passage of the post-emergence development stage. Plants began to flower at the age of 2–6 full years, the maximum lifespan of individuals was 7 years. H. sosnowskyi plants were characterized by high productivity. They formed up to 15 kg/m2 of wet phytomass, half of which was produced by generative individuals. The main part of the leaf area of the generative individuals was located in the upper layers (like an “inverted pyramid”) and absorbed about 70% of the incoming PAR. The identified mechanisms of the CP self-maintenance mediate the spread and retention of occupied territories which are occupied by H. sosnowskyi plants on the northern border of the invaded range.

Growth response of sweet kaffir lime (Citrus hystrix) seeds due to kinetin and coconut water application using tissue culture technique

Sweet kaffir lime is one of Aceh’s local fruit crops, which is rarely found anymore. The problem of sweet kaffir lime cultivation is the difficulty of generative and vegetative plant propagation. The general objective of this research is to preserve the Acehnese sweet kaffir lime from extinction. One way that can be done is through plant propagation in tissue culture. The experiment was conducted in the Plant Tissue Culture laboratory of the Faculty of Agriculture, Universitas Malikussaleh. This research used a two-factor, completely randomized design, and ten replications. Two factors were tried: the concentration of kinetin (0, 1, and 2 mg/L) and the concentration of young coconut water (0, 15, 30 %). The results showed that increasing kinetin concentration could reduce shoot length, number of leaves, root length and slow the root emergence time of sweet kaffir lime in vitro. The best treatment was the 0 mg/L kinetin (without kinetin). Increasing coconut water concentration could increase shoot length, number of leaves, and root length of sweet kaffir lime in vitro. The best treatment was 30% coconut water concentration.

Image-based classification of wheat spikes by glume pubescence using convolutional neural networks.

Pubescence is an important phenotypic trait observed in both vegetative and generative plant organs. Pubescent plants demonstrate increased resistance to various environmental stresses such as drought, low temperatures, and pests. It serves as a significant morphological marker and aids in selecting stress-resistant cultivars, particularly in wheat. In wheat, pubescence is visible on leaves, leaf sheath, glumes and nodes. Regarding glumes, the presence of pubescence plays a pivotal role in its classification. It supplements other spike characteristics, aiding in distinguishing between different varieties within the wheat species. The determination of pubescence typically involves visual analysis by an expert. However, methods without the use of binocular loupe tend to be subjective, while employing additional equipment is labor-intensive. This paper proposes an integrated approach to determine glume pubescence presence in spike images captured under laboratory conditions using a digital camera and convolutional neural networks. Initially, image segmentation is conducted to extract the contour of the spike body, followed by cropping of the spike images to an equal size. These images are then classified based on glume pubescence (pubescent/glabrous) using various convolutional neural network architectures (Resnet-18, EfficientNet-B0, and EfficientNet-B1). The networks were trained and tested on a dataset comprising 9,719 spike images. For segmentation, the U-Net model with EfficientNet-B1 encoder was chosen, achieving the segmentation accuracy IoU = 0.947 for the spike body and 0.777 for awns. The classification model for glume pubescence with the highest performance utilized the EfficientNet-B1 architecture. On the test sample, the model exhibited prediction accuracy parameters of F1 = 0.85 and AUC = 0.96, while on the holdout sample it showed F1 = 0.84 and AUC = 0.89. Additionally, the study investigated the relationship between image scale, artificial distortions, and model prediction performance, revealing that higher magnification and smaller distortions yielded a more accurate prediction of glume pubescence.

MORPHOSTRUCTURE OF MOEHRINGIA HYPANICA GRYNJ & KLOKOV IN THE NATIONAL NATURE PARK «BUZKY GARD»

The ecological, edaphic and morphological features and population status of the endemic species Moehringia hypanica Grynj & Klokov were studied within the steppe zone of Ukraine. For the first time, soil analysis, which was taken directly from the places of growth of individuals of the studied species, was carried out. The highest soil content was found in niches under stones (25%), and the lowest in microcracks of granite rocks (5%) of the total volume. The levels of soil supply with mobile nutrients and humus were analysed. The analysis of the cationic and anionic composition of the water extract of the soil showed that M. hypanica belongs to the non-saline soils (the amount of salts does not exceed 0.1%). The content of all salts does not exceed the toxicity thresholds. The results of the soil analysis showed that in order to preserve the populations of these endemic plants, it is necessary to maintain a stable chemical composition of the substrate and prevent human interference. For the first time, it was found that during flowering and fruiting, M. hypanica lacks moisture in the air and substrate. The ability of the plants to grow and develop fruit formation under drought and heat conditions indicates their drought tolerance and thermophilicity. During the expeditionary research, we noted that the populations are dominated by young generative and medium generative plants, with a small number of old generative and virgin individuals. The presence of these aged individuals indicates sufficient seed reproduction. The morphological characteristics of seeds, fruits and age states of M. hypanica plants were determined for the first time.

To the biology of Ligularia sibirica in the South Ural Reserve

The article presents the results of studying the life and reproductive characteristics of plants of the relict for Europe Eurasian polymorphic species Ligularia sibirica (L.) Cass. in three coenopopulations in the conditions of the South Ural Nature Reserve. The plant is little studied in the Ural region, medicinal and very effective, therefore in many ways promising for study in introduction purposes. In natural coenopopulations it grows in fairly moist areas, occurs sparsely in meadows, and in dense clusters under the forest canopy. In forest cenoses, Ligularia sibirica plants are tall and look much larger than in meadow cenoses. In different ecotopes, the variability of morphometric characters is not the same and is specific to a particular habitat. The characteristics of the generative sphere vary to a greater extent relative to the vegetative one. Analysis of variance revealed the dependence of the height of the generative shoot on the plant habitat (56.8%), as well as the length and width of the stem leaves on the ecotope conditions (51.3-69.2%). The age structure of the CP has a right-sided single-vertex type of spectrum with a predominance of young generative plants and a low proportion of mature ones. The superiority of generative plants in the spectra is due to the seed renewal of this species. Ligularia sibirica is distinguished by high reproductive rates with a fairly high coefficient of seed productivity (91%). However, the germination rate of its seeds is quite low, since the seeds are characterized by shallow organic dormancy, from which the seeds can be removed by short stratification or by storing the seeds in dry conditions. In the Southern Urals, this species requires further study.

Population study of Allium altaicum Pall. in Kazakhstan Altai

The purpose of this work was population studies of Allium altaicum Pall. on the territory of the Kazakhstan Altai in 3 territorially isolated geographical regions: Southern, South-Western Kalba Altai. As a result of the survey of the territory by the route-reconnaissance method on the ridges of Sarymsacty, Lineysky and Kalba, a study was made of populations that are characterized by different environmental conditions and altitudinal limits. Ecological and phytocenotic screening revealed that on the Sarymsactyridge the population is located in the alpine belt in the altitudinal limit of 1870 m a.s.l., on the Lineyskyridge ‒ in the mountain-forest, 1361 m.a.s.l.Both populations are characterized by meso-psychro-petrophytic growing conditions. On the ridge ridgeKalba, the population was examined in the mountain-steppe xero-meso-petrophytic conditions, 832 m a.s.l. Soils are mountain chernozems, slightly acidic, pH 5.6–5.9, with a high humus content from 13.5% to 14.9%, the ground cover is formed, 210–410 g/m2.In all populations, the vegetation cover is based on herbaceous perennials; layering is not pronounced. Participation of A. altaicum in the formation of phytocenosis on the ridge Sarymsacty is 3.2%, Lineysky ‒ 2.2%; Kalba ‒ 1.8%. The florocomplex of the surveyed populations is formed from 91 species of vascular plants.The similarity of the floristic compositions of the Sarymsacty population in alpine meso-psychro-petrophytic conditions and Lineysky in mountain-forest meso-psychro-petrophytic conditions at the level of 65.0% in relation to the entire cenoflora was established, and Kalba in mountain-steppe xero-meso-petrophytic conditions this figure was 42.1%. Variability of morphometric parameters of aboveground organs of A. altaicum in all examined populations has an average and high level of variability from 15.0 to 26.09%, which indicates the ecological plasticity of plants. It has been established that in nature vegetative reproduction occurs only in virginal and generative plants, and nests are formed. The biomorphological parameters of the bulbs in the nest have a clearly expressed age character and vary within the same coenopopulation.

GYNODIOECY IN <i>GERANIUM PSEUDOSIBIRICUM</i> (GERANIACEAE)

A breeding system of the gynodioecious Geranium pseudosibiricum J. Mayer in three meadow and meadow-steppe communities of the Altai Mountains was investigated. Statistically significant differences in the morphology of flowers between hermaphrodite and female plants have been established (p 0.001). The stamens of pistillate flowers in females are reduced and do not produce pollen. Statistically significant differences between the sexes in seed productivity have been established: female plants form several times more fruits than hermaphrodite ones (p 0.01); a high female compensation was detected for G. pseudosibiricum. Infertile hermaphrodite plants were found in the coenopopulations. Female palnts in the coenopopulation CP1 constitute 55% of the total number of generative plants. In natural habitats, G. pseudosibiricum is characterized by good seed breeding and successful formation of offspring, which contributes to the maintenance of female plants in the coenopopulations of the species. The features of breeding system of G. pseudosibiricum have revealed significant differences between female and hermaphrodite plants.

The current state of the cenopopulations of Adonis tianschanica (Adolf) Lipsch. (Ranunculaceae) in Southeast Kazakhstan

Abstract. Kulymbet K, Mukhitdinov N, Kubentayev S, Tynybayeva K, Tastanbekova A, Kurmanbayeva M, Gafforov Y, Kaparbay R, Zhumagul M. 2023. The current state of the cenopopulations of Adonis tianschanica (Adolf) Lipsch. (Ranunculaceae) in Southeast Kazakhstan. Biodiversitas 24: 4359-4372. Adonis tianschanica (Adolf) Lipsch. is a rare, sub-endemic species growing in the Tien Shan mountains with declining numbers, making it listed in the Red Book of Kazakhstan. The aim of the study is to investigate the distribution and abundance of A. tianschanica cenopopopulations (CP) in its natural habitats in southeastern Kazakhstan as well as assess soil characteristics, biological and arealogical features, including the ontogenetic structure of cenopopopulations. Five cenopopulations (CP) of A. tianschanica were identified, namely two CPs in Ketmen Ridge (Kegen Pass), two CPs in Dzungarian Alatau (Tekeli Gorge) and one CP in Terskey Alatau (Saryzhaz). Vegetation data were collected using the traditional methods of field geobotanical studies based on the ecological-physiognomic approach.Plant communities having dominant species from a single ecobiomorph and ecologically related species groups.We complemented the population analysis with a soil properties map compiled from existing cartographic and available literature. The results of this study indicated the low number of A. tianschanica individuals in all CPs, which is likely due to the biological characteristics of the species (i.e. low seed production and seedling recruitment and the lack of vegetative regeneration) as well as environmental factors, and anthropogenic impact, mainly grazing with. We found that the total number of individuals of A. tianschanica in the five cenopopulations was 106 individuals. The average density of the species varied from 1.3 to 3.1 plants/m2 with CP2 being the highest and CP5 the lowest. The five cenopopulations were classified based on the absolute maxima of ontogenetic groups. There were two maxima in the age composition of individuals in CPs 3 and 4: the first (18.8-42.1%) was a group of vegetative plants (v), and the second (21.1-50.0%) was a group of young generative plants (g1). The natural state of the habitat of this cenopopulation can be explained as more favorable than others. In CP2, the absolute maximum corresponded to vegetative plants group (v) (37.0%). In CP5, young generative individuals (g1) and mature generative (g2) predominated (from 30.8% to 38.4%). In terms of age composition, the state of A. tianschanica cenopopulations is considered relatively satisfactory but demonstrated a low level of abundance. It has been established that the state of the species populations in the studied regions is affected by soil conditions, changes in climatic conditions and anthropogenic impact.

Response of Growth and Yield of Mint (Mentha spicata L.) Cuttings to Auxin and Composition of Planting Media

Consumption of herbal medicines by Indonesian people is increasing because of the price and ease of obtaining them. One of the main ingredients of herbal medicine is mint leaves because they contain tannin and flavonoid secondary metabolites. However, the generative mint plant is very slow and needs vegetative cuttings propagation. This study aims to examine the effect of auxin-type growth regulators and the composition of the growing media on the growth and yield of mint plant cuttings. This study used a complete randomized block design with two factors. The first factor was the auxin growth regulator with four levels: without growth regulator, IBA 500 ppm, IAA 500 ppm, NAA 500 ppm. The second factor was the composition of the planting medium with three levels, namely soil, husk charcoal, and goat manure 3:3:1; 3:2:2, and 3:1:3. Three repetitions were carried out. Auxin affects the number and area of leaves. Applying 500 ppm NAA encouraged the highest leaf growth, with the number of leaves at 163.38. Growth regulator NAA 500 ppm increased the number of leaves and leaf area of mint plants, i.e., by 0.01% and 1.16% compared to the control. The growing media composition affected the crown fresh weight, root biomass, and crown root ratio. The media composition of 3:3:1 produced a crown fresh weight of 41.07 g, and the media composition 3:3:3 produced the highest biomass of 5.97 g. The media composition 3:1:3 showed the highest root crown ratio, 2.69%. Auxin and the composition of the growing media synergistically promote the growth and yield of mint cuttings.

Structural and functional characteristics of the assimilation apparatus of <i>Alisma plantago-aquatica</i> at different stages of development

This paper deals with the features of the structural and functional organization of the assimilation apparatus of individuals of the plantain fly, which are in five ontogenetic states (juvenile, immature, virginal, young and middle-aged generative). The changes in the morphometric parameters of the assimilation apparatus in j, im, v, g₁ and g₂ individuals of Alisma plantago-aquatica are analyzed. During the ontogenesis of Alisma plantago-aquatica, the length, width, area and mass of the sheet plastic, as well as the growth coefficient, changed along an S-shaped curve. In the middle-aged generative plants of Alisma plantago-aquatica, all morphometric parameters had maximum values. During the pregenerative (three ontogenetic states) and generative (two ontogenetic states) periods of ontogenesis, the number of chlorophylls a and b, carotenoids in the leaves of the helophyte increased. Regardless of the ontogenetic state of plants, the concentration of yellow pigments was 3,06,0 times lower than of the green ones. The degree of functionality of the photosynthetic apparatus in individuals of different ontogenetic states can be judged both by the ratio of chlorophyll a to chlorophyll b, and the ratio of the sum of chlorophylls to carotenoids. With an increase in the total assimilating surface of the leaves, the intensity of photosynthesis and, as a consequence, the amount of organic carbon in the leaves of Alisma plantago-aquatica individuals increased. The structural and functional changes of the photosynthetic apparatus observed in the ontogenesis of Alisma plantago-aquatica can be explained by the peculiarities of adaptation mechanisms to long-acting external environmental factors. Medium-aged generative plants of Alisma plantago-aquatica are promising for assessing carbon accumulation and overall productivity of coastal-aquatic phytocoenoses.

Portraits of Science Misconceptions in Plant Adaptation and Breeding Materials in Elementary Schools

A misconception is a misunderstanding of a concept by someone. Misconceptions can be experienced in various situations, one of which is in the learning process. This research takes the learning in elementary schools, especially on plant adaptation and reproduction. Misconception itself occurs due to many factors. This study aimed to determine whether there were misconceptions about plant adaptation and reproduction in the elementary schools studied. The researcher used a descriptive qualitative approach. This type of qualitative research uses a descriptive approach. The population in this study amounted to 47 students. Sampling was done using probability sampling. Data collection techniques used were tests and interviews. The test instrument used is to give 15 question numbers to students. The data analysis technique used is descriptive qualitative analysis. The study results showed that 19% of the samples had misconceptions about vegetative propagation of plants, 13% of generative plant propagation, and 2% of plant adaptation material. The teacher also explained that only a few students needed clarification, and the rest needed help understanding the concept. There are many ways to overcome misconceptions, starting from learning media, using worksheets, developing critical thinking in students, and many more. It was concluded that elementary school students have misconceptions.

Thirteen years of monitoring a coenopopulation of <i>Eritrichium caucasicum</i>: Stochastic growth rate under reproductive uncertainty

Eritrichium caucasicum is an alpine short-lived perennial species endemic for the Caucasus. The stage structure of a local population has been observed on permanent plots in the alpine belt of the Northwestern Caucasus annually for 13 years (2009–2021), accumulating data of the “identified individuals from unknown parents” type. The latter circumstance has predetermined what is called reproductive uncertainty in the terminology of matrix models for discrete-structured population dynamics and means that the annual recruitment rates inherent in the groups of generative plants and final flowering generative plants cannot be calibrated in a uniquely way. As a result, instead of the annual values of the asymptotic growth rate, the model gives only certain ranges of their values that vary from year to year, corresponding to the data. This introduces both technical difficulties and uncertainty in the viability forecast based on the asymptotic growth rates. A well-known alternative approach is to estimate the stochastic growth rate λS, but only artificial modes of randomness involved in the calculation of λS have been proposed in the literature. Our realistic model of randomness is related to variations in weather and microclimatic conditions of the habitat. It is reconstructed from a fairly long (60 years) time series of the weather indicator. Using this realistic model in Monte Carlo calculations of λS, we have obtained a more reliable and accurate estimate of the stochastic growth rate.

SEXUAL POLYMORPHISM OF <i>RANUNCULUS CASSUBICUS</i> (RANUNCULACEAE) IN MOSCOW REGION

For the first time, gynodioecy is described in a perennial herbaceous polycarpic plant Ranunculus cassubicus L. (Kashubian buttercup) in the Moscow Region. It was revealed that R. cassubicus forms three types of flowers differing in the androecium structure: perfect (with fertile stamens and carpels), partially male-sterile (the number of stamens varies greatly and is much less than in perfect flowers), and pistillate ones (stamens completely missing). The sizes of flowers and their parts decrease in many studied parameters in the following row: perfect – partially male-sterile – pistillate. The studied 12 populations included six types of individuals forming: 1) only perfect flowers (83.1–89.2% of the total number of generative plants); 2) perfect and partially male-sterile flowers (4.0–6.5%); 3) only partially male-sterile flowers (2.8–3.9%); 4) perfect and pistillate flowers (1.4–2.6%); 5) pistillate and partially male-sterile flowers (1.2–2.9%); 6) only pistillate flowers (0.6–1.5%). It is established that over three years of observations (2020–2022), individuals of different sexual forms did not change the sex of flowers, and the sexual structure of populations remained stable, without sharp fluctuations.

Reproductive Success of <i>Dactylorhiza fuchsii</i> (Druce) Soó at the Northern Border of Its Distribution Range

The paper presents data on the population structure, morphometric features of plants and seeds and some aspects of reproductive biology (fruit set, seed productivity) of Dactylorhiza fuchsii (Druce) Soó (Orchidaceae) on the northern border of its distribution area (the Komi Republic, northeast Russia). We found statistically significant decrease of seed size and flowers number per inflorescence from south to north within of the species distribution area. In the Komi Republic, the seed productivity of Dactylorhiza fuchsii was found to be lower than in the southern parts of its distribution area: one fruit contains an average of 2900 ± 80 seeds, the average real seed productivity of the generative plant is 24800 seeds. Despite the declination of some reproductive success indicators, in the northern territories the species forms quite large, well-regenerating populations.

Mathematical model for soybean mosaic disease transmission with entomopathogen interventions and photoperiodicity

Mosaic is a severe disease of soybeans that has the potential to reduce the quality and quantity of soybean production. The Mosaic disease can infect soybean plants by the Aphis vector carrying Soybean Mosaic Virus (SMV). In this study, a mathematical model of the spread of Mosaic disease was built by considering two interventions, namely the application of entomopathogen and the regulation of photosynthesis intensity. This research focuses on knowing the effect of intervention in controlling Mosaic disease and increasing the population of susceptible generative plants. Using dynamical system theory, non-endemic and endemic equilibrium points and their stability are obtained. Then, the basic reproduction ratio (R0) is obtained for this model. Sensitivity analysis was carried out to determine the most influential parameters in the model. Optimal control theory was used to determine the optimal conditions of the model by considering the cost of entomopathogen application and photoperiodicity. The results of numerical simulations show that the application of entomopathogen and photosynthetic intensity can suppress the population of plant and vector infections and increase the population of susceptible plants in the generative phase at the same time.

The Impact of Hydrilla Compost on Puspa (Schima wallichii (D.C.) Korth.) Seedling Growth

The Puspa tree (Schima wallichii (D.C.) Korth.) is often used in reforestation and forest restoration activities. Puspa seed propagation techniques can be applied by generative or vegetative plant propagation. The lack of nutrients causes the availability of Puspa seeds very limited. Organic nutrients are used to obtain quality fertile plants and to accelerate growth. In this study, organic nutrients from Hydrilla plants. This study aimed to determine the best application of Hydrilla compost on the growth of Puspa seedlings. The research method used is quantitative. This study used a randomized block design (RBD) with levels of 3 treatments and nine groups, so there were 27, 3 samples were taken for each group, so there were 81 tillers. The treatments in this study were H0 (2000 grams of topsoil), H1 (2000 grams of topsoil and 200 grams of hydrilla compost), and H2 (2000 grams of topsoil and 400 grams of hydrilla compost). The method of work in this research was making hydrilla compost, preparing puspa seeds, planting puspa seeds, and caring for puspa seeds. The observed variables were growth rate (%), number of leaves (strands), plant height (cm), stem diameter (mm), and growing root length (cm). The results showed that the H2 treatment gave the best results for plant heights that were very significantly different, with an average of 8.45 cm, the number of leaves was very significantly different, with an average of 11 strands and root lengths of 4.13 mm.