[ Objective] The aim of this study was to investigate the dynamic distribution of endophytic rhizobia in different plant parts during seed development of alfalfa and the carrying mechanism of endophytic rhizobia from ...[ Objective] The aim of this study was to investigate the dynamic distribution of endophytic rhizobia in different plant parts during seed development of alfalfa and the carrying mechanism of endophytic rhizobia from alfalfa seeds. [ Method] Root, stem, leaf, flower, pod and seed from two varieties of alfalfa in different development stages were used for surface disinfection, and then the present site and quantity change of rhizobia in alfalfa were studied by the dilution - plate method. [ Result] The number of rhizobia from underground plants in the same stage was as follows： main root 〈 lateral root 〈 hair root. The number of rhizobia from main root and hair root in different stages was as follows： bearing pod stage 〉 branching stage 〉 florescence, while that from lateral root was as follows： branching stage 〉 florescence 〉 bearing pod stage. The distribution of endophytic rhizobia from aerial plants was as follows： few rhizobia was found in stem during branching stage and bearing pod stage, which accounted for 155 cfu/g and 125 cfu/g respectively. Rhizobia mainly distributed in flower bud during branching stage accounting for 9 400 cfu/g, while only in ovary wall during squaring stage accounting for 18 cfu/5 flowers, and few in pollen （26 cfu/5 flowers）, fertilized ovules （26 cfu/50 grains）, receptacle （15 cfu/5 flowers） and ovary wall （95 cfu/5 flowers） during florescence. Rhizobia existed in pod peel （3 550 cfu/5 pods） and immature seed （1 135 cfu/50 grains） during bearing pod stage, and greatly distributed in seed coat of mature seeds （1 435 cfu/50 grains）, but only few in embryo （32 cfu/50 grains） and cotyledon （22 cfu/50 grains）. [ Cenclusion] There is a significant difference in the distribution of endophytic rhizobia from different parts of aerial alfalfa, which only exists in the parts directly related to seed development.展开更多
[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used...[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used to determine the con- tent of imidacloprid in different parts of tobacco plants （roots, stems, the upper, middle and lower leaves） at different time. [Results] The imidacloprid could be absorbed by root and could be transported to all parts of the tobacco plant after irrigating root, but the original deposition amount was larger and the transport efficiency was lower after spraying. [Conclusion] The translocation and distribution of imidacloprid by spraying was more uniform and the holding efficiency was better, but imidacloprid with root irrigation could act on leaf directly, and had better readily availability.展开更多
[Objective] In order to study plant adaptation mechanism under different landforms in drought regions.[Method] Observe soil moisture dynamic of Salix psammophila sample areas on the dune and depression with neutron mo...[Objective] In order to study plant adaptation mechanism under different landforms in drought regions.[Method] Observe soil moisture dynamic of Salix psammophila sample areas on the dune and depression with neutron moisture gauge and research the roots distribution of Salix psammophila sample areas on the dune and depression respectively by digging method.[Result] The quantity of Salix psammophila roots on the dune exponentially decreases while that on the depression decreases by power function in horizontal direction.In vertical direction,Salix psammophila roots on the dune are mainly distributed in 0-30 and 80-120 cm layers as 72% of all,while Salix psammophila roots on the depression are mainly distributed in 0-40 cm layers as 54% of all.[Conclusion] Salix psammophila roots on the dune not only use surface soil water but also use middle-layer groundwater.Salix psammophila roots on the depression primarily use surface soil water.展开更多
The gas_well system permanently installed in the soil was adopted for studying the dynamic relationship between CO 2 profiles and seedling root growth of Pinus sylvestris var. sylvestriformis (Takenouchi) Che...The gas_well system permanently installed in the soil was adopted for studying the dynamic relationship between CO 2 profiles and seedling root growth of Pinus sylvestris var. sylvestriformis (Takenouchi) Cheng et C. D. Chu. The study was conducted in the Open Research Station of Changbai Mountain Forest Ecological System, The Chinese Academy of Sciences from 1999 to 2001. Four treatments were arranged in the rectangular open_top chambers (OTCs): ambient CO 2+no_seedling, 700 μmol/mol CO 2+no_seedling, ambient CO 2 +seedlings, 700 μmol/mol CO 2+seedlings. By collecting and analyzing soil gas synchronously, it was found that the dynamics of CO 2 profiles were related to the biological activity of seedlings. There were more roots distributed in the top soil and the boundary layer across soil and sand, which made more contributions to the CO 2 profiles due to respiration root. Compared with the ambient CO 2, elevated CO 2 led to the peak of CO 2 concentration distribution shifted from soil surface layer to the boundary layer as seasonally growing of seedling roots. It is suggested the gas_well system is an inexpensive, non_destructive and relatively sensitive method for study of soil CO 2 concentration profiles.展开更多
The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in ...The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in early spring, 2001. It is found that ash and larch differ greatly in their belowground biomass distribution. Ash has much higher fine root biomass density in the soil than larch at stand level (with the max value of 4442.3 vs. 2234.9 gm-3). Both tree species deployed more fine roots in their neighboring zone, suggesting a less intensive competition between roots of the two species. Both fine root biomass density and root length density of ash in the zone between larch tree rows are greater than that of larch in zone between ash tree rows, indicating that ash is more powerful than larch in belowground competition. The spatial distribution feature of roots favors the growth of ash in the mixed stand.展开更多
The depletion rate of phosphate in the soil-root interface zone increased along with growth and phosphateuptake of wheat or maize, which indicated that the phosphate distribution in soil near the root surfaceagreed we...The depletion rate of phosphate in the soil-root interface zone increased along with growth and phosphateuptake of wheat or maize, which indicated that the phosphate distribution in soil near the root surfaceagreed well with the phosphate movement in rhizosphere and phosphate uptake by plant. The relativeaccumulation zone of phosphate within 0.5 mm apart from the root surface developed at the 15th day or soafter cultivating wheat or maize since the root phosphate secretion increased gradually in this stage. Thephosphate distribution in the soil-root interface zone against the growing time (t) and the distance from theroot plane (x) could be described by the non-linear regression equation with the third powers of x and t.展开更多
Biodiversity of arbuscular mycorrhizal colonization and spore population was investigated in different agroforestry trees and crop species collected from different locations of Dinajpur district of Bangladesh. Roots a...Biodiversity of arbuscular mycorrhizal colonization and spore population was investigated in different agroforestry trees and crop species collected from different locations of Dinajpur district of Bangladesh. Roots and rhizosphere soils of Albizia procera Benth., Capsicum frutescens L, Curcuma domestica Vahl., Dalbergia sissoo Roxb. and Swietenia macrophylla King. from Dashmail; C. domestica, D. sissoo, Eucalyptus camaldulensis Dehnn., Gmelina arborea （Roxb） DC and Oryza sativa L. from Kantaji and C. domestica, D. sissoo, Litchi chinensis Sonn. and O. sativa from Ramsagar were collected. Roots and soils were assessed following standard methods. The range of AM colonization was recorded 36%-79% from Dashmail. The highest AM colonization was recorded in C. frutescens （79%） and the lowest was in C. domestica （36%）. The range of colonization was recorded as 33%-70% from Kantaji. The highest AM colonization was recorded in G. arborea （70%） and the lowest was in O. sativa （33%）. The range of AM colonization was recorded as 35%-70% from Ramsagar. The highest AM colonization was recorded in D. sissoo （70%） and the lowest was in O. sativa （35%）. Arbuscular mycorrhizal spore population varied from 54 to 140/100g dry soil in the soils from Dashmail. The highest was in the soils of D. sissoo （140） and the lowest was in C. domestica （54）. The spore population varied from 63 to 221 in Kantaji. The highest was in G. arborea （221） and the lowest was in O. sativa （63）. The range population in Ramsagar varied from 69 to 160. The highest was recorded in D. sissoo （160） and the lowest was in L. chinensis （69）. No significant relationship of soil pH and soil OM with AM colonization and with spore population was observed. Simpson＇s index of diversity （Ds） and Shannon＇s index of diversity- （Hs） were highest in the soil of D. sissoo from Kantaji and the lowest in the soils of O. sativa from Ramsagar. Biodiversity of AM colonization, spore population and the distribution of AM fungi in the rhizosphere soils of different agroforestry plants indicated the occurrence of AM fungi, mycotrophic nature of the trees and crop species, contribution and necessity of AM fungi and the AM dependence of the agroforestry plants growing in Dinajpur district of Bangladesh.展开更多
The root morphology of erect type peanut in deep soil was studied in this paper. In the experiment, erect type peanut showed as most as five-order lateral roots with 13 227 pieces of lateral roots. At the seedling sta...The root morphology of erect type peanut in deep soil was studied in this paper. In the experiment, erect type peanut showed as most as five-order lateral roots with 13 227 pieces of lateral roots. At the seedling stage, the root system of erect type peanut was handstand cone-typed with lateral roots at various orders distributed around the taproot, and among the roots, the taproot was longest. During the late seedling stage to mature stage, the upper part of the root system of erect type peanut was blunt cone-typed, the middle part was three-dimensional network typed, while the lower part was cyUnder-like. The longest first-order lateral root was the longest root. At the mature stage, the taproot was not always the deepest root.展开更多
The aim of this study was to determine the nematicidal effects of some biopesticides againist root-knot nematodes （RKNs） （Meloidogyne incognita） on Bruno type kiwifruit seedlings. Research was conducted in the Ata...The aim of this study was to determine the nematicidal effects of some biopesticides againist root-knot nematodes （RKNs） （Meloidogyne incognita） on Bruno type kiwifruit seedlings. Research was conducted in the Atattirk Central Horticultural Research Institute （ACHRI, Yalova, Turkey） greenhouse during 2013-2014. Biopesticides observed in this study were： sesame oil （Devalone EC）, castor oil （Ricinus communis）, Myrothecium verrucaria （M. verrucaria strain AARC-0255, Inferno DF）, Glomus spp. （Endomycorrhizal fungi, Endo Roots Soluble SP） and Paecilomyces lilacinus （Entomopathogenic fungi, P. lilacinus strain PL1, Bionematon SL）. Nematicide Nemacur EC 400 （fenamiphos） was used as treated control （TC） and trials were set up as randomized parcel design （RPD） with seven characters and 10 replicates. Reproduction ratio was determined according to scale values in trial applications and second stage juvenile （J2） populations of M. incognita in soil. The results showed that the best nematicidal effects against RKNs were determined in castor oil （77.92% in 2013 and 73.61% in 2014） and P. lilacinus （61.03% in 2013 and 55.55% in 2014）.展开更多
While the occurrence of rainfall is a regional scale phenomenon, cities influence on precipitation spatial distribution patterns and their characteristics. These influences had been studied for a very long time especi...While the occurrence of rainfall is a regional scale phenomenon, cities influence on precipitation spatial distribution patterns and their characteristics. These influences had been studied for a very long time especially in the Northern Hemisphere. Tandil and Bahia Blanca are middle cities of Argentina located in the south of Buenos Aires province. Both present continental template climate. The aim of this research is to analyze the spatial distribution patterns of precipitation and the rainwater pH values for the period October 2010-September 2011 in Tandil and Bahia Blanca. Gauge rain nets were installed in both cities. In each event of precipitation, amount and pH values were collected. Isohyets plotting were included in the thematic cartography that was made using ArcGis 9.3~ software. Although natural rains are generally considered as being weakly acid, the rainwater pH measurements demonstrated that in both cities the rain is alkaline. Regarding to the spatial distribution of the precipitation amounts, the isohyets of the annual records showed that the highest values were registered in areas of higher elevation while the lowest values were presented in both cities downtown, where the high buildings are concentrated.展开更多
基金Supported by Project of Ministry of Science and Technology"Researchand Demonstration on Northwest Advantages and Key Pro Ductive-Pro-cessing Technique for Featured Forage"(2007BAD52B06)Research andDevelopment of Production Technology of High Quality Forage for Cows(2006BAD04A04)+1 种基金New Variety Breeding of Special Forage with GoodQuality and Stress Resistance(2006BAD01A19)Special Fund of Ministryof Agriculture"Research and Demonstration on Production Technology of High Quality Forage in Artificial Grass lands"(nyhyzx07-022)~~
文摘[ Objective] The aim of this study was to investigate the dynamic distribution of endophytic rhizobia in different plant parts during seed development of alfalfa and the carrying mechanism of endophytic rhizobia from alfalfa seeds. [ Method] Root, stem, leaf, flower, pod and seed from two varieties of alfalfa in different development stages were used for surface disinfection, and then the present site and quantity change of rhizobia in alfalfa were studied by the dilution - plate method. [ Result] The number of rhizobia from underground plants in the same stage was as follows： main root 〈 lateral root 〈 hair root. The number of rhizobia from main root and hair root in different stages was as follows： bearing pod stage 〉 branching stage 〉 florescence, while that from lateral root was as follows： branching stage 〉 florescence 〉 bearing pod stage. The distribution of endophytic rhizobia from aerial plants was as follows： few rhizobia was found in stem during branching stage and bearing pod stage, which accounted for 155 cfu/g and 125 cfu/g respectively. Rhizobia mainly distributed in flower bud during branching stage accounting for 9 400 cfu/g, while only in ovary wall during squaring stage accounting for 18 cfu/5 flowers, and few in pollen （26 cfu/5 flowers）, fertilized ovules （26 cfu/50 grains）, receptacle （15 cfu/5 flowers） and ovary wall （95 cfu/5 flowers） during florescence. Rhizobia existed in pod peel （3 550 cfu/5 pods） and immature seed （1 135 cfu/50 grains） during bearing pod stage, and greatly distributed in seed coat of mature seeds （1 435 cfu/50 grains）, but only few in embryo （32 cfu/50 grains） and cotyledon （22 cfu/50 grains）. [ Cenclusion] There is a significant difference in the distribution of endophytic rhizobia from different parts of aerial alfalfa, which only exists in the parts directly related to seed development.
基金Supported by the Key Science and Technology Project of Jinlin Tobacco Industrial Co.,Ltd.(JS-2015-07)the Scientific and Technological Innovation Project of Chinese Academy of Agricultural Sciences(ASTIP-TRIC06)~~
文摘[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used to determine the con- tent of imidacloprid in different parts of tobacco plants （roots, stems, the upper, middle and lower leaves） at different time. [Results] The imidacloprid could be absorbed by root and could be transported to all parts of the tobacco plant after irrigating root, but the original deposition amount was larger and the transport efficiency was lower after spraying. [Conclusion] The translocation and distribution of imidacloprid by spraying was more uniform and the holding efficiency was better, but imidacloprid with root irrigation could act on leaf directly, and had better readily availability.
基金Supported by Science and Technology Research Major Project ofthe Ministry of Education (308021)Publicly-Traded Research Pro-ject of the Ministry of Land and Resources (200911004)~~
文摘[Objective] In order to study plant adaptation mechanism under different landforms in drought regions.[Method] Observe soil moisture dynamic of Salix psammophila sample areas on the dune and depression with neutron moisture gauge and research the roots distribution of Salix psammophila sample areas on the dune and depression respectively by digging method.[Result] The quantity of Salix psammophila roots on the dune exponentially decreases while that on the depression decreases by power function in horizontal direction.In vertical direction,Salix psammophila roots on the dune are mainly distributed in 0-30 and 80-120 cm layers as 72% of all,while Salix psammophila roots on the depression are mainly distributed in 0-40 cm layers as 54% of all.[Conclusion] Salix psammophila roots on the dune not only use surface soil water but also use middle-layer groundwater.Salix psammophila roots on the depression primarily use surface soil water.
文摘The gas_well system permanently installed in the soil was adopted for studying the dynamic relationship between CO 2 profiles and seedling root growth of Pinus sylvestris var. sylvestriformis (Takenouchi) Cheng et C. D. Chu. The study was conducted in the Open Research Station of Changbai Mountain Forest Ecological System, The Chinese Academy of Sciences from 1999 to 2001. Four treatments were arranged in the rectangular open_top chambers (OTCs): ambient CO 2+no_seedling, 700 μmol/mol CO 2+no_seedling, ambient CO 2 +seedlings, 700 μmol/mol CO 2+seedlings. By collecting and analyzing soil gas synchronously, it was found that the dynamics of CO 2 profiles were related to the biological activity of seedlings. There were more roots distributed in the top soil and the boundary layer across soil and sand, which made more contributions to the CO 2 profiles due to respiration root. Compared with the ambient CO 2, elevated CO 2 led to the peak of CO 2 concentration distribution shifted from soil surface layer to the boundary layer as seasonally growing of seedling roots. It is suggested the gas_well system is an inexpensive, non_destructive and relatively sensitive method for study of soil CO 2 concentration profiles.
基金This study was supported by National Natural Science Foundation of China (Grant No. 30130160) and the Quick Response of Basic Research Supporting Program (Grant No.2102)
文摘The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in early spring, 2001. It is found that ash and larch differ greatly in their belowground biomass distribution. Ash has much higher fine root biomass density in the soil than larch at stand level (with the max value of 4442.3 vs. 2234.9 gm-3). Both tree species deployed more fine roots in their neighboring zone, suggesting a less intensive competition between roots of the two species. Both fine root biomass density and root length density of ash in the zone between larch tree rows are greater than that of larch in zone between ash tree rows, indicating that ash is more powerful than larch in belowground competition. The spatial distribution feature of roots favors the growth of ash in the mixed stand.
文摘The depletion rate of phosphate in the soil-root interface zone increased along with growth and phosphateuptake of wheat or maize, which indicated that the phosphate distribution in soil near the root surfaceagreed well with the phosphate movement in rhizosphere and phosphate uptake by plant. The relativeaccumulation zone of phosphate within 0.5 mm apart from the root surface developed at the 15th day or soafter cultivating wheat or maize since the root phosphate secretion increased gradually in this stage. Thephosphate distribution in the soil-root interface zone against the growing time (t) and the distance from theroot plane (x) could be described by the non-linear regression equation with the third powers of x and t.
文摘Biodiversity of arbuscular mycorrhizal colonization and spore population was investigated in different agroforestry trees and crop species collected from different locations of Dinajpur district of Bangladesh. Roots and rhizosphere soils of Albizia procera Benth., Capsicum frutescens L, Curcuma domestica Vahl., Dalbergia sissoo Roxb. and Swietenia macrophylla King. from Dashmail; C. domestica, D. sissoo, Eucalyptus camaldulensis Dehnn., Gmelina arborea （Roxb） DC and Oryza sativa L. from Kantaji and C. domestica, D. sissoo, Litchi chinensis Sonn. and O. sativa from Ramsagar were collected. Roots and soils were assessed following standard methods. The range of AM colonization was recorded 36%-79% from Dashmail. The highest AM colonization was recorded in C. frutescens （79%） and the lowest was in C. domestica （36%）. The range of colonization was recorded as 33%-70% from Kantaji. The highest AM colonization was recorded in G. arborea （70%） and the lowest was in O. sativa （33%）. The range of AM colonization was recorded as 35%-70% from Ramsagar. The highest AM colonization was recorded in D. sissoo （70%） and the lowest was in O. sativa （35%）. Arbuscular mycorrhizal spore population varied from 54 to 140/100g dry soil in the soils from Dashmail. The highest was in the soils of D. sissoo （140） and the lowest was in C. domestica （54）. The spore population varied from 63 to 221 in Kantaji. The highest was in G. arborea （221） and the lowest was in O. sativa （63）. The range population in Ramsagar varied from 69 to 160. The highest was recorded in D. sissoo （160） and the lowest was in L. chinensis （69）. No significant relationship of soil pH and soil OM with AM colonization and with spore population was observed. Simpson＇s index of diversity （Ds） and Shannon＇s index of diversity- （Hs） were highest in the soil of D. sissoo from Kantaji and the lowest in the soils of O. sativa from Ramsagar. Biodiversity of AM colonization, spore population and the distribution of AM fungi in the rhizosphere soils of different agroforestry plants indicated the occurrence of AM fungi, mycotrophic nature of the trees and crop species, contribution and necessity of AM fungi and the AM dependence of the agroforestry plants growing in Dinajpur district of Bangladesh.
文摘The root morphology of erect type peanut in deep soil was studied in this paper. In the experiment, erect type peanut showed as most as five-order lateral roots with 13 227 pieces of lateral roots. At the seedling stage, the root system of erect type peanut was handstand cone-typed with lateral roots at various orders distributed around the taproot, and among the roots, the taproot was longest. During the late seedling stage to mature stage, the upper part of the root system of erect type peanut was blunt cone-typed, the middle part was three-dimensional network typed, while the lower part was cyUnder-like. The longest first-order lateral root was the longest root. At the mature stage, the taproot was not always the deepest root.
文摘The aim of this study was to determine the nematicidal effects of some biopesticides againist root-knot nematodes （RKNs） （Meloidogyne incognita） on Bruno type kiwifruit seedlings. Research was conducted in the Atattirk Central Horticultural Research Institute （ACHRI, Yalova, Turkey） greenhouse during 2013-2014. Biopesticides observed in this study were： sesame oil （Devalone EC）, castor oil （Ricinus communis）, Myrothecium verrucaria （M. verrucaria strain AARC-0255, Inferno DF）, Glomus spp. （Endomycorrhizal fungi, Endo Roots Soluble SP） and Paecilomyces lilacinus （Entomopathogenic fungi, P. lilacinus strain PL1, Bionematon SL）. Nematicide Nemacur EC 400 （fenamiphos） was used as treated control （TC） and trials were set up as randomized parcel design （RPD） with seven characters and 10 replicates. Reproduction ratio was determined according to scale values in trial applications and second stage juvenile （J2） populations of M. incognita in soil. The results showed that the best nematicidal effects against RKNs were determined in castor oil （77.92% in 2013 and 73.61% in 2014） and P. lilacinus （61.03% in 2013 and 55.55% in 2014）.
文摘While the occurrence of rainfall is a regional scale phenomenon, cities influence on precipitation spatial distribution patterns and their characteristics. These influences had been studied for a very long time especially in the Northern Hemisphere. Tandil and Bahia Blanca are middle cities of Argentina located in the south of Buenos Aires province. Both present continental template climate. The aim of this research is to analyze the spatial distribution patterns of precipitation and the rainwater pH values for the period October 2010-September 2011 in Tandil and Bahia Blanca. Gauge rain nets were installed in both cities. In each event of precipitation, amount and pH values were collected. Isohyets plotting were included in the thematic cartography that was made using ArcGis 9.3~ software. Although natural rains are generally considered as being weakly acid, the rainwater pH measurements demonstrated that in both cities the rain is alkaline. Regarding to the spatial distribution of the precipitation amounts, the isohyets of the annual records showed that the highest values were registered in areas of higher elevation while the lowest values were presented in both cities downtown, where the high buildings are concentrated.
