Leaf Species Research Articles

Genomic evidence for contrasting patterns of host-associated genetic differentiation across shared host-plant species in leaf- and bud-galling sawflies.

Resource specialization and ecological speciation arising through host-associated genetic differentiation (HAD) are frequently invoked as an explanation for the high diversity of plant-feeding insects and other organisms with a parasitic lifestyle. While genetic studies have demonstrated numerous examples of HAD in insect herbivores, the rarity of comparative studies means that we still lack an understanding of how deterministic HAD is, and whether patterns of host shifts can be predicted over evolutionary timescales. We applied genome-wide single nucleotide polymorphism and mitochondrial DNA sequence data obtained through genome resequencing to define species limits and to compare host-plant use in population samples of leaf- and bud-galling sawflies (Hymenoptera: Tenthredinidae: Nematinae) collected from seven shared willow (Salicaceae: Salix) host species. To infer the repeatability of long-term cophylogenetic patterns, we also contrasted the phylogenies of the two galler groups with each other as well as with the phylogeny of their Salix hosts estimated based on RADseq data. We found clear evidence for host specialization and HAD in both of the focal galler groups, but also that leaf gallers are more specialized to single host species compared with most bud gallers. In contrast to bud gallers, leaf gallers also exhibited statistically significant cophylogenetic signal with their Salix hosts. The observed discordant patterns of resource specialization and host shifts in two related galler groups that have radiated in parallel across a shared resource base indicate a lack of evolutionary repeatability in the focal system, and suggest that short- and long-term host use and ecological diversification in plant-feeding insects are dominated by stochasticity and/or lineage-specific effects.

Deep learning-based segmentation for disease identification

Plant diseases have recently increased and exacerbated due to several factors such as climate change, chemicals’ misuse and pollution. They represent a severe threat for both economy and global food security. Recently, several researches have been proposed for plant disease identification through modern image-based recognition systems based on deep learning. However, several challenges still require further investigation. One is related to the high variety of leaf diseases/ species along with constraints related to the collection and annotation of real-world datasets. Other challenges are related to the study of leaf disease in uncontrolled environment. Compared to major existing researches, we propose in this article a new perspective to handle the problem with two main differences: First, while most approach aims to identify simultaneously a pair of species-disease, we propose to identify diseases independently of leaf species. This helps to recognize new species holding diseases that were previously learnt. Moreover, instead of using the global leaf image, we directly predict disease on the basis of the local disease symptom features. We believe that this may decrease the bias related to common context and/or background and enables to build a more generalised model for disease classification. In particular, we propose an hybrid system that combines strengths of deep learning-based semantic segmentation with classification capabilities to respectively extract infected regions and determine their identity. For that, an extensive experimentation including a comparison of different semantic segmentation and classification CNNs has been conducted on PlantVillage dataset (leaves within homogeneous background) in order to study the extent of use of local disease symptoms features to identify diseases. Specifically, a particular enhancement of disease identification accuracy has been demonstrated in IPM and BING datasets (leaves within uncontrolled background).

黄土高原不同植被带内草地植物叶片解剖性状的变异规律

PDF HTML阅读 XML下载 导出引用 引用提醒 黄土高原不同植被带内草地植物叶片解剖性状的变异规律 DOI: 10.5846/stxb202110072767 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 陕西省高校科协青年人才托举计划项目（20200203）；国家重点研发计划（2017YFA0604803）；陕西省自然科学基础研究计划一般项目（2019JQ-028）；陕西省博士后科研资助项目（2018BSHEDZZ141） Variation in leaf anatomical traits of grassland plants in different vegetation zones on the Loess Plateau Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:叶片作为植物与外界进行物质交换的桥梁，其解剖性状能够相互协调以应对外界环境对植物生长造成的不利影响，从而反映出植物对环境变化所采取的适应策略。通过对黄土高原不同植被带（森林草原带、典型草原带、荒漠草原带）草地群落中常见115种植物（包括单子叶植物，双子叶植物，木本植物和草本植物四种功能型植物）叶片进行取样，并运用石蜡制片技术和光学显微技术获得叶片解剖性状（包括表皮厚度、栅栏组织厚度、海绵组织厚度、叶肉厚度和叶片厚度），旨在研究不同植被带内草地植物叶片解剖性状的变异规律及其与群落内物种相对优势度之间的关系，为黄土高原植被恢复和生态环境改善提供理论依据。结果表明：（1）沿着干旱梯度，从森林草原带、典型草原带到荒漠草原带，除叶肉厚度外，植物各叶片解剖性状值均呈现增大趋势，表明干旱地区叶片的旱生结构特征明显。（2）不同功能型植物叶片解剖性状与环境因子的关系各异。木本植物和草本植物的栅栏组织厚度和栅海比均与降水和土壤养分呈显著负相关关系（P<0.05）。同时，木本植物的叶片厚度与水分呈显著负相关关系（P<0.05），而草本植物表皮厚度仅与土壤养分呈显著负相关关系（P<0.05）。其次，除海绵组织厚度和叶肉厚度外，双子叶植物各解剖性状厚度均与降水和土壤养分呈显著负相关关系（P<0.05），而单子叶植物叶片解剖性状没有明显变化（P>0.05）。（3）在不同植被带中，叶片解剖性状与物种优势度间的关系存在差异。其中，森林草原带中物种优势度与叶肉、叶片厚度呈显著负相关关系（P<0.05），说明薄叶植物具有更强的竞争力；典型草原带中物种优势度与叶片解剖性状没有显著相关性（P>0.05）；荒漠草原带中物种优势度与栅栏组织厚度呈显著正相关关系（P<0.05），说明光合能力强的物种具有高竞争力。 Abstract:As a bridge connecting plants and the external environment, leaves can coordinate each anatomical traits to deal with the adverse effects of extrinsic factors on plant growth. Therefore, variation in leaf anatomical traits reflecting the adaptation strategies of plants to the environmental changes. In this study, the leaves of 115 common plants (including monocotyledonous plants, dicotyledonous plants, woody plants and herbaceous plants four functional types of plants) from different vegetation zones (including forest-steppe, steppe and desert-steppe) on the Loess Plateau were sampled, and the leaf anatomical traits (including epidermal tissue thickness, palisade tissue thickness, sponge tissue thickness, mesophyll tissue thickness and leaf thickness) were measured by using paraffin sectioning technique and optical microscopy technique. We aimed to examine the variation in leaf anatomical traits and their relationships with the each species' relative dominance within communities of different vegetation zones, in order to provide theoretical basis for vegetation restoration and ecological environment improvement on the Loess Plateau. Our results showed that, except mesophyll tissue thickness, other six parameters of anatomical traits increased from forest-steppe to steppe and desert-steppe, indicating that the xerophytic characters of leaves became more obvious in these habitats which had less precipitation. Moreover, the environmental influences on leaf anatomical traits differed among different plant growth and cotyledon types. The palisade tissue thickness and palisade-spongy tissue thickness ratio were significantly negatively correlated with precipitation and soil nutrients for both herbaceous and woody species (P<0.05). However, the epidermis tissue thickness of herbs was only significantly negatively correlated with soil nutrients (P<0.05), and the mesophyll tissue thickness of woody species was significantly negatively correlated with precipitation (P<0.05). For dicotyledons, the thickness parameters of anatomical traits (expect for sponge tissue thickness and mesophyll tissue thickness) were significantly negatively correlated with precipitation and soil nutrients (P<0.05). However, environmental factors didn't exert significant influences on the leaf anatomical traits of monocotyledons (P>0.05). In addition, the relationships between leaf anatomical traits and species' dominance differed among different vegetation zones. Specifically, the species dominance was significantly negatively correlated with mesophyll tissue thickness and leaf thickness in forest-steppe (P<0.05), indicating that these plants with thin-leaves were more competitive than those plants with thick leaves in this zone. In desert-steppe, there was a significantly positive correlation between species dominance and palisade tissue thickness, which suggests that stronger photosynthetic capacity the species had, higher competitiveness they could own (P<0.05). However, no significant correlation between species dominance and leaf anatomical traits was observed in steppe (P>0.05). 参考文献 相似文献 引证文献

A Hybrid Deep Learning Approach to Classify the Plant Leaf Species

A Hybrid Deep Learning Approach to Classify the Plant Leaf Species

Biogeochemical niche conservatism relates to plant species diversification and life form evolution in a subtropical montane evergreen broad-leaved forest.

The evolutionary mechanisms underlying the biogeochemical niche conservatism in forests remain incompletely understood. Here we aimed to determine how the strengths of biogeochemical niche conservatism vary among elements and between life forms. We measured leaf concentrations of basal elements (C, N, P, K, Ca, and Mg) in a wide range of life forms in a subtropical montane evergreen broad-leaved forest. We found that differences in life forms such as evergreen/deciduous woody species and herbaceous/woody species significantly affected leaf elemental composition. The significant phylogenetic signal was present in leaf C, N, K, and Mg concentrations but absent in leaf P and Ca concentrations in all species. These contrasting strengths of biogeochemical niche conservatism were best generated by Ornstein-Uhlenbeck processes toward optima. Woody species were evolutionarily selected to show lower optimal leaf N, P, and K concentrations and higher optimal leaf C, Ca, and Mg concentrations than herbaceous species. The number of optima varied from the least in leaf C concentration to the most in leaf Ca concentration, suggesting the stronger convergent evolution of leaf Ca concentration. The positions of optima toward the tips were more selected in woody species, suggesting the more frequency of species-specific adaptations in woody species. The positions of optima were also selected at the nodes towards the species groupings from certain life forms (e.g., the group of 12 Polypodiales ferns in leaf Ca evolution and the group of three evergreen Theaceae species in leaf P evolution) that were converged to present similar leaf elemental composition. During the evolution of biogeochemical niche, strong correlations were found among leaf C, N, P, and K concentrations and between leaf Ca and Mg concentrations. In conclusion, the strengths of biogeochemical niche conservatism can vary among elements and between life forms due to the different tempo and mode of Ornstein-Uhlenbeck processes.

Warming water and leaf litter quality but not plant origin drive decomposition and fungal diversity in an experiment.

The fungi associated with leaf litter play a key role in decomposition and can be affected both by the warming water and the invasion of non-native species in riparian vegetation. Warming water and invasion of non-native riparian species on stream fungal communities have been studied mainly in temperate ecosystems. We tested the effects of warming water and non-native plant Psidium guajava on leaf litter decomposition, conidia density, species richness and beta diversity of tropical stream fungi. Thus, we carried out an experiment using the current mean temperature of streams from northwestern Paraná in South Brazil (22°C) and two temperatures above the current mean temperature (26°C and 29°C). We also used the leaves of a non-native plant (P.guajava), and two native plants (one of similar nutritional quality, and the other of higher nutritional quality than the non-native species) occurring in Neotropical streams riparian vegetation. Warming water accelerated leaf litter decomposition and reduced conidia density and fungal richness in native and non-native plants. However, species composition and beta diversity were not affected by water temperature. Our study showed that warming affects the fungi of streams, the main microorganisms responsible for decomposition and that the nutritional quality of the leaves may be more important than the origin of riparian plant species. Despite this, further investigations should be conducted on the interaction of P.guajava with the flow of nutrients in these environments and how it can affect other ecosystem processes and the food chain. Efforts to study the effects of water warming and biological invasion on the attributes and distribution of fungi in streams are vital, making them a tool for the conservation of riparian ecosystems.

Leaf and Root Litter Species Identity Influences Bacterial Community Composition in Short-Term Litter Decomposition

Microorganisms play a crucial role in litter decomposition in terrestrial ecosystems. The leaf and fine root litters of Robinia pseudoacacia Linn., Quercus acutissima Carr., Pinus tabulaeformis Carr. and Pinus densiflora Sieb. were analysed using the nylon litter bag method and Illumina MiSeq high-throughput sequencing for the amplification of bacterial 16S rRNA V4–V5. We assessed the effects of leaf and root litter species on the bacterial community after one year’s decomposition. The results showed that (1) the remaining mass of fine root litter was smaller than that of the leaf litter for R. pseudoacacia and Q. acutissima, while the opposite result was found for P. tabulaeformis and P. densiflora. (2) The bacterial community structure in leaf litter was most highly correlated with the initial N content and N:P, while that in fine roots was most highly correlated with the lignin content. (3) The bacterial phyla Bacteroidetes, Acidobacteria and Gemmatimonadetes were significantly affected by litter and species, whereas the relative abundances of Firmicutes and Chloroflexi were only affected by litter tissues. The relative abundances of Acidobacteria, Firmicutes and Chloroflexi in fine root litter were higher than those in leaf litter, while the opposite result was found for Bacteroidetes. The bacterial genera Burkholderia-Paraburkholderia, Sphingomonas and Mucilaginibacter were affected by litter tissues (p &lt; 0.05). The relative abundance of Burkholderia-Paraburkholderia in fine root litter was higher than that in leaf litter, while the opposite result was found for Bradyrhizobium, Sphingomonas and Mucilaginibacter. Pearson’s correlation analysis showed that the relative abundances of the dominant phyla and genera were affected by the initial litter properties, especially for Bacteroides, Acidobacteria, Burkholderia and Sphingomonas. These findings indicate that litter tissues and their interactions with species are more important than the species in shaping the bacterial diversity and community composition, which was affected by the initial chemical properties of the litter.

Patterns of compound-leaf form and deciduous-leaf habit across forests in China: Their association and key climatic factors

Leaf form (compound vs. simple) and habit (evergreen vs. deciduous) are key functional traits of trees to adapt to various climates and are vital in determining plant response to climate change. However, their association and climatic determinants remain uncertain, especially in East Asian forests in the largest monsoon region on earth. To fill these knowledge gaps, we compiled a dataset comprising 42 intact forests and over 2200 angiosperm tree species across China (spanning 30 latitudes and 47 longitudes). The geographical and climatic patterns of leaf form and habit were analyzed. The association between compound leaf and deciduousness was tested for tropical, subtropical and temperate climatic zones. We found that both the percentage of compound leaf (CT%) and deciduous tree species (DT%) increased with latitude and decreased with mean annual precipitation (MAP). For all forests, DT% was negatively related to mean annual temperature (MAT), whereas CT% was not. Nevertheless, both DT% and CT% increased with increasing MAT in the tropics, possibly owing to the high vapor pressure deficits (VPD) and canopy water deficits associated with high temperatures. A positive linear relationship between CT% and DT% was found across all forests and within different climatic zones except for temperate, and the intercept of the regression line was significantly higher in the tropics than in the subtropics. Overall, as supported by principal component analysis, deciduousness was negatively associated with both temperature and precipitation, while CT negatively with precipitation only across zones and positively with temperature in the tropics. Different relationships in different climatic zones suggest potentially different selective forces. Our findings provide novel insights into the linkage between leaf form and habit, as well as how climate shapes the landscape of broadleaf forests, which has important implications regarding the response of forest composition to climate change.

Leaf species and disease classification using multiscale parallel deep CNN architecture

Leaf species and disease classification using multiscale parallel deep CNN architecture

Optical Sensing of Chlorophyll(in) With Dual-Spectrum Si LEDs in SOI-CMOS Technology

Small and low-cost chlorophyll sensors are popular in agricultural sector and food-quality control.Combining such sensors with silicon CMOS electronics is challenged by the absence of silicon-integrated light-sources.We experimentally achieve optical absorption sensing of chlorophyll based pigments with silicon (Si) micro light-emitting diodes (LED) as light-source, fabricated in a standard SOI-CMOS technology.By driving a Si LED in both forward and avalanche modes of operation,we steer its electroluminescentspectrum between visible (400–900 nm) and near-infrared (~1120 nm). For detection of chlorophyll in solution phase, the dualspectrum light from the LED propagates vertically through glycerol micro-droplets containing sodium copper chlorophyllin at varying relative concentrations. The transmitted light is detected via an off-chip Si photodiode. The visible to near-infrared color ratio (COR) of the photocurrent yields the effective absorption coefficient. We introduce the LED-specificmolar absorption coefficient as ametric to compute the absolute pigment concentration (~0.019 ± 0.006 mol L <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> ) and validate the results by measurements with a hybrid spectrophotometer. With the same sensor, we also show noninvasive monitoring of chlorophyll in plant leaves. COR sensitivities <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 3.9 \times 10^{4}$ </tex-math></inline-formula> mol <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> L and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 5.3 \times 10^{4}$ </tex-math></inline-formula> mol <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> L are obtained for two leaf species, where light from the LED propagates diffusely through the thickness of the leaf prior to detection by the photodiode. Our work demonstrates the feasibility of realizing fully CMOS-integrated optical sensors for biochemical analyses in food sector and plant/human health.

Resource preference of two stream detritivores in the laboratory largely differs from the supply of detritus below eucalypt plantations

Detritivores are pivotal in forest streams as they process detritus and promote secondary production. Many studies have addressed the preference of freshwater detritivores towards materials of differing quality. Nevertheless, few studies compare the resource preferences in the laboratory with the availability in the field. In the present study, feeding preferences of two stream detritivores (the caddisfly Sericostoma pyrenaicum and the amphipod Echinogammarus tarragonensis), over three native leaf species (alder, chestnut and oak) and an exotic species (eucalypt) were quantified in the laboratory. Preference for eucalypt leaves conditioned for 1, 2 and 3 weeks was also described. We then contrasted the preference patterns in the laboratory feeding experiments with a 15-month-long benthic standing stock time series of a stream below a native deciduous forest and another below a eucalypt plantation. Both detritivores preferred consuming alder leaves and more conditioned eucalypt leaves, although the amphipod was more selective than the caddisfly. The consumption preference in the laboratory was unmatched by the availability in the field, especially under eucalypt plantations and for the amphipod. Our results show that the strength of the preference for high-quality resources can differ among different taxa, which can modulate their response to land use changes.

Potential of nutrient input and released from decomposing leaf litter of three dominant tree species found in a subtropical semi evergreen riparian forest of Dikhu river, Nagaland, India

Studies on nutrient dynamic in riparian ecosystem is very less compared with the upland forest ecosystem.The main aim of the study was to compare the rate of nutrient input and release through decompositionfrom leaf litterfall of three dominant tree species, i.e., Melia azedarach L., Terminalia chebula Retz. and Duabangagrandiflora (DC.) Walp. found in a subtropical semi evergreen riparian forest of Dikhu river, Nagaland,India. The concentration of the initial composition of plant nutrients viz., C, N, P and K was analaysed fromthe grounded air-dried leaf litter and nutrient released through decomposition from the leaf litter wasestimated by using litter trap approach following standard methods. The initial concentration of nutrientsin all the 3 leaf species followed the trend as (1.12%) N &gt; (0.21%) K &gt; (0.098%) P in M. azedarach, (1.40%) N&gt; (0.17%) K &gt; (0.086%) P in T. chebula and (1.98%) N &gt; (0.22%) K &gt; (0.074%) P in D. grandiflora. Carboncontent was highest in the entire 3 leaf litter component and followed the pattern as D. grandiflora (65.50%)&gt;T. chebula (60.50%)&gt;M. azedarach (51.80%). In M. azedarach and D. grandiflora, N is accumulated during theinitial phase of decomposition and released in the later phase. However, in T. chebula, N is released in theinitial phase and immobilization in the later phase. In all the 3 species, the released of C follows a similarpattern by characterizing early immobilization in the first 9 months (0 to 243 days). A rapid rate of Preleased was observed at the early decomposition period. There observed a faster decrease of K (%) from allthe decomposing leaf litter. In conclusion, it was found that differences in chemical composition and nutrientsrelease dynamics during decomposition of leaf litter was observed in all the 3 tree species.

Carbon Regulating Services of A 30-year-old Reclaimed Limestone Mine Area in Foothills of Himalaya

The study aims to assess various carbon regulating services of a limestone mine site, reclaimed 30 years back, compared to its adjoining natural forest. The natural forest is dominated by broad leaf species ( Quercus leucotricophora ) whereas, the reclaimed sites have Cupressus torulosa as the dominant species. Though there was no significant difference in the number of species of various life forms (trees, shrubs, herbs and grasses), total basal cover (TBC) estimated for the natural forest (2513.36cm 2 /100m 2 ) was much higher compared to the reclaimed site (584.30 to 997.07 cm 2 /100m 2 ). The difference is much higher in TBC of trees compared to shrubs. Annual litter production was also higher in the natural forest. Microbial activity in the top soil layer was found to have increased substantially in the reclaimed mine site. Soil respiration rate and soil microbial biomass in the reclaimed mine site was on a par with that of natural forest. It indicates a significant level of organic matter and detritus availability in the reclaimed sites' top soils since the soil's degradable organic carbon is the main fuel responsible for the CO emission during soil 2 respiration. Though the carbon assimilation rate recorded in the vegetation of the reclaimed area is on a par with that of vegetation of natural forest at the species level, at the community level, the reclaimed site may have lower assimilation owing to lower TBC. Therefore, the difference in vegetation structure and composition in the reclaimed site compared to the natural forest might significantly impact the overall carbon regulating services in the study area.

Klasifikasi Citra Daun Herbal Dengan Menggunakan Backpropagation Neural Networks Berdasarkan Ekstraksi Ciri Bentuk

Since ancient times until now herbal plants have been used for treatment and have been applied in the world of health to this day. All parts of the plant can be used as medicine, one of which is the leaves. However, there are still many people who are not familiar with the medicinal leaves. This is because the leaves at first glance look almost the same, making it difficult to tell them apart. Actually, if you look closely, the leaves have characteristics that can be distinguished from one leaf to another. The purpose of this study is to classify images of herbal leaf species using the Backpropagation Neural Network (BNN) algorithm with shape feature extraction utilizing metric and eccentricity parameters. BNN is a type of supervised learning algorithm that consists of several layers and uses an error output as a modifier of the weight value backwards. In this study, the extraction of shape features that become input for the BNN algorithm will go through morphological operations to improve the segmentation results so that the classification results are more optimal. The test results show an accuracy of 88.75%, this shows the developed model can classify herbal leaves well

Assessing the impacts of urbanization on stream ecosystem functioning through investigating litter decomposition and nutrient uptake in a forest and a hyper-eutrophic urban stream

Rapid urbanization significantly affects freshwater systems by interfering with important ecological functions. The responses of different ecosystem functions in urban streams and their potential ecological effects remain largely unknown, impeding their management and restoration in many cases. In this study, we simultaneously assessed two important ecosystem functions, litter decomposition and nutrient uptake, and investigated the associated microbial and benthic macroinvertebrate communities in two subtropical streams (i.e., a forest headwater stream as a reference and an urban stream that was hyper-eutrophic). Litter decomposition was estimated using litter bags with two mesh sizes (i.e., 50 μm and 2 mm) and two leaf species with different qualities (i.e., Alangium chinense and Machilus leptophylla), with a total of 96 litter bags. Nitrogen (N) and phosphorus (P) uptake rates were measured in situ based on the spiraling model. We found that the decomposition rate of A.chinense was approximately seven times that of M. leptophylla in both streams. Moreover, in the urban stream, the litter decomposition rate (0.004 day−1) was one-third that of the forest stream (0.013 day−1), regardless of the litter species. Macroinvertebrates strongly contributed to litter decomposition in the forest stream, where decomposition rates were 1.8-fold higher in the coarse mesh compared to the fine mesh bags, while they had a negligible role in the urban stream (no significant difference between the two mesh bags). P uptake was higher (85-fold) and N uptake was lower (0.13-fold) in the urban compared to forest stream. Litter decomposition and nutrient uptake exhibit decoupled response. These findings show that litter decomposition by kcoarse/kfine metrics and the uptake of N and P are complementary and should be considered in the management and restoration of urban stream ecosystems.

Improved Protocol of RNA Isolation for Transcriptome Analysis of Poaceae Plants

The existence of metabolites that interfere with isolation procedures and downstream applications makes plant RNA extraction difficult. The current research used a standardized RNA extraction protocol from maize (Zea mays L.). We developed a protocol for extracting pure RNA from plant tissues using both extraction buffer and the TRIzol reagent, and show that this RNA extraction method works not only at Low temperatures but also at room temperatures, making it the easiest and most efficient method for extracting pure and undegraded RNA directly from tropical plants in the field. RNA isolation methods based on our modified protocol yielded good results in maize leaf, seed, flowers and other grass species. The isolated RNA was found to be suitable for both PCR and RT-PCR amplification and transcriptome analysis. The method is repeatable and can be used to isolate high-quality RNA and conduct gene expression studies. RNA extraction paves the way for deciphering the complex regulatory network involved in multiple stress responses by studying gene-environment interactions at the transcriptome level.

Techniques for Leaf Classification

Various methods for grouping of plants in view of their leaves have been created throughout the course of recent years. While every one of those procedures have been independently executed and assessed, yet there have been not many investigations which have made an immediate examination between the different methods. Plant acknowledgment frameworks that created by PC vision analysts, help botanists in quicker acknowledgment what's more location of obscure plant species. As of not long ago, different studies zeroed in on the cycle or calculations that boost utilization of plant datasets for plants forecast displaying, yet this strategy relies upon leaf attributes which can be change with plant information and different component extraction procedures. Methodologies for leaf species recognizable proof from white foundation utilizing cell phones. Varieties of models over the highlights like customary shape, surface, shading and venation separated from the other small elements of consistency of edge designs, leaf tip, edge and other factual highlights are investigated for productive leaf characterization.

A Preliminary Investigation on the Use of Warm-Season Grasses as Vegetative Environmental Buffers to Capture Particulate Matter from Manure Pit Exhaust Fans Associated with a Swine Finishing Facility

Airborne Particulate Matter (PM) released through exhaust fans from livestock barns can be environmentally objectionable resulting in enhanced odors and the release ammonia and harmful microbes. While large trees and woody shrubs have been recommended as Vegetative Environmental Buffers (VEB) for capturing PM from exhaust from off the ground ventilation fans in livestock barns, grasses due to their smaller vegetative size may be more suitable for capturing PM from exhaust from ground level manure pit fans often unique to swine barns. Since there is limited information on the use of grasses as VEB in animal barns, we developed this preliminary investigation to determine if warm season grasses (Panicum virgatum L. ‘Northwind’, Miscanthus sinensis Anderss. ‘Zebrinus’, and Andropogon gerardii Vitman ‘Blackhawk’) could capture air borne particulates (PM10 and PM2.5) from ground level manure pit exhaust fans located at a swine finishing facility near Lancaster, Pennsylvania (USA). We observed that all three grass species accumulated PM on their leaves with the more pubescent leafed species (Miscanthus and Andropogon) tending to capture more PM on their leaves than the non-pubescent leafed Panicum. Additional research evaluating a larger number of plants and species is needed for more accurate interpretation of results and to further refine and improve the conclusions and recommendations on the use of warm season grasses as VEB for PM in these facilities.

天坑森林植物群落叶功能性状、物种多样性和功能多样性特征

PDF HTML阅读 XML下载 导出引用 引用提醒 天坑森林植物群落叶功能性状、物种多样性和功能多样性特征 DOI: 10.5846/stxb202110273025 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（31960047）；珍稀濒危动植物生态与环境保护教育部重点实验室研究基金（ERESEP2019Z04）；广西重点研发计划项目（桂科AB21220057）；广西漓江流域景观资源保育与可持续利用重点实验室研究基金（LRCSU21Z0101） Leaf functional traits, species diversity and functional diversity of plant community in Tiankeng forests Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以天坑内部-边缘-外部森林植物群落为研究对象，通过调查植物的群落结构、叶功能性状，探究天坑内外森林植物群落叶功能性状、物种多样性和功能多样性变化特征及其内在关联，为深入了解负地形森林生态系统的功能和恢复退化喀斯特地区的植被提供一定参考。研究结果如下：（1）比叶面积（198.75 cm2/g））、叶面积（42.70 cm2）、叶磷含量（1.70 g/kg）和叶钾含量（10.27 g/kg）在天坑内部最高，叶组织密度（0.32 g/cm3）和叶干物质含量（0.41 g/g）在天坑外部最高，天坑内外森林均易受到磷限制，表明随天坑内部-边缘-外部生境变化，植物对环境的适应机制和生存策略发生了部分调整，物种的防御策略增强，生长投入策略减弱。（2） Shannon-Wiener指数（2.82）、Simpson指数（0.92）和Pielou's均匀度指数（0.87）均以天坑外部最高，功能丰富度（1.05）、功能离散度（1.88）和Rao's二次熵（4.52）以天坑内部最高，表明随天坑内部-边缘-外部生境的变化，植物功能性状的差异减少，物种分布及其功能性状分布总体上更为均匀、物种数量增多。（3）物种多样性指数之间、功能多样性指数之间存在较强的相关性，表明物种多样性指数之间、功能多样性指数之间存在不同的制约关系。（4）叶功能性状与物种多样性、功能多样性的相关性强，物种多样性和功能多样性之间相关性较弱，表明叶性状对生态学过程的变化较为敏感，叶功能性状与物种多样性之间存在较强的耦合关系。 Abstract:To explore leaf functional traits, species diversity, and functional diversity characteristics and correlation of plant community in Tiankeng forests will help to build the context of leaf traits, species diversity, and functional diversity research context, and further understand the process and functions of the ecological system in the negative terrain forest, and provide a scientific basis for restoration and reconstruction of the vegetation in degraded karst areas. This paper takes the woody plant community in three habitats (the inside of Tiankeng, the fringe of Tiankeng, and the outside of Tiankeng) of Dashiwei Tiankeng Group as the object, to study the leaf functional traits, species diversity, functional diversity characteristics and their interactions, through community investigation and leaf functional traits measurement. The results are as follows:(1) woody plant grown in the inside of Tiankeng shows the highest specific leaf area (SLA:198.75 cm2/g), leaf area (LA:42.70 cm2), leaf phosphorus content (LPC:1.70 g/kg) and leaf potassium content (LKC:10.27 g/kg), in the outer of Tiankeng presents the highest leaf tissue density (LTD:0.32 g/cm3) and leaf dry matter content (LDMC:0.41 g/g), and the growth of woody plant is limited by P in Tiankeng forests and nearby karst forests. With the variation of habitats from the inner to the outer of Tiankeng, partial adjustments are made in the adaption mechanism and survival strategy of the woody plant. A quick defense strategy on investment for the species increases, while a slow growth strategy on investment of species is weak. (2) Shannon-Wiener index (2.82), Simpson index (0.92) and Pielou's evenness index (0.87) in the outside of Tiankeng are the highest, and the functional richness index (1.05), function dispersion index (1.88) and Rao's quadratic entropy index (4.52) in the inside of Tiankeng are the highest. With the variation in the inner-edge-outer habitats of Tiankeng community, the differences in plant functional traits reduce, the range of species distribution and functional traits are steady, and the individual of species increases. (3) There is significantly correlated to each species diversity and functional diversity, indicating that there are different restrictive relationships between species diversity and functional diversity. (4) The leaf functional traits are significantly correlated with species diversity and functional diversity, and the correlation between species diversity and functional diversity is weak, indicating that leaf traits are more sensitive to variation of ecological processes and there is a strong coupling relationship between leaf functional traits and species diversity. 参考文献 相似文献 引证文献

Stomatal size and density trade-off varies with leaf phenology and species shade tolerance in a South Asian moist tropical forest

The density and guard cell length of stomata regulate the physiological processes in plants. Yet, the variation of stomatal characteristics among different functional groups of trees is not been well understood. Particularly, a comprehensive understanding of stomatal behaviour in Bangladeshi moist forest trees is lacking. The study investigated how abaxial stomatal density (SD) and guard cell length (GCL) vary among tree functional types and leaf phenological groups in a moist tropical forest of Bangladesh. Cluster dendrogram revealed three groups of species based on SD and GCL. The independent sample t -test showed that there was a significant difference in SD between evergreen and deciduous tree species (t =4.18, P <0.001) but no significant difference in GCL between the two phenological groups. ANOVA revealed no significant difference in SD among the light demanding, intermediate shade tolerant and shade tolerant species (F =0.76, P =0.47). However, GCL significantly differed among the three functional groups (F =3.3, P <0.05). Maximum theoretical stomatal conductance (g max ) varied between evergreen and deciduous species but did not vary with species shade tolerance. In general, there was a significant trade-off between SD and GCL. However, the inverse relationship was stronger in deciduous and shade tolerant species than in evergreen and shade intolerant species. Leaf dry matter content was positively related with SD and negatively related with GCL. Specific leaf area and leaf thickness were not related to the stomatal traits. Our analyses suggest that leaf phenology and species shade tolerance need to be considered while estimating gas exchange through the stomata in tropical moist forests.