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Multi-Scale Mixed Attention Tea Shoot Instance Segmentation Model
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作者 Dongmei Chen Peipei Cao +5 位作者 Lijie Yan Huidong Chen Jia Lin Xin Li Lin Yuan Kaihua Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期261-275,共15页
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
关键词 Tea shoots attention mechanism multi-scale feature extraction instance segmentation deep learning
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Core clock component MtLUX controls shoot architecture through repression of MtTB1/MtTCP1A in Medicago truncatula 被引量:2
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作者 Liping Wang Anqi Zhou +7 位作者 Lulu Wang Jing Li Mingkang Yang Tingting Duan Jian Jin Liang Chen Liangfa Ge Wei Huang 《The Crop Journal》 SCIE CSCD 2023年第3期723-732,共10页
Plants are capable of regulating their shoot architecture in response to diverse internal and external environments.The circadian clock is an adaptive mechanism that integrates information from internal and ambient co... Plants are capable of regulating their shoot architecture in response to diverse internal and external environments.The circadian clock is an adaptive mechanism that integrates information from internal and ambient conditions to help plants cope with recurring environmental fluctuations.Despite the current understanding of plant circadian clock and genetic framework underlying plant shoot architecture,the intricate connection between these two adaptive mechanisms remains largely unclear.In this study,we elucidated how the core clock gene LUX ARRHYTHMO(LUX)regulates shoot architecture in the model legume plant Medicago truncatula.We show that mtlux mutant displays increased main stem height,reduced lateral shoot length,and decreased the number of lateral branches and biomass yield.Gene expression analysis revealed that Mt LUX regulated shoot architecture by repressing the expression of strigolactone receptor MtD14 and MtTB1/MtTCP1A,a TCP gene that functions centrally in modulating shoot architecture.In vivo and in vitro experiments showed that Mt LUX directly binds to a cis-element in the promoter of MtTB1/MtTCP1A,suggesting that Mt LUX regulates branching by rhythmically suppressing MtTB1/MtTCP1A.This work demonstrates the regulatory effect of the circadian clock on shoot architecture,offering a new understanding underlying the genetic basis towards the flexibility of plant shoot architecture. 展开更多
关键词 Medicago truncatula Circadian clock MtLUX shoot architecture MtTB1/MtTCP1A
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Determination of Inorganic Elements Content and Distribution in Bamboo Shoots by Microwave Digestion and ICP-MS 被引量:2
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作者 Jianzhi Ye Zipeng Su +3 位作者 Ling Lin Yubing Zha Mingyue Wang Chunliang Yang 《Journal of Agricultural Chemistry and Environment》 2016年第3期152-157,共6页
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
关键词 Bamboo shoots Basal Part of Bamboo shoots Bamboo shoots Meat Bamboo shoots Shell Inorganic Element
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A two-parameter multiple shooting method and its application to the natural vibrations of non-prismatic multi-segment beams
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作者 R.HOŁUBOWSKI K.JARCZEWSKA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2243-2252,共10页
This paper presents an enhanced version of the standard shooting method that enables problems with two unknown parameters to be solved.A novel approach is applied to the analysis of the natural vibrations of Euler-Ber... This paper presents an enhanced version of the standard shooting method that enables problems with two unknown parameters to be solved.A novel approach is applied to the analysis of the natural vibrations of Euler-Bernoulli beams.The proposed algorithm,named as two-parameter multiple shooting method,is a new powerful numerical tool for calculating the natural frequencies and modes of multi-segment prismatic and non-prismatic beams with different boundary conditions.The impact of the axial force and additional point masses is also taken into account.Due to the fact that the method is based directly on the fourth-order ordinary differential equation,the structures do not have to be divided into many small elements to obtain an accurate enough solution,even though the geometry is very complex.To verify the proposed method,three different examples are considered,i.e.,a three-segment non-prismatic beam,a prismatic column subject to non-uniformly distributed compressive loads,and a two-segment beam with an additional point mass.Numerical analyses are carried out with the software MATHEMATICA.The results are compared with the solutions computed by the commercial finite element program SOFiSTiK.Good agreement is achieved,which confirms the correctness and high effectiveness of the formulated algorithm. 展开更多
关键词 two-parameter multiple shooting method two-point boundary value problem natural vibration non-prismatic beam multi-segment beam
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Efficient Decomposition Shooting Method for Solving Third-Order Boundary Value Problems
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作者 Nawal Al-Zaid Kholoud Alzahrani +1 位作者 Huda Bakodah Mariam Al-Mazmumy 《International Journal of Modern Nonlinear Theory and Application》 2023年第3期81-98,共18页
The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and... The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and, the modified shooting method. A complete derivation of the proposed method has been provided, in addition to its numerical implementation and, validation via the utilization of the Runge-Kutta method and, other existing methods. The method has been applied to diverse test problems and turned out to perform remarkably. Lastly, the simulated numerical results have been graphically illustrated and, also supported by some absolute error comparison tables. 展开更多
关键词 Linear Third Order BVPs shooting Method Adomian Decomposition Method Two-Point Boundary Value Problem
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机械工程trouble-shooting案例分析教学与动手能力培养
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作者 朱派龙 战祥乐 《广东轻工职业技术学院学报》 2005年第1期38-41,共4页
通过trouble shooting案例的分析、讨论、实例讲解,力图引导、启发和培养学生在实际工作中如何去发现问题、如何对已有知识、经验、技能的灵活处理和技术知识的转移、搬迁、嫁接、变异、变通和改进等方面的技巧和动手能力,目的是使学生... 通过trouble shooting案例的分析、讨论、实例讲解,力图引导、启发和培养学生在实际工作中如何去发现问题、如何对已有知识、经验、技能的灵活处理和技术知识的转移、搬迁、嫁接、变异、变通和改进等方面的技巧和动手能力,目的是使学生学习达到“鱼”、“渔”共获。 展开更多
关键词 机械工程 动手能力 trouble-shooting案例分析 教学内容
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Shoot译名之我见
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作者 王孟本 《科技术语研究》 2001年第3期25-26,共2页
关键词 shoot 译名 植物学 英语 翻译
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如何看待shoot一词的中文译名
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作者 李正理 《科技术语研究》 2001年第3期23-25,共3页
关键词 shoot 中文译名 植物学 翻译 英语
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Establishing Submersed Macrophytes via Sinking and Colonization of Shoot Fragments Clipped off Manually 被引量:8
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作者 WU Zhenbin ZUO Jincheng +3 位作者 MA Jianmin WU Juan CHENG Shuiping LIANG Wei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期553-557,共5页
In this paper, sinking and growth of apexes and mid-stems of Myriophyllum spicatum L., Hydrilla verticillata (L.f.) Royle and Ceratophyllum demersum L. in concrete ponds containing eutrophic water and sediment were ... In this paper, sinking and growth of apexes and mid-stems of Myriophyllum spicatum L., Hydrilla verticillata (L.f.) Royle and Ceratophyllum demersum L. in concrete ponds containing eutrophic water and sediment were investigated. Sinking rates of apexes and mid-stems reached 34.8% and 4.4% at the 6 th day and 91.1% and 66.7% at the 22 nd day for M. spicatum, 57.8% and 55.6% at the 6 th day and 100% and 97.8% at the 22 nd day for H. vertieillata, 18.9% and 86.7% at the 6 th day and 95.6% and 100% at the 22 nd day for C. demersum, respectively. Most sunken fragments established themselves successfully with significant growth. Total shoot length ofplantlets developed from apexes and mid-stems increased by 399% and 61% for M. spicatum, 593% and 256% for H. vertieillata and 114% and 104% for C. demersum, respectively. The results showed that it was feasible to establish submersed macrophytes via sinking and colonization of shoot fragments clipped off manually. 展开更多
关键词 EUTROPHICATION submersed macrophyte restoration shoot fragment SINK establish
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Standardization of harvesting age of bamboo shoots with respect to nutritional and anti-nutritional components 被引量:6
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作者 Ashok K. Pandey Vijayalakshmi Ojha 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期83-90,共8页
Bamboo shoots can be harvested at different ages but the data on the changes in nutritional composition with age are scanty. We standardized harvesting age of bamboo shoots in central India to obtain best quality prod... Bamboo shoots can be harvested at different ages but the data on the changes in nutritional composition with age are scanty. We standardized harvesting age of bamboo shoots in central India to obtain best quality produce with respect to nutritional composition. The shoots harvested on different days (2–20 days after emergence from ground) were analyzed for their nutritional (dietary fibres, carbohydrates, proteins, total phenols, ascorbic acid, sodium, potassium, phosphorus, calcium, magnesium and phenolic acids) and anti nutritional (cyanogen) constituents. A significant variation (at p ≤ 0.5) was observed in the nutritional composition of shoots of Dendrocalamus asper, D. strictus and Bambusa tulda harvested at different days. An overall decrease was observed in proteins and total phenols while dietary fibres and carbohydrates increased with ages. Significant variation (at p ≤ 0.5) was also observed in phenolic acids while minerals did not vary significantly. Results revealed that the optimum harvesting age for D. asper, D. strictus and B. tulda was on 10–14 days, 6–10 days and 10–16 days (after emergence from the ground) respectively. These results can be used to obtain quality bamboo shoots. 展开更多
关键词 Bamboo shoots HARVESTING nutritional status central India phenolic acids anti-nutrient
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Does the root to shoot ratio show a hormetic response to stress? An ecological and environmental perspective 被引量:5
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作者 Evgenios Agathokleous Regina G.Belz +2 位作者 Mitsutoshi Kitao Takayoshi Koike Edward J.Calabrese 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1569-1580,共12页
Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ra... Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ratio has been discussed in the context of ecological theory and its potential importance in ecological succession,where species follow different strategies for above-ground growth for light or below-ground competition for water and nutrients.We present evidence showing the R/S ratio follows a biphasic dose–response relationship under stress,typical of hormesis.The R/S ratio in response to stress has been widely compared among species and ecological succession classes.It is constrained by a variety of factors such as ontogeny.Furthermore,the current literature lacks dose-response studies incorporating the full dose–response continuum,hence limiting scientific understanding and possible valuable application.The data presented provide an important perspective for new-generation studies that can advance current ecological understanding and improve carbon storage estimates by R/S ratio considerations.Hormetic response of the R/S ratio can have an important role in forestry for producing seedlings with desired characteristics to achieve maximum health/productivity and resilience under plantation conditions. 展开更多
关键词 Biological plasticity Biphasic RESPONSE HORMESIS Plant STRESS Root/shoot RATIO
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Effects of UV-B treatment on controlling lignification and quality of bamboo (Phyllostachys prominens) shoots without sheaths during cold storage 被引量:7
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作者 ZHENG Jian LI Sheng-e +3 位作者 Maratab ALI HUANG Qi-hui ZHNEG Xiao-lin PANG Lin-jiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第5期1387-1395,共9页
For evaluating the effects of UV-B treatment on lignification and quality of bamboo(Phyllostachys prominens) shoots during postharvest, fresh bamboo shoots without sheaths were irradiated with UV-B at a dose of 8.0 kJ... For evaluating the effects of UV-B treatment on lignification and quality of bamboo(Phyllostachys prominens) shoots during postharvest, fresh bamboo shoots without sheaths were irradiated with UV-B at a dose of 8.0 kJ m^(–2) and then stored at(6±1)℃ along with 85–90% relative humidity(RH) for 15 d. The results showed that UV-B treatment apparently slowed down the increase rates of flesh firmness, weight loss, and contents of cellulose and lignin. It also decreased the activities of 4-coumarate CoA ligase(4CL), peroxidase(POD), cinnamyl alcohol dehydrogenase(CAD) and phenylalanine ammonialyase(PAL) and the expression of their encoding genes during cold storage. It was suggested that these effects of UV-B treatment on decreases in these enzymatic activities and the expression of encoding genes might collectively regulate lignin synthesis and accumulation in the flesh of bamboo shoots and consequently benefit in maintaining the edible quality of bamboo shoots during cold storage. 展开更多
关键词 BAMBOO shoot LIGNIFICATION QUALITY UV-B TREATMENT cold storage
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Influence of core box vents distribution on flow dynamics of core shooting process based on experiment and numerical simulation 被引量:4
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作者 Chang-jiang Ni Gao-chun Lu +4 位作者 Qing-dong Zhang Tao Jing Jun-jiao Wu Lin-long Yang Qin-fang Wu 《China Foundry》 SCIE 2016年第1期22-29,共8页
Core shooting process plays a decisive role in the quality of sand cores, and core box vents distribution is one of the most important factor determining the effectiveness of core shooting process. In this paper, the ... Core shooting process plays a decisive role in the quality of sand cores, and core box vents distribution is one of the most important factor determining the effectiveness of core shooting process. In this paper, the influence of core box vents distribution on the flow dynamics of core shooting process was investigated based on in situ experimental observations with transparent core box, high-speed camera and pressure measuring system. Attention was focused on the variation of both the flow behavior of sand and pressure curves due to different vents distribution. Taking both kinetic and frictional stress into account, a kinetic-frictional constitutive model was established to describe the internal momentum transfer in the solid phase. Two-fluid model(TFM) simulation was then performed and good agreement was achieved between the experimental and simulated results on both the flow behavior of sand and the pressure curves. It was found that vents distribution has direct effect on the pressure difference of different locations in the core box, which determines the buoyancy force exerting on the sand particles and significantly influences the filling process of core sand. 展开更多
关键词 vents distribution flow dynamics pressure variation core shooting process kinetic-frictional model two-fluid model
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Algorithm on robot soccer pass and shoot a ball 被引量:5
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作者 李建伟 洪炳熔 杨艳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第3期293-295,共3页
Introduces of robot soccer’s competition software of Harbin Institute of Technology (HIT), the concept of running range and the method of calculating the running range for both the opponent and our teammates accordin... Introduces of robot soccer’s competition software of Harbin Institute of Technology (HIT), the concept of running range and the method of calculating the running range for both the opponent and our teammates according to the distances between the ball and robot soccers, and therefore the method of calculating the angle that the robot passes or shoots the ball according to the running ranges of both sides. And gives the examples of passing the ball when the ball’s position is in the backcourt and shooting the ball when the ball’s position is in the frontcourt. 展开更多
关键词 robot soccer running range passing a ball shooting a ball
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One Rapid and Efficient Method for Isolation of Total RNA from Shoots Regenerated in vitro of Populus suaveolens 被引量:5
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作者 LinYuanzhen LinShanzhi ZhangZhiyi HeChengzhong GuoHuan ZhangWei 《Forestry Studies in China》 CAS 2004年第1期18-21,共4页
关键词 Populus suaveolens shoots regenerated in vitro RNA ISOLATION
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Assessment of factors affecting in vitro shoot regeneration from axillary bud explant of Camptotheca acuminata 被引量:3
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作者 WANGHui-Mei ZUYuan-Gang DONGFeng-Li ZHAOXiao-Ju 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期52-54,i003,共4页
Axillary buds from 3-yr.-old seedlings of Camptotheca acuminata in the greenhouse were cultured on the different basal media with different concentrations of growth regulators for shoot regeneration for studying the e... Axillary buds from 3-yr.-old seedlings of Camptotheca acuminata in the greenhouse were cultured on the different basal media with different concentrations of growth regulators for shoot regeneration for studying the effects of different basal media, different concen- trations of growth regulators (BA or TDZ), sucrose, agar and pH value on shoot regeneration from axillary bud. The results showed that B5 and WPM media were the optimal basal media and the optimal phyotohormone was BA of 1.0 mg/L or TDZ of 0.1mg/L; The concentrations of sucrose of 30g/L and agar of 6g/L were most suitable for the shoot regeneration; pH value from 5.8 to 6.6 were broadly effective, but the best at pH 5.8. 展开更多
关键词 Camptotheca acuminata Axillary bud shoot regeneration Growth regulators Basal media
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Cell Ultrastructure of Kiwifruit (Actinidia chinensis) Shoot Tips During Cryopreservation 被引量:3
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作者 XU Xiao-biao CAI Zi-guo +1 位作者 GU Qing-qing ZHANG Qiu-ming 《Agricultural Sciences in China》 CAS CSCD 2006年第8期587-590,共4页
The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit (Actinidia chinensis Ganmi 5) during cryopreservation were investigated. Shoot tips were preserved in liquid ni... The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit (Actinidia chinensis Ganmi 5) during cryopreservation were investigated. Shoot tips were preserved in liquid nitrogen using vitrification, and the cell ultrastructure was examined using transmission electron microscopy (TEM). The regular ultrastructure of the cell wall, cell membrane and nucleus of shoot tips could be damaged during the freezing and thawing associated with preservation using liquid nitrogen. The cell plasmolysis was increased and freezing tolerance was improved after precultufing and dehydrating in a preservation and vitrification solution (PVS2) (30% glycerol (Gly)+ 15% ethylene glycol (EG)+ 15% dimethylsulfoxide (DMSO) + 0.4 mol L^-1 sucrose). The structure of some cells with low degree of injury and reversible damage was similar to that of the control and they could undergo normal cell division and differentiation. Besides, they could recover automatically and regenerate after their reculture. 展开更多
关键词 CRYOPRESERVATION VITRIFICATION shoot tips ULTRASTRUCTURE KIWIFRUIT
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Virulence and mycotoxic effects of Metarhizium anisopliae on Mahogany shoot borer,Hypsipyla robusta(Lepidoptera:Pyralidae) 被引量:4
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作者 M.Balachander O.K.Remadevi +1 位作者 T.O Sasidharan N.Sapna Bai 《Journal of Forestry Research》 CAS CSCD 2012年第4期651-659,共9页
Developing appropriate control measures for the Mahogany shoot borer, Hypsipyla robusta Moore has become increasingly important due to the severe damaging effect of the pest on the establishment of the saplings of Swi... Developing appropriate control measures for the Mahogany shoot borer, Hypsipyla robusta Moore has become increasingly important due to the severe damaging effect of the pest on the establishment of the saplings of Swietenia mahagoni Jacq (Sapindales: Meliaceae). Existing management methods are largely limited to silvicultural practices and spraying of chemical insecticides. To identify a potential fungal biocontrol agent, we compared the virulence of six native and two standard ARSEF isolates of Metarhizium anisopliae Metsch. against this pest. The average survival time and conidial yield of IWST-Ma7 was higher (6.2 to 7.3 days and 4.9 to 4.7 x 105 conidia/ml) than the standards. Sig- nificant difference in sporulation on the cadavers between isolates, doses and incubation periods were substantiated for the selection of potential strain. The mycotoxic effects of crude soluble protein extract when in- corporated in the artificial diet, the ARSEF 2596 and ARSEF 3603 showed LDs0 value of 3.7% and 5.6%. However, IWST-Ma7 was highly lethal with significant lowest LDs0 value of 2.6%. The enzyme activity of IWST-Ma7 was highest for chitinase, CDA, protease and lipase viz., 1.90 U/mg, 1.80 U/mg, 0.98 U/mg and 0.80 U/mg respectively. However the enzyme activity of chitinase and Chitin deacetylase assay for all the isolates was significantly higher than protease and lipase activity. The ITS regions (5.8S rDNA and 28S rDNA) of seven isolates of M. anisopliae were amplified using the ITS1 and ITS4 primers which was a unique fragment of approximately 550 bp. Based on ITS regions, phy- logenetic tree have been constructed and the isolates have been grouped in to 5 clades. The virulence and mycotoxic effects of different isolates could rationally be used to employ them for the management of the mahogany borer. 展开更多
关键词 Metarhizium anisopliae MYCOTOXIN mahogany shoot borer Hypsipyla robusta
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Regulation of phytohormones on root primordium initiation and adventitious root formation in the etiolated shoots of Paeonia suffruticosa'Yinfen Jinlin' 被引量:4
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作者 Zeng Duan-xiang Yin Wei-lun +1 位作者 Zhao Xiao-qing Wang Hua-fang 《Forestry Studies in China》 CAS 2006年第4期87-91,共5页
Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles ... Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstructures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated soft- wood shoots of Paeonia suffkuticosa 'Yinfen Jinlin'. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages: shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protru- sion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043 nmol·g^-1 FW on the bases of shoots, respectively. CTKs which included isopentenyl adenine (iPA), zeatin riboside (ZR) and dihy- drozeatin riboside (DHZR) were 0.949, 0.695 and 2.034 nmol·g^-1 FW, respectively. DHZR is active among CTKs. The ratio of IAA to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primor- dium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. ]AA levels in the treated shoots increased gradually to its highest level (three times of control) at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10:1. 展开更多
关键词 tree peony (Paeonia suffruticosa‘Yinfen Jinlin') etiolated shoot PHYTOHORMONES PRIMORDIUM adventitious root
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In vitro germination and shoot proliferation of the threatened species Cinchona officinalis L(Rubiaceae). 被引量:2
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作者 Rosa Armijos-Gonzalez Cesar Perez-Ruiz 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第6期1229-1236,共8页
Cinchona officinalis (Rubiaceae) is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosyst... Cinchona officinalis (Rubiaceae) is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosystem, C. officinalis populations are threatened. Currently, natural regeneration of the populations is low, despite its high plant regeneration and seed formation capacity. In the present study, an efficient protocol for germination, shoot proliferation and plantlets regeneration was developed for this species. Phenolic content and germination rate of C. officinalis seeds were compared with a control species, C. pubescens. Nodal segments from seedlings of C. officinalis were cultured on Gamborg medium supplemented with different combinations of plant growth regulators. Because the phenol content is high in C. officinalis, the phenolic should be removed with hydrogen peroxide or water washes to stimulate germination. Shoots and callus developed from nodal segments within 45 days using most of the tested combinations of plant growth regulators. The best rates of shoot proliferation, callus formation and adventitious buds were obtained in medium supplemented with 5.0 mg L^-1 6-benzyl-aminopurine and 3.0 mg L^-1 indole- 3-butyfic acid. 展开更多
关键词 CALLUS Cinchona officinalis Germination PHENOLS RUBIACEAE shoot
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