检索结果-南通市图书馆

Design of multi-section luffing apple pruning equipment and cutting test of the key components

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 109-117页

作者： Siyuan Tong Wenbin Li Yaxiong Wang Lei Zhang Feng Kang School of Technology Beijing Forestry UniversityKey Lab of State Forestry and Grassland Administration for Forestry Equipment and AutomationBeijing 100083China

In order to reduce the labor intensity and improve the efficiency of pruning,this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of China.In the essay,the structure and working principle of the equipment are expounded,the cutter was analyzed,and the parameters were determined.Using the self-made test bench to simulate the field experiment,this study selected the ratio of cutting speed to feeding speed and feeding speed as the influencing factors and took the cut-off rate,cutting efficiency and cutting power as the objectives to carry out single factor experiment and quadratic regression orthogonal experiment.The test results show that the cutting power increases with the increase of ratio of cutting speed to feeding speed,and the cut-off rate and cutting efficiency first increase and then decrease.As the feeding speed increases,the cutting efficiency and power increase,and the cut-off rate decreases.When the cutoff rate was greater than 80%,the optimal combination of operating parameters was the feeding speed of 0.55 m/s and ratio of cutting speed to feeding speed of 1.29.Under this combination,the cut-off rate was 84.9%,the cutting efficiency was 13.1,and the cutting power was 175.7 W.The error between the predicted target value of the model and the average measured target value was less than 7%,so the test results are reliable.According to the obtained optimal operating parameters,the actual cutting experiment of the pruning equipment in the field was carried out,and the cutting rate was 96.3%,which meet the design requirements.This study can also meet the needs of mechanized pruning of fruit trees with different crown shapes,improve the applicability of pruning equipment,and provide support for the development of mechanized pruning equipment in China.

关键词： apple pruning equipment cutting test optimal parameters regression analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Development and parentage analysis of SNP markers for Chestnut-vented Nuthatch(Sitta nagaensis)based on ddRAD-seq data

引用

Avian Research 2024年第2期15卷 271-278页

作者： Qingmiao Yuan Xi Lu Ruixin Mo Xianyin Xu Xu Luo Yubao Duan Key Laboratory for Conserving Wildlife with Small Populations in yunnan Southwest Forestry UniversityKunming 650224China Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunming 650224China Key Laboratory of Forest Disaster Warning and Control of yunnan Province Southwest Forestry UniversityKunming 650224China College of forestry Southwest Forestry UniversityKunming 650224China Administration of Zixi Mountain provincial Nature Reserve Chuxiong 675008China

Extra-pair paternity(EPP)is commonly found in socially monogamous birds,especially in small passerine birds,and there are interspecific and intraspecific variations in the extent of EPP.The Chestnut-vented Nuthatch(Sitta nagaensis)is a socially monogamous passerine bird,and verifying whether this species has EPP relies on parentage testing-S.nagaensis is not known to have EPP.In this study,we developed SNP markers of this species that are informative for parentage analysis from double digest restriction site-associated DNA sequencing(ddRAD-seq)data.A panel consisting of 50 SNP markers,with a mean heterozygosity of 0.343,was used to resolve 95% of nestlings to fathers.The combined exclusion probabilities for the first parent and second parent were 0.991 and 0.9999,respectively.This panel of SNP markers is a powerful tool for parentage assignments in S.nagaensis.In addition,we found that three offspring(7.9%)from three nests(23.1%)were the result of extra-pair fertilization out of 38 offspring in 13 nests.Our study provided information on parentage analysis that has not been reported before in S.nagaensis.It also supplemented the understudied EPP behavior of birds in Asia,contributing to a general understanding of the EPP behaviors of birds.

关键词： Chestnut-vented Nuthatch ddRAD sequencing Extra-pair paternity Parentage analysis SNPs

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Preparation and gastrointestinal release characteristics of zein / Houttuynia cordata flavonoids composite nanoparticles

引用

Jingxi Huagong/Fine Chemicals 2024年第6期41卷 1345-1353and1361页

作者： Jiang Y. Fan F. Chen C. Sun X. Liu J. College of Life Science Southwest Forestry University Yunnan Kunming 650224 China Key Laboratory of National forestry and grassland Administration on Biodiversity Conservation in Southwest China Yunnan Kunming 650224 China Key Laboratory of Forest Disaster Warning and Control of yunnan Province Yunnan Kunming 650224 China College of forestry Southwest Forestry University Yunnan Kunming 650224 China

In order to improve the stability of Houttuynia cordata flavonoids (HCF), Zein/HCF composite nanoparticles were synthesized from zein (Zein) and HCF by anti-solvent method and characterized for structural analysis. The effects of zein and HCF mass ratio on the composite nanoparticles were further investigated. The results showed that there were intermolecular forces, including hydrogen bonding, hydrophobic and electrostatic interactions, between HCF and zein. When m(Zein)∶m(HCF)=20∶3, Zein/HCF composite nanoparticles exhibited the best performance with the highest melting temperature reaching 85.09 ℃, 12.84 ℃ higher than that of Zein nanoparticles (72.25 ℃), its microstructure uniformly dispersed in a spherical shape with the smallest average particle size and polydispersity index (PDI), the narrowest particle size distribution, and the largest absolute Zeta potential value as well as HCF encapsulation rate. In addition, the composite nanoparticles exhibited higher 1,1-diphenyl-2-picrylhydrazyl and diammonium 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals scavenging ability, and better heat treatment protection ability by improving the heating stability of HCF. In the simulated gastrointestinal digestion process, the HCF release rate was only 22.31% after 120 min of digestion by simulated gastric fluid (SGF) and reached 75.66% after 120 min of digestion by simulated intestinal fluid (SIF). The HCF release trends in the simulated gastrointestinal fluid were all consistent with the Ritger-Peppas model, but the release mechanisms were different, with a non-Fick diffusion mechanism in SGF while a Fick diffusion mechanism in SIF. © 2024 Fine Chemicals. All rights reserved.

关键词： food chemicals gastrointestinal release characteristics Houttuynia cordata flavonoids nanoparticles zein

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

引用

Journal of forestry Research 2024年第3期35卷 111-130页

作者： Xin Chen Yujun Sun State forestry&grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable information.However,the potential of GEE for forest resource management has not been fully exploited.To extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast China.Spectral and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant species.The results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source independently.Similarly,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was accurate.Including terrain factors and removing spatial correlation from NFRI sample points further improved the recognition accuracy.The optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,respectively.The high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant species.Visualizing the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sclerodermus alternatusi(Hymenoptera: Bethylidae), a new species from China, parasitizing Monochamus alternatus(Coleoptera: Cerambycidae)

引用

Zoological Systematics 2024年第3期 258-266页

作者： Zhongqi Yang Xiaoyi Wang Zhaoyao Duan Yanlong Zhang Yi'nan Zhang Liangming Cao Ke Wei Key Lab of Forest Protection National Forestry and Grassland Administration Ecology and Nature Conservation Institute Chinese Academy of Forestry Research Institute of Forest Protection Yunnan Academy of Forestry and Grassland Research Institute of Biological Control Beijing Vocational College of Agriculture Key Lab of Forest Protection National Forestry and Grassland AdministrationEcology and Nature Conservation Institute Chinese Academy of Forestry

A new species, Sclerodermus alternatusi Yang, sp. nov.(Hymenoptera:Bethylidae),is described and illustrated. Its cerambycid host, Monochamus alternatus Hope, a severe wood borerattackingmanypinetrees(Pinusspp.),isalsoavectorofpinewoodnematode,Bursaphelencusxylophilus,whichcauseseveredamagestopineforestsinChina.Thenew species is a gregarious ectoparasitoid of junior larva of M. alternatus. The number of adult wasps reared from a single host larva ranges from 6 to 45. The ratio of female to male is 20:1. The new parasitoid species has a high potential in using as a biocontrol agent for the wood borer.Diagnosis of the new species with comparisons to its related species, S. pupariae Yang&Yao and a key to known species of Sclerodermus from China is provided.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Spatial-temporal population dynamics of the critically endangered Blue-crowned Laughingthrush Pterorhinus courtoisi:a 22-year longitudinal study

引用

Science China Life Sciences 2024年第8期 1769-1771页

作者： Tao Liu Jutao He Chang Xiao Jie Liu Jie Sun Minling Li Yuanhua Hong Weiwei Zhang Fuwen Wei Jiangxi provincial Key Laboratory of Conservation Biology Jiangxi Agricultural University forestry bureau of Wuyuan

Dear Editor,Population size is a crucial indicator in evaluating the conservation status of a species.Understanding the patterns of population fluctuation and the distribution range of endangered species is important for biodiversity conservation,which contributes to ecosystem functioning(Li et al.,2019;Eisenhauer,2022).

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

More tree growth reduction due to consecutive drought and its legacy effect for a semiarid larch plantation in Northwest China

引用

Journal of forestry Research 2024年第2期35卷 188-196页

作者： Yanfang Wan Pengtao Yu Yanhui Wang Jiamei Li Yushi Bai Yipeng Yu Bingbing Liu Xiaocha Wei Key Laboratory of Forest Ecology and Environment of National forestry and grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China

Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate warming.In this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch plantation.We found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry years.Our results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry years.Our results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas.

关键词： Tree rings Drought effects Legacy effects Growth-climate relationships Larix principis-rupprechtii

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Identification of Phenylalanine Ammonia-Lyase(PAL)Genes from Pinus yunnanensis and an Analysis of Enzyme Activity in vitro

引用

Phyton-International Journal of Experimental Botany 2024年第3期93卷 503-516页

作者： Dejin Mu Lin Chen Heze Wang Zhaoliu Hu Sihui Chen Shi Chen Nianhui Cai Yulan Xu Junrong Tang Key Laboratory of National forestry and grassland Administration on Biodiversity Conservation in Southwest China Southwest Forestry UniversityKunming650224China College of forestry Southwest Forestry UniversityKunming650224China

Phenylalanine ammonia lyase(PAL)is the rate-limiting and pivotal enzyme of the general phenylpropanoid path-way,but few reports have been found on PAL genes in Pinus yunnanensis.In the present study,three PAL genes were cloned and identiﬁed from P.yunnanensis seedlings for theﬁrst time,namely,PyPAL-1,PyPAL-2,and PyPAL-3.Our results indicated that the open-reading frames of PyPAL genes were 2184,2157,and 2385 bp.Phylogenetic tree analysis revealed that PyPALs have high homology with other known PAL genes in other plants.In vitro enzymatic analysis showed that all three PyPAL recombinant proteins could catalyze the deamination of L-phenylalanine to form trans-cinnamic acid,but only PAL1 and PAL2 can catalyze the conversion of L-tyrosine toρ-coumaric acid.Three PyPAL genes were expressed in different tissues in 1-year-old P.yunnanensis,and such genes had different expression patterns.This study lays a foundation for further understanding of the biosynthesis of secondary metabolites in P.yunnanensis.

关键词： Pinus yunnanensis phenylalanine ammonia-lyase enzyme activity in vitro functional analysis secondary metabolites

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chromosomal-level genome and metabolome analyses of highly heterozygous allohexaploid Dendrocalamus brandisii elucidate shoot quality and developmental characteristics

引用

Journal of Integrative Plant Biology 2024年第6期66卷 1087-1105页

作者： Jutang Jiang Zeyu Zhang Yucong Bai Xiaojing Wang Yuping Dou Ruiman Geng Chongyang Wu Hangxiao Zhang Cunfu Lu Lianfeng Gu Jian Gao Key Laboratory of National forestry and grassland Administration Beijing for Bamboo & Rattan Science and Technology Institute of Gene Science and Industrialization for Bamboo and Rattan Resources International Center for Bamboo and Rattan College of forestry Basic Forestry and Proteomics Research Center Fujian Agriculture and Forestry University School of Life Science Peking University College of Biological Sciences and Biotechnology Beijing Forestry University

Dendrocalamus brandisii(Munro) Kurz is a sympodial bamboo species with inimitable taste and flavorful shoots. Its rapid growth and use as high-quality material make this bamboo species highly valued for both food processing and wood applications. However, genome information for D. brandisii is lacking, primarily due to its polyploidy and large genome size.Here, we assembled a high-quality genome for hexaploid D. brandisii, which comprises 70chromosomes with a total size of 2,756 Mb,using long-read Hi Fi sequencing. Furthermore,we accurately separated the genome into its three constituent subgenomes. We used Oxford Nanopore Technologies long reads to construct a transcriptomic dataset covering 15 tissues for gene annotation to complement our genome assembly, revealing differential gene expression and post-transcriptional regulation. By integrating metabolome analysis, we unveiled that well-balanced lignin formation, as well as abundant flavonoid and fructose contents,contribute to the superior quality of D. brandisii shoots. Integrating genomic, transcriptomic,and metabolomic datasets provided a solid foundation for enhancing bamboo shoot quality and developing efficient gene-editing techniques. This study should facilitate research on D. brandisii and enhance its use as a food source and wood material by providing crucial genomic resources.

关键词： bamboo shoots Dendrocalamus brandisii (Munro) Kurz flavonoid genome lignin

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Abiotic stress treatment reveals expansin like A gene OfEXLA1 improving salt and drought tolerance of Osmanthus fragrans by responding to abscisic acid

引用

Horticultural Plant Journal 2024年第2期10卷 573-585页

作者： Bin Dong Qianqian Wang Dan Zhou Yiguang Wang Yunfeng Miao Shiwei Zhong Qiu Fang Liyuan Yang Zhen Xiao Hongbo Zhao School of Landscape Architecture Zhejiang Agriculture and Forestry UniversityHangzhouZhejiang 311300China Zhejiang provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants HangzhouZhejiang 311300China Key Laboratory of National forestry and grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants HangzhouZhejiang 311300China

Sweet osmanthus(Osmanthus fragrans) is a having general approval aromatic tree in China that is widely applied to landscaping and gardening. However, the evergreen tree adaptability is limited by many environmental stresses. Currently, limited information is available regarding the genetic analysis and functional identification of expansin genes in response to abiotic stress in sweet osmanthus. In this study, a total of 29 expansin genes were identified and divided into four groups by genome-wide analysis from the sweet osmanthus genome. Transcriptome and quantitative Real-time PCR analysis showed that the cell wall-localized protein expansin-like A(OfEXLA1) gene was significantly induced by salt and drought treatment. Histochemical GUS staining of transgenic Arabidopsis lines in which GUS activity was driven with the OfEXLA1 promoter, GUS activity was significantly induced by salt, drought, and exogenous abscisic acid(ABA). In yeast, we found OfEXLA1overexpression significantly improved the population of cells compared with wild-type strains after NaCl and polyethylene glycol(PEG)treatment. Additionally, OfEXLA1 overexpression not only promoted plant growth, but also improved the salt and drought tolerance in Arabidopsis. To gain insight into the role of ABA signaling in the regulation of OfEXLA1 improving abiotic tolerance in sweet osmanthus, four differentially expressed ABA Insensitive 5(ABI5)-like genes(OfABL4, OfABL5, OfABL7, and OfABL8) were identified from transcriptome, and dualluciferase(dual-LUC) and yeast one hybrid(Y1H) assay showed that OfABL4 and OfABL5 might bind to OfEXLA1 promoter to accumulate the OfEXLA1 expression by responding to ABA signaling to improve abiotic tolerance in sweet osmanthus. These results provide the information for understanding the molecular functions of expansin-like A gene and molecular breeding of sweet osmanthus in future.

关键词： Osmanthus fragrans Abiotic tolerance Expansin Abscisic acid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：