Leaf Growth Research Articles

Classroom data science: data and dataing for making sense of multivariate plant growth

Abstract What is considered data and how it is communicated publicly is rapidly changing. Participation in society involves multiple opportunities to engage with complex statistical concepts in media, in personal health, and regarding climate change. Children also are engaging with evolving data types in social media interactions and in educational contexts where they are the data. Yet little time is spent in classrooms supporting children to explore and make their own data decisions about various data types. This study investigates the role that fourth graders’ use of graphing conventions played in supporting their conceptual development of: non-traditional data and dataing during one lesson. The author hopes to contribute a new perspective in conceptualising dataing as enculturating statistical practices around data that involves multiple features, to communicate key information, involving tools for engaging with statistics to communicate a story. In this case study, a video clip presented an entrance point in exploring multivariate data (multiple variables). Video observation and student graphs revealed insights into children’s data and dataing experiences and processes involved with multivariate data, supported by a classroom culture that valued statistical processes as a creative and meaningful, story-telling endeavour. When students were tasked with representing plant growth using a graph, displays included a wide range of variables such as patterns of leaf growth and qualitative stages of plant growth. Engaging with multivariate data in exploratory ways supported students in this study to play with graphing conventions, establishing local mathematical practices involving non-traditional data.

Changes in the potato rhizosphere microbiota richness and diversity occur in a growth stage-dependent manner

Plant root and soil-associated microbiomes are influenced by niches, including bulk and rhizosphere soil. In this work, we collected bulk and rhizosphere soil samples at four potato developmental stages (leaf growth, flowering, tuber elongation and harvest) to identify whether rhizosphere microbiota are structured in a growth stage-dependent manner. The bacterial and fungal microbiota showed significant temporal differences in the rhizosphere and bulk soil. Rhizobacteria were most diverse at the tuber elongation stage, and dominant ASVs identified as Sphingomonas, Rhodanobacter, Sphingobium, Hyphomicrobium, and Solirubrobacter spp. In contrast, rhizosphere fungal diversity peaked at flowering stage, with Lecanicillium spp. being prominent. Furthermore, the abundance of saprophytic fungal genera, including Colletotrichum and Fusarium, and Alternaria, sharply increased at harvest stage, likely contributing to plant residue decomposition. Indicator taxa analysis highlighted the dominance of these genera at harvest. Network analysis revealed increased microbial complexity during the later growth stage, with 721 edges compared to 521 edges in the early growth stage. This increase included positive correlations between bacteria and negative correlations between bacteria and fungi. These changes suggest that microbial interactions become more interconnected and complex as potato plants mature. Our findings highlight the potential role of saprophytic fungi in shaping microbial dynamics during the later growth stage in rhizosphere soil.

Establishment of a Breeding Approach Combined with Gamma Ray Irradiation and Tissue Regeneration for Highbush Blueberry

Blueberries are a relatively recently domesticated species, primarily bred through hybridization. Mutation breeding, which uses chemical or physical treatment to increase plant mutation, has not yet been applied to blueberries. This study introduces a mutation breeding strategy for the highbush blueberry cultivar Vaccinium corymbosum. We established a high-efficiency regeneration protocol, which was applied to leaves and stems exposed to gamma irradiation using 60Co-γ rays at doses of 10, 20, 40, 80, and 120 gray (Gy), to increase the efficiency of mutated cells to develop into adventitious shoots. We determined that the median lethal dose (LD50) was approximately 56 Gy for leaf explants and 80 Gy for stem explants. Phenotypic variations, including changes in leaf color and growth characteristics, which may be due to altered plant response to environmental factors, were successfully observed in the first-generation (M1) plants. The height of M1 plants quantitatively decreased with increasing irradiation doses. To evaluate the mutants induced by each irradiation dose, whole-genome resequencing was conducted on individuals from each dose group, revealing significant genomic alterations at the 80 Gy dose. This approach provides a valuable reference for future blueberry breeding programs aimed at enhancing genetic diversity and improving cultivar performance.

Combined Impacts of Climate and Tree Physiology on Mercury Accumulation in Tropical and Subtropical Foliage and Robust Model Parametrization.

Atmospheric elemental mercury (Hg0) assimilation by foliage contributes prevalently to the global atmospheric Hg0 sink in forests. Today, little is known about the mechanisms of foliar Hg accumulation and how climate factors and tree physiology interact to impact it. Here, we examined meteorological factors, foliar physiological traits, and Hg accumulation rates from leaf emergence to senescence in a tropical rainforest, tropical savanna, and subtropical evergreen broadleaf forest. Also, robust models for foliar Hg accumulation were parametrized. Generally, foliar Hg accumulation rate in subtropical evergreen forest was highest (16.4 ± 12.3 ng m-2 day-1), followed by the tropical rainforest (14.2 ± 9.8 ng m-2 day-1), and lowest in the tropical savanna (4.7 ± 4.9 ng m-2 day-1). Atmospheric relative humidity, stomatal conductance, and leaf photosynthesis are key drivers of spatial-temporal variations in foliar Hg accumulation. The canopy-structure-induced specific leaf physiological traits drive temporal variations in foliar Hg accumulation, and climate-controlled leaf physiological traits account for spatial variations among three forests. Finally, our robust models enable precise simulation of foliar Hg accumulation rates at both tree species and ecosystem scales facilitating particularly regional and global Hg transport and chemical models to quantify the vegetation's role as a sink for atmospheric Hg0 uptake.

Standardization of size of cutting and IBA concentrations on the multiplication of underutilized leafy vegetables of Assam

An experiment unfolded at the Experimental Farm in the Department of Horticulture, AAU, Jorhat during 2021-22 to analyse the effect of different concentrations of IBA viz., H1: distilled water, H2: 25 ppm, H3: 50 ppm and H4: 75 ppm on three different cutting sizes (N1: 1 node, N2: 3 nodes, N3: 5 nodes) across three underutilized leafy vegetables (Brahmi, Matikanduri, Madhusoleng). In nursery, the experiment (I) was put out in Factorial Randomised Block Design (FRBD) from which the best and the poorest treatment of each crop were planted in the main field for further studies on their growth. In the main field, the experiment (II) was laid out in Randomized Block Design with four replications. The interaction between cutting size and IBA concentration spotlighted N3H4 as the pinnacle treatment in Brahmi displaying superior rooting percentage, longest root length, root diameter, highest root fresh and dry weights, highest root number, and hastening new leaf appearance. In Matikanduri, N3H4 excelled in rooting percentage, root length, root diameter, fresh weight, and root number, whereas N3H3 caused the maximum root dry weight and quickest new leaf emergence. Madhusoleng exhibited optimal results with N3H4, showcasing the highest rooting percentage, longest root length, root diameter, root fresh and dry weights, root number, and minimum time to new leaf appearance. In the main field, Brahmi-survival percentage (99.50%), plant height (21 cm), plant spread (29.25 cm), number of branches (3.75), leaf number (21.25), Matikanduri- survival percentage (98.75%), plant height (40.45 cm), plant spread (68.95 cm), number of branches (38.25), leaf number (330.50), Madhusoleng- survival percentage (98.50%), plant height (82.00 cm), plant spread (102.25 cm), number of branches (31.00), leaf number (378.75) were found to be best in the same treatment combination of N3H4 with maximum BC ratio of 3.31, 4.46, and 5.80, respectively.

Changes in key volatile components associated with leaf quality of Pandanus amaryllifolius Roxb. alongside growth duration.

Pandan (Pandanus amaryllifolius Roxb.) are one of the traditional food materials in Southeast Asian countries. However, there has long been a lack of understanding of the differences in volatile organic compounds (VOCs) of leaves at different growth periods. Gas chromatography-mass spectrometry (GC-MS) was used to identify and analyze VOCs in different leaf positions of Pandan in this study. The content of 2-Acetyl-1-pyrroline (2AP) was higher in L1-L3 and decreased with leaf growth, while squalene showed the opposite trend. The content of neophytadiene first increased and then decreased, reaching the highest in L15. L8 is the critical point at which the content of each major VOCs is balanced. Combining agronomic traits and VOCs content, leaves in L4-L25 position are suitable for harvesting. This study provides data support for scientific judgment of the harvesting site and time of Pandan, and provides theoretical basis for further utilization of VOCs of Pandan.

Altering growth and antioxidant responses of basil cultivars with aluminum oxide nanoparticles in vitro

The rapid advancement of nanotechnology has resulted in a significant increase in the production of metal oxide nanoparticles, which are increasingly released into the environment. Due to their widespread distribution, evaluating the potential toxicity of these particles is essential. Aluminum oxide nanoparticles (Al2O3 NPs), in particular, are widely used in various industries and consumer products. Basil, a valuable medicinal herb known for its essential oils and antioxidants, has numerous health benefits. The impact of Al2O3 NPs on plants remains largely unexplored. This study investigated the effect of different concentrations of Al2O3 NPs and their bulk form (AlCl3; BP) on the growth of red Rubin and sweet basil cultivars in vitro, focusing on the induction of non-enzymatic and enzymatic antioxidant responses. Growth parameters were adversely affected by variations in cultivar, Al particle size, and concentration. The highest reductions occurred at 200 mg L−1 NPs or BPs, with decreases of up to 69.34% for red Rubin and 63.33% for sweet basil. Al NPs and BPs reduced chlorophyll a, b, and carotenoid levels. These pigments showed the highest decreases at 200 mg L−1, with reductions of up to 81.92% for red Rubin and 75.96% for sweet basil. Al NPs and BPs compromised membrane integrity, inducing oxidative stress, as evidenced by increased electrolyte leakage, UV-absorbing compounds, malondialdehyde (MDA), and hydrogen peroxide (H2O2) levels. The phenolic and amino acid concentrations in red Rubin basil leaves and roots decreased in response to increasing NP concentrations, while the opposite trend was observed for BPs. Conversely, sweet basil showed a consistent upward trend in phenolic and amino acid levels as Al concentrations increased, irrespective of particle form. The content of soluble proteins in basil leaves and roots declined as the concentrations of NPs and BPs increased. Enzyme activities, including superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), phenylalanine ammonia-lyase (PAL), and polyphenol oxidase (PPO), increased in basil leaves and roots when exposed to rising concentrations of NPs and BPs. Catalase (CAT) activity increased in red Rubin leaves and roots but decreased in sweet basil leaves and roots, with rising concentrations of NPs and BPs. The observed variations in leaf and root growth between the two basil cultivars exposed to different concentrations of Al NPs and BPs suggest that cultivar physiology and particle characteristics play a role. Additional studies are required to clarify these mechanisms.

Effects of two amino acid transporter-like genes on potato growth.

Amino acid transporters are membrane proteins that mediate amino acid transport across the plasma membrane. They play a significant role in plant growth and development. The amino acid permease (AAP) subfamily belongs to the activating transcription factor family, which is one of the main amino acid transporter families. Potato AAP genes were identified through simple bioinformatics, and the functions of StAAP1 and StAAP8 were verified by plant subcellular localization and potato transgenic technology. In this study, eight AAP-like genes in potato were separated into two subgroups based on the differences in the number of pore-lining residues. To identify the locations where the genes were expressed, we built green fluorescent protein expression vectors for two genes, StAAP1 and StAAP8, and found that these two genes were expressed on the plasma membrane. Meanwhile, we constructed overexpression vectors for these two genes to construct transgenic plants. By observing the phenotype of the transgenic plants, we concluded that StAAP1 and StAAP8 promoted leaf growth and increased leaf area and StAAP1 elongated the potato tubers. Overall, these two genes did not significantly affect tuber weight or number. However, the assessment of amino acid content in potato tubers showed that StAAP8 overexpression increased the content of amino acids, and some of these amino acids were related to protein synthesis. Therefore, StAAP8 overexpression may promote the accumulation of plant amino acids. Studies have shown that there are some differences in the functions of different transcription factor members. The studied AAP8 gene plays a role in amino acid transport and protein accumulation in potato tubers, which provides support for subsequent research on potato tuber nutrition.

Physio- Biochemical and Molecular Changes Associated with Waterlogging Stress in Sugarcane: A Review

The term waterlogging refers to a condition of short/ long term water stagnation due to reduced capacity of the drainage system. In India, physical degradation of soil due to waterlogging has been estimated to be 8.5 million ha. It usually occurs due to rise in water table in almost all the canal irrigated areas with poor drainage system. Effects of waterlogging are augmented by secondary salinization and it aggravated the incidence of certain pests and diseases. In sugarcane, waterlogging is one of the major abiotic stresses affecting cane and sugar productivity. In many parts of the India, like eastern UP, northern Bihar and deltaic region of Tamil Nadu, sugarcane suffers from waterlogging during elongation phase because of heavy monsoon rains and poor drainage facilities. Higher water table during grand growth phase adversely affects cane weight and shoot population which occurs due to shift in respiratory metabolism from aerobic to anaerobic condition. Waterlogging not only reduced root growth, leaf emergence rate but also caused destruction of root function, hormone balance and nutrient availability. Sugarcane crop affected with waterlogging stress showed aerial rooting, cane lodging and decreased cane and sugar yield. Under water-logging condition, some morphological, anatomical, physiological and biochemical changes take place in plant for the sake of adaptation/survival. Present paper is an overview of physiological, morphological, anatomical, biochemical and molecular changes associated with waterlogging tolerance in sugarcane.

Effect of Nitrogen Addition on the Intra-Annual Leaf and Stem Traits and Their Relationships in Two Dominant Species in a Subtropical Forest

Exploring the relationship between leaf and xylem growth and nitrogen (N) deposition on tree growth helps us better understand how N deposition affects tree growth, but relevant studies are still limited. We tested if leaf and xylem growth and their relationship were affected by N deposition across multiple stages of leaf development. We studied two dominant tree species (Castanopsis chinensis and Schima superba) in a subtropical forest in South China, monitoring their leaf and xylem growth traits under canopy N addition of 0 (CK) and 50 kg N ha−1 year−1 (CAN) and compared these traits and their relationships across different treatments, periods, and species. We found that CAN significantly increased C. chinensis’s leaf carbon (C) content, while the same treatment reduced leaf C content in S. superba. Specific leaf area (SLA), specific leaf weight (SLW), leaf N content, and C:N ratio showed more variation between species and within species across developmental stages than in response to different N addition treatments. Nitrogen addition also significantly increased the xylem width in both species, but the weekly xylem increment before July was notably higher in S. superba than in C. chinensis. Moreover, the leaf C content during early leaf development (ELD) following N addition was significantly and negatively correlated with the start date of xylogenesis in C. chinensis but had no significant effect on the onset of xylogenesis in S. superba. Additionally, regardless of species, SLA in ELD was negatively correlated with xylem width at the end of the early growing season (EW) under CK. However, this relationship became insignificant under CAN, suggesting that N addition alleviated the trade-off between SLA in ELD and EW. These results demonstrated that the relationship between leaf and xylem growth is influenced by both the leaf developmental stage and N availability. Traditional analyses of the leaf–xylem relationship, based solely on mature leaf traits, might oversimplify the effects of N deposition on tree growth.

Unravelling Salinity-induced Growth and Biochemical Changes in Greengram (Vigna radiata L.) with Principal Component Analysis

Background: The impact of global warming on the environment is affecting soil quality and water supplies, which in turn is impacting agricultural production. The rise in salt concentrations in soil and water systems due to increased evaporation rates from warming temperatures and changing precipitation patterns is a major concern. This salinity poses a threat to crop development, especially for sensitive species like the green gram (Vigna radiata L.), a protein-rich legume consumed globally. Understanding the effects of salinity on green gram growth and physiological responses is essential due to its importance as a significant food source. Methods: A pot experiment was conducted at ADACandRI, Trichy, with varying EC values (less than 1, 2, 4, 6, 8, 10 and 12 dS/m) to study the effects of different saline irrigation levels. The experiment utilized the green gram variety VBN 2 in a randomized design with three replications. Growth parameters including plant height, number of leaves and branches, blooming period, root, shoot and leaf lengths were measured. Biochemical characteristics such as protein concentration, reducing sugars, proline and chlorophyll levels were also analyzed. The study evaluated the impact of these characteristics on salinity tolerance using Principal Component Analysis (PCA). Result: Salinity stress negatively affected growth and metabolic reactions in greengram. The VBN 2 variety exhibited better growth and biochemical reactions at a moderate salinity level of 2 dS/m compared to higher salinity levels, indicating moderate salt tolerance. Plant height, leaf growth and flowering time improved with lower salinity levels but decreased significantly at higher salt levels. Important characteristics such as plant height, chlorophyll content and proline accumulation were key factors in determining the plant’s ability to tolerate salt stress, as indicated by PCA analysis.

Leaf traits and insect herbivory levels in two Mediterranean oaks and their hybrids through contrasting environmental gradients.

Insect herbivory has attracted enormous attention from researchers due to its effects on plant fitness. However, there remain questions such as what are the most important leaf traits that determine consumption levels, whether there are latitudinal gradients in herbivore pressure, or whether there are differences in susceptibility between hybrids and their parental species. In this work we address all these issues in two species of Mediterranean Quercus (Q. faginea and Q. pyrenaica) and their hybrids. Over two years, we analyzed leaf emergence and 11 leaf traits (biomechanical, chemical and morphological), as well as the levels of herbivory by insects in leaves of the three genetic groups in different locations distributed along a climatic gradient. The hybrids showed intermediate values ​​between both species in leaf emergence, chemical traits and in structural reinforcement. By contrast, they were more similar to Q. faginea in leaf size and shape. Despite their intermediate leaf traits, hybrids always showed lower losses by consumption than both parental species, which suggests that they possess inherent higher resistance to herbivores, which cannot be explained by their dissimilarities in leaf traits. Within each genetic group, differences in leaf size were the most important determinant of differences in herbivory losses, which increased with leaf size. In turn, leaf size increased significantly with the increase in mean annual temperatures across the climatic gradient, in parallel with herbivory losses. In conclusion, contrary to our expectations, hybrids maintained lower levels of herbivory than their parent species. Given the potential negative effect of leaf herbivory on C fixation, this advantage of the hybrids would imply a threat to the persistence of both pure species. More research is needed to elucidate possible alternative mechanisms that allow maintaining species integrity in the absence of reproductive barriers.

Exogenous 2,4-Epibrassinolide Alleviates Alkaline Stress in Cucumber by Modulating Photosynthetic Performance.

Brassinosteroids (BRs) are recognized for their ability to enhance plant salt tolerance. While considerable research has focused on their effects under neutral salt conditions, the mechanisms through which BRs regulate photosynthesis under alkaline salt stress are less well understood. This study investigates these mechanisms, examining plant growth, photosynthetic electron transport, gas exchange parameters, Calvin cycle dynamics, and the expression of key antioxidant and Calvin cycle genes under alkaline stress conditions induced by NaHCO3. The findings indicate that NaHCO3 stress substantially impairs cucumber growth and photosynthesis, significantly reducing chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), maximum photochemical efficiency (Fv/Fm), actual photochemical efficiency (ΦPSII), antenna conversion efficiency (Fv'/Fm'), and photochemical quenching coefficient (qP). This disruption suggests a severe dysregulation of the photosynthetic electron transport system, impairing electron transfer from photosystem II (PSII) to photosystem I (PSI) and subsequently the Calvin cycle. Application of exogenous 24-epibrassinolide (EBR) alleviated these effects, reducing leaf chlorosis and growth inhibition and significantly enhancing the expression of key genes within the antioxidant system (AsA-GSH cycle) and the Calvin cycle. This intervention also led to a reduction in reactive oxygen species (ROS) accumulation and improved photosynthetic performance, as evidenced by enhancements in Pn, Gs, E, Fv/Fm, ΦPSII, Fv'/Fm', and qP. Moreover, NaHCO3 stress hindered chlorophyll synthesis, primarily by blocking the conversion from porphobilinogen (PBG) to uroporphyrinogen III (UroIII) and by increasing chlorophyllase (Chlase) and decreasing porphobilinogen deaminase (PBGD) activity. Exogenous EBR countered these effects by enhancing PBGD activity and reducing Chlase activity, thereby increasing chlorophyll content under stress conditions. In summary, EBR markedly mitigated the adverse effects of alkaline stress on cucumber leaf photosynthesis by stabilizing the photosynthetic electron transport system, accelerating photosynthetic electron transport, and promoting the Calvin cycle. This study provides valuable insights into the regulatory roles of BRs in enhancing plant resilience to alkaline stress.

Interactive effects of nitrogen deposition and climate change on a globally rare forest geophyte

Abstract Nitrogen (N) deposition and climate change are both known to threaten global biodiversity. However, we still have a limited understanding of how interactions between these global change drivers affect individuals and populations of specialist species, such as geophytes, within their natural habitat. We explored possible interactive effects of N, drought, and warming on population vitality (mean leaf length, leaf density, flowering probability) and morpho‐physiological traits (e.g., leaf and bulb size, N allocation to leaves and bulbs) of the globally rare forest geophyte Gagea spathacea (Liliaceae) in deciduous forests of northern Germany by applying experimental N addition across a climate gradient over a 5‐year period. Mean leaf growth and leaf density were not affected by N addition but were enhanced by warmer and drier conditions in the months before leaf emergence. N addition increased N allocation of individual plants towards their subterranean bulbs. Importantly, effects of N addition on morpho‐physiological traits depended on warming and drought, with N‐fertilized plants showing increased leaf length and decreased specific leaf and bulb N concentration after drier autumns and warmer winters. This indicates that N deposition may partially compensate for increased N demands during warming‐induced growth, although this growth‐promoting interaction effect is not (yet) reflected in population vitality. Our results highlight the importance of considering multiple global environmental change drivers and a whole plant perspective (above‐ and belowground traits) to predict long‐term growth responses of (endangered) forest spring geophytes and to develop adapted long‐term protection strategies.

Experimental analysis of genetic and environmental interactions on leaf elongation and reproductive development in Lolium perenne.

Perennial grasses' reproductive phenology profoundly impacts plant morphogenesis, biomass production, and perenniality in natural ecosystems and cultivated grasslands. Complex interactions between vegetative and reproductive development complicate grass phenology prediction for various environments and genotypes. This work aims to analyse genetic × environment interactions effects on tiller growth and reproductive development in Lolium perenne. Three perennial ryegrass cultivars, Bronsyn, Carvalis, and Tryskal, were grown from seedling to heading under four inductive conditions. T0 plants were continuously exposed to high temperatures and long days (HT-LD). T1, T2, and T3, plants were initially exposed to low temperatures and short days (LT-SD) for 9 weeks. Then, T1 plants were immediately transferred to high temperatures and long days (HT-LD). Before their exposure to HT-LD, T2, and T3 plants were first transferred to high temperatures and short days (HT-SD) for 3 and 6 weeks, respectively. Leaf length, leaf emergence, and heading were regularly monitored. Floral transition and heading only occurred in T1, T2, and T3, i.e. after successive exposure to low temperature and long photoperiod. Bronsyn had higher heading earliness and proportion of reproductive tillers than Carvalis and Tryskal. The duration of HT-SD exposure affected the final number of leaves and spikelets. The rate of leaf and spikelet production significantly increased once plants were exposed to LD. Our results suggest an additive effect of the photoperiod and floral transition on leaf elongation rate. These findings enhance our understanding of the genetic × environment interactions on the vegetative and reproductive development in perennial ryegrass.

THE YIELD OF GARDEN STRAWBERRY DEPENDS ON VARIETAL CHARACTERISTICS IN THE CONDITIONS OF THE FOREST STEPPE OF THE RIGHT BANK

The analysis of studies on the study of the characteristics of the formation of the yield of large-fruited garden strawberries depending on varietal characteristics is presented. The passage of phenological phases of growth and development of strawberry varieties, biometric indicators of plants and products are highlighted. It was established that under the same conditions, the growth of the first leaf was noted earlier in the Rumba and Clary varieties, which is later than the control variety by 1 and 4 days, respectively. The growth of the first peduncle of the Clary variety was recorded on 5.04., and the growth of creeping shoots (whiskers) on 22.05., which is later than the control variety and the Honey variety by 8 days. In the Rumba variety, the flowering phase began on 31.04., and ended on 20.05. The Clary variety was distinguished by the latest terms of the passage of these phenophases – 4.05 beginning of flowering, 23.05 end. In the control variety Olvia, the beginning and of ripening occurred earlier than other varieties. The beginning of ripening of the fruits of this variety was recorded on 19.05., and occurred within 25 days. The Clary variety was characterized by the shortest duration of the fruiting period – 18 days. Previously, the beginning of ripening of garden strawberries was recorded in the Olvia variety – 19.05, which is 2-10 days earlier than the studied assortment. The latest this phase was noted in the Clary variety – 29.05, which indicates a later ripening period of the berries. The end of ripening of large-fruited garden strawberries was recorded the latest in the Rumba variety – 21.06, which is 8 days later than the control (Olvia variety), therefore, fruiting in this studied variety lasted the longest – 26 days. The average fruit weight at the first harvest of the Rumba variety was 34.3 g, which was 5.7 g more than the control variety. The varieties Honey and Clary had a greater weight than the control variety Olvia by 1.5 and 2.8 g, respectively. The average weight of its fruits across all harvests was 15.1 g. The varieties Honey and Clary had an average weight across all harvests of 16.5 and 17.6 grams. The largest average fruit weight across harvests was recorded for the Rumba variety – 22.3 g, which characterized its varietal feature as a large-fruited variety. The ability of the Rumba variety to form a larger leaf surface area – 17.7 m2/ha, positively affected the ability of this variety to form larger fruits. The formation of a leaf surface area of 16.1 and 16.3 thousand was recorded for the varieties Honey and Clary. m2/ha, which exceeded the indicators of the control variant by 0.8-1.0 g, respectively. The Clery variety formed a greater number of cones – 9.7 pcs/bush, and a greater number of peduncles – 5.9 pcs/bush, which exceeded the control variant and by 1.5 and 1.1 pcs/bush, respectively. In the Rumba variety, 1.1 pcs/bush less number of cones and 1 pc/bush less number of peduncles were recorded than in the Clery variety. The Rumba variety turned out to be the most productive and, accordingly, with a higher indicator of product marketability – 83.7 %. Its yield was – 24.5 t/ha, which exceeded the indicator of the control variety Olvia by 15.9 t/ha. The second variety in terms of yield was the Clery variety – 18.4 t/ha with a marketability of 82.3 %. These productivity indicators of the variety are higher than those of the Honey variety by 6.8 t/ha, and compared to the Olvia variety (control) by 9.8 t/ha. The yield of marketable products of the Clery and Honey varieties was 82.3 and 81.4 %, respectively.

Optimizing Cabbage Cultivation in Paddy-Converted Fields Using Discarded Coir Substrates and Controlled Irrigation

This study aimed to reuse discarded coir substrates and optimize irrigation as a low-cost solution for addressing waterlogging in paddy-converted farmland. We employed a 2 × 4 factorial design, with the growth substrates consisting of paddy soil (PS) and coir substrates (CSs), and four irrigation levels (ILs) set as 140% crop evapotranspiration (ETc140), 100% ETc (ETc100), 60% ETc (ETc60), and non-irrigated control (ETc0). We evaluated the growth and physiological characteristics of cabbage (Brassica oleracea L. var. Capitata), including the outer leaf growth, yield components, water use efficiency (WUE), photosynthetic parameters, chlorophyll content, proline content, malondialdehyde (MDA) content, and glucosinolates (GLs) content. The results indicated that the interaction between the CSs and IL significantly improved cabbage growth, photosynthetic activity, and stress resistance compared with PS. Notably, when CS was combined with ETc100 and ETc60 irrigation levels, cabbage exhibited optimal growth parameters, and CS-ETc60 achieved the highest WUE. This study indicated that using discarded coir substrates combined with appropriate irrigation levels offers an effective and low-cost solution for mitigating waterlogging problems.

The Ameliorative Effect of Coumarin on Copper Toxicity in Citrus sinensis: Insights from Growth, Nutrient Uptake, Oxidative Damage, and Photosynthetic Performance.

Excessive copper (Cu) has become a common physiological disorder restricting the sustainable production of citrus. Coumarin (COU) is a hydroxycinnamic acid that can protect plants from heavy metal toxicity. No data to date are available on the ameliorative effect of COU on plant Cu toxicity. 'Xuegan' (Citrus sinensis (L.) Osbeck) seedlings were treated for 24 weeks with nutrient solution containing two Cu levels (0.5 (Cu0.5) and 400 (Cu400) μM CuCl2) × four COU levels (0 (COU0), 10 (COU10), 50 (COU50), and 100 (COU100) μM COU). There were eight treatments in total. COU supply alleviated Cu400-induced increase in Cu absorption and oxidative injury in roots and leaves, decrease in growth, nutrient uptake, and leaf pigment concentrations and CO2 assimilation (ACO2), and photo-inhibitory impairment to the whole photosynthetic electron transport chain (PETC) in leaves, as revealed by chlorophyll a fluorescence (OJIP) transient. Further analysis suggested that the COU-mediated improvement of nutrient status (decreased competition of Cu2+ with Mg2+ and Fe2+, increased uptake of nutrients, and elevated ability to maintain nutrient balance) and mitigation of oxidative damage (decreased formation of reactive oxygen species and efficient detoxification system in leaves and roots) might lower the damage of Cu400 to roots and leaves (chloroplast ultrastructure and PETC), thereby improving the leaf pigment levels, ACO2, and growth of Cu400-treated seedlings.

Xanthan gum/ZrMOF biodegradable gel fertilizer: Sustainable water retention and crop growth.

To address the problems of ecological pollution and food safety caused by the excessive use of chemical fertilizers in modern agriculture, it has become a hot topic of current research to develop novel low-cost, biodegradable, and efficient gel slow-release fertilizers. Herein, using xanthan gum and ZrMOF as raw materials, urea as a nutrient, acrylic acid and itaconic acid as co-monomers, a novel ZrMOF gel slow-release fertilizer (ZrMOF@CpM) was prepared by free radical copolymerization. After being characterized, its swelling and water retention properties and slow-release behavior were investigated. It was demonstrated that ZrMOF@CpM with a high surface area and mesoporous structure provided rich water and fertilizer channels for slow-release fertilizer. Therefore, beside good water absorption (260.7 g/g) and water retention, its nutrient (N) slow-release performance (45 d, 49.1 %) was in accordance with the Committee for European Normalization (CEN) standards. The slow-release gel fertilizer also showed good degradation performance (35 d, 56.9 %). Additionally, maize pot trials showed that the synthesized slow-release fertilizer materials significantly promoted plant root and leaf growth. Overall, we provide a new strategy for the construction of high-efficiency, high-water retention and biodegradable agricultural gel slow-release fertilizers.

Bacterial community function increases leaf growth in a pitcher plant experimental system.

This study addresses a gap in understanding the relationships between bacterial community function and plant growth. We inoculated sterile, freshly opened pitcher plant leaves with three functionally distinct bacterial communities to uncover potential mechanisms through which bacterial functions support plant health and growth. Our findings demonstrate that distinct community functions significantly influence plant traits, with some bacterial communities supporting more plant growth than in control pitchers. These results highlight the ecological roles of microbial communities in plants and thus ecosystems and suggest that nutrient cycling is an important pathway through which microbes support host plant health. This research provides valuable insights into plant-microbe interactions and the effects of diverse microbial community functions.