The vertical distribution pattern and seasonal dynamics of fine root parameters for the apple trees of different ages （3, 10, 15, and 20 years old） on the Loess Plateau of China were studied. Soil coring method was ...The vertical distribution pattern and seasonal dynamics of fine root parameters for the apple trees of different ages （3, 10, 15, and 20 years old） on the Loess Plateau of China were studied. Soil coring method was used to determine the vertical distribution and seasonal dynamics of fine roots at different root radial distances （1.0, 1.5, and 2.0 m from the main tree trunk）. The fine root biomass density （FRD）, fine root length density （RLD）, and specific root length （SRL）, as well as soil water content and soil temperature were also measured. The FRD and RLD for the 10, 15, and 20 years old trees reached peak values in the 20-30 cm soil layer. For the 3 years old tree, the highest FRD and RLD were observed in the 10-20 cm soil layer. The FRD and RLD decreased with increased soil depth from the 10-20 or 20-30 cm soil layer for all age apple trees. The SRL declined with the increase of tree age. The FRD at the 1.0 m radial distance from the main tree trunk was higher than that at other radial distances in the 3 and 10 years old orchard. However, in the 15 and 20 years old orchards, especially the 20 years old orchard, the FRD at the 2.0 m radial distance was nearly equal to or higher than that at the 1.0 and 1.5 m radial distances. For all the root radiuses or the tree ages, the FRD, RLD, and SRL were the highest in spring and the lowest in autumn. The age of an apple tree does not affect the vertical distribution pattern but the biomass of fine roots and the SRL. Radial distance affects the root horizontal distribution of 3 and 10 years old trees but the 15 and 20 years old trees. Additionally, effects of soil temperature and soil moisture on fine root distribution or seasonal dynamics are not significant.展开更多
Six-year old apple trees were selected for field experiment.The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards.There were three factors:the buried ...Six-year old apple trees were selected for field experiment.The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards.There were three factors:the buried depth H(25,40,55 cm),the horizontal distance L(30,40,60 cm)between the emitters and the trunk of the experimental tree,and the number of the irrigation emitters N(1,2,4).The effect of the arrangement of surge-root irrigation emitters on the growth,yield and irrigation water use efficiency(IWUE)of apple trees were studied in Northern Shaanxi where the irrigation quota takes 60%-75%of the field water capacity.The results showed that the arrangement of emitters for surge-root irrigation had a significant effect on apple tree yield and IWUE,especially,the yield and IWUE reached 28388.17 kg/hm2 and 16.83 kg/m3 in treatment T3,respectively.At the same L and N levels(T1,T2,and T3),the yield and IWUE in treatment T3 were the highest,and the yields in treatments T1 and T2 were decreased by 26.22%and 31.48%,while IWUE is reduced by14.02%and 18.12%compared with T3,respectively.At the same H and N levels(T3,T4,and T5),the yield and IWUE of apple trees were decreased with increasing L level.Especially,when L was 30 cm(T3),the yield and IWUE were the highest.The same L and H levels(T3,T6,and T7)could promote the growth of apple trees when N was 2(T3).Compared with treatment T3,it was found that the increment of new shoots was decreased by 8.07%-18.71%,and the fruit diameter was decreased by 5.41%-9.11%.Therefore,two emitters should be arranged symmetrically on both sides of an apple tree,each was buried at a 40 cm depth and 30 cm away from the trunk of the tree to effectively improve the yield and IWUE of the apple tree in mountainous areas in Northern Shaanxi.展开更多
Red Fuji apple trees of Zn-deficiency were used as material in the experiment. The effect of different Zn application methods on the regularity of Zn transportation and nutrition was studied. It was found that the sto...Red Fuji apple trees of Zn-deficiency were used as material in the experiment. The effect of different Zn application methods on the regularity of Zn transportation and nutrition was studied. It was found that the storage of Zn in the branches was greatly increased by foliar application of the solution of 15% ZnSO4·7H2O before abscission. It had advantage to keep suitable Zn content in leaves, branches and roots, as well as between Zn and P and K, which increased Zn transportation and reusability. Zn content in roots increased when Zn was used in soil in autumn. However, the absorbed Zn did not transport to the top of the plant. It was used by the plant next year. Foliar application of ZnSO4·7H2O at early stage of the plant growth enhanced Zn content of the branch. However, the effect was kept for a short time. It had little effect on Zn transportation when Zn was sprayed three weeks after blossoming.展开更多
The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) duri...The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) during soil drought stress. ABA concentration in drought stressed leafless trees increased significantly compared to the controls. ABA both in roots and xylem rose steadily in the earlier drought stage, reaching a maximum of 1.46±0.35 nmol g\+\{ 1\}FW and 117 nmol l\+\{-1\} after the 8th day. Similar change patterns of ABA concentration was observed in the leafy trees during soil drought stress; ABA concentrations in roots and xylem sap increased and reached the maximum in the first three days; after 8th day , it decreased slightly, whereas leaf ABA concentration increased steadily in drought stressed plants throughout the duration of the experiment. Between drought stressed and control trees, no significant differences were observed in concentration of ZR and DHZR in both leafless and leafy trees; whereas iPA concentration of the drought stressed leafless and leafy plants decreased markedly in the later stage of drought. These results showed that endogenous ABA originated mainly from the roots in the earlier drought stage, and mainly from the leaves in the later drought stage. Total CTK showed no reduction in the earlier drought stage and decreased in the later drought stage.展开更多
Method: Use Multiple Scattering Correction to eliminate the interference of scattering on spectrum in the process of field measurement so as to improve the accuracy of prediction model of tree canopy nitrogen content....Method: Use Multiple Scattering Correction to eliminate the interference of scattering on spectrum in the process of field measurement so as to improve the accuracy of prediction model of tree canopy nitrogen content. Apple trees in Qixia of Yantai City were taken as the test material. The spectral reflectivity of apple tree canopy went through the First Derivative (FD) and Multiple Scattering Correction (MSC) plus first derivative, respectively. The correlation coefficients were calculated between spectral reflectivity and nitrogen content. The Support Vector Machine (SVM) method was used to establish the prediction model. The result indicates that the MSC pre-processing can improve the correlation between spectral reflectivity and nitrogen content. The SVM model with MSC + FD pre-processing was a good way to predict the nitrogen content. The calibration R<sup>2</sup> of the model was 0.746;the validation R2 was 0.720;and its RMSE was 0.452 g·kgˉ<sup>1</sup>. MSC can commendably eliminate scattering error to improve the prediction accuracy of prediction model.展开更多
The nutrient inversion model of apple leaves was established by spectral analysis technology to provide technical support for the fine management of apple trees.In Shuangquan Town,Changqing District,Jinan City,Shandon...The nutrient inversion model of apple leaves was established by spectral analysis technology to provide technical support for the fine management of apple trees.In Shuangquan Town,Changqing District,Jinan City,Shandong Province,the Fuji apple trees with stopping period of spring shoots were taken as research objects.The spectral reflectance and nitrogen content of apple leaves were measured by ASD Field Spec 4 portable ground object spectrometer.Analyzed the correlation between leaf nitrogen content and spectral reflectance.The sensitive wavelengths with high correlation coefficient were select by fractional differential algorithm,and the optimal vegetation index was constructed and screened out.Partial Least Square Regression(PLSR),Support Vector Machine(SVM)and Random Forests(RF)method were used to construct an inversion model of leaf nitrogen content.The results show that the RF model based on fractional differential second-order treatment is the best inversion model for the nitrogen content of leaves during stopping period of spring shoots.The modeling accuracy determination coefficient R2 reached 0.891,RMSE was 0.0841,and RPD was 2.1396.The determination coefficient R2 of the fitting results of the verification set was 0.617,RMSE was 0.1251,and RPD was 1.7105.The inversion model established by RF method is effective in monitoring the nitrogen content in apple leaves,which provides a theoretical basis for monitoring the growth of apple by hyperspectral technology.展开更多
A long time ago,there was a huge apple tree.Alittle boy loved to come and lay around it everyday.He climbed to the tree top,ate the apples,took a napunder the shadow…He loved the tree and the treeloved to play with h...A long time ago,there was a huge apple tree.Alittle boy loved to come and lay around it everyday.He climbed to the tree top,ate the apples,took a napunder the shadow…He loved the tree and the treeloved to play with him. Time went by…The little boy had grown展开更多
At present, with the continuous improvement of China's agricultural construction level, it has objectively driven China's economic development. As a country with a large population, China's agricultural ec...At present, with the continuous improvement of China's agricultural construction level, it has objectively driven China's economic development. As a country with a large population, China's agricultural economy has been an important part of China's economic construction for a long time, and has a vital practical significance. Among them, apple itself is favored by many agricultural growers because of its advantages of good taste, high nutrition and high acceptance by people. However, in the process of apple tree planting, it will be affected by many problems, which requires further management of apple tree planting and pest control to ensure the quality of apple tree planting. Therefore, in order to further improve the cultivation quality of apple trees and do a good job in the cultivation management and pest control of apple trees, this paper mainly aims at the optimization measures of apple tree cultivation management and the pest control technology of apple trees, and puts forward specific feasible methods from various angles, which can provide effective reference for the subsequent work.展开更多
Apple is an important cash crop. Because of its rich nutrition, sweet taste and rich iron, it is an important fruit to improve human immunity. Because the demand for apples in the market is relatively large, high yiel...Apple is an important cash crop. Because of its rich nutrition, sweet taste and rich iron, it is an important fruit to improve human immunity. Because the demand for apples in the market is relatively large, high yield and quality should be considered by growers. When fruit trees are cultivated, the technique of dwarfing and close planting can advance the fruit bearing time of fruit trees and help people to obtain economic benefits. At the same time, it can also make efficient use of the orchard. Therefore, in the cultivation stage, people can use this technology to dwarf the apple trees, effectively control the crown area, increase the single volume and increase the economic benefits. Based on the in-depth analysis of the technical points such as dwarfing dense planting and management, and according to the market demand, the present situation of dwarfing cultivation of fruit trees is analyzed, and the technical points such as scientific land selection, dwarfing rootstocks, density control, crown pruning, water and fertilizer management, orchard clearing and pest prevention are put forward, so as to explore the efficient management technology of apple tree dwarfing culture.展开更多
As a crucial fruit tree crop,the health and yield of apple trees are intricately linked to soil moisture conditions.This study aimed to integrate the enhanced WOFOST model with the HYDRUS model to simulate the growth ...As a crucial fruit tree crop,the health and yield of apple trees are intricately linked to soil moisture conditions.This study aimed to integrate the enhanced WOFOST model with the HYDRUS model to simulate the growth and development of apple trees,as well as the dynamics of soil moisture under varying degrees of water deficit.The outputs of evapotranspiration(ET0)and leaf area index(LAI)from the WOFOST model during the apple growth phase were specifically integrated with HYDRUS-1D.These parameters served as intermediaries to assess the impact of different water deficit scenarios on apple tree growth and soil moisture content.The experimental design included three levels of water deficit treatments in addition to control,with irrigation volumes for the deficit treatments set at 85%,70%,and 55%of the control’s volume,respectively.The model-predicted LAI across all irrigation treatments exhibited an R^(2) range of 0.89-0.95,a normalized root mean square error(NRMSE)between 8.02%and 14.57%,and yield prediction errors ranging from 6.27%to 9.61%,closely aligned with empirical data.The accuracy of simulated soil moisture content was enhanced in the 0-30 cm layer,with a slight decrease in accuracy observed in the 30-60 cm layer.For each irrigation treatment,the R^(2) values for simulated soil moisture content ranged from 0.77 to 0.89 in the 0-30 cm layer and from 0.75 to 0.81 in the 30-60 cm layer.This study validated the capability of the WOFOST-HYDRUS model to accurately simulate the effects of varied water deficit treatments on soil moisture,LAI,and apple tree yield,providing valuable insights for developing optimal irrigation strategies.展开更多
Accurate monitoring and spatial distribution of the leaf chlorophyll content(LCC)and canopy chlorophyll content(CCC)of individual apple trees are highly important for the effective management of individual plants and ...Accurate monitoring and spatial distribution of the leaf chlorophyll content(LCC)and canopy chlorophyll content(CCC)of individual apple trees are highly important for the effective management of individual plants and the promotion of the construction of modern smart orchards.However,the estimation of LCC and CCC is affected by shadows caused by canopy structure and observation geometry.In this study,we resolved the response rela-tionship between individual apple tree crown spectra and shadows through a three-dimensional radiative transfer model(3D RTM)and unmanned aerial vehicle(UAV)multispectral images,assessed the resistance of a series of vegetation indices(VIs)to shadows and developed a hybrid inversion model that is resistant to shadow inter-ference.The results revealed that(1)the proportion of individual tree canopy shadows exhibited a parabolic trend with time,with a minimum occurring at noon.Correspondingly,the reflectance in the visible band decreased with increasing canopy shadow ratio and reached a maximum value at noon,whereas the pattern of change in the reflectance in the near-infrared band was opposite that in the visible band.(2)The accuracy of chlorophyll content estimation varies among different VIs at different canopy shadow ratios.The top five VIs that are most resistant to changes in canopy shadow ratios are the NDVI-RE,Cire,Cigreen,TVI,and GNDVI.(3)For the con-structed 3D RTM+GPR hybrid inversion model,only four VIs,namely,NDVI-RE,Cire,Cigreen,and TVI,need to be input to achieve the best inversion accuracy.(4)Both the LCC and the CCC of individual trees had good validation accuracy(LCC:R^(2)=0.775,RMSE=6.86μg/cm^(2),nRMSE=12.24%;CCC:R^(2)=0.784,RMSE=32.33μg/cm^(2),and nRMSE=14.49%),and their distributions at orchard scales were characterized by considerable spatial heterogeneity.This study provides ideas for investigating the response between individual tree canopy shadows and spectra and offers a new strategy for minimizing the influence of shadow effects on the accurate estimation of chlorophyll content in individual apple trees.展开更多
Nitrogen(N)is an important mineral element in apple production.Rapid estimation of apple tree N status is helpful for achieving precise N management.The objective of this work was to explore partial least squares(PLS)...Nitrogen(N)is an important mineral element in apple production.Rapid estimation of apple tree N status is helpful for achieving precise N management.The objective of this work was to explore partial least squares(PLS)regression in dimensional reduction of spectral data and build the diagnostic model.The spectral reflectance data were collected from Fuji apple trees with 4 levels of N fertilizer treatment in the Loess Plateau in 2018 and 2019 using an ASD portable spectroradiometer,and leaf total N content was obtained at the same time.The raw spectra were pretreated using Savitzky-Golay(SG)smoothing and a combination of SG and first-order derivative(SG_FD)or second-order derivative(SG_SD).The samples were divided into a calibration dataset and a prediction dataset using SPXY.Based on 4 factors of PLS regression,including latent variables(LVs),X-loading,variable importance in projection(VIP)and regression coefficients(RC),the 6 methods(LVs,X-loading,VIP_01,VIP_02,RC_01 and RC_02)were derived and used for variable extraction,based on which PLS model and ELM model were established.The results indicated that the spectral data processed by SG_FD had the highest signal-to-noise ratio and was selected for subsequent analysis.The amounts of variables extracted by LVs,X-loading,VIP_01,VIP_02,RC_01 and RC_02 were 6,11,18,305,26 and 88,respectively.The method of extracting variables with an RC threshold based on the minimum RMSEP(RC_02)could effectively avoid the omission of effective information.The RC_02 method was recommended for related research which required accurate wavelength information as a variable.The variable extraction method based on LVs generated an ELM model with a simple structure.The prediction results showed that the ELM model outperformed the PLS model.The PLS(LVs)_ELM model was the best;R2P,RMSEP and RPD were 0.837,2.393 and 2.220,respectively.展开更多
Water storage pit irrigation is a new method suitable for apple trees.It comes with advantages such as water saving,water retention and drought resistance.A precise study of soil water movement and root water uptake i...Water storage pit irrigation is a new method suitable for apple trees.It comes with advantages such as water saving,water retention and drought resistance.A precise study of soil water movement and root water uptake is essential to analyse and show the advantages of the method.In this study,a mathematical model(WSPI-WR model)for 3D soil water movement and root water uptake under water storage pit irrigation was established based on soil water dynamics and soil moisture and root distributions.Moreover,this model also considers the soil evaporation,pit wall evaporation and water level variation in the pit.The finite element method was used to solve the model,and the law of mass conservation was used to analyse the water level variation.The model was validated by experimental data of the sap flow of apple trees and soil moisture in the orchard.Results showed that the WSPI-WR model is highly accurate in simulating the root water uptake and soil water distributions.The WSPI-WR model can be used to simulate root water uptake and soil water movement under water storage pit irrigation.The simulation showed that orchard soil water content and root water uptake rate centers on the storage pit with an ellipsoid distribution.The maximum distribution region of soil water and root water uptake rate was near the bottom of the pit.Distribution can reduce soil evaporation in the orchard and improve the soil water use efficiency in the middle-deep soil.展开更多
Alternate partial root-zone irrigation(APRI)can improve water use efficiency in arid areas. However,the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use ...Alternate partial root-zone irrigation(APRI)can improve water use efficiency in arid areas. However,the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use have not been reported. A two-year field experiment was conducted with two irrigation amounts(400 and500 mm) and three irrigation methods(conventional irrigation, APRI with high and low frequencies). Root length density, stomatal conductance, photosynthetic rate,transpiration rate, leaf water use efficiency, midday stem and leaf water potentials were measured. The results show that in comparison with conventional irrigation, APRI with high frequency significantly increased root length density and decreased water potentials and stomatal conductance.No differences in the above indicators between the two APRI frequencies were detected. A significantly positive relationship between stomatal conductance and root length density was found under APRI. Overall, alternate partial root-zone irrigation with high frequency has a great potential to promote root growth, expand water uptake capacity and reduce unproductive water loss in the arid apple production area.展开更多
[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close plantin...[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close planting of dwarf rootstock apples.[Method] The technical parameters of individual trees and group parameters as shoot number and composition and canopy coverage were determined, and the light quality in the canopy, fruit production and quality were investigated. [Result] Slender spindle （SS） orchard has 54 thousands shoots per 667 m^2. Coverage rate is 76%. Leaf area index is 1.9. The ratio of long, medium and spur shoots is 1：1：8. Fruit yield is 3 263 kg/667 m^2 with 85% first grade fruit. Light interception in the canopy is 58% while the ratio of canopy with good light is 65%. Modified slender spindle （MSS） orchard has 93 thousands shoots per 667 m^2 and the coverage is 77%. Leaf area index is 3.3. The ratio cf long, medium and spur shoots is 1：2：7. Fruit yield is 3 931 kg/667 m^2 with 85% first grade fruit. The light interception in the canopy is 73% while the ratio of canopy with good light is 35%. [Conclusion] Apple orchard with M26 dwarf rootstock trained as SS and MSS tree form in medium planting density may be useful to the management of the similar orchards in Central China.展开更多
A new endophytic antagonistic fungus, Chaetomium spirale ND35 from Populus tomentosa, was reported. The bio-control trials of C. spirale ND35 against the Valsa Canker of apple were preliminarily investigated. The resu...A new endophytic antagonistic fungus, Chaetomium spirale ND35 from Populus tomentosa, was reported. The bio-control trials of C. spirale ND35 against the Valsa Canker of apple were preliminarily investigated. The results of dual culture on PDA plate showed that C. spirale ND35 was capable of strong antagonism against Valsa ceratosperma, and for inhibiting the mycelial growth of V. ceratosperma,.the crude extract of liquid culture of corn steep powder broth was more effective than that one of malt extract broth (MEB). The results of bio-control in greenhouse and field indicated that the disease incidence of apple tree treated with C. spirale ND35 was lower significantly than that treated by other methods. The re-isolation experiment suggested that C. spirale ND35 could colonize in stems and branches of apple trees successfully, and the ND35 colonization rate of the treatment with solid wheat bran culture was higher than that of corn steep powder broth, but the field experiment result the control effect of liquid culture of C. spirale ND35 was better than that of solid culture.展开更多
基金support by the National Key Technologies R&D Program of China during the 11th Five-Year period(2006BAD09B09)Foundation of Shaanxi Province Education Committee,China (09JS073)+1 种基金the Specialdized Research Fund for the Doctoral Program of Higher Education,China (SRFDP200807181008)the Key Program of Baoji University of Arts and Sciences,China (ZK0846)
文摘The vertical distribution pattern and seasonal dynamics of fine root parameters for the apple trees of different ages （3, 10, 15, and 20 years old） on the Loess Plateau of China were studied. Soil coring method was used to determine the vertical distribution and seasonal dynamics of fine roots at different root radial distances （1.0, 1.5, and 2.0 m from the main tree trunk）. The fine root biomass density （FRD）, fine root length density （RLD）, and specific root length （SRL）, as well as soil water content and soil temperature were also measured. The FRD and RLD for the 10, 15, and 20 years old trees reached peak values in the 20-30 cm soil layer. For the 3 years old tree, the highest FRD and RLD were observed in the 10-20 cm soil layer. The FRD and RLD decreased with increased soil depth from the 10-20 or 20-30 cm soil layer for all age apple trees. The SRL declined with the increase of tree age. The FRD at the 1.0 m radial distance from the main tree trunk was higher than that at other radial distances in the 3 and 10 years old orchard. However, in the 15 and 20 years old orchards, especially the 20 years old orchard, the FRD at the 2.0 m radial distance was nearly equal to or higher than that at the 1.0 and 1.5 m radial distances. For all the root radiuses or the tree ages, the FRD, RLD, and SRL were the highest in spring and the lowest in autumn. The age of an apple tree does not affect the vertical distribution pattern but the biomass of fine roots and the SRL. Radial distance affects the root horizontal distribution of 3 and 10 years old trees but the 15 and 20 years old trees. Additionally, effects of soil temperature and soil moisture on fine root distribution or seasonal dynamics are not significant.
基金Supporting founds:National Key R&D Program(2016YFC0400204)Natural Science Foundation of China(51479161,51279157,51779205)。
文摘Six-year old apple trees were selected for field experiment.The objective of this study was to obtain the reasonable arrangement of surge-root irrigation emitters in apple orchards.There were three factors:the buried depth H(25,40,55 cm),the horizontal distance L(30,40,60 cm)between the emitters and the trunk of the experimental tree,and the number of the irrigation emitters N(1,2,4).The effect of the arrangement of surge-root irrigation emitters on the growth,yield and irrigation water use efficiency(IWUE)of apple trees were studied in Northern Shaanxi where the irrigation quota takes 60%-75%of the field water capacity.The results showed that the arrangement of emitters for surge-root irrigation had a significant effect on apple tree yield and IWUE,especially,the yield and IWUE reached 28388.17 kg/hm2 and 16.83 kg/m3 in treatment T3,respectively.At the same L and N levels(T1,T2,and T3),the yield and IWUE in treatment T3 were the highest,and the yields in treatments T1 and T2 were decreased by 26.22%and 31.48%,while IWUE is reduced by14.02%and 18.12%compared with T3,respectively.At the same H and N levels(T3,T4,and T5),the yield and IWUE of apple trees were decreased with increasing L level.Especially,when L was 30 cm(T3),the yield and IWUE were the highest.The same L and H levels(T3,T6,and T7)could promote the growth of apple trees when N was 2(T3).Compared with treatment T3,it was found that the increment of new shoots was decreased by 8.07%-18.71%,and the fruit diameter was decreased by 5.41%-9.11%.Therefore,two emitters should be arranged symmetrically on both sides of an apple tree,each was buried at a 40 cm depth and 30 cm away from the trunk of the tree to effectively improve the yield and IWUE of the apple tree in mountainous areas in Northern Shaanxi.
文摘Red Fuji apple trees of Zn-deficiency were used as material in the experiment. The effect of different Zn application methods on the regularity of Zn transportation and nutrition was studied. It was found that the storage of Zn in the branches was greatly increased by foliar application of the solution of 15% ZnSO4·7H2O before abscission. It had advantage to keep suitable Zn content in leaves, branches and roots, as well as between Zn and P and K, which increased Zn transportation and reusability. Zn content in roots increased when Zn was used in soil in autumn. However, the absorbed Zn did not transport to the top of the plant. It was used by the plant next year. Foliar application of ZnSO4·7H2O at early stage of the plant growth enhanced Zn content of the branch. However, the effect was kept for a short time. It had little effect on Zn transportation when Zn was sprayed three weeks after blossoming.
文摘The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) during soil drought stress. ABA concentration in drought stressed leafless trees increased significantly compared to the controls. ABA both in roots and xylem rose steadily in the earlier drought stage, reaching a maximum of 1.46±0.35 nmol g\+\{ 1\}FW and 117 nmol l\+\{-1\} after the 8th day. Similar change patterns of ABA concentration was observed in the leafy trees during soil drought stress; ABA concentrations in roots and xylem sap increased and reached the maximum in the first three days; after 8th day , it decreased slightly, whereas leaf ABA concentration increased steadily in drought stressed plants throughout the duration of the experiment. Between drought stressed and control trees, no significant differences were observed in concentration of ZR and DHZR in both leafless and leafy trees; whereas iPA concentration of the drought stressed leafless and leafy plants decreased markedly in the later stage of drought. These results showed that endogenous ABA originated mainly from the roots in the earlier drought stage, and mainly from the leaves in the later drought stage. Total CTK showed no reduction in the earlier drought stage and decreased in the later drought stage.
文摘Method: Use Multiple Scattering Correction to eliminate the interference of scattering on spectrum in the process of field measurement so as to improve the accuracy of prediction model of tree canopy nitrogen content. Apple trees in Qixia of Yantai City were taken as the test material. The spectral reflectivity of apple tree canopy went through the First Derivative (FD) and Multiple Scattering Correction (MSC) plus first derivative, respectively. The correlation coefficients were calculated between spectral reflectivity and nitrogen content. The Support Vector Machine (SVM) method was used to establish the prediction model. The result indicates that the MSC pre-processing can improve the correlation between spectral reflectivity and nitrogen content. The SVM model with MSC + FD pre-processing was a good way to predict the nitrogen content. The calibration R<sup>2</sup> of the model was 0.746;the validation R2 was 0.720;and its RMSE was 0.452 g·kgˉ<sup>1</sup>. MSC can commendably eliminate scattering error to improve the prediction accuracy of prediction model.
基金This paper was supported by the National Natural Science Foundation of China(41671346)the National Key Research and Development Program of China(2017YFE0122500)+1 种基金Shandong Major Scientific and Technological Innovation Project(2018CXGC0209)the Taishan Scholar Assistance Program from Shandong Provincial Government,Funds of Shandong“Double Tops”Program(SYL2017XTTD02).
文摘The nutrient inversion model of apple leaves was established by spectral analysis technology to provide technical support for the fine management of apple trees.In Shuangquan Town,Changqing District,Jinan City,Shandong Province,the Fuji apple trees with stopping period of spring shoots were taken as research objects.The spectral reflectance and nitrogen content of apple leaves were measured by ASD Field Spec 4 portable ground object spectrometer.Analyzed the correlation between leaf nitrogen content and spectral reflectance.The sensitive wavelengths with high correlation coefficient were select by fractional differential algorithm,and the optimal vegetation index was constructed and screened out.Partial Least Square Regression(PLSR),Support Vector Machine(SVM)and Random Forests(RF)method were used to construct an inversion model of leaf nitrogen content.The results show that the RF model based on fractional differential second-order treatment is the best inversion model for the nitrogen content of leaves during stopping period of spring shoots.The modeling accuracy determination coefficient R2 reached 0.891,RMSE was 0.0841,and RPD was 2.1396.The determination coefficient R2 of the fitting results of the verification set was 0.617,RMSE was 0.1251,and RPD was 1.7105.The inversion model established by RF method is effective in monitoring the nitrogen content in apple leaves,which provides a theoretical basis for monitoring the growth of apple by hyperspectral technology.
文摘A long time ago,there was a huge apple tree.Alittle boy loved to come and lay around it everyday.He climbed to the tree top,ate the apples,took a napunder the shadow…He loved the tree and the treeloved to play with him. Time went by…The little boy had grown
文摘At present, with the continuous improvement of China's agricultural construction level, it has objectively driven China's economic development. As a country with a large population, China's agricultural economy has been an important part of China's economic construction for a long time, and has a vital practical significance. Among them, apple itself is favored by many agricultural growers because of its advantages of good taste, high nutrition and high acceptance by people. However, in the process of apple tree planting, it will be affected by many problems, which requires further management of apple tree planting and pest control to ensure the quality of apple tree planting. Therefore, in order to further improve the cultivation quality of apple trees and do a good job in the cultivation management and pest control of apple trees, this paper mainly aims at the optimization measures of apple tree cultivation management and the pest control technology of apple trees, and puts forward specific feasible methods from various angles, which can provide effective reference for the subsequent work.
文摘Apple is an important cash crop. Because of its rich nutrition, sweet taste and rich iron, it is an important fruit to improve human immunity. Because the demand for apples in the market is relatively large, high yield and quality should be considered by growers. When fruit trees are cultivated, the technique of dwarfing and close planting can advance the fruit bearing time of fruit trees and help people to obtain economic benefits. At the same time, it can also make efficient use of the orchard. Therefore, in the cultivation stage, people can use this technology to dwarf the apple trees, effectively control the crown area, increase the single volume and increase the economic benefits. Based on the in-depth analysis of the technical points such as dwarfing dense planting and management, and according to the market demand, the present situation of dwarfing cultivation of fruit trees is analyzed, and the technical points such as scientific land selection, dwarfing rootstocks, density control, crown pruning, water and fertilizer management, orchard clearing and pest prevention are put forward, so as to explore the efficient management technology of apple tree dwarfing culture.
基金financially supported by the National Natural Science Foundation of China(Grant No.52309050)the Key R&D and Promotion Projects in Henan Province(Science and Technology Development)(Grant No.232102110264)+1 种基金Youth Backbone Teacher Project of Henan University of Science and Technology(Grants No.13450013 and 13450010)the Key Scientific Research Projects of Colleges and Universities in Henan Province(Grant No.24B416001).
文摘As a crucial fruit tree crop,the health and yield of apple trees are intricately linked to soil moisture conditions.This study aimed to integrate the enhanced WOFOST model with the HYDRUS model to simulate the growth and development of apple trees,as well as the dynamics of soil moisture under varying degrees of water deficit.The outputs of evapotranspiration(ET0)and leaf area index(LAI)from the WOFOST model during the apple growth phase were specifically integrated with HYDRUS-1D.These parameters served as intermediaries to assess the impact of different water deficit scenarios on apple tree growth and soil moisture content.The experimental design included three levels of water deficit treatments in addition to control,with irrigation volumes for the deficit treatments set at 85%,70%,and 55%of the control’s volume,respectively.The model-predicted LAI across all irrigation treatments exhibited an R^(2) range of 0.89-0.95,a normalized root mean square error(NRMSE)between 8.02%and 14.57%,and yield prediction errors ranging from 6.27%to 9.61%,closely aligned with empirical data.The accuracy of simulated soil moisture content was enhanced in the 0-30 cm layer,with a slight decrease in accuracy observed in the 30-60 cm layer.For each irrigation treatment,the R^(2) values for simulated soil moisture content ranged from 0.77 to 0.89 in the 0-30 cm layer and from 0.75 to 0.81 in the 30-60 cm layer.This study validated the capability of the WOFOST-HYDRUS model to accurately simulate the effects of varied water deficit treatments on soil moisture,LAI,and apple tree yield,providing valuable insights for developing optimal irrigation strategies.
基金funded by the Natural Science Foundation of China(42171303,42371373)the Special Fund for Construction of Scientific and Technological Innovation Ability of Beijing Academy of Agriculture and Forestry Sciences(KJCX20230434).
文摘Accurate monitoring and spatial distribution of the leaf chlorophyll content(LCC)and canopy chlorophyll content(CCC)of individual apple trees are highly important for the effective management of individual plants and the promotion of the construction of modern smart orchards.However,the estimation of LCC and CCC is affected by shadows caused by canopy structure and observation geometry.In this study,we resolved the response rela-tionship between individual apple tree crown spectra and shadows through a three-dimensional radiative transfer model(3D RTM)and unmanned aerial vehicle(UAV)multispectral images,assessed the resistance of a series of vegetation indices(VIs)to shadows and developed a hybrid inversion model that is resistant to shadow inter-ference.The results revealed that(1)the proportion of individual tree canopy shadows exhibited a parabolic trend with time,with a minimum occurring at noon.Correspondingly,the reflectance in the visible band decreased with increasing canopy shadow ratio and reached a maximum value at noon,whereas the pattern of change in the reflectance in the near-infrared band was opposite that in the visible band.(2)The accuracy of chlorophyll content estimation varies among different VIs at different canopy shadow ratios.The top five VIs that are most resistant to changes in canopy shadow ratios are the NDVI-RE,Cire,Cigreen,TVI,and GNDVI.(3)For the con-structed 3D RTM+GPR hybrid inversion model,only four VIs,namely,NDVI-RE,Cire,Cigreen,and TVI,need to be input to achieve the best inversion accuracy.(4)Both the LCC and the CCC of individual trees had good validation accuracy(LCC:R^(2)=0.775,RMSE=6.86μg/cm^(2),nRMSE=12.24%;CCC:R^(2)=0.784,RMSE=32.33μg/cm^(2),and nRMSE=14.49%),and their distributions at orchard scales were characterized by considerable spatial heterogeneity.This study provides ideas for investigating the response between individual tree canopy shadows and spectra and offers a new strategy for minimizing the influence of shadow effects on the accurate estimation of chlorophyll content in individual apple trees.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2017YFD0201508).
文摘Nitrogen(N)is an important mineral element in apple production.Rapid estimation of apple tree N status is helpful for achieving precise N management.The objective of this work was to explore partial least squares(PLS)regression in dimensional reduction of spectral data and build the diagnostic model.The spectral reflectance data were collected from Fuji apple trees with 4 levels of N fertilizer treatment in the Loess Plateau in 2018 and 2019 using an ASD portable spectroradiometer,and leaf total N content was obtained at the same time.The raw spectra were pretreated using Savitzky-Golay(SG)smoothing and a combination of SG and first-order derivative(SG_FD)or second-order derivative(SG_SD).The samples were divided into a calibration dataset and a prediction dataset using SPXY.Based on 4 factors of PLS regression,including latent variables(LVs),X-loading,variable importance in projection(VIP)and regression coefficients(RC),the 6 methods(LVs,X-loading,VIP_01,VIP_02,RC_01 and RC_02)were derived and used for variable extraction,based on which PLS model and ELM model were established.The results indicated that the spectral data processed by SG_FD had the highest signal-to-noise ratio and was selected for subsequent analysis.The amounts of variables extracted by LVs,X-loading,VIP_01,VIP_02,RC_01 and RC_02 were 6,11,18,305,26 and 88,respectively.The method of extracting variables with an RC threshold based on the minimum RMSEP(RC_02)could effectively avoid the omission of effective information.The RC_02 method was recommended for related research which required accurate wavelength information as a variable.The variable extraction method based on LVs generated an ELM model with a simple structure.The prediction results showed that the ELM model outperformed the PLS model.The PLS(LVs)_ELM model was the best;R2P,RMSEP and RPD were 0.837,2.393 and 2.220,respectively.
基金supported by the Chinese National Natural Science Foundation(grant numbers 51109154,51579168,U1803112)the Shanxi Province National Natural Science Foundation(grant number 201601D011053).
文摘Water storage pit irrigation is a new method suitable for apple trees.It comes with advantages such as water saving,water retention and drought resistance.A precise study of soil water movement and root water uptake is essential to analyse and show the advantages of the method.In this study,a mathematical model(WSPI-WR model)for 3D soil water movement and root water uptake under water storage pit irrigation was established based on soil water dynamics and soil moisture and root distributions.Moreover,this model also considers the soil evaporation,pit wall evaporation and water level variation in the pit.The finite element method was used to solve the model,and the law of mass conservation was used to analyse the water level variation.The model was validated by experimental data of the sap flow of apple trees and soil moisture in the orchard.Results showed that the WSPI-WR model is highly accurate in simulating the root water uptake and soil water distributions.The WSPI-WR model can be used to simulate root water uptake and soil water movement under water storage pit irrigation.The simulation showed that orchard soil water content and root water uptake rate centers on the storage pit with an ellipsoid distribution.The maximum distribution region of soil water and root water uptake rate was near the bottom of the pit.Distribution can reduce soil evaporation in the orchard and improve the soil water use efficiency in the middle-deep soil.
基金supported by the National Natural Science Fundation of China (51621061, 91425302) the 111 Program of Introducing Talents of Discipline to Universities (B14002)
文摘Alternate partial root-zone irrigation(APRI)can improve water use efficiency in arid areas. However,the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use have not been reported. A two-year field experiment was conducted with two irrigation amounts(400 and500 mm) and three irrigation methods(conventional irrigation, APRI with high and low frequencies). Root length density, stomatal conductance, photosynthetic rate,transpiration rate, leaf water use efficiency, midday stem and leaf water potentials were measured. The results show that in comparison with conventional irrigation, APRI with high frequency significantly increased root length density and decreased water potentials and stomatal conductance.No differences in the above indicators between the two APRI frequencies were detected. A significantly positive relationship between stomatal conductance and root length density was found under APRI. Overall, alternate partial root-zone irrigation with high frequency has a great potential to promote root growth, expand water uptake capacity and reduce unproductive water loss in the arid apple production area.
基金Supported by National Apple Industry Programs of Ministry of Agriculture(CARS-28)~~
文摘[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close planting of dwarf rootstock apples.[Method] The technical parameters of individual trees and group parameters as shoot number and composition and canopy coverage were determined, and the light quality in the canopy, fruit production and quality were investigated. [Result] Slender spindle （SS） orchard has 54 thousands shoots per 667 m^2. Coverage rate is 76%. Leaf area index is 1.9. The ratio of long, medium and spur shoots is 1：1：8. Fruit yield is 3 263 kg/667 m^2 with 85% first grade fruit. Light interception in the canopy is 58% while the ratio of canopy with good light is 65%. Modified slender spindle （MSS） orchard has 93 thousands shoots per 667 m^2 and the coverage is 77%. Leaf area index is 3.3. The ratio cf long, medium and spur shoots is 1：2：7. Fruit yield is 3 931 kg/667 m^2 with 85% first grade fruit. The light interception in the canopy is 73% while the ratio of canopy with good light is 35%. [Conclusion] Apple orchard with M26 dwarf rootstock trained as SS and MSS tree form in medium planting density may be useful to the management of the similar orchards in Central China.
基金This research was supported by National Natural Science Foundation of China (Grant No. 30100143)
文摘A new endophytic antagonistic fungus, Chaetomium spirale ND35 from Populus tomentosa, was reported. The bio-control trials of C. spirale ND35 against the Valsa Canker of apple were preliminarily investigated. The results of dual culture on PDA plate showed that C. spirale ND35 was capable of strong antagonism against Valsa ceratosperma, and for inhibiting the mycelial growth of V. ceratosperma,.the crude extract of liquid culture of corn steep powder broth was more effective than that one of malt extract broth (MEB). The results of bio-control in greenhouse and field indicated that the disease incidence of apple tree treated with C. spirale ND35 was lower significantly than that treated by other methods. The re-isolation experiment suggested that C. spirale ND35 could colonize in stems and branches of apple trees successfully, and the ND35 colonization rate of the treatment with solid wheat bran culture was higher than that of corn steep powder broth, but the field experiment result the control effect of liquid culture of C. spirale ND35 was better than that of solid culture.
