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Background Pear tree nutrient requirements vary across growth stages. The spatial distributions of soil nutrients and microbial communities were analyzed to elucidate the nutrient demands at different growth stages, investigate the relationship between soil microorganisms and nutrients, and provide a theoretical basis for fertilization and soil management practices in pear orchards. Results Distinct temporal and spatial patterns in nutrient dynamics were observed. With increasing tree age, the leaf calcium (Ca) content initially increased then decreased, peaking at 30.96 g·kg⁻ 1 in 46-year-old trees. The leaf copper (Cu) content progressively increased, reaching its highest concentration (15.16 mg·kg⁻ 1 ) in trees (> 100 years). The relative abundances of key bacterial phyla,  Actinobacteria  and  Acidobacteria , reached their maxima (19.88% and 20.4%, respectively) in 4-year-old orchards before slightly declining. Spatial analysis of mature orchards revealed that the soil phosphorus (P) and potassium (K) contents decreased with increasing distance from the tree trunk, whereas the boron (B), zinc (Zn), and manganese (Mn) contents increased. Comparative analysis with adjacent long-term unplanted soils revealed that pear tree cultivation significantly depleted soil Ca, magnesium (Mg), iron (Fe), and Mn, whereas Cu and Zn levels increased, suggesting a high tree demand for the former group and an application rate of Cu and Zn fertilizers exceeding the tree absorption capacity. Within tree tissues, the nitrogen (N) and P contents were highest in 1- and 2-year-old branches, whereas Ca, Mg, Fe, B, and Mn accumulated predominantly in perennial old roots. Significant positive correlations were identified between several leaf and soil elements. Furthermore, soil nutrient availability was linked to microbial diversity: soil P and Zn contents were positively correlated with the bacterial aroma index. Soil Mg, Cu, and Zn were positively correlated with the bacterial ACE index; and the soil N content was positively correlated with the fungal Simpson index. Conclusion Soil microbial communities in pear orchards are associated with P, Ca, and Zn. Nutrient elements in pear trees such as Ca, Mn, B, Mg, and Fe, which are difficult to transport and tend to accumulate in root tissues; thus, foliar application is recommended for their supplementation.

Background Nutrient limitation is a universal phenomenon in terrestrial ecosystems. Root and mycorrhizal are critical to plant nutrient absorption in nutrient-limited ecosystems. However, how they are modified by N and P limitations with advancing vegetation successions in karst forests remains poorly understood. The present study compared the diversity indices, composition, and co-occurrence network of arbuscular mycorrhizal fungi (AMF) between grassland, shrubland, shrub-tree forest, and tree forest in subtropical karst forests, as well as soil nutrients and fine root functional traits (e.g., specific root length (SRL), specific root area (SRA), diameter, biomass, and N and P contents). Results The fine roots diameter, biomass, and N and P contents increased with advancing succession, whereas SRL and SRA decreased. Network complexity and Richness and Chao1 indices of AMF increased from grassland to shrub-tree forest but decreased in tree forest. The fine roots N and P contents were positively related to their diameter and biomass, soil nutrients, and AMF composition but were negatively correlated with SRL and SRA. Moreover, these two parameters increased with the increase of soil nutrients. The variations in fine roots N and P contents were mainly explained by soil nutrients and fine root functional traits in grassland and by the interactions of soil nutrients, fine root functional traits, and AMF in the other three stages. Additionally, the interactive explanation with AMF increased from shrubland to shrub-tree forest but decreased in tree forest. Conclusions Our results indicated that mycorrhizal strategy might be the main nutrient acquisition strategy under N and P co-limitation. In contrast, the root strategy is the main one when an individual is subject to limitations in N or P in karst ecosystems. Root and mycorrhizal nutrient acquisition strategies are generally mutualistic, mycorrhizal strategy enhances plant nutrient acquisition under N and P co-limitation.

Background Leaves and needles are pivotal plant tissues in regulating carbon input, nutrient uptake, and biogeochemical cycling within ecosystems. However, the ecological strategy of broadleaved and coniferous tree species affecting the endophytic colonization of leaf/needle for enabling a nutrient release of subsequent litter is not fully known. The bacterial community assembly, functions, and interactions (summarized as attributes) inhabiting senescing leaves and needles in eleven common tree species of Central European forests were investigated using next generation sequencing. Results Endophytic bacterial attributes varied significantly among tree species and between tree types (broadleaved and coniferous trees). Deterministic processes (nitrogen (N) related factors) governed the endophytic bacterial community assemblages in broadleaved tree species, which were dominated by ureolytic bacteria that potentially caused the increase in inorganic N. In turn, stochasticity (homogenizing dispersal and dispersal limitation) predominantly controlled the community assembly of bacteria inhabiting in needles. Compared with broadleaved, coniferous trees exhibited both more diverse bacterial taxa enlarging the capacity to cope with changing environmental factors. Conclusions Our results reveal the endophytic colonization patterns that initiate litter decomposition during leaf and needle maturation and demonstrate variations between tree types.

Background Trichomes play a key role in the development of plants and exist in a wide variety of species. Results In this paper, it was reviewed that the structure and morphology characteristics of trichomes, alongside the biological functions and classical regulatory mechanisms of trichome development in plants. The environment factors, hormones, transcription factor, non-coding RNA, etc., play important roles in regulating the initialization, branching, growth, and development of trichomes. In addition, it was further investigated the atypical regulation mechanism in a non-model plant, found that regulating the growth and development of tea ( Camellia sinensis ) trichome is mainly affected by hormones and the novel regulation factors. Conclusions This review further displayed the complex and differential regulatory networks in trichome initiation and development, provided a reference for basic and applied research on trichomes in plants.

Climate change has exacerbated the effects of abiotic stresses on plant growth and productivity. Drought is one of the most important abiotic stress factors that interfere with plant growth and development. Plant selection and breeding as well as genetic engineering methods used to improve crop drought tolerance are expensive and time consuming. Plants use a myriad of adaptative mechanisms to cope with the adverse effects of drought stress including the association with beneficial microorganisms such as plant growth promoting rhizobacteria (PGPR). Inoculation of plant roots with different PGPR species has been shown to promote drought tolerance through a variety of interconnected physiological, biochemical, molecular, nutritional, metabolic, and cellular processes, which include enhanced plant growth, root elongation, phytohormone production or inhibition, and production of volatile organic compounds. Therefore, plant colonization by PGPR is an eco-friendly agricultural method to improve plant growth and productivity. Notably, the processes regulated and enhanced by PGPR can promote plant growth as well as enhance drought tolerance. This review addresses the current knowledge on how drought stress affects plant growth and development and describes how PGPR can trigger plant drought stress responses at the physiological, morphological, and molecular levels. Highlight This review aims to highlight the recent advances in understanding the effects of plant growth-promoting rhizobacteria in enhancing plant growth and drought stress tolerance.

Background Fruits are vital food resources as they are loaded with bioactive compounds varying with different stages of ripening. As the fruit ripens, a dynamic color change is observed from green to yellow to red due to the biosynthesis of pigments like chlorophyll, carotenoids, and anthocyanins. Apart from making the fruit attractive and being a visual indicator of the ripening status, pigments add value to a ripened fruit by making them a source of nutraceuticals and industrial products. As the fruit matures, it undergoes biochemical changes which alter the pigment composition of fruits. Results The synthesis, degradation and retention pathways of fruit pigments are mediated by hormonal, genetic, and environmental factors. Manipulation of the underlying regulatory mechanisms during fruit ripening suggests ways to enhance the desired pigments in fruits by biotechnological interventions. Here we report, in-depth insight into the dynamics of a pigment change in ripening and the regulatory mechanisms in action. Conclusions This review emphasizes the role of pigments as an asset to a ripened fruit as they augment the nutritive value, antioxidant levels and the net carbon gain of fruits; pigments are a source for fruit biofortification have tremendous industrial value along with being a tool to predict the harvest. This report will be of great utility to the harvesters, traders, consumers, and natural product divisions to extract the leading nutraceutical and industrial potential of preferred pigments biosynthesized at different fruit ripening stages.

Research in the past decade has demonstrated that a single reference genome is not representative of a species’ diversity. MaizeGDB introduces a pan-genomic approach to hosting genomic data, leveraging the large number of diverse maize genomes and their associated datasets to quickly and efficiently connect genomes, gene models, expression, epigenome, sequence variation, structural variation, transposable elements, and diversity data across genomes so that researchers can easily track the structural and functional differences of a locus and its orthologs across maize. We believe our framework is unique and provides a template for any genomic database poised to host large-scale pan-genomic data.