Leaf Size Research Articles

Unraveling Morphological, Physiological, and Transcriptomic Alterations Underlying the Formation of Little Leaves in Phytoplasma-Infected Sweet Cherry Trees.

Phytoplasmas are minute phytopathogenic bacteria that induce excessive vegetative growth, known as witches'-broom (WB), in many infected plant species during the later stages of infection. The WB structure is characterized by densely clustered little (small) leaves, which are frequently accompanied by chlorosis (yellowing). The mechanisms behind the formation of little leaves within WB structures (LL-WB) are poorly understood. To address this gap, the LL-WB formation was extensively studied using sweet cherry virescence (SCV) phytoplasma-infected sweet cherry plants. Based on morphological examinations, signs of premature leaf senescence were observed in LL-WB samples, including reduced leaf size, chlorosis, and alterations in shape. Subsequent physiological analyses indicated decreased sucrose and glucose levels and changes in hormone concentrations in LL-WB samples. Additionally, the transcriptomic analysis revealed impaired ribosome biogenesis and DNA replication. As an essential process in protein production, the compromised ribosome biogenesis and the inhibited DNA replication led to cell cycle arrest, thus affecting leaf morphogenesis and further plant development. Moreover, the expression of marker genes involved in premature leaf senescence was significantly altered. These results indicate a complicated interplay between the development of leaves, premature leaf senescence, and the pathogen-induced stress responses in SCV phytoplasma-infected sweet cherry trees. The results of this study provide insight into understanding the underlying molecular mechanisms driving the formation of little leaves and interactions between plants and pathogens. The findings might help control phytoplasma diseases in sweet cherry cultivation.

Morphological Evaluation of Locally Available Cultivated Taro (Colocasia esculenta) Cultivars for Growth and Yield Attributes in Kokrajhar, Assam, India

Taro probably is one of the world’s oldest crop and important crop species in the district but its cultivation and consumption still lie within the less privileged farmers in Kokrajhar district of Assam, India. It is cultivated for its tubers, tender leaves and inflorescence. It is also observed that several morphological types are found in upland and hilly slopes of the district, but their identification and morphological studies are not very clear, and their agronomic potentiality further needs to be analysed. Under such situations, a study has been taken to evaluate all the local varieties namely Pehle, Abor, Daomasar, Deraduma and Tharun gubwi in terms of yield and other agronomic parameters for proper documentation of genetic diversity and differentiation in the district. The trial was laid out in a randomized complete block design with three replications. The study was conducted in Debitola and Kachugaon blocks of Kokrajhar district. The results indicated significant differences for all the characteristics studied. ‘Tharun gubwi’ recorded highest value for plant height (134.4cm), leaf size (2244.0 cm2), corm breadth (8.10cm), average corm weight (2036.00g) and average yield (2248.33g/plant). Petiole length was recorded highest in Cv. Deraduma (95.23 cm). Cv. Daomasar was recorded with maximum plant spread of 144.5 cm and numbers of side shoots (5.67 nos.). Highest corm length (20.23cm), cormel length (13.24cm) and cormel weight (98.25g) was recorded maximum in Cv. Abor. Results revealed that all these local cultivars have good agronomic importance therefore, various developmental programmes are need to be undertaken for popularizing it to every corner of the state and country

Molecular characterization to study the genetic diversity of begomoviruses occurring in the major chilli growing areas of Tamil Nadu state of India.

Chilli leaf curl disease (ChiLCD), which is a significant problem in chilli cultivation, is caused by begomoviruses that are transmitted by the whitefly Bemisia tabaci. This disease leads to severe impacts on crop yields. To determine the incidence of begomovirus in the chilli crop, infected chilli leaf samples exhibiting symptoms such as curling, yellowing, reduced leaf size, and overall stunted growth were collected from various districts of Tamil Nadu, namely, Coimbatore, Dharmapuri, Kancheepuram, Karur, Salem, Krishnagiri, Thoothukudi, Thiruvallur, Tiruchirappalli, Virudhunagar, Tiruvannamalai, Tenkasi, and Vellore, during the years 2018-2022. To determine the complete genome sequence of the begomoviruses, the rolling circle amplification (RCA) method was used to clone and sequence thebegomovirus genomes from the chilli samples collectedfrom various districts of Tamil Nadu. Here we characterized 17 DNA A genome sequences and 12 betasatellite sequences. BLAST results of the DNA A genome sequences revealed nucleotide identities ranging from 94.2 to 99.7% with five distinct begomovirus species of chilli, namely, chilli leaf curl Salem virus (HM007119), chilli leaf curl virus Bhavanisagar (NC_055130), chilli leaf curl Ahmedabad virus (MW795666), chilli leaf curl virus (NC_055131), and chilli leaf curl Sri Lanka virus (JN555600). BLAST results of the betasatellite sequences showed nucleotide identities of 96 to 98.8% with the tomato leaf curl Bangladesh betasatellite (MZ151286). In the present study, five distinct begomovirus species and one associated betasatellite were found to infect chilli crops in Tamil Nadu. This finding indicates a changing pattern of begomovirus occurrence in the different districts of Tamil Nadu. This study highlights the prevalence of chilli-infecting begomoviruses in the major chilli growing districts of Tamil Nadu, the identification of begomovirus species, and the significance of understanding and managing these viruses to safeguard chilli cultivation in the region.

Enhancing genetic diversity in Pelargonium: insights from crossbreeding in the gene pool.

This study aimed to enrich the Pelargonium gene pool through crosses and assess genetic variation among 56 genotypes from five Pelargonium species. Seventeen morphological descriptors were used, and NTSYS-pc software was employed to define genetic relationships, and a UPGMA-generated dendrogram reflected these relationships. Moreover, principal component analysis (PCA) was performed to determine which parameter was more effective in explaining variation. Results showed wide variation in genetic similarity rates, with the most similar genotypes being P. zonale 'c1' and a hybrid of P. zonale 'c1' x P. zonale 'c2' (90% similarity). According to the dendrogram results, it was observed that the genotypes were distributed in six clusters. In contrast, the most distant genotypes were P. zonale 'c11' and a hybrid of P. zonale 'c10' x P.zonale 'c11' (0.04% similarity). Hybrids from the female parent P. x hortorum 'c1' exhibited unique placement in the dendrogram. In the crossing combinations with this genotype, the individuals obtained in terms of flower type, flower color, flower size, bud size, early flowering, and leaf size characters showed different characteristics from the parents. Surprising outcomes in flower types, colors, and shapes contributed to gene pool enrichment, promising increased breeding variation success. The study holds practical implications for commercial breeding and serves as a valuable guide for future research endeavors.

Canopy temperatures strongly overestimate leaf thermal safety margins of tropical trees.

Current estimates of temperature effects on plants mostly rely on air temperature, although it can significantly deviate from leaf temperature (Tleaf). To address this, some studies have used canopy temperature (Tcan). However, Tcan fails to capture the fine-scale variation in Tleaf among leaves and species in diverse canopies. We used infrared radiometers to study Tleaf and Tcan and how they deviate from air temperature (ΔTleaf and ΔTcan) in multispecies tropical tree plantations at three sites along an elevation and temperature gradient in Rwanda. Our results showed high Tleaf (up to c. 50°C) and ΔTleaf (on average 8-10°C and up to c.20°C) of sun-exposed leaves during 10:00 h-15:00 h, being close to or exceeding photosynthetic heat tolerance thresholds. These values greatly exceeded simultaneously measured values of Tcan and ΔTcan, respectively, leading to strongly overestimated leaf thermal safety margins if basing those on Tcan data. Stomatal conductance and leaf size affected Tleaf and Tcan in line with their expected influences on leaf energy balance. Our findings highlight the importance of leaf traits for leaf thermoregulation and show that monitoring Tcan is not enough to capture the peak temperatures and heat stress experienced by individual leaves of different species in tropical forest canopies.

Effect of Pinus halepensis Mill. Reforestation on the Above-Ground Biomass and Internode Elongation and Leaf Size of Native Species in Morroco

This study aims to determine the effect of the reforestation of Pinus halepensis Mill. on the above-ground biomass and morphological characteristics of native species (internode elongation and leaf size) in the Beni Sohane forest. Plant biomass of the herbaceous layer was harvested on randomly selected 2 m2 quadrats in reforested plots of ± 12, ± 25, and ± 45-year-old, and native forest controls. The internode length and leaf size (length and width) were measured on plants randomly selected belonging to four native species Quercus ilex L., Pistacia lentiscus L., Phillyrea angustifolia L., and Cistus creticus L.. The results showed that P. halepensis reforestation had no significant effect on the above-ground biomass and the leaves and internodes dimensions in the young plantations ± 12-year-old. However, as the pine trees mature, the average dry matter weight decreases, especially in stands 45 years old, where this weight was significantly lower than that of natural forests. This fact has led to herders abandoning important pastures previously used by their cattle. In addition, the fast growth of P. halepensis trees formed a canopy above all indigenous species resulting in changes in the dimensions of internodes and leaves. For the two oldest plantations, the internode length, leaf width, and length of the 4 species have been significantly increased. However, the leaf length-to-width ratio decreased significantly, with leaves in reforested plots being larger rather than longer compared to control samples in native forests. Planting P. halepensis can negatively impact the long-term growth of native plants, so we recommend periodically removing some of the pines (thinning) to restore the balance of these ecosystems. Thus, species selection for reforestation should consider maximizing rather than destroying ecological and socioeconomic services.

Effect of Pinus halepensis Mill. Reforestation on the Above-Ground Biomass and Internode Elongation and Leaf Size of Native Species in Morroco

This study aims to determine the effect of the reforestation of Pinus halepensis Mill. on the above-ground biomass and morphological characteristics of native species (internode elongation and leaf size) in the Beni Sohane forest. Plant biomass of the herbaceous layer was harvested on randomly selected 2 m2 quadrats in reforested plots of ± 12, ± 25, and ± 45-year-old, and native forest controls. The internode length and leaf size (length and width) were measured on plants randomly selected belonging to four native species Quercus ilex L., Pistacia lentiscus L., Phillyrea angustifolia L., and Cistus creticus L.. The results showed that P. halepensis reforestation had no significant effect on the above-ground biomass and the leaves and internodes dimensions in the young plantations ± 12-year-old. However, as the pine trees mature, the average dry matter weight decreases, especially in stands 45 years old, where this weight was significantly lower than that of natural forests. This fact has led to herders abandoning important pastures previously used by their cattle. In addition, the fast growth of P. halepensis trees formed a canopy above all indigenous species resulting in changes in the dimensions of internodes and leaves. For the two oldest plantations, the internode length, leaf width, and length of the 4 species have been significantly increased. However, the leaf length-to-width ratio decreased significantly, with leaves in reforested plots being larger rather than longer compared to control samples in native forests. Planting P. halepensis can negatively impact the long-term growth of native plants, so we recommend periodically removing some of the pines (thinning) to restore the balance of these ecosystems. Thus, species selection for reforestation should consider maximizing rather than destroying ecological and socioeconomic services.

Variation and Phenetic Relationship of Passiflora spp. in Yogyakarta Based on Morphological and Anatomical Characters

Passiflora spp. or passion fruit is a tropical plant that is often used as a food source. The large morphological variations of Passiflora cause difficulties in identifying the species. The objectives of the study are to identify the specific morphological and anatomical characters of Passiflora spp. in Yogyakarta and to determine their phenetic relationship for identification. A total of 15 samples of Passiflora were taken by purposive sampling technique from Bantul, Sleman, Kulon Progo, and Yogyakarta City, and then carried through the morphological and anatomical characterization. The morphological characters observed stems, leaves, and flowers, while the anatomical characters observed leaves. The results show that the observed samples are identified as four species, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis. The P. edulis species consists of two forms, P. edulis f. flavicarpa and P. edulis f. edulis. The variation of morphological character lie in young stem shape, leaf shape, the texture of stem and leaf surface, bract shape and color, sepal and petal color, and the presence of a purple corona ring. While the variation of anatomical characters lie in the pattern of the vascular bundles, the shape of the upper and lower sides of the leaf veins, the shape and size of the palisade cells, as well as the type and density of stomata. Based on the phenetic analysis on the 0.8 phenon line, four main clusters were formed, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis.

Effect of arbuscular mycorrhizal fungi as fungal biofertilizer on the growth and yield of okra (Abelmoschus Esculentus l.) in Kebbi

Studies on effect of arbuscular mycorrhizal fungi of biofertilizer on growth and yield Okra (Abelmoschus esculentus L).The study was carried out in the greenhouse, the department of biology ADAMU AUGIE COLLEGE OF EDUCATION ARGUNGU in polythene bags (50g). A total of 420 seeds of Okra were collected from national cereals Research Institute Gwadangaji. A sun dried seeds of the samples was sown in polythene bags and distributed into seven treatments which were used in the study as follows, control (without treatment), biofertilizer only, organic fertilizer only, chemical fertilizer only, organic fertilizer + biofertilizer, 20% chemical fertilizer + biofertilizer, and biofertilizer (two doses). Using complete randomized block design (CRBD). From the result shows that the biofertilizer only in all parameters shows significant differences (P< 0.05) compared with the control, which gives an indication that biofertilizer helped plant growth and been able to provide the plants with nutrients as it promoted rapid growth, increased leaf size, leaf length, number of leaves, number of branches, fresh weight and dry weight of the plant, hastened crop maturity, and promote fruit and seed development. It was concluded from the result of the study that a fungal biofertilizer play a role as biofertilizer. Were it is clear that the use of biofertilizer affect the growth of Okra. Biofertilizer (two doses) do not affect the growth of Okra as biofertilizer (one dose).It may be due to competition of fungi. The combination of treatments with biofertilizer were recommended for the optimum growth and the yield of Okra. The experiment may be repeated using another fungi or mixture of different fungi. Potassium solubilizing fungi, phosphate solubilizing fungi or another N-fixing microorganism. Cultivation of the plants in field instead of the polythene bags, to provide an appropriate environment to the fungi.

Regulating Leaf Photosynthesis and Soil Microorganisms through Controlled-Release Nitrogen Fertilizer Can Effectively Alleviate the Stress of Elevated Ambient Ozone on Winter Wheat.

The mitigation mechanisms of a kind of controlled-release nitrogen fertilizer (sulfur-coated controlled-release nitrogen fertilizer, SCNF) in response to O3 stress on a winter wheat (Triticum aestivum L.) variety (Nongmai-88) were studied in crop physiology and soil biology through the ozone-free-air controlled enrichment (O3-FACE) simulation platform and soil microbial metagenomics. The results showed that SCNF could not delay the O3-induced leaf senescence of winter wheat but could enhance the leaf size and photosynthetic function of flag leaves, increase the accumulation of nutrient elements, and lay the foundation for yield by regulating the release rate of nitrogen (N). By regulating the soil environment, SCNF could maintain the diversity and stability of soil bacterial and archaeal communities, but there was no obvious interaction with the soil fungal community. By alleviating the inhibition effects of O3 on N-cycling-related genes (ko00910) of soil microorganisms, SCNF improved the activities of related enzymes and might have great potential in improving soil N retention. The results demonstrated the ability of SCNF to improve leaf photosynthetic function and increase crop yield under O3-polluted conditions in the farmland ecosystem, which may become an effective nitrogen fertilizer management measure to cope with the elevated ambient O3 and achieve sustainable production.

Genetic Evidence of SpGH9A3 in Leaf Morphology Variation of Spathiphyllum 'Mojo'.

Leaves play a crucial role as ornamental organs in Spathiphyllum, exhibiting distinct differences across various Spathiphyllum varieties. Leaf development is intricately linked to processes of cell proliferation and expansion, with cell morphology often regulated by plant cell walls, primarily composed of cellulose. Alterations in cellulose content can impact cell morphology, subsequently influencing the overall shape of plant organs. Although cellulases have been shown to affect cellulose levels in plant cells, genetic evidence linking them to the regulation of leaf shape remains limited. This study took the leaves of Spathiphyllum 'Mojo' and its somatic variants as the research objects. We screened four cellulase gene family members from the transcriptome and then measured the leaf cellulose content, cellulase activity, and expression levels of cellulase-related genes. Correlation analysis pinpointed the gene SpGH9A3 as closely associated with leaf shape variations in the mutant. Green fluorescent fusion protein assays revealed that the SpGH9A3 protein was localized to the cell membrane. Notably, the expression of the SpGH9A3 gene in mutant leaves peaked during the early spread stage, resulting in smaller overall leaf size and reduced cellulose content upon overexpression in Arabidopsis.

Jackfruit Genotypes in Southern Nayarit: A Comparative Study of Morphological, Physiological, Physicochemical, Phytochemical, and Molecular Assessments

Jackfruit, primarily cultivated in Nayarit, Mexico, has four notable genotypes: “Agüitada”, “Rumina”, “Licenciada”, and “Karlita”, which require thorough characterization. This study aimed to provide a comprehensive characterization of these genotypes through an integration of morphological, physiological, physicochemical, phytochemical, and DNA fingerprinting analyses. Measurements were taken from physiological maturity to senescence. SSR and SRAP markers were employed for DNA fingerprinting, and a complete randomized design followed by multivariate analysis was used to observe variable relationships. The results revealed that “Rumina” had the largest leaf size, while “Karlita” had the largest fruit size and the highest respiration rate (117.27 mL of CO2·kg−1·h−1). “Licenciada” showed the highest ethylene production (265.45 µL·kg−1·h−1). “Agüitada” and “Licenciada” were associated with orange bulbs, whereas “Rumina” and “Karlita” were associated with yellow ones. Additionally, “Agüitada” demonstrated higher levels of soluble phenols and carotenoids, indicating greater antioxidant capacity. The Jaccard index suggested moderate genetic diversity among the genotypes, and the dendrogram revealed two genetic clusters. “Licenciada” emerged as a promising genotype, combining high genetic diversity with desirable physicochemical traits. This study highlights the need to broaden future genetic analyses to include a wider range of jackfruit genotypes from various regions, offering a more comprehensive understanding of genetic diversity.

ORANGE interplays with TCP7 to regulate endoreduplication and leaf size.

Leaf size is a crucial agronomic trait directly affecting crop yield, which is mainly determined by coordinated cell proliferation, growth, and differentiation. Although endoreduplication is known to be correlated with the onset of cell differentiation and leaf size, the underlying molecular mechanisms are largely unclear. The DnaJ-like zinc finger domain-containing protein ORANGE (OR) was initially demonstrated to confer the massive accumulation of carotenoids in cauliflower curds. However, the cauliflower or mutant also possesses other phenotypes such as smaller curds, smaller leaves with elongated petioles, and delayed flowering. Here, we demonstrated that OR physically interacts with the transcription factor TCP7, which promotes endoreduplication by inducing the expression of the cell cycle gene CYCLIN D 1;1 (CYCD1;1). Overexpression of OR resulted in smaller rosette leaves, whereas the OR-silencing plants had larger rosette leaves than wild-type plants. Our microscopic observations and flow cytometry analysis revealed that the variation in leaf size was a result of different endoreduplication levels. Genetic analyses showed that OR functions antagonistically with TCP7 in regulating the endoreduplication levels in leaf cells. While the expression of OR is induced by TCP7, OR represses the transactivation activity of TCP7 by affecting its binding capability to the TCP-binding motif in the promoter region of CYCD1;1. Through this interaction, OR negatively regulates the expression of CYCD1;1 and reduces the nuclear ploidy level in rosette leaf cells. Our findings provide new insights into the regulatory network of leaf size and also reveal a regulatory circuit controlling endoreduplication in leaf cells.

The Population of the Glacial Relict Betula nana Surviving Anthropogenic Pressure (the Case of Šepeta Peatland in Northeastern Lithuania)

The main objective of the study was to evaluate the population characteristics of Betula nana under different anthropogenic influences. The study was conducted in the vicinity of the exploited Šepeta peatland (northeastern Lithuania). The population status of B. nana was determined by comparing the ramet density and morphology (height, branching, and leaf size), the age structure, the number of generative ramets, and their flowering characteristics in four study areas at different distances from the exploited peatlands and in different habitats. Around 20 environmental factors were included in the analysis, covering water levels, peat, and vegetation characteristics. Shading, drainage and increased amounts of nitrogen in the habitats are the main factors contributing to the differences and structure of B. nana cenopopulations. Although taller ramets with larger leaves are observed under the changed conditions as an adaptation to shading, the negative anthropogenic effects in the most affected habitats are reflected in a reduction in the number of flowering ramets, lower vegetative regeneration, and an increase in the number of dead twigs on mature ramets.

The "Leafing Intensity Premium" Hypothesis and the Scaling Relationships of the Functional Traits of Bamboo Species.

The "leafing intensity premium" hypothesis proposes that leaf size results from natural selection acting on different leafing intensities, i.e., the number of leaves per unit shoot volume or mass. The scaling relationships among various above-ground functional traits in the context of this hypothesis are important for understanding plant growth and ecology. Yet, they have not been sufficiently studied. In this study, we selected four bamboo species of the genus Indocalamus Nakai and measured the total leaf fresh mass per culm, total non-leaf above-ground fresh mass, total number of leaves per culm, and above-ground culm height of 90 culms from each species. These data were used to calculate leafing intensity (i.e., the total number of leaves per culm divided by the total non-leaf above-ground fresh mass) and mean leaf fresh mass per culm (i.e., the total leaf fresh mass per culm divided by the total number of leaves per culm). Reduced major axis regression protocols were then used to determine the scaling relationships among the various above-ground functional traits and leafing intensity. Among the four species, three exhibited an isometric (one-to-one) relationship between the total leaf fresh mass per culm and the total non-leaf above-ground fresh mass, whereas one species (Indocalamus pumilus) exhibited an allometric (not one-to-one) relationship. A negative isometric relationship was found between the mean leaf fresh mass per culm and the leafing intensity for one species (Indocalamus pedalis), whereas three negative allometric relationships between mean leaf fresh mass per culm and leafing intensity were observed for the other three species and the pooled data. An exploration of the alternative definitions of "leafing intensity" showed that the total number of leaves per culm divided by the above-ground culm height is superior because it facilitates the non-destructive calculation of leafing intensity for Indocalamus species. These results not only confirm the leafing intensity premium hypothesis for bamboo species but also highlight the interconnected scaling relationships among different functional traits, thereby contributing to our understanding of the ecological and evolutionary significance of leaf size variation and biomass investment strategies.

HvWOX3A Gene Controls Plant Height and Leaf Size in Barley

HvWOX3A Gene Controls Plant Height and Leaf Size in Barley

Rapid morphological change in UK populations of Impatiens glandulifera

The highly invasive Impatiens glandulifera (Himalayan balsam) is one of the most prolific and widespread invasive plants in the British Isles. Introduced in the early nineteenth century, it has now been reported in almost every vice county across the UK and is a fierce competitor that has adverse effects on the local community structure. Despite the negative impacts that invaders like I. glandulifera have on local communities, there have been very few studies which address the morphological changes that invasive plant populations have undergone since their initial introduction. This is the first study of its kind to investigate the morphological changes that have occurred in I. glandulifera. 315 herbarium specimens dating from 1865 to 2017 were used to measure changes in morphological traits such as leaf size, flower length and stomatal characteristics. We found that since 1865, there has been a significant reduction in overall leaf size, a significant reduction in stomatal density and a significant increase in the overall flower length. These results highlight the importance of monitoring the evolutionary change in prolific alien species over the course of their invasion, providing useful insights into changes in competitive ability which may prove useful in managing dispersal and providing options for potential management.

Specific leaf area and its within-individual variation in understory evergreen and deciduous woody species in New Zealand

Specific leaf area (SLA) plays a critical role in carbon assimilation and nutrient cycling. While leaf habit (deciduous vs. evergreen) has often been recognized as a reliable predictor of SLA—with deciduous species typically having higher mean SLA values due to lower concentration of structural components compared to evergreens—high variation in SLA among evergreen species suggests further investigation of variation for species with this leaf habit could improve predictions of SLA effects on community and ecosystem processes. Furthermore, the presence of leaves of different ages in evergreen plants, emerging over multiple years, could amplify the within-individual variation in SLA, which remains underexplored. Here we report variations of SLA measured from c. 2000 leaves collected from 36 individuals across 19 woody species in an understory environment in New Zealand (NZ). We found that while most deciduous species, predominantly non-native, clustered towards higher SLA values, evergreen species presented a wide SLA spectrum. Moreover, we found that while being deciduous, having a smaller leaf size, and younger leaves, collected from lateral branches, correlated with elevated SLA values, the leaf habit did not primarily drive the within-individual SLA variation. Instead, smaller leaf size emerged as a significant predictor of within-individual SLA variation. The branch-order effect on SLA underscores a methodological consideration: accurate estimation of total leaf area in evergreen trees requires representative sampling across all branch orders. Our study also highlights the need for integrating leaf traits such as leaf size and branch order into functional trait analyses. Further research is vital to understand the underlying mechanisms of these trait variations and their impacts on ecosystem functioning.

Individual Protective Covers Improve Yield and Quality of Citrus Fruit under Endemic Huanglongbing.

The use of individual protective covers (IPCs) to protect newly planted citrus trees from Huanglongbing (HLB) infection is being widely adopted in Florida, an HLB-endemic citrus-producing area. It is known that IPCs positively influence most horticultural traits, increasing tree growth, flush expansion, and leaf size, enabling trees to sustain balanced carbohydrate metabolism by preventing Candidatus Liberibacter asiaticus (CLas) infection, and inducing higher leaf chlorophyll levels. This may result in more productive trees. However, as the tree grows, IPCs eventually are removed, typically between 2 and 3 years after their initial installation. Once IPCs are removed, trees become exposed to the Asian citrus psyllid (ACPs) and ultimately become infected. In this work, we covered Valencia sweet orange trees with IPCs for 30 months, until the trees entered fruit-bearing age. We investigated how the IPC protection of newly planted trees for 30 months influenced the fruit quality and yield of "Valencia" trees for three consecutive seasons after IPC removal compared to non-covered trees. The use of IPCs kick-started the newly planted citrus trees, resulting in higher yields and fruits with better internal and external quality. After 30 months of IPC protection, tree canopies were larger and denser, supporting more fruit per tree than non-protected trees for three consecutive seasons, even though by the end of the first season after IPC removal, the trees were HLB-positive. Tree height, scion diameter, canopy volume, and leaf area were significantly improved compared to non-covered trees. Additionally, fruit quality was significantly improved in the three seasons following IPC removal compared to non-covered trees. However, a decline in quality was measurable in fruit from IPC trees after the second harvesting season, with trees affected by HLB. Based on the results from this study, we conclude that the benefits from IPC protection may last for at least three consecutive seasons once trees enter the productive age, despite CLas infection within 12 months after IPC removal.

Single-plant-omics reveals the cascade of transcriptional changes during the vegetative-to-reproductive transition.

Plants undergo rapid developmental transitions, which occur contemporaneously with gradual changes in physiology. Moreover, individual plants within a population undergo developmental transitions asynchronously. Single-plant-omics has the potential to distinguish between transcriptional events that are associated with these binary and continuous processes. Furthermore, we can use single-plant-omics to order individual plants by their intrinsic biological age, providing a high-resolution transcriptional time series. We performed RNA-seq on leaves from a large population of wild-type Arabidopsis (Arabidopsis thaliana) during the vegetative-to-reproductive transition. Though most transcripts were differentially expressed between bolted and unbolted plants, some regulators were more closely associated with leaf size and biomass. Using a pseudotime inference algorithm, we determined that some senescence-associated processes, such as the reduction in ribosome biogenesis, were evident in the transcriptome before a bolt was visible. Even in this near-isogenic population, some variants are associated with developmental traits. These results support the use of single-plant-omics to uncover rapid transcriptional dynamics by exploiting developmental asynchrony.