Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old A...Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old Arbor Acres broilers were supplemented with a basal diet with 20 mg bacitracin/kg,50 mg BLFs/kg,or 250 mg BLFs/kg or without additions.Data showed that the dietary BLFs significantly(P<0.05)changed growth performance and the texture profile.In particular,BLFs increased birds’average daily gain and average daily feed intake,decreased the feed:gain ratio and mortality rate,improved elasticity of breast meat,enhanced the gumminess of breast and leg meat,and decreased the hardness of breast meat.Moreover,a significant(P<0.05)increase in redness(a*)and chroma(c*)of breast meat and c*and water-holding capacity of leg meat was found in BLF-supplemented broilers compared with control broilers.In addition,BLFs supplementation significantly decreased(P<0.05)theβ-sheet ratio and serum malondialdehyde and increased theβ-turn ratio of protein secondary structure,superoxide dismutase,and glutathione peroxidase of breast meat and total antioxidant capacity and catalase of serum.Based on the analysis of untargeted metabolome,BLFs treatment considerably altered 14 metabolites of the breast meat,including flavonoids,amino acids,and organic acids,as well as phenolic and aromatic compounds.Conclusions Dietary BLFs supplementation could play a beneficial role in improving meat quality and sensory color in the poultry industry by changing protein secondary structures and modulating metabolites.展开更多
One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on a...One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on achieving high photosynthetic efficiency traits in order to enhance the yield.Leaf shape is a significant agronomic trait of upland cotton that affects plant and canopy architecture,yield,and other production attributes.The major leaf shape types,including normal,sub-okra,okra,and super-okra,with varying levels of lobe severity,are controlled by a multiple allelic series of the D-genome locus L-D_(1).To analyze the effects of L-D_(1)alleles on leaf morphology,photosynthetic related traits and yield of cotton,two sets of near isogenic lines(NILs)with different alleles were constructed in Lumianyan 22(LMY22)and Lumianyan 28(LMY28)backgrounds.The analysis of morphological parameters and the results of virus-induced gene silencing(VIGS)showed that the regulation of leaf shape by L-D_(1)alleles was similar to a gene-dosage effect.Compared with the normal leaf,deeper lobes of the sub-okra leaf improved plant canopy structure by decreasing the leaf area index(LAI)and increasing the light transmittance rate(LTR),and the mid-range LAI of sub-okra leaf also guaranteed the accumulation of cotton biomass.Although the chlorophyll content(SPAD)of sub-okra leaf was lower than those of the other two leaf shapes,the net photosynthetic rate(Pn)of sub-okra leaf was higher than those of okra leaf and normal leaf at most stages.Thus,the improvements in canopy structure,as well as photosynthetic and physiological characteristics,contributed to optimizing the light environment,thereby increasing the total biomass and yield in the lines with a sub-okra leaf shape.Our results suggest that the sub-okra leaf may have practical application in cultivating varieties,and could enhance sustainable and profitable cotton production.展开更多
The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscop...The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscope. Results showed that all leaves consisted of epidermis, chlorenchyma, aquiferous tissue and vascular bundles. The leaves had the xeromorphic characteristics, including thickened epidermal cell wall, thickened cuticle, sunken stomata and well-developed aquiferous tissue. With the exception of thus, there were remarkable differences in leaf structure among the six species. The chlorenchyma cells were similar to palisade tissues in Aloe arborescens Mill. and A. mutabilis Pillans, but isodiametric in A. vera L., A. vera L. var. chinensis Berg., A. saponaria Hawer and A. greenii Bali. A. arborescens, A. mutabilis, A. very and A. vera var. chinensis included large parenchymatous cells at the vascular bundles, whereas no such cells were observed at the vascular bundles of A. saponaria and A. greenii. In A. arborescens, A. mutabilis and A. vera, the aquiferous tissue sheaths were present and composed of a layer of small parenchymatous cells without chloroplasts around the aquiferous tissue. While there were no aquiferous tissue sheaths in A. vera var. chinensis, A. saponaria and A. greenii. The HPLC revealed that the content of aloin was high in A. arborescens, low in A. vera, and very low in A. saponaria among the six species. The fluorescent microscopy showed that the yellow-green globule only appeared in the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath, but not in the chlorenchyma and aquiferous tissue. Consequently, the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath were the storage location of aloin. They were positively correlated with the content of aloin.展开更多
Plants usually suffer drought stress during their growth process. As the photosynthetic activity center of plants, the leaf is the most sensitive organ under drought stress. In order to support the research on drought...Plants usually suffer drought stress during their growth process. As the photosynthetic activity center of plants, the leaf is the most sensitive organ under drought stress. In order to support the research on drought resistance of higher plants, this study reviewed the adaptation response and damage performance of epidermal structure, palisade tissue and spongy tissue, thickness, veins and stomata of plant leaves under drought stress.展开更多
[ Objective] Correlation of microstructure of leaf sheath epidermis and nutrient composition of palm plants with the damage degree of red palm fiber elephant in four kinds of plants in Nanning were analyzed in order t...[ Objective] Correlation of microstructure of leaf sheath epidermis and nutrient composition of palm plants with the damage degree of red palm fiber elephant in four kinds of plants in Nanning were analyzed in order to control the occurrence and damage of this insect in Nanning. [Method] Taken 4 kinds of Palmae plants in Nanning including Ravenea fivulafis, Washingtonia filifera, Phoenix canafiensis, Roystonea regia (HBK.)O. F. Cook as materials, damage situation of the red palm fiber elephant was investigated, microstructure of leaf sheath epidermis and nutrient composition of palm plants were analyzed and determined. [ Result] The results showed that there was direct correlation between the microstructure of leaf sheath epidermis and nutrient composition with the physical resistance of palm plant against red palm fiber elephant. The extend of damage from red palm fiber elephant had negatively relation with the thickness of corneum and leaf epidermis. The damage degree caused by red palm fiber elephant increased with the content of crude protein, crude ash and nitrogen free extract increasing, also increased with the content of rude fiber decreasing. [Condusion] The damage degree of red palm fiber elephant had a relationship with microstructure of leaf sheath epidermis and nutrient composition of palm plants.展开更多
[Objective] This study aimed to investigate the effects of PP333 and ex- ogenous ABA on the growth and development of Armeniaca vulgaris 'Luntaibaixing' so as to provide a theoretical basis for the growth regulation...[Objective] This study aimed to investigate the effects of PP333 and ex- ogenous ABA on the growth and development of Armeniaca vulgaris 'Luntaibaixing' so as to provide a theoretical basis for the growth regulation of Luntaibaixing in cultivation and management. [Method} Different concentrations of PP333 and ABA were sprayed to Luntaibaixing during the rapid growth period of fresh treetops. The technology of paraffin section was used to measure the thickness of leaf, upper epidermis, lower epidermis, palisade tissue and sponge tissue. The thickness ratio of palisade tissue to sponge tissue, tightness degree of leaf tissue structure (CTR) and loose degree of leaf tissue structure (SR) were calculated and the differences in leaf tissue structure were analyzed. [Result] The thickness of leaf and palisade tissue both increased significantly after treated by PP333. At the treatment concen- tration of 1 000 mg/L, the thickness ratio of palisade tissue to sponge tissue and the value of CTR were highest, while the thickness of sponge tissue and the value of SR were lowest. The thickness of leaf and palisade tissue also increased after treated by ABA, and it increased most greatly at the ABA concentration of 60 mg/L compared with CK. At the treatment concentration of 60 rag/L, the thickness ratio of palisade tissue to sponge tissue and the value of CTR were the highest, while the thickness of sponge tissue and the value of SR were the lowest. [Conclusion] ABA and PP333 treatment increased the leaf thickness, palisade tissue thickness, pal- isade tissue to sponge tissue thickness ratio and CRT value, but reduced the sponge tissue thickness and SR value of Luntaibaixing.展开更多
[Objective] This study aimed to investigate the leaf anatomical structures of P. tunicoides populations under water-limited conditions. [Method] 2-year-old seedlings of herbaceous perennial P. tunicoides that was intr...[Objective] This study aimed to investigate the leaf anatomical structures of P. tunicoides populations under water-limited conditions. [Method] 2-year-old seedlings of herbaceous perennial P. tunicoides that was introduced into the experi- mental field were selected as the research objects. Under the well-watered and wa- ter-limited conditions, we conducted the comparative observation of leaf anatomical structure and stomatal characteristics of two populations by using paraffin slice method and imprinting method. [Result] The result showed that the upper cuticle of P. tunicoides leaves were thickened, the palisade tissue/spongy tissue ratio, vascular bundle diameter and number of xylem vessels in main vein had increased, the stomatal opening became smaller and the stomatal density had increased in winter- spring drought period under water-limited conditions. The plasticity of above traits could be regarded as the important indicators for detecting the responses of P. tunicoides populations to water-limited conditions. Meanwhile, variation amplitudes of these indicators were different among populations. Leaf anatomical structure and stomatal characteristics in Lijiang Axi population under water-limited conditions varied significantly, which might cause the stronger adaptability of this population to drought conditions. [Conclusion] This research provided a reference for the selection of drought-resistant P. tunicoides germplasm and exploration of the adaptive differentia- tion of P. tunicoides populations under natural drought conditions.展开更多
The leaf development of Podocarpus macrophyllus var.maki Endl.started from the leaf primordium formed by the cell division in shoot apical meristem.During the leaf development,three resin canals from the inferior part...The leaf development of Podocarpus macrophyllus var.maki Endl.started from the leaf primordium formed by the cell division in shoot apical meristem.During the leaf development,three resin canals from the inferior part of vascular bundles firstly began to differentiate,then protoxylem in vascular bundles differentiated from adaxial side to abaxial side.Meanwhile,a layer of parenchyma cells from the inferior part of protoderm developed into the sclerenchyma,which played an important role in supporting young leaves.When xylem became mature basically,transfusion tissue,phloem and accessory transfusion tissue began to differentiate,so mesophyll tissue finally differentiated into developmental palisade cells and sponge cells.The thicker cuticle was formed in the lateral side of epidermal cells at the same time of differentiation and development for the inner structure of leaves.Therefore,the developmental palisade cells and the cuticle in the leaf structure of Podocarpus macrophyllus var.maki Endl.is greatly significant for photosynthesis and transpiration when it grows in arid and cold regions.展开更多
Leaf pigments are critical indicators of plant photosynthesis,stress,and physiological conditions.Inversion of radiative transfer models(RTMs)is a promising method for robustly retrieving leaf biochem-ical traits from...Leaf pigments are critical indicators of plant photosynthesis,stress,and physiological conditions.Inversion of radiative transfer models(RTMs)is a promising method for robustly retrieving leaf biochem-ical traits from canopy observations,and adding prior information has been effective in alleviating the“ill-posed”problem,a major challenge in model inversion.Canopy structure parameters,such as leaf area index(LAI)and average leaf inclination angle(ALA),can serve as prior information for leaf pigment retrie-val.Using canopy spectra simulated from the PROSAIL model,we estimated the effects of uncertainty in LAI and ALA used as prior information for lookup table-based inversions of leaf chlorophyll(C _(ab))and car-otenoid(C_(ar)).The retrieval accuracies of the two pigments were increased by use of the priors of LAI(RMSE of C_(ab) from 7.67 to 6.32μg cm^(-2),C_(ar) from 2.41 to 2.28μg cm^(-2))and ALA(RMSE of C_(ab) from 7.67 to 5.72μg cm^(-2),C_(ar) from 2.41 to 2.23μg cm^(-2)).However,this improvement deteriorated with an increase of additive and multiplicative uncertainties,and when 40% and 20% noise was added to LAI and ALA respectively,these priors ceased to increase retrieval accuracy.Validation using an experimental winter wheat dataset also showed that compared with C_(ar),the estimation accuracy of C_(ab) increased more or deteriorated less with uncertainty in prior canopy structure.This study demonstrates possible limita-tions of using prior information in RTM inversions for retrieval of leaf biochemistry,when large uncer-tainties are present.展开更多
This paper focused on the influence of the shape and size of threshing frames as well as the grades of tobacco leaves on the structure of threshed leaves.The testing tobacco leaves all came from the hilly ecological r...This paper focused on the influence of the shape and size of threshing frames as well as the grades of tobacco leaves on the structure of threshed leaves.The testing tobacco leaves all came from the hilly ecological region of Nanling and belonged to burnt sweet,alcoholic sweet and scent category.The comprehensive evaluating value S was taken as the test index.Results showed that,without considering the influence of tobacco grade on leaf structure,the shapes of first-stage thresher five-link frames were all hexagons,and the combination with the sizes of 3.5,3.0,3.5,3.0,3.0 inches had the highest evaluating value S of 2.49.For tobacco grade C2FH,the shapes of first-stage thresher five-link frames were also hexagons,and the evaluating value S reached the highest value of 3.40 with sizes of 3.5,3.0,3.5,3.0,3.0 inches.Comprehensive analysis showed that:3.0 inch frame performed better in controlling the percentage of large-sized strips than 3.5 inch frame did;rhombic frames were better than hexagon frames in reducing the breakage rate of tobacco leaves;different shapes or sizes of nonadjacent two-link frames can help to improve the threshing quality.展开更多
[Objective] This study was performed to explore the effect of different concentrations of PP333 on leaf tissue structure of Korla fragrant pear and to lay the foundation for the cultivation and regulation of Korla fra...[Objective] This study was performed to explore the effect of different concentrations of PP333 on leaf tissue structure of Korla fragrant pear and to lay the foundation for the cultivation and regulation of Korla fragrant pear. [Method] The leaf tissues treated with different concentrations of PP333 were dehydrated with al- cohol, embedded in paraffin and sliced into 10-μm slices. The thicknesses of leaf blade, upper epidermis, lower epidermis, palisade tissue and sponge tissue were measured, and the ratio of palisade to spongy layer thickness, cell tightness (CT) and cell looseness (CL) were calculated. [Result] The thickness of leaf blade, the ratio of palisade to sponge layer thickness and the thickness of palisade layer were all significantly increased after treatment with PP333. Treatment with 2 500 mg/L PP333 showed no obvious effect on the thickness of leaf epidermis, but increased the thicknesses of leaf blade and palisade tissue. Leaf CL was the highest in the treatment of 1 500 mg/L PP333. [Conclusion] PP333 can increase the leaf thickness, palisade tissue thickness and CT, reduce spongy tissue thickness and CL of Korla fragrant pear. Additionally, 1 500 mg/L was the optimal concentration for the application of PP333 to improve the cold resistance of Koda fragrant pear.展开更多
[Objectives]This study was conducted to investigate the response of Gardenia to purple soil drought stress,hoping to provide a reference for the selection of plants for vegetation restoration in purple soil regions.[M...[Objectives]This study was conducted to investigate the response of Gardenia to purple soil drought stress,hoping to provide a reference for the selection of plants for vegetation restoration in purple soil regions.[Methods]The pot-weighing water control method was used to apply different degrees of drought stress to Gardenia seedlings in purple soil,and the effects of drought stress on the electrical conductivity,chlorophyll content,leaf morphology and structure of Gardenia leaves were explored.[Results]The leaf electrical conductivity increased with the increase of drought stress intensity,and the leaf electrical conductivity under severe drought stress increased by 59.93%compared with the control;the chlorophyll content of Gardenia showed a single-peak changing trend that increased and then decreased with the development of drought stress,and it was the highest in each stress stage under severe drought stress;the leaf thickness,palisade tissue thickness and sponge tissue thickness of Gardenia were reduced with the stress degree increasing,and showed the largest decreases under severe stress;the stomatal length,stomatal width and stomatal opening of Gardenia gradually decreased with the increase of stress,while the stomatal density gradually increased.[Conclusions]This study provides a technical and resource basis for vegetation restoration in purple soil.展开更多
Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurr...Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurring leaf-color rice mutant, Baihuaidao 7, was analyzed. Mutant plants typically exhibited a green-white-green leaf-color progression, but this phenotype was only expressed in the presence of a stress signal induced by mechanical scarification such as transplantation. Prior to the appearance of white ~eaves, mutant plant growth, leaf color, chlorophyll content, and chloroplast ultrastructure appeared to be identical to those of the wild type. After the changeover to white leaf color, an examination of the mutated leaves revealed a decrease in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoid content, a reduction in the number of chloroplast grana lamella and grana, and a gradual degradation of the thylakoid lamellas. At maturity, the mutant plant was etiolated and dwarfed compared with wild-type plants. Genetic analysis indicated that the leaf mutant character is controlled by a recessive nuclear gene. Genetic mapping of the mutant gene was performed using an F2 population derived from a Baihuaidao 7 ~ Jiangxi 1587 cross. The mutant gene was mapped to rice chromosome 11, positioned between InDel markers L59.2-7 and L64.8-11, which are separated by approximately 740.5 kb. The mutant gene is believed to be a new leaf-color mutant gene in rice, and is tentatively designated as gwgl.展开更多
Leaf economics spectrum(LES)describes the fundamental trade-offs between leaf structural,chemical,and physiological investments.Generally,structurally robust thick leaves with high leaf dry mass per unit area(LMA)exhi...Leaf economics spectrum(LES)describes the fundamental trade-offs between leaf structural,chemical,and physiological investments.Generally,structurally robust thick leaves with high leaf dry mass per unit area(LMA)exhibit lower photosynthetic capacity per dry mass(Amass).Paradoxically,“soft and thinleaved”mosses and spikemosses have very low Amass,but due to minute-size foliage elements,their LMA and its components,leaf thickness(LT)and density(LD),have not been systematically estimated.Here,we characterized LES and associated traits in cryptogams in unprecedented details,covering five evolutionarily different lineages.We found that mosses and spikemosses had the lowest LMA and LT values ever measured for terrestrial plants.Across a broad range of species from different lineages,Amass and LD were negatively correlated.In contrast,Amass was only related to LMA when LMA was greater than 14 g cm^(-2).In fact,low Amass reflected high LD and cell wall thickness in the studied cryptogams.We conclude that evolutionarily old plant lineages attained poorly differentiated,ultrathin mesophyll by increasing LD.Across plant lineages,LD,not LMA,is the trait that represents the trade-off between leaf robustness and physiology in the LES.展开更多
Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from ima...Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from image texture and structural information. The difficulties in disease feature extraction in complex backgrounds slow the related research progress. To address the problems, this paper proposes an improved multi-scale inverse bottleneck residual network model based on a triplet parallel attention mechanism, which is built upon ResNet-50, while improving and combining the inception module and ResNext inverse bottleneck blocks, to recognize seven types of apple leaf(including six diseases of alternaria leaf spot, brown spot, grey spot, mosaic, rust, scab, and one healthy). First, the 3×3 convolutions in some of the residual modules are replaced by multi-scale residual convolutions, the convolution kernels of different sizes contained in each branch of the multi-scale convolution are applied to extract feature maps of different sizes, and the outputs of these branches are multi-scale fused by summing to enrich the output features of the images. Second, the global layer-wise dynamic coordinated inverse bottleneck structure is used to reduce the network feature loss. The inverse bottleneck structure makes the image information less lossy when transforming from different dimensional feature spaces. The fusion of multi-scale and layer-wise dynamic coordinated inverse bottlenecks makes the model effectively balances computational efficiency and feature representation capability, and more robust with a combination of horizontal and vertical features in the fine identification of apple leaf diseases. Finally, after each improved module, a triplet parallel attention module is integrated with cross-dimensional interactions among channels through rotations and residual transformations, which improves the parallel search efficiency of important features and the recognition rate of the network with relatively small computational costs while the dimensional dependencies are improved. To verify the validity of the model in this paper, we uniformly enhance apple leaf disease images screened from the public data sets of Plant Village, Baidu Flying Paddle, and the Internet. The final processed image count is 14,000. The ablation study, pre-processing comparison, and method comparison are conducted on the processed datasets. The experimental results demonstrate that the proposed method reaches 98.73% accuracy on the adopted datasets, which is 1.82% higher than the classical ResNet-50 model, and 0.29% better than the apple leaf disease datasets before preprocessing. It also achieves competitive results in apple leaf disease identification compared to some state-ofthe-art methods.展开更多
To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraff...To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraffin section method, the leaf thickness, the epidermis thickness, the palisade tissue thickness and the sponge tissue thickness were measured; palisade spongy ratio, Cell Tightness(CT) and Cell Looseness(CL) were examined after treatments with exogenous ABA. Leaf thickness, leaf palisade spongy ratio and palisade tissue thickness increased significantly after exogenous ABA treatment compared with CK, while the effect on leaf epidermis was not obvious. The leaf thickness and palisade tissue thickness increased evidently after 70 mg · LABA treatment by 24.89% and 41.10%, respectively. The tissue structures of leaves were more compact, while CL was lower after 70 and 90 mg · LABA treatments. The effects of different concentrations of exogenous ABA could increase the leaf thickness, palisade tissue thickness of Korla fragrant pear and CT, reduced the thickness of spongy tissue and CL. Among those concentrations of exogenous ABA, the effect of spraying 70 mg · Lexogenous ABA was suitable for improving cold resistance of Korla fragrant pear.展开更多
[ Objective] This study aimed to investigate the effects of different water and fertilizer combinations on apple saplings. [ Method] ' Tianhong 2' Fuji /SH40/Malus robusta Rehd. was used as the experimental material...[ Objective] This study aimed to investigate the effects of different water and fertilizer combinations on apple saplings. [ Method] ' Tianhong 2' Fuji /SH40/Malus robusta Rehd. was used as the experimental material to analyze the effects of different irrigation modes and combinations of basal fertilizer and dressing fertilizer on tree structure, leaf parameters and photosynthesis of apple saplings. [ Result] The results showed that different water and fertilizer combinations ex- hibited varying effects on tree structure, leaf parameters and photosynthesis of apple saplings. To be specific, applying 432 000 kg/hm2 basal fertilizer, 480 kg/hm2 urea and 915 kg/hmz organic fertilizer + 0 + 915 kg/hm2 organic fertilizer as dressing fertilizer, and 1% urea as leaf fertilizer was conducive to promoting growth of branches and leaves, increasing leaf thickness, individual leaf area and SPAD, and improving photosynthesis of apple saplings under half root irrigation and whole root irrigation conditions. In addition, the effects were more significant under whole root irrigation conditions. [ Conclusion] Selecting the appropriate water and fertilizer combination is conducive to the growth of apple saplings.展开更多
[Objective] This study was conducted to compare leaf anatomical structure of Malus sieversii and M. robusta under different salt concentration levels to determine their tolerance to salt and thus to provide rootstock ...[Objective] This study was conducted to compare leaf anatomical structure of Malus sieversii and M. robusta under different salt concentration levels to determine their tolerance to salt and thus to provide rootstock materials for apple production in salinized soil in Southern Xinjiang. [Method] The experiment was conducted with M. sieversii and M. robusta as test materials. Salt stress was simulated using 8 g/L of NaCI solution, and Hoagland nutrient solution was used instead of NaCI solution as control group (CK). Samples were collected on the 20^th d of treatment, sliced through paraffin processing. The prepared paraffin sections of M. sieversii and M. robusta were then observed under a light microscope for anatomical structures of leaf, upper epidermis, lower epidermis, palisade tissue and spongy tissue. [Result] Compared with the control, the leaf, upper epidermis, lower epidermis and spongy tissue of M. sieversii and M. robusta under salt stress were thickened at different degrees, while the thickness of the palisade tissue was decreased. Moreover, high salt concentration caused severer damage to the cell structure of M. sieversii than to that of M. robusta, as M. robusta cells maintained better structural integrity. [Conclusion] M. robusta has higher adaptability to salt stress than M. sieversii.展开更多
Ultra-thin electromagnetic wave(EMW)absorbers present challenging demands on EMW absorption performance.Drawing inspiration from heather leaf structures,this study introduces an innovative design strategy for EMW abso...Ultra-thin electromagnetic wave(EMW)absorbers present challenging demands on EMW absorption performance.Drawing inspiration from heather leaf structures,this study introduces an innovative design strategy for EMW absorbing material,proposing biomimetic leaf SnO_(2) structures(bio-SnO_(2))on carbon fabric(CF).By employing leaf-shaped SnS2 as precursors,biomimetic leaf SnO_(2) nanostructures are constructed on CF surface after a simple thermal treatment,resulting in bio-SnO_(2)@CF composite.Experimental results indicate that bio-SnO_(2)@CF exhibits an exceptional minimum reflection loss of-54.8 dB at an incredibly thin thickness of 1.2 mm.Radar cross section(RCS)simulations further validate the outstanding EMW attenuation ability of bio-SnO_(2)@CF,attaining a maximum RCS reduction value of 16.9 dBm^(2) at an incident wave angle ofθ=0°.This novel research showcases the biomimetic structural design strategy and its remarkable function in enhancing the EMW absorbing performance at ultra-thin absorber thickness.展开更多
Duyun Maojian tea is a famous tea in China.In this study,the specific-locus amplified fragment(SLAF)sequencing method was used to analyze the population structure and conduct a genome-wide association study(GWAS)of 2 ...Duyun Maojian tea is a famous tea in China.In this study,the specific-locus amplified fragment(SLAF)sequencing method was used to analyze the population structure and conduct a genome-wide association study(GWAS)of 2 leaf traits of 123 tea plants in Qiannan,China.A total of 462,019 SLAF tags and 11,362,041 single-nucleotide polymorphism(SNP)loci were obtained.The results of phylogenetic tree analysis,cluster analysis,and principal component analysis showed that 123 tea germplasms were clustered into three groups,and the heterozygosity rates for Groups I,II,and II were 0.206,0.224,and 0.34,respectively.Generally,tea germplasms in a production area are clustered in a group,indicating that tea germplasms in different production areas have certain genetic diversity.The traditional Duyun Maojian tea core production areas,TS and DC-SJ,are clustered into Group I and Group II respectively,while the ZY production area is relatively independent in Group III.Furthermore,based on GWAS analysis,11 candidate genes related to leaf apex and 7 candidate genes related to leaf shape were obtained.This study clarified the genetic relationship among eight Duyun Maojian tea production areas and obtained candidate genes related to leaf apex and leaf shape development.The results showed that population structure and candidate genes are an effective basis for the breeding of Duyun Maojian tea germplasm.展开更多
基金supported by the National Natural Science Foundation of China(No.32002195)Zhejiang Provincial Leading Innovation and Entrepreneurship Team Project(No.2020R01015)+1 种基金“Leading Geese”Research and Development Plan of Zhejiang Province(No.2022C02059)Key R&D Projects of Zhejiang Province(No.2021C02013)。
文摘Background Dietary bamboo leaf flavonoids(BLFs)are rarely used in poultry production,and it is unknown whether they influence meat texture profile,perceived color,or microstructure.Results A total of 720 one-day-old Arbor Acres broilers were supplemented with a basal diet with 20 mg bacitracin/kg,50 mg BLFs/kg,or 250 mg BLFs/kg or without additions.Data showed that the dietary BLFs significantly(P<0.05)changed growth performance and the texture profile.In particular,BLFs increased birds’average daily gain and average daily feed intake,decreased the feed:gain ratio and mortality rate,improved elasticity of breast meat,enhanced the gumminess of breast and leg meat,and decreased the hardness of breast meat.Moreover,a significant(P<0.05)increase in redness(a*)and chroma(c*)of breast meat and c*and water-holding capacity of leg meat was found in BLF-supplemented broilers compared with control broilers.In addition,BLFs supplementation significantly decreased(P<0.05)theβ-sheet ratio and serum malondialdehyde and increased theβ-turn ratio of protein secondary structure,superoxide dismutase,and glutathione peroxidase of breast meat and total antioxidant capacity and catalase of serum.Based on the analysis of untargeted metabolome,BLFs treatment considerably altered 14 metabolites of the breast meat,including flavonoids,amino acids,and organic acids,as well as phenolic and aromatic compounds.Conclusions Dietary BLFs supplementation could play a beneficial role in improving meat quality and sensory color in the poultry industry by changing protein secondary structures and modulating metabolites.
基金supported by the State Key Laboratory of Cotton Biology Open Fund,China(CB2021A18)the Youth Scientific Research Foundation of Shandong Academy of Agricultural Sciences,China(2016YQN09)+1 种基金the Improved Variety Project of Shandong Province,China(2020LZGC002)the China Agriculture Research System of MOF and MARA(CARS-15-05).
文摘One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on achieving high photosynthetic efficiency traits in order to enhance the yield.Leaf shape is a significant agronomic trait of upland cotton that affects plant and canopy architecture,yield,and other production attributes.The major leaf shape types,including normal,sub-okra,okra,and super-okra,with varying levels of lobe severity,are controlled by a multiple allelic series of the D-genome locus L-D_(1).To analyze the effects of L-D_(1)alleles on leaf morphology,photosynthetic related traits and yield of cotton,two sets of near isogenic lines(NILs)with different alleles were constructed in Lumianyan 22(LMY22)and Lumianyan 28(LMY28)backgrounds.The analysis of morphological parameters and the results of virus-induced gene silencing(VIGS)showed that the regulation of leaf shape by L-D_(1)alleles was similar to a gene-dosage effect.Compared with the normal leaf,deeper lobes of the sub-okra leaf improved plant canopy structure by decreasing the leaf area index(LAI)and increasing the light transmittance rate(LTR),and the mid-range LAI of sub-okra leaf also guaranteed the accumulation of cotton biomass.Although the chlorophyll content(SPAD)of sub-okra leaf was lower than those of the other two leaf shapes,the net photosynthetic rate(Pn)of sub-okra leaf was higher than those of okra leaf and normal leaf at most stages.Thus,the improvements in canopy structure,as well as photosynthetic and physiological characteristics,contributed to optimizing the light environment,thereby increasing the total biomass and yield in the lines with a sub-okra leaf shape.Our results suggest that the sub-okra leaf may have practical application in cultivating varieties,and could enhance sustainable and profitable cotton production.
文摘The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscope. Results showed that all leaves consisted of epidermis, chlorenchyma, aquiferous tissue and vascular bundles. The leaves had the xeromorphic characteristics, including thickened epidermal cell wall, thickened cuticle, sunken stomata and well-developed aquiferous tissue. With the exception of thus, there were remarkable differences in leaf structure among the six species. The chlorenchyma cells were similar to palisade tissues in Aloe arborescens Mill. and A. mutabilis Pillans, but isodiametric in A. vera L., A. vera L. var. chinensis Berg., A. saponaria Hawer and A. greenii Bali. A. arborescens, A. mutabilis, A. very and A. vera var. chinensis included large parenchymatous cells at the vascular bundles, whereas no such cells were observed at the vascular bundles of A. saponaria and A. greenii. In A. arborescens, A. mutabilis and A. vera, the aquiferous tissue sheaths were present and composed of a layer of small parenchymatous cells without chloroplasts around the aquiferous tissue. While there were no aquiferous tissue sheaths in A. vera var. chinensis, A. saponaria and A. greenii. The HPLC revealed that the content of aloin was high in A. arborescens, low in A. vera, and very low in A. saponaria among the six species. The fluorescent microscopy showed that the yellow-green globule only appeared in the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath, but not in the chlorenchyma and aquiferous tissue. Consequently, the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath were the storage location of aloin. They were positively correlated with the content of aloin.
基金Supported by the Scientific Research Innovation Fund for the Youth of Hunan Academy of Forestry(2013LQJ13)~~
文摘Plants usually suffer drought stress during their growth process. As the photosynthetic activity center of plants, the leaf is the most sensitive organ under drought stress. In order to support the research on drought resistance of higher plants, this study reviewed the adaptation response and damage performance of epidermal structure, palisade tissue and spongy tissue, thickness, veins and stomata of plant leaves under drought stress.
基金Supported by Guangxi Agricultural College Science Topics(B070206)~~
文摘[ Objective] Correlation of microstructure of leaf sheath epidermis and nutrient composition of palm plants with the damage degree of red palm fiber elephant in four kinds of plants in Nanning were analyzed in order to control the occurrence and damage of this insect in Nanning. [Method] Taken 4 kinds of Palmae plants in Nanning including Ravenea fivulafis, Washingtonia filifera, Phoenix canafiensis, Roystonea regia (HBK.)O. F. Cook as materials, damage situation of the red palm fiber elephant was investigated, microstructure of leaf sheath epidermis and nutrient composition of palm plants were analyzed and determined. [ Result] The results showed that there was direct correlation between the microstructure of leaf sheath epidermis and nutrient composition with the physical resistance of palm plant against red palm fiber elephant. The extend of damage from red palm fiber elephant had negatively relation with the thickness of corneum and leaf epidermis. The damage degree caused by red palm fiber elephant increased with the content of crude protein, crude ash and nitrogen free extract increasing, also increased with the content of rude fiber decreasing. [Condusion] The damage degree of red palm fiber elephant had a relationship with microstructure of leaf sheath epidermis and nutrient composition of palm plants.
文摘[Objective] This study aimed to investigate the effects of PP333 and ex- ogenous ABA on the growth and development of Armeniaca vulgaris 'Luntaibaixing' so as to provide a theoretical basis for the growth regulation of Luntaibaixing in cultivation and management. [Method} Different concentrations of PP333 and ABA were sprayed to Luntaibaixing during the rapid growth period of fresh treetops. The technology of paraffin section was used to measure the thickness of leaf, upper epidermis, lower epidermis, palisade tissue and sponge tissue. The thickness ratio of palisade tissue to sponge tissue, tightness degree of leaf tissue structure (CTR) and loose degree of leaf tissue structure (SR) were calculated and the differences in leaf tissue structure were analyzed. [Result] The thickness of leaf and palisade tissue both increased significantly after treated by PP333. At the treatment concen- tration of 1 000 mg/L, the thickness ratio of palisade tissue to sponge tissue and the value of CTR were highest, while the thickness of sponge tissue and the value of SR were lowest. The thickness of leaf and palisade tissue also increased after treated by ABA, and it increased most greatly at the ABA concentration of 60 mg/L compared with CK. At the treatment concentration of 60 rag/L, the thickness ratio of palisade tissue to sponge tissue and the value of CTR were the highest, while the thickness of sponge tissue and the value of SR were the lowest. [Conclusion] ABA and PP333 treatment increased the leaf thickness, palisade tissue thickness, pal- isade tissue to sponge tissue thickness ratio and CRT value, but reduced the sponge tissue thickness and SR value of Luntaibaixing.
基金Supported by National Natural Science Foundation of China(30370156)Yunnan Provincial Key Discipline of Ornamental Plants and Horticulture of Southwest Forestry University,Key Laboratories and School Laboratories Sharing Platform of Provincial Colleges~~
文摘[Objective] This study aimed to investigate the leaf anatomical structures of P. tunicoides populations under water-limited conditions. [Method] 2-year-old seedlings of herbaceous perennial P. tunicoides that was introduced into the experi- mental field were selected as the research objects. Under the well-watered and wa- ter-limited conditions, we conducted the comparative observation of leaf anatomical structure and stomatal characteristics of two populations by using paraffin slice method and imprinting method. [Result] The result showed that the upper cuticle of P. tunicoides leaves were thickened, the palisade tissue/spongy tissue ratio, vascular bundle diameter and number of xylem vessels in main vein had increased, the stomatal opening became smaller and the stomatal density had increased in winter- spring drought period under water-limited conditions. The plasticity of above traits could be regarded as the important indicators for detecting the responses of P. tunicoides populations to water-limited conditions. Meanwhile, variation amplitudes of these indicators were different among populations. Leaf anatomical structure and stomatal characteristics in Lijiang Axi population under water-limited conditions varied significantly, which might cause the stronger adaptability of this population to drought conditions. [Conclusion] This research provided a reference for the selection of drought-resistant P. tunicoides germplasm and exploration of the adaptive differentia- tion of P. tunicoides populations under natural drought conditions.
基金Supported by Natural Basic Research Program of Universities in Jiangsu(06KJD180201)~~
文摘The leaf development of Podocarpus macrophyllus var.maki Endl.started from the leaf primordium formed by the cell division in shoot apical meristem.During the leaf development,three resin canals from the inferior part of vascular bundles firstly began to differentiate,then protoxylem in vascular bundles differentiated from adaxial side to abaxial side.Meanwhile,a layer of parenchyma cells from the inferior part of protoderm developed into the sclerenchyma,which played an important role in supporting young leaves.When xylem became mature basically,transfusion tissue,phloem and accessory transfusion tissue began to differentiate,so mesophyll tissue finally differentiated into developmental palisade cells and sponge cells.The thicker cuticle was formed in the lateral side of epidermal cells at the same time of differentiation and development for the inner structure of leaves.Therefore,the developmental palisade cells and the cuticle in the leaf structure of Podocarpus macrophyllus var.maki Endl.is greatly significant for photosynthesis and transpiration when it grows in arid and cold regions.
基金supported by the National Natural Science Foundation of China (41975044)the Open Research Fund of the State Laboratory of Information Engineering in Surveying,Mapping,Remote Sensing,Wuhan University (20R02)+2 种基金the Fundamental Research Funds for the Central Universities,China University of Geosciences (Wuhan)(111-G1323520290)funded by SNSA (Dnr 96/16)the EU-Aid funded CASSECS Project。
文摘Leaf pigments are critical indicators of plant photosynthesis,stress,and physiological conditions.Inversion of radiative transfer models(RTMs)is a promising method for robustly retrieving leaf biochem-ical traits from canopy observations,and adding prior information has been effective in alleviating the“ill-posed”problem,a major challenge in model inversion.Canopy structure parameters,such as leaf area index(LAI)and average leaf inclination angle(ALA),can serve as prior information for leaf pigment retrie-val.Using canopy spectra simulated from the PROSAIL model,we estimated the effects of uncertainty in LAI and ALA used as prior information for lookup table-based inversions of leaf chlorophyll(C _(ab))and car-otenoid(C_(ar)).The retrieval accuracies of the two pigments were increased by use of the priors of LAI(RMSE of C_(ab) from 7.67 to 6.32μg cm^(-2),C_(ar) from 2.41 to 2.28μg cm^(-2))and ALA(RMSE of C_(ab) from 7.67 to 5.72μg cm^(-2),C_(ar) from 2.41 to 2.23μg cm^(-2)).However,this improvement deteriorated with an increase of additive and multiplicative uncertainties,and when 40% and 20% noise was added to LAI and ALA respectively,these priors ceased to increase retrieval accuracy.Validation using an experimental winter wheat dataset also showed that compared with C_(ar),the estimation accuracy of C_(ab) increased more or deteriorated less with uncertainty in prior canopy structure.This study demonstrates possible limita-tions of using prior information in RTM inversions for retrieval of leaf biochemistry,when large uncer-tainties are present.
文摘This paper focused on the influence of the shape and size of threshing frames as well as the grades of tobacco leaves on the structure of threshed leaves.The testing tobacco leaves all came from the hilly ecological region of Nanling and belonged to burnt sweet,alcoholic sweet and scent category.The comprehensive evaluating value S was taken as the test index.Results showed that,without considering the influence of tobacco grade on leaf structure,the shapes of first-stage thresher five-link frames were all hexagons,and the combination with the sizes of 3.5,3.0,3.5,3.0,3.0 inches had the highest evaluating value S of 2.49.For tobacco grade C2FH,the shapes of first-stage thresher five-link frames were also hexagons,and the evaluating value S reached the highest value of 3.40 with sizes of 3.5,3.0,3.5,3.0,3.0 inches.Comprehensive analysis showed that:3.0 inch frame performed better in controlling the percentage of large-sized strips than 3.5 inch frame did;rhombic frames were better than hexagon frames in reducing the breakage rate of tobacco leaves;different shapes or sizes of nonadjacent two-link frames can help to improve the threshing quality.
基金Supported by the Key Technologies Research and Development Program of China during the 12th Five-year Plan(2014BAD16B07)the Fund for Key Discipline of Horticultural Sciences of Xinjiang Uygur Autonomous RegionCentral Financial Forestry Science and Technology Promotion Project(ZYLTKJTG2015017)~~
文摘[Objective] This study was performed to explore the effect of different concentrations of PP333 on leaf tissue structure of Korla fragrant pear and to lay the foundation for the cultivation and regulation of Korla fragrant pear. [Method] The leaf tissues treated with different concentrations of PP333 were dehydrated with al- cohol, embedded in paraffin and sliced into 10-μm slices. The thicknesses of leaf blade, upper epidermis, lower epidermis, palisade tissue and sponge tissue were measured, and the ratio of palisade to spongy layer thickness, cell tightness (CT) and cell looseness (CL) were calculated. [Result] The thickness of leaf blade, the ratio of palisade to sponge layer thickness and the thickness of palisade layer were all significantly increased after treatment with PP333. Treatment with 2 500 mg/L PP333 showed no obvious effect on the thickness of leaf epidermis, but increased the thicknesses of leaf blade and palisade tissue. Leaf CL was the highest in the treatment of 1 500 mg/L PP333. [Conclusion] PP333 can increase the leaf thickness, palisade tissue thickness and CT, reduce spongy tissue thickness and CL of Korla fragrant pear. Additionally, 1 500 mg/L was the optimal concentration for the application of PP333 to improve the cold resistance of Koda fragrant pear.
基金Hunan Forestry Science and Technology Innovation Project(XLK201971)Changsha Science and Technology Program(kq1801028).
文摘[Objectives]This study was conducted to investigate the response of Gardenia to purple soil drought stress,hoping to provide a reference for the selection of plants for vegetation restoration in purple soil regions.[Methods]The pot-weighing water control method was used to apply different degrees of drought stress to Gardenia seedlings in purple soil,and the effects of drought stress on the electrical conductivity,chlorophyll content,leaf morphology and structure of Gardenia leaves were explored.[Results]The leaf electrical conductivity increased with the increase of drought stress intensity,and the leaf electrical conductivity under severe drought stress increased by 59.93%compared with the control;the chlorophyll content of Gardenia showed a single-peak changing trend that increased and then decreased with the development of drought stress,and it was the highest in each stress stage under severe drought stress;the leaf thickness,palisade tissue thickness and sponge tissue thickness of Gardenia were reduced with the stress degree increasing,and showed the largest decreases under severe stress;the stomatal length,stomatal width and stomatal opening of Gardenia gradually decreased with the increase of stress,while the stomatal density gradually increased.[Conclusions]This study provides a technical and resource basis for vegetation restoration in purple soil.
基金supported by the Natural ScienceFoundation of Jiangsu Province of China (Grant No.SBK2010294)an Open Project Program of Jiangsu Key Laboratory of the Ministry of Education for Plant Functional Genomics (Grant No. K10001)
文摘Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurring leaf-color rice mutant, Baihuaidao 7, was analyzed. Mutant plants typically exhibited a green-white-green leaf-color progression, but this phenotype was only expressed in the presence of a stress signal induced by mechanical scarification such as transplantation. Prior to the appearance of white ~eaves, mutant plant growth, leaf color, chlorophyll content, and chloroplast ultrastructure appeared to be identical to those of the wild type. After the changeover to white leaf color, an examination of the mutated leaves revealed a decrease in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoid content, a reduction in the number of chloroplast grana lamella and grana, and a gradual degradation of the thylakoid lamellas. At maturity, the mutant plant was etiolated and dwarfed compared with wild-type plants. Genetic analysis indicated that the leaf mutant character is controlled by a recessive nuclear gene. Genetic mapping of the mutant gene was performed using an F2 population derived from a Baihuaidao 7 ~ Jiangxi 1587 cross. The mutant gene was mapped to rice chromosome 11, positioned between InDel markers L59.2-7 and L64.8-11, which are separated by approximately 740.5 kb. The mutant gene is believed to be a new leaf-color mutant gene in rice, and is tentatively designated as gwgl.
基金funded by the EU Regional Development Fund within the framework of the Centre of Excellence EcolChange(2014-2020.4.01.15-0002),the European Commission through the European Research Council(advanced grant 322603,SIPVOL+),the Estonian Research Council(personal grant PSG884)base funding nr 190200,the National Natural Science foundation of China(31711530648)+2 种基金the Personnel Startup Project of the Scientific Research and Development Foundation of Zhejiang A&F University(2021FR041)the study was partly purchased from funding by the EU Regional Development Fund(AnaEE Estonia,2014-2020.4.01.20-0285,and the project“Plant Biology Infrastructure-TAIM”,2014-2020.4.01.20-0282)the Estonian Research Council(“Plant Biology Infrastructure-TAIM”,TT5).
文摘Leaf economics spectrum(LES)describes the fundamental trade-offs between leaf structural,chemical,and physiological investments.Generally,structurally robust thick leaves with high leaf dry mass per unit area(LMA)exhibit lower photosynthetic capacity per dry mass(Amass).Paradoxically,“soft and thinleaved”mosses and spikemosses have very low Amass,but due to minute-size foliage elements,their LMA and its components,leaf thickness(LT)and density(LD),have not been systematically estimated.Here,we characterized LES and associated traits in cryptogams in unprecedented details,covering five evolutionarily different lineages.We found that mosses and spikemosses had the lowest LMA and LT values ever measured for terrestrial plants.Across a broad range of species from different lineages,Amass and LD were negatively correlated.In contrast,Amass was only related to LMA when LMA was greater than 14 g cm^(-2).In fact,low Amass reflected high LD and cell wall thickness in the studied cryptogams.We conclude that evolutionarily old plant lineages attained poorly differentiated,ultrathin mesophyll by increasing LD.Across plant lineages,LD,not LMA,is the trait that represents the trade-off between leaf robustness and physiology in the LES.
基金supported in part by the General Program Hunan Provincial Natural Science Foundation of 2022,China(2022JJ31022)the Undergraduate Education Reform Project of Hunan Province,China(HNJG-20210532)the National Natural Science Foundation of China(62276276)。
文摘Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from image texture and structural information. The difficulties in disease feature extraction in complex backgrounds slow the related research progress. To address the problems, this paper proposes an improved multi-scale inverse bottleneck residual network model based on a triplet parallel attention mechanism, which is built upon ResNet-50, while improving and combining the inception module and ResNext inverse bottleneck blocks, to recognize seven types of apple leaf(including six diseases of alternaria leaf spot, brown spot, grey spot, mosaic, rust, scab, and one healthy). First, the 3×3 convolutions in some of the residual modules are replaced by multi-scale residual convolutions, the convolution kernels of different sizes contained in each branch of the multi-scale convolution are applied to extract feature maps of different sizes, and the outputs of these branches are multi-scale fused by summing to enrich the output features of the images. Second, the global layer-wise dynamic coordinated inverse bottleneck structure is used to reduce the network feature loss. The inverse bottleneck structure makes the image information less lossy when transforming from different dimensional feature spaces. The fusion of multi-scale and layer-wise dynamic coordinated inverse bottlenecks makes the model effectively balances computational efficiency and feature representation capability, and more robust with a combination of horizontal and vertical features in the fine identification of apple leaf diseases. Finally, after each improved module, a triplet parallel attention module is integrated with cross-dimensional interactions among channels through rotations and residual transformations, which improves the parallel search efficiency of important features and the recognition rate of the network with relatively small computational costs while the dimensional dependencies are improved. To verify the validity of the model in this paper, we uniformly enhance apple leaf disease images screened from the public data sets of Plant Village, Baidu Flying Paddle, and the Internet. The final processed image count is 14,000. The ablation study, pre-processing comparison, and method comparison are conducted on the processed datasets. The experimental results demonstrate that the proposed method reaches 98.73% accuracy on the adopted datasets, which is 1.82% higher than the classical ResNet-50 model, and 0.29% better than the apple leaf disease datasets before preprocessing. It also achieves competitive results in apple leaf disease identification compared to some state-ofthe-art methods.
基金Supported by Science and Technology Planning Projects of China during the 12th Five-year Plan-key Techniques of High Quality and High Efficiency Production of Fruit Trees(2014BAD16B07)Central Finance Forestry Science and Technology Extension Project(ZYLTKJTG2015017)National Featured Fruit Trees Root Stock Germplasm Resources Platform(Luntai)(NICGR2017-60)
文摘To study the effects of different concentrations of Abscisic Acid(ABA) on leaf tissue structure of Korla fragrant pear and lay the foundation for the cultivation and regulation of Korla fragrant pear. Using the paraffin section method, the leaf thickness, the epidermis thickness, the palisade tissue thickness and the sponge tissue thickness were measured; palisade spongy ratio, Cell Tightness(CT) and Cell Looseness(CL) were examined after treatments with exogenous ABA. Leaf thickness, leaf palisade spongy ratio and palisade tissue thickness increased significantly after exogenous ABA treatment compared with CK, while the effect on leaf epidermis was not obvious. The leaf thickness and palisade tissue thickness increased evidently after 70 mg · LABA treatment by 24.89% and 41.10%, respectively. The tissue structures of leaves were more compact, while CL was lower after 70 and 90 mg · LABA treatments. The effects of different concentrations of exogenous ABA could increase the leaf thickness, palisade tissue thickness of Korla fragrant pear and CT, reduced the thickness of spongy tissue and CL. Among those concentrations of exogenous ABA, the effect of spraying 70 mg · Lexogenous ABA was suitable for improving cold resistance of Korla fragrant pear.
基金Supported by National Modern Agricultural(Apple)Industry Technology System of China(CARS-28)
文摘[ Objective] This study aimed to investigate the effects of different water and fertilizer combinations on apple saplings. [ Method] ' Tianhong 2' Fuji /SH40/Malus robusta Rehd. was used as the experimental material to analyze the effects of different irrigation modes and combinations of basal fertilizer and dressing fertilizer on tree structure, leaf parameters and photosynthesis of apple saplings. [ Result] The results showed that different water and fertilizer combinations ex- hibited varying effects on tree structure, leaf parameters and photosynthesis of apple saplings. To be specific, applying 432 000 kg/hm2 basal fertilizer, 480 kg/hm2 urea and 915 kg/hmz organic fertilizer + 0 + 915 kg/hm2 organic fertilizer as dressing fertilizer, and 1% urea as leaf fertilizer was conducive to promoting growth of branches and leaves, increasing leaf thickness, individual leaf area and SPAD, and improving photosynthesis of apple saplings under half root irrigation and whole root irrigation conditions. In addition, the effects were more significant under whole root irrigation conditions. [ Conclusion] Selecting the appropriate water and fertilizer combination is conducive to the growth of apple saplings.
文摘[Objective] This study was conducted to compare leaf anatomical structure of Malus sieversii and M. robusta under different salt concentration levels to determine their tolerance to salt and thus to provide rootstock materials for apple production in salinized soil in Southern Xinjiang. [Method] The experiment was conducted with M. sieversii and M. robusta as test materials. Salt stress was simulated using 8 g/L of NaCI solution, and Hoagland nutrient solution was used instead of NaCI solution as control group (CK). Samples were collected on the 20^th d of treatment, sliced through paraffin processing. The prepared paraffin sections of M. sieversii and M. robusta were then observed under a light microscope for anatomical structures of leaf, upper epidermis, lower epidermis, palisade tissue and spongy tissue. [Result] Compared with the control, the leaf, upper epidermis, lower epidermis and spongy tissue of M. sieversii and M. robusta under salt stress were thickened at different degrees, while the thickness of the palisade tissue was decreased. Moreover, high salt concentration caused severer damage to the cell structure of M. sieversii than to that of M. robusta, as M. robusta cells maintained better structural integrity. [Conclusion] M. robusta has higher adaptability to salt stress than M. sieversii.
基金supported by Zhejiang Provincial Natural Science Foundation of China(Nos.LQ23F050006,LQ21E020005)the National Natural Science Foundation of China(No.52002365).
文摘Ultra-thin electromagnetic wave(EMW)absorbers present challenging demands on EMW absorption performance.Drawing inspiration from heather leaf structures,this study introduces an innovative design strategy for EMW absorbing material,proposing biomimetic leaf SnO_(2) structures(bio-SnO_(2))on carbon fabric(CF).By employing leaf-shaped SnS2 as precursors,biomimetic leaf SnO_(2) nanostructures are constructed on CF surface after a simple thermal treatment,resulting in bio-SnO_(2)@CF composite.Experimental results indicate that bio-SnO_(2)@CF exhibits an exceptional minimum reflection loss of-54.8 dB at an incredibly thin thickness of 1.2 mm.Radar cross section(RCS)simulations further validate the outstanding EMW attenuation ability of bio-SnO_(2)@CF,attaining a maximum RCS reduction value of 16.9 dBm^(2) at an incident wave angle ofθ=0°.This novel research showcases the biomimetic structural design strategy and its remarkable function in enhancing the EMW absorbing performance at ultra-thin absorber thickness.
基金This work was supported by the Science and Technology Foundation of Guizhou Province[20181044]the Construction Program of Biology First-Class Disciplining Guizhou(GNYL[2017]009)the Young Scholars and Technology Talents Development Project of Guizhou Education Department KY(2018)124,and the Independent Subject Grant Open Project of the Key Laboratory of Mountain Plant Resources Conservation and Plantation Innovation of the Ministry of Education(Guizhou University).
文摘Duyun Maojian tea is a famous tea in China.In this study,the specific-locus amplified fragment(SLAF)sequencing method was used to analyze the population structure and conduct a genome-wide association study(GWAS)of 2 leaf traits of 123 tea plants in Qiannan,China.A total of 462,019 SLAF tags and 11,362,041 single-nucleotide polymorphism(SNP)loci were obtained.The results of phylogenetic tree analysis,cluster analysis,and principal component analysis showed that 123 tea germplasms were clustered into three groups,and the heterozygosity rates for Groups I,II,and II were 0.206,0.224,and 0.34,respectively.Generally,tea germplasms in a production area are clustered in a group,indicating that tea germplasms in different production areas have certain genetic diversity.The traditional Duyun Maojian tea core production areas,TS and DC-SJ,are clustered into Group I and Group II respectively,while the ZY production area is relatively independent in Group III.Furthermore,based on GWAS analysis,11 candidate genes related to leaf apex and 7 candidate genes related to leaf shape were obtained.This study clarified the genetic relationship among eight Duyun Maojian tea production areas and obtained candidate genes related to leaf apex and leaf shape development.The results showed that population structure and candidate genes are an effective basis for the breeding of Duyun Maojian tea germplasm.