We subjected seeds and shoots of eelgrass Zostera marina to different combinations of sediment loosening(0(control),5,10 cm in depth)and sediment fertilization(0(control),40,80,120,160 g/m^(2))through a field experime...We subjected seeds and shoots of eelgrass Zostera marina to different combinations of sediment loosening(0(control),5,10 cm in depth)and sediment fertilization(0(control),40,80,120,160 g/m^(2))through a field experiment involving seed sowing and shoot transplantation from September 2020 to September 2021.Growth analysis revealed optimum ranges for sediment fertiliza-tion and sediment loosening were 88.8-93.8 g/m^(2)and 5.3-5.8 cm for Z.marina seed sowing,as well as 79.7-86.7 g/m^(2)and 5.9-6.5 cm for Z.marina shoot transplanting,respectively.The shoot densities of Z.marina exposed to these optimum range of sediment fer-tilization and sediment loosening were 1.1-1.3 times of those in the control group.Porewater nutrients are key environmental factors affecting seed germination and shoot growth of Z.marina.The results provide valuable insights for enhancing restoration effects of Z.marina.展开更多
The objective of the study was to determine the influence of temperature, relative humidity, and shoot size of Valencia orange trees Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae) on the abundance of eggs and nymp...The objective of the study was to determine the influence of temperature, relative humidity, and shoot size of Valencia orange trees Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae) on the abundance of eggs and nymphal stages of Diaphorina citri Kuwayama (Hemiptera: Liviidae). The experiment was established on 3.18 hectares cultivated with Valencia orange. The number of eggs, nymphs, temperature, relative humidity, and scale of the size of the shoot were recorded from January to July and from September to November 2020. The association of these variables was determined by multiple correspondence analyses. The conservation of the same number of individuals between consecutive samples and the increase in the number of eggs and nymphs was associated with temperature (17˚C - 23˚C), relative humidity (75% - 78%) and the availability of shoots from V1 to VS in March, April, June, and July. The largest number of N1 and N2 nymphs was recorded in January, February, May, and October. The highest population of eggs and nymphs N3 and N5 occurred in September. In November, there was a reduction in eggs and nymphs. Meanwhile, the nymph N4 was presented independently of the variables analyzed.展开更多
Many staple crops like wheat,soybeans,and maize stubbornly resist regrowing from lab-grown tissues-a major bottleneck for genetic modification and improvement of these crops.A Cell study in June 2024 may become a game...Many staple crops like wheat,soybeans,and maize stubbornly resist regrowing from lab-grown tissues-a major bottleneck for genetic modification and improvement of these crops.A Cell study in June 2024 may become a game-changer.Led by Dr.DENG Lei(Shandong Agricultural University)and Dr.LI Chuanyou(the CAS Institute of Genetics and Developmental Biology),the collaborative effort identified a peptide called REGENERATION FACTOR1(REF1)as a local wound signal that regulates damage-triggered tissue repair and organ regeneration.This very finding may greatly expand opportunities for improving crop resilience through targeted bioengineering.展开更多
Plants undergo dynamic morphological changes in response to fluctuating light conditions.Despite significant progress in elucidating the mechanisms of light signal transduction,the precise influence of light on the de...Plants undergo dynamic morphological changes in response to fluctuating light conditions.Despite significant progress in elucidating the mechanisms of light signal transduction,the precise influence of light on the development and regulation of shoot architecture remains a central research question.Studies focusing on model plants such as Arabidopsis thaliana and rice suggest light modulates shoot architecture through intricate regulatory networks.However,the molecular mechanisms governing the diverse effects of light on horticultural crops are still poorly understood.This review primarily focuses on horticultural crops,integrating research on model plants,including Arabidopsis and rice,to provide an overview of the regulatory mechanisms of light signals in plant architectural development.It also explores the prospects for manipulating light environments in greenhouse management strategies.展开更多
In order to improve the accuracy of the photogrammetric joint roughness coefficient(JRC)value,the present study proposed a novel method combining an autonomous shooting parameter selection algorithm with a composite e...In order to improve the accuracy of the photogrammetric joint roughness coefficient(JRC)value,the present study proposed a novel method combining an autonomous shooting parameter selection algorithm with a composite error model.Firstly,according to the depth map-based photogrammetric theory,the estimation of JRC from a three-dimensional(3D)digital surface model of rock discontinuities was presented.Secondly,an automatic shooting parameter selection algorithm was novelly proposed to establish the 3D model dataset of rock discontinuities with varying shooting parameters and target sizes.Meanwhile,the photogrammetric tests were performed with custom-built equipment capable of adjusting baseline lengths,and a total of 36 sets of JRC data was gathered via a combination of laboratory and field tests.Then,by combining the theory of point cloud coordinate computation error with the equation of JRC calculation,a composite error model controlled by the shooting parameters was proposed.This newly proposed model was validated via the 3D model dataset,demonstrating the capability to correct initially obtained JRC values solely based on shooting parameters.Furthermore,the implementation of this correction can significantly reduce errors in JRC values obtained via photographic measurement.Subsequently,our proposed error model was integrated into the shooting parameter selection algorithm,thus improving the rationality and convenience of selecting suitable shooting parameter combinations when dealing with target rock masses with different sizes.Moreover,the optimal combination of three shooting parameters was offered.JRC values resulting from various combinations of shooting parameters were verified by comparing them with 3D laser scan data.Finally,the application scope and limitations of the newly proposed approach were further addressed.展开更多
Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the tea.Traditional tea-picking machines may compromise the quality of the tea leaves.High-quality teas are often...Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the tea.Traditional tea-picking machines may compromise the quality of the tea leaves.High-quality teas are often handpicked and need more delicate operations in intelligent picking machines.Compared with traditional image processing techniques,deep learning models have stronger feature extraction capabilities,and better generalization and are more suitable for practical tea shoot harvesting.However,current research mostly focuses on shoot detection and cannot directly accomplish end-to-end shoot segmentation tasks.We propose a tea shoot instance segmentation model based on multi-scale mixed attention(Mask2FusionNet)using a dataset from the tea garden in Hangzhou.We further analyzed the characteristics of the tea shoot dataset,where the proportion of small to medium-sized targets is 89.9%.Our algorithm is compared with several mainstream object segmentation algorithms,and the results demonstrate that our model achieves an accuracy of 82%in recognizing the tea shoots,showing a better performance compared to other models.Through ablation experiments,we found that ResNet50,PointRend strategy,and the Feature Pyramid Network(FPN)architecture can improve performance by 1.6%,1.4%,and 2.4%,respectively.These experiments demonstrated that our proposed multi-scale and point selection strategy optimizes the feature extraction capability for overlapping small targets.The results indicate that the proposed Mask2FusionNet model can perform the shoot segmentation in unstructured environments,realizing the individual distinction of tea shoots,and complete extraction of the shoot edge contours with a segmentation accuracy of 82.0%.The research results can provide algorithmic support for the segmentation and intelligent harvesting of premium tea shoots at different scales.展开更多
Microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS) method was used to determine the contents of 25 inorganic elements in basal part, meat and shell of bamboo shoots. It could be concluded th...Microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS) method was used to determine the contents of 25 inorganic elements in basal part, meat and shell of bamboo shoots. It could be concluded that the method could be applied to determine 25 inorganic elements in bamboo shoots. The elements with a dry basis content higher than 10 mg/kg were listed in the order of content decrease as follows, basal part of bamboo shoots: K > Ca > Mg > Mn > P > Al > Fe > Zn > Na;bamboo shoots meat: K > P > Ca > Mg > Mn > Fe > Al > Zn > Na > Ba > Sr;bamboo shoots shell: K > P > Mg > Ca > Mn > Al > Fe > Na > Zn;B, Pb, Cu, Cr ranged from 1.0 - 10 mg/kg;Ga, As, Se, Cd, Sn, Sb, V, Co, Ni were lower than 0.80 mg/kg. The harmful elements Cd, As, Cr, Hg, Pb were commonly monitored in feeds. The wet basis content (mg/kg) of Cd, As, Cr was lower than: 0.028, 0.022 and 0.42 respectively;no Hg was found;the content of Pb(mg/kg) in basal part, meat and shell of bamboo shoots was 0.82, 0.35 and 0.41 respectively. The results provide basic data for the development of bamboo shoots and its byproduct.展开更多
Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a s...Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming conditions.The reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efficiency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by warming.However,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and non-stoma.Consequently,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of buds.Overall,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides.展开更多
This study looks at the prevalence of swollen shoot disease in cocoa plantations in the Marahoué region of Côte d’Ivoire, a key cocoa-producing area. Cocoa accounts for around a third of the country’s expo...This study looks at the prevalence of swollen shoot disease in cocoa plantations in the Marahoué region of Côte d’Ivoire, a key cocoa-producing area. Cocoa accounts for around a third of the country’s export earnings, but production is under threat from the swollen shoot virus, which is causing major yield reductions. The aim of the study is to establish a link between the chemical properties of the soil and the presence of the disease, in particular the levels of carbon, nitrogen, phosphorus, calcium and acidity (pH) in the soil. Specifically, soils from healthy plots were compared with soils from infested plots in six plantations in the Bouaflé and Kononfla sub-prefectures. The results show that soils from infested plots have lower phosphorus levels and near-neutral acidity in the 20 - 40 cm soil layer, while soils from healthy plots are slightly acidic and contain more calcium and phosphorus. These chemical differences seem to influence the prevalence of the virus. Low phosphorus levels appear to be a key factor in the vulnerability of cocoa trees to the disease. The study therefore suggests that any strategy to combat swollen shoot should include better soil management, incorporating factors such as soil depth and the availability of essential nutrients. In addition, an assessment of the micro-organisms present in the soil could provide further information on the interactions between the soil and the disease.展开更多
The orchards usually have rough terrain,dense tree canopy and weeds.It is hard to use GNSS for autonomous navigation in orchard due to signal occlusion,multipath effect,and radio frequency interference.To achieve auto...The orchards usually have rough terrain,dense tree canopy and weeds.It is hard to use GNSS for autonomous navigation in orchard due to signal occlusion,multipath effect,and radio frequency interference.To achieve autonomous navigation in orchard,a visual navigation method based on multiple images at different shooting angles is proposed in this paper.A dynamic image capturing device is designed for camera installation and multiple images can be shot at different angles.Firstly,the obtained orchard images are classified into sky and soil detection stage.Each image is transformed to HSV space and initially segmented into sky,canopy and soil regions by median filtering and morphological processing.Secondly,the sky and soil regions are extracted by the maximum connected region algorithm,and the region edges are detected and filtered by the Canny operator.Thirdly,the navigation line in the current frame is extracted by fitting the region coordinate points.Then the dynamic weighted filtering algorithm is used to extract the navigation line for the soil and sky detection stage,respectively,and the navigation line for the sky detection stage is mirrored to the soil region.Finally,the Kalman filter algorithm is used to fuse and extract the final navigation path.The test results on 200 images show that the accuracy of visual navigation path fitting is 95.5%,and single frame image processing costs 60 ms,which meets the real-time and robustness requirements of navigation.The visual navigation experiments in Camellia oleifera orchard show that when the driving speed is 0.6 m/s,the maximum tracking offset of visual navigation in weed-free and weedy environments is 0.14 m and 0.24 m,respectively,and the RMSE is 30 mm and 55 mm,respectively.展开更多
The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-...The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.展开更多
[Objective] The aim was to study the effect of apple-tea intercrop on the growth and yield of tea shoot.[Method] Comparing tea leaves in apple-tea intercrop garden with neighboring tea leaves,the change of tea growth ...[Objective] The aim was to study the effect of apple-tea intercrop on the growth and yield of tea shoot.[Method] Comparing tea leaves in apple-tea intercrop garden with neighboring tea leaves,the change of tea growth and fresh leaves yield in annual growth cycle was observed.[Result] There was obvious difference of tea shoot growth in intercropping and control group in various seasons.In spring,summer and autumn,intercropping tea had lower canopy temperature and higher canopy humidity compared with control tea,while there was no obvious difference of canopy temperature and humidity in intercropping and control tea in winter;the respiratory intensity of intercropping tea was very significantly lower than that of control tea,and its net photosynthetic intensity was very significantly higher than that of control tea,while there was no obvious change law in photosynthetic rate;the effect of intercrop on budding density of tea shoot wasn＇t obvious,but it promoted early germination of tea bud,increased leaf weight and improved fresh leaf yield.[Conclusion] Our study could provide theoretical foundation for the rational allocation of intercrop in compound ecological tea garden and the production of non-polluted tea.展开更多
Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was...Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.展开更多
An ACC synthase cDNA isolated from tomato (Lycopersicum esculentum Mill.) fruit was constructed in antisense orientation under the transcriptional control of CaMV 35S promoter and then introduced into tobacco (Nicotia...An ACC synthase cDNA isolated from tomato (Lycopersicum esculentum Mill.) fruit was constructed in antisense orientation under the transcriptional control of CaMV 35S promoter and then introduced into tobacco (Nicotiana tabacum L.) . PCR amplification demonstrated the integration of this antisense gene in tobacco genomes. Northern hybridization and reverse transcription-PCR analyses indicated the expression of this heterologous antisense gene in the transgenic tobacco tissues, which caused a decrease in the ethylene production, particularly when shoot regeneration exhibited. The ability of shoot regeneration of the transgenic plant during the culture process was enhanced remarkably as compared with that of the control. These results indicate at the molecular level that ethylene may play a regulatory role in shoot formation.展开更多
The time course of the initiation of different types of apical primordia on the stem of wheat (Triticum aestivum L.) was investigated to establish a comprehensive pattern of apical primordium development and quantitat...The time course of the initiation of different types of apical primordia on the stem of wheat (Triticum aestivum L.) was investigated to establish a comprehensive pattern of apical primordium development and quantitative dynamic relationships among different primordium initiation. The results showed that the initiation of leaf and bracteal primordia took the S shape, and that of spikelet and floret took the rise stage of parabolic shape in relation to GDD (growing degree days after sowing) in wheat. The bracteal was much like vegetative rather than reproductive organ in terms of the dynamic pattern of primordium initiation. The progress of spikelet and floret primordium initiation could well reflect the characteristics of different genotypes and the impact of different ecological environments on wheat apical development. The integrated model of different primordium initiation in shoot of wheat was an S_shaped curvilinear, and could be divided into three sub_models. The number of leaf primordia was affected by both genotype and environment, while the numbers of bracteal, spikelet and floret primordia were affected mainly by environmental factors. Measured with mean thermochron, the rates of initiation of leaf, bracteal and spikelet primordia in normal planting were the highest among all the sowing date treatments. In contrast to the relationships among leaf, bracteal, spikelet and their initiation duration, the correlation between the number of floret and its initiation duration was highly significant.展开更多
[Objective] This study aimed to establish a technology system for tissue culture and rapid propagation of Illciaceae ornamental plants. [Method] Effects of medium components and anti-browning agents on the survival an...[Objective] This study aimed to establish a technology system for tissue culture and rapid propagation of Illciaceae ornamental plants. [Method] Effects of medium components and anti-browning agents on the survival and growth of shoot tips were investigated by using apical buds of IItciaceae plant Haierlian as experiment material and MS as basic medium. [Result] The results showed that apical buds at the early germination period in spring were the most suitable explants for tissue culture of IIIciaceae plant Haierlian. Sterilization with 0.1% HgCI2 for 6 min achieved the best effect, while conventional surface-sterilization with ethanol would affect the survival of explants. The optimal medium for primary culture was MS-D （with modifications in major elements and organic components） ＋ anti-browning agents （equa~ volume） ＋ 2.0 mg/L of 6-BA ＋ 0.5 mg/L of NAA. The optimal subculture medi- um was MS-F （with modifications in inorganic and organic components） ＋ anti-brown- ing agents （equal volume） ＋ 2.0 mg/L of 6-BA ＋ 0.1 mg/L of NAA. [Conclusion] This study laid the foundation for establishment of tissue culture and rapid propagation technology system for Haierlian.展开更多
基金supported by the National Key Re-search and Development Program of China(No.2023 YFD2401102)the National Natural Science Foundation of China(No.42076100)the Joint Research Center for Conservation,Restoration&Sustainable Utilization of Marine Ecology of Ocean University of China-China State Shipbuilding Corporation Environmental Development Co.,Ltd.(No.H20240008).
文摘We subjected seeds and shoots of eelgrass Zostera marina to different combinations of sediment loosening(0(control),5,10 cm in depth)and sediment fertilization(0(control),40,80,120,160 g/m^(2))through a field experiment involving seed sowing and shoot transplantation from September 2020 to September 2021.Growth analysis revealed optimum ranges for sediment fertiliza-tion and sediment loosening were 88.8-93.8 g/m^(2)and 5.3-5.8 cm for Z.marina seed sowing,as well as 79.7-86.7 g/m^(2)and 5.9-6.5 cm for Z.marina shoot transplanting,respectively.The shoot densities of Z.marina exposed to these optimum range of sediment fer-tilization and sediment loosening were 1.1-1.3 times of those in the control group.Porewater nutrients are key environmental factors affecting seed germination and shoot growth of Z.marina.The results provide valuable insights for enhancing restoration effects of Z.marina.
文摘The objective of the study was to determine the influence of temperature, relative humidity, and shoot size of Valencia orange trees Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae) on the abundance of eggs and nymphal stages of Diaphorina citri Kuwayama (Hemiptera: Liviidae). The experiment was established on 3.18 hectares cultivated with Valencia orange. The number of eggs, nymphs, temperature, relative humidity, and scale of the size of the shoot were recorded from January to July and from September to November 2020. The association of these variables was determined by multiple correspondence analyses. The conservation of the same number of individuals between consecutive samples and the increase in the number of eggs and nymphs was associated with temperature (17˚C - 23˚C), relative humidity (75% - 78%) and the availability of shoots from V1 to VS in March, April, June, and July. The largest number of N1 and N2 nymphs was recorded in January, February, May, and October. The highest population of eggs and nymphs N3 and N5 occurred in September. In November, there was a reduction in eggs and nymphs. Meanwhile, the nymph N4 was presented independently of the variables analyzed.
文摘Many staple crops like wheat,soybeans,and maize stubbornly resist regrowing from lab-grown tissues-a major bottleneck for genetic modification and improvement of these crops.A Cell study in June 2024 may become a game-changer.Led by Dr.DENG Lei(Shandong Agricultural University)and Dr.LI Chuanyou(the CAS Institute of Genetics and Developmental Biology),the collaborative effort identified a peptide called REGENERATION FACTOR1(REF1)as a local wound signal that regulates damage-triggered tissue repair and organ regeneration.This very finding may greatly expand opportunities for improving crop resilience through targeted bioengineering.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.32330094,U21A20233,323B2057)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(Grant No.SN-ZJUSIAS-0011).
文摘Plants undergo dynamic morphological changes in response to fluctuating light conditions.Despite significant progress in elucidating the mechanisms of light signal transduction,the precise influence of light on the development and regulation of shoot architecture remains a central research question.Studies focusing on model plants such as Arabidopsis thaliana and rice suggest light modulates shoot architecture through intricate regulatory networks.However,the molecular mechanisms governing the diverse effects of light on horticultural crops are still poorly understood.This review primarily focuses on horticultural crops,integrating research on model plants,including Arabidopsis and rice,to provide an overview of the regulatory mechanisms of light signals in plant architectural development.It also explores the prospects for manipulating light environments in greenhouse management strategies.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52225904 and 52039007)the Fundamental Research Funds for the Central Universities,CHD(Grant No.300102212207).
文摘In order to improve the accuracy of the photogrammetric joint roughness coefficient(JRC)value,the present study proposed a novel method combining an autonomous shooting parameter selection algorithm with a composite error model.Firstly,according to the depth map-based photogrammetric theory,the estimation of JRC from a three-dimensional(3D)digital surface model of rock discontinuities was presented.Secondly,an automatic shooting parameter selection algorithm was novelly proposed to establish the 3D model dataset of rock discontinuities with varying shooting parameters and target sizes.Meanwhile,the photogrammetric tests were performed with custom-built equipment capable of adjusting baseline lengths,and a total of 36 sets of JRC data was gathered via a combination of laboratory and field tests.Then,by combining the theory of point cloud coordinate computation error with the equation of JRC calculation,a composite error model controlled by the shooting parameters was proposed.This newly proposed model was validated via the 3D model dataset,demonstrating the capability to correct initially obtained JRC values solely based on shooting parameters.Furthermore,the implementation of this correction can significantly reduce errors in JRC values obtained via photographic measurement.Subsequently,our proposed error model was integrated into the shooting parameter selection algorithm,thus improving the rationality and convenience of selecting suitable shooting parameter combinations when dealing with target rock masses with different sizes.Moreover,the optimal combination of three shooting parameters was offered.JRC values resulting from various combinations of shooting parameters were verified by comparing them with 3D laser scan data.Finally,the application scope and limitations of the newly proposed approach were further addressed.
基金This research was supported by the National Natural Science Foundation of China No.62276086the National Key R&D Program of China No.2022YFD2000100Zhejiang Provincial Natural Science Foundation of China under Grant No.LTGN23D010002.
文摘Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the tea.Traditional tea-picking machines may compromise the quality of the tea leaves.High-quality teas are often handpicked and need more delicate operations in intelligent picking machines.Compared with traditional image processing techniques,deep learning models have stronger feature extraction capabilities,and better generalization and are more suitable for practical tea shoot harvesting.However,current research mostly focuses on shoot detection and cannot directly accomplish end-to-end shoot segmentation tasks.We propose a tea shoot instance segmentation model based on multi-scale mixed attention(Mask2FusionNet)using a dataset from the tea garden in Hangzhou.We further analyzed the characteristics of the tea shoot dataset,where the proportion of small to medium-sized targets is 89.9%.Our algorithm is compared with several mainstream object segmentation algorithms,and the results demonstrate that our model achieves an accuracy of 82%in recognizing the tea shoots,showing a better performance compared to other models.Through ablation experiments,we found that ResNet50,PointRend strategy,and the Feature Pyramid Network(FPN)architecture can improve performance by 1.6%,1.4%,and 2.4%,respectively.These experiments demonstrated that our proposed multi-scale and point selection strategy optimizes the feature extraction capability for overlapping small targets.The results indicate that the proposed Mask2FusionNet model can perform the shoot segmentation in unstructured environments,realizing the individual distinction of tea shoots,and complete extraction of the shoot edge contours with a segmentation accuracy of 82.0%.The research results can provide algorithmic support for the segmentation and intelligent harvesting of premium tea shoots at different scales.
文摘Microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS) method was used to determine the contents of 25 inorganic elements in basal part, meat and shell of bamboo shoots. It could be concluded that the method could be applied to determine 25 inorganic elements in bamboo shoots. The elements with a dry basis content higher than 10 mg/kg were listed in the order of content decrease as follows, basal part of bamboo shoots: K > Ca > Mg > Mn > P > Al > Fe > Zn > Na;bamboo shoots meat: K > P > Ca > Mg > Mn > Fe > Al > Zn > Na > Ba > Sr;bamboo shoots shell: K > P > Mg > Ca > Mn > Al > Fe > Na > Zn;B, Pb, Cu, Cr ranged from 1.0 - 10 mg/kg;Ga, As, Se, Cd, Sn, Sb, V, Co, Ni were lower than 0.80 mg/kg. The harmful elements Cd, As, Cr, Hg, Pb were commonly monitored in feeds. The wet basis content (mg/kg) of Cd, As, Cr was lower than: 0.028, 0.022 and 0.42 respectively;no Hg was found;the content of Pb(mg/kg) in basal part, meat and shell of bamboo shoots was 0.82, 0.35 and 0.41 respectively. The results provide basic data for the development of bamboo shoots and its byproduct.
基金funded by the NSFC(32371669)the Science and Technology Talent Project for Distinguished Young Scholars of Jilin Province(20240602009RC)+1 种基金the NSF of Jilin Province(20240101207JC)the Scientific Research Project of the Department of Education,Jilin Province(JJKH20230687KJ).
文摘Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming conditions.The reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efficiency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by warming.However,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and non-stoma.Consequently,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of buds.Overall,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides.
文摘This study looks at the prevalence of swollen shoot disease in cocoa plantations in the Marahoué region of Côte d’Ivoire, a key cocoa-producing area. Cocoa accounts for around a third of the country’s export earnings, but production is under threat from the swollen shoot virus, which is causing major yield reductions. The aim of the study is to establish a link between the chemical properties of the soil and the presence of the disease, in particular the levels of carbon, nitrogen, phosphorus, calcium and acidity (pH) in the soil. Specifically, soils from healthy plots were compared with soils from infested plots in six plantations in the Bouaflé and Kononfla sub-prefectures. The results show that soils from infested plots have lower phosphorus levels and near-neutral acidity in the 20 - 40 cm soil layer, while soils from healthy plots are slightly acidic and contain more calcium and phosphorus. These chemical differences seem to influence the prevalence of the virus. Low phosphorus levels appear to be a key factor in the vulnerability of cocoa trees to the disease. The study therefore suggests that any strategy to combat swollen shoot should include better soil management, incorporating factors such as soil depth and the availability of essential nutrients. In addition, an assessment of the micro-organisms present in the soil could provide further information on the interactions between the soil and the disease.
基金National Key Research and Development Program of China(2022YFD2202103)National Natural Science Foundation of China(31971798)+2 种基金Zhejiang Provincial Key Research&Development Plan(2023C02049、2023C02053)SNJF Science and Technology Collaborative Program of Zhejiang Province(2022SNJF017)Hangzhou Agricultural and Social Development Research Project(202203A03)。
文摘The orchards usually have rough terrain,dense tree canopy and weeds.It is hard to use GNSS for autonomous navigation in orchard due to signal occlusion,multipath effect,and radio frequency interference.To achieve autonomous navigation in orchard,a visual navigation method based on multiple images at different shooting angles is proposed in this paper.A dynamic image capturing device is designed for camera installation and multiple images can be shot at different angles.Firstly,the obtained orchard images are classified into sky and soil detection stage.Each image is transformed to HSV space and initially segmented into sky,canopy and soil regions by median filtering and morphological processing.Secondly,the sky and soil regions are extracted by the maximum connected region algorithm,and the region edges are detected and filtered by the Canny operator.Thirdly,the navigation line in the current frame is extracted by fitting the region coordinate points.Then the dynamic weighted filtering algorithm is used to extract the navigation line for the soil and sky detection stage,respectively,and the navigation line for the sky detection stage is mirrored to the soil region.Finally,the Kalman filter algorithm is used to fuse and extract the final navigation path.The test results on 200 images show that the accuracy of visual navigation path fitting is 95.5%,and single frame image processing costs 60 ms,which meets the real-time and robustness requirements of navigation.The visual navigation experiments in Camellia oleifera orchard show that when the driving speed is 0.6 m/s,the maximum tracking offset of visual navigation in weed-free and weedy environments is 0.14 m and 0.24 m,respectively,and the RMSE is 30 mm and 55 mm,respectively.
文摘The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.
基金Supported by National Key Technology R&D Program(2007BAD87B11)Project of Science & Technology Bureau in Xishuangbanna(YX200902)Project of National Tea Industry Technical System~~
文摘[Objective] The aim was to study the effect of apple-tea intercrop on the growth and yield of tea shoot.[Method] Comparing tea leaves in apple-tea intercrop garden with neighboring tea leaves,the change of tea growth and fresh leaves yield in annual growth cycle was observed.[Result] There was obvious difference of tea shoot growth in intercropping and control group in various seasons.In spring,summer and autumn,intercropping tea had lower canopy temperature and higher canopy humidity compared with control tea,while there was no obvious difference of canopy temperature and humidity in intercropping and control tea in winter;the respiratory intensity of intercropping tea was very significantly lower than that of control tea,and its net photosynthetic intensity was very significantly higher than that of control tea,while there was no obvious change law in photosynthetic rate;the effect of intercrop on budding density of tea shoot wasn＇t obvious,but it promoted early germination of tea bud,increased leaf weight and improved fresh leaf yield.[Conclusion] Our study could provide theoretical foundation for the rational allocation of intercrop in compound ecological tea garden and the production of non-polluted tea.
文摘Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.
基金This work was supported by the Chinese National Key ScienceTechnology Projects in the Eighth-Five Year Plan
文摘An ACC synthase cDNA isolated from tomato (Lycopersicum esculentum Mill.) fruit was constructed in antisense orientation under the transcriptional control of CaMV 35S promoter and then introduced into tobacco (Nicotiana tabacum L.) . PCR amplification demonstrated the integration of this antisense gene in tobacco genomes. Northern hybridization and reverse transcription-PCR analyses indicated the expression of this heterologous antisense gene in the transgenic tobacco tissues, which caused a decrease in the ethylene production, particularly when shoot regeneration exhibited. The ability of shoot regeneration of the transgenic plant during the culture process was enhanced remarkably as compared with that of the control. These results indicate at the molecular level that ethylene may play a regulatory role in shoot formation.
文摘The time course of the initiation of different types of apical primordia on the stem of wheat (Triticum aestivum L.) was investigated to establish a comprehensive pattern of apical primordium development and quantitative dynamic relationships among different primordium initiation. The results showed that the initiation of leaf and bracteal primordia took the S shape, and that of spikelet and floret took the rise stage of parabolic shape in relation to GDD (growing degree days after sowing) in wheat. The bracteal was much like vegetative rather than reproductive organ in terms of the dynamic pattern of primordium initiation. The progress of spikelet and floret primordium initiation could well reflect the characteristics of different genotypes and the impact of different ecological environments on wheat apical development. The integrated model of different primordium initiation in shoot of wheat was an S_shaped curvilinear, and could be divided into three sub_models. The number of leaf primordia was affected by both genotype and environment, while the numbers of bracteal, spikelet and floret primordia were affected mainly by environmental factors. Measured with mean thermochron, the rates of initiation of leaf, bracteal and spikelet primordia in normal planting were the highest among all the sowing date treatments. In contrast to the relationships among leaf, bracteal, spikelet and their initiation duration, the correlation between the number of floret and its initiation duration was highly significant.
基金Supported by Suzhou Agricultural Scientific and Technological Project(SNY201001)~~
文摘[Objective] This study aimed to establish a technology system for tissue culture and rapid propagation of Illciaceae ornamental plants. [Method] Effects of medium components and anti-browning agents on the survival and growth of shoot tips were investigated by using apical buds of IItciaceae plant Haierlian as experiment material and MS as basic medium. [Result] The results showed that apical buds at the early germination period in spring were the most suitable explants for tissue culture of IIIciaceae plant Haierlian. Sterilization with 0.1% HgCI2 for 6 min achieved the best effect, while conventional surface-sterilization with ethanol would affect the survival of explants. The optimal medium for primary culture was MS-D （with modifications in major elements and organic components） ＋ anti-browning agents （equa~ volume） ＋ 2.0 mg/L of 6-BA ＋ 0.5 mg/L of NAA. The optimal subculture medi- um was MS-F （with modifications in inorganic and organic components） ＋ anti-brown- ing agents （equal volume） ＋ 2.0 mg/L of 6-BA ＋ 0.1 mg/L of NAA. [Conclusion] This study laid the foundation for establishment of tissue culture and rapid propagation technology system for Haierlian.
