Torreya grandis is a characteristic rare economic tree species in subtropical mountainous areas. The nut has a variety of bioactive compounds, such as polyphenols and vitamins. However, the carotenoids compositions an...Torreya grandis is a characteristic rare economic tree species in subtropical mountainous areas. The nut has a variety of bioactive compounds, such as polyphenols and vitamins. However, the carotenoids compositions and its regulatory mechanisms underlying carotenoid biosynthesis in kernels remain unknown. Here, the major carotenoids in the kernel were analyzed. The result showed that lutein and β-carotene were the predominant carotenoids in the kernel, while low levels of a-carotenoid and zeaxanthin were detected. Lutein and β-carotene were decreased during the maturation of kernel. Expression analysis by RNA-seq and q RT-PCR indicated that the expressions of TgCYP97A3 and TgLCYB were also reduced during the maturation of kernel. The contents of lutein or β-carotene were obviously increased in tobacco transiently overexpressing TgCYP97A3 or TgLCYB. Moreover, DPPH radical scavenging activity and FRAP were also significantly enhanced. In addition, several MYB and WRKY transcription factors TgMYBS3, TgMYB48 and TgWRKY11 were identified to positively regulate the TgCYP97A3 expression, while TgMYB48, TgWRKY2 and TgWRKY11 could upregulate the TgLCYB expression. The illustration of carotenoids biosynthesis and its molecular mechanism in kernels not only provides a basis for understanding carotenoids biosynthesis in kernels, but also enables the use of molecular biotechnology to develop new health products rich in carotenoids based on T. grandis nuts.展开更多
Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation...Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils.Here we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation.The Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope position.The results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere soils.The lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in leaves.Nutrient accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils.Leaf C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope position.The contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively lower.Variations in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere soils.Chemical properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper slope.Correspondingly,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing factor.Overall,these results offer new insights for the sustainability and management of teak plantations in hilly areas.展开更多
Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic...Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely unclear.In this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with age.Seven phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere soils.Most of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years old.The concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in age.Notably,phenolic compounds contributed more to the variation in the understory plants than soil factors.Hydroxyphenyllactic acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation age.These findings indicate that young E.grandis plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential.展开更多
Stains are applied to impart contrast to the tissue and identify particular features of interest. However, the use of synthetic dyes as staining reagents has been associated with significant human health challenges an...Stains are applied to impart contrast to the tissue and identify particular features of interest. However, the use of synthetic dyes as staining reagents has been associated with significant human health challenges and pollution of the ecosystem. These developments have necessitated a shift towards using natural dyes that are eco-friendlier and readily available. We investigated the staining reaction patterns of teak tree leaves (Tectona grandis) dye extracts and explored their suitability as a cytoplasmic stain in micromorphological assessments. Dye extracts were prepared using acetone, methanol, and ethanol as solvents from air-dried (under shade) teak tree young leaves. The dye extracts were applied as a counterstain and evaluated against eosin in formalin-fixed paraffin-embedded (FFPE) bovine tissue sections at varying concentrations and different staining times. Teak tree leaves (Tectona grandis) dye extracts produced relatively varying staining intensities of reddish-brown cytoplasmic coloration when used on bovine tissue at different concentrations and staining times comparable to eosin and with blue-purple hematoxylin nuclear stain. The present study showed that Tectona grandis leaf dye extracts provide an excellent cytoplasmic staining pattern and can be used as an alternative counterstain in routine H&E staining techniques.展开更多
[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis...[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis.展开更多
This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: ...This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: (1) The distribution of ma- jor nutrient element contents in various organs of the E. grandis with the 2 densi- ties was nearly the same, and the ranked order was leaf〉tree trunk〉branch or branchlet〉fruit〉bark. (2) From the distribution of nutrient elements and organic mat- ter in the trunk, P, K, Mg and Ca contents presented basically a trend of increasing with the trunk height increasing. And the organic matter content increased with the trunk height increasing in the low density stand, while the result was opposite in the high density stand. Furthermore, N content increased with the trunk height increas- ing in the low density stand, but the content in the high density stand exhibited a trend of decreasing at first, increasing then and increasing at the last. (3) From the distribution of biomass, the ranked order was tree trunk〉bark or branch〉branchlet〉 leaf〉fruit. And (4) The accumulated amounts of major nutrient elements in various organs under the 2 stand densities was nearly same. Ca content was the highest in the 2 kinds of plantations, followed by N, K, Mg and P contents. Ca content was 601.78 kg/hm2 in the low density stand and 1 204. 43 kg/hm2 in the high density stand.展开更多
The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of n...The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of nutrient elements varied greatly in different organs. Total contents of macroelements N, P, K, Ca and Mg in1a-3a E. grandis were distributed in the order of stem phloem, leaves 〉 branch- es, roots 〉 stem xylem. Accumulated amount of macroelements in 1a-3a E. grandis were in the order of leaves 〉 branches 〉 stem phloem 〉 roots or stem xylem 〉 stem xylem or roots. Accumulated amount law of nutrient elements was not affected by the plant age. Microelements Fe and Zn were mainly concentrated in the leaves and roots. The accumulation of macroelements was in the order of Ca 〉 N 〉 K 〉 Mg 〉 P; and the microelements was in the order of Fe 〉 Zn. Accumulated amounts of microelements in 1a-3a E. grandis were 12.45 136.19 and 420.23 g per plants, respectively. Among the annual net accumulated amount of nutrient ele- ments per plant in 1a-3a E. grandis, Ca element was the maximum, N and K ele- ments took the second and third places. Mg element was relatively small and P el- ement was the minimum.展开更多
[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis...[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis×E.urophylla were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×E.urophylla both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×E.urophylla both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species.展开更多
Objective:To investigate antidiabetic,antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis(T.grandis) flowers(METGF) in streplozotocin(STZ) induced diabetic rats to supports its tradition...Objective:To investigate antidiabetic,antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis(T.grandis) flowers(METGF) in streplozotocin(STZ) induced diabetic rats to supports its traditional use.Methods:Acute toxicity study of METGF was carried out in rat to determine its dose for the antidiabetic study.Oral glucose tolerance test(OGTT) was performed to evaluate METGF effect on elevated blood glucose level.Diabetes was induced in rats by administration of STZ(60 mg/kg,ip.) and it was confirmed 72 h after induction.METGF was orally given to the diabetic rats up to 28 days and blood glucose level were estimated each week.On 28 day of the experiment,diabetic rats were sacrificed after the blood collection for the biochemical parameters analysis and liver,kidney was collected to determine antioxidants levels.Results: In acute toxicity,METGF did not show toxicity and death up to a dose 2 000 mg/kg in rats. Administration of METGF 100 and 200 mg/kg significantly(P【0.001) reduced blood glucose levels in OGTT and STZ-induced diabetic rats.Both doses of METGF treatment significantly(P【0.001, P【0.01 and P【0.05) increased body weight,serum insulin,haemoglobin(Hb) and total protein levels in diabetic rats.Also,MEGTF treatment reduced elevated glycosylated haemoglobin(HbA1c) and other biochemical parameters levels significantly(P【0.001) in diabetic rats.Altered lipid profiles and antioxidants levels were reversed to near normal in diabetic rats treated with METGF. Conclusions:These results concluded that METGF possesses antidiabetic,antihyperglycemic and antioxidant activity which supports its traditional use.展开更多
基金funded by the National Natural Science Foundation of China (Grant No.U20A2049)the Key Research and Development Program of Zhejiang Province (Grant No.2021C02001)the Scienti?c Research Startup Fund Project of Zhejiang A&F University (Grant No.2022LFR033)。
文摘Torreya grandis is a characteristic rare economic tree species in subtropical mountainous areas. The nut has a variety of bioactive compounds, such as polyphenols and vitamins. However, the carotenoids compositions and its regulatory mechanisms underlying carotenoid biosynthesis in kernels remain unknown. Here, the major carotenoids in the kernel were analyzed. The result showed that lutein and β-carotene were the predominant carotenoids in the kernel, while low levels of a-carotenoid and zeaxanthin were detected. Lutein and β-carotene were decreased during the maturation of kernel. Expression analysis by RNA-seq and q RT-PCR indicated that the expressions of TgCYP97A3 and TgLCYB were also reduced during the maturation of kernel. The contents of lutein or β-carotene were obviously increased in tobacco transiently overexpressing TgCYP97A3 or TgLCYB. Moreover, DPPH radical scavenging activity and FRAP were also significantly enhanced. In addition, several MYB and WRKY transcription factors TgMYBS3, TgMYB48 and TgWRKY11 were identified to positively regulate the TgCYP97A3 expression, while TgMYB48, TgWRKY2 and TgWRKY11 could upregulate the TgLCYB expression. The illustration of carotenoids biosynthesis and its molecular mechanism in kernels not only provides a basis for understanding carotenoids biosynthesis in kernels, but also enables the use of molecular biotechnology to develop new health products rich in carotenoids based on T. grandis nuts.
基金funded by the National Key Research and Development Program(grant number 2017YFD0601100)。
文摘Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils.Here we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation.The Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope position.The results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere soils.The lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in leaves.Nutrient accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils.Leaf C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope position.The contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively lower.Variations in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere soils.Chemical properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper slope.Correspondingly,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing factor.Overall,these results offer new insights for the sustainability and management of teak plantations in hilly areas.
基金funded by the National Nature Science Foundation of China (No.32171775,31770671)。
文摘Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely unclear.In this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with age.Seven phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere soils.Most of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years old.The concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in age.Notably,phenolic compounds contributed more to the variation in the understory plants than soil factors.Hydroxyphenyllactic acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation age.These findings indicate that young E.grandis plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential.
文摘Stains are applied to impart contrast to the tissue and identify particular features of interest. However, the use of synthetic dyes as staining reagents has been associated with significant human health challenges and pollution of the ecosystem. These developments have necessitated a shift towards using natural dyes that are eco-friendlier and readily available. We investigated the staining reaction patterns of teak tree leaves (Tectona grandis) dye extracts and explored their suitability as a cytoplasmic stain in micromorphological assessments. Dye extracts were prepared using acetone, methanol, and ethanol as solvents from air-dried (under shade) teak tree young leaves. The dye extracts were applied as a counterstain and evaluated against eosin in formalin-fixed paraffin-embedded (FFPE) bovine tissue sections at varying concentrations and different staining times. Teak tree leaves (Tectona grandis) dye extracts produced relatively varying staining intensities of reddish-brown cytoplasmic coloration when used on bovine tissue at different concentrations and staining times comparable to eosin and with blue-purple hematoxylin nuclear stain. The present study showed that Tectona grandis leaf dye extracts provide an excellent cytoplasmic staining pattern and can be used as an alternative counterstain in routine H&E staining techniques.
基金Supported by Youth Project of Natural Science Foundation of Anhui Province(2008085QC134)Natural Science Research Project in Colleges and Universities in Anhui Province(KJHS2019B09)+2 种基金School-level Talent Start-up Project(2020xkjq009)Key Project of Anhui Provincial Department of Education(2023AH051375)Key Project of Natural Science Research of Anhui Provincial Department of Education(KJ2020A0691).
文摘[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis.
基金Supported by Sichuan Science and Technology Plan Project(2014NZ0033)~~
文摘This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: (1) The distribution of ma- jor nutrient element contents in various organs of the E. grandis with the 2 densi- ties was nearly the same, and the ranked order was leaf〉tree trunk〉branch or branchlet〉fruit〉bark. (2) From the distribution of nutrient elements and organic mat- ter in the trunk, P, K, Mg and Ca contents presented basically a trend of increasing with the trunk height increasing. And the organic matter content increased with the trunk height increasing in the low density stand, while the result was opposite in the high density stand. Furthermore, N content increased with the trunk height increas- ing in the low density stand, but the content in the high density stand exhibited a trend of decreasing at first, increasing then and increasing at the last. (3) From the distribution of biomass, the ranked order was tree trunk〉bark or branch〉branchlet〉 leaf〉fruit. And (4) The accumulated amounts of major nutrient elements in various organs under the 2 stand densities was nearly same. Ca content was the highest in the 2 kinds of plantations, followed by N, K, Mg and P contents. Ca content was 601.78 kg/hm2 in the low density stand and 1 204. 43 kg/hm2 in the high density stand.
基金Supported by the Key Laboratory of Forest Ecology and Resource Environment of Sichuan Province~~
文摘The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of nutrient elements varied greatly in different organs. Total contents of macroelements N, P, K, Ca and Mg in1a-3a E. grandis were distributed in the order of stem phloem, leaves 〉 branch- es, roots 〉 stem xylem. Accumulated amount of macroelements in 1a-3a E. grandis were in the order of leaves 〉 branches 〉 stem phloem 〉 roots or stem xylem 〉 stem xylem or roots. Accumulated amount law of nutrient elements was not affected by the plant age. Microelements Fe and Zn were mainly concentrated in the leaves and roots. The accumulation of macroelements was in the order of Ca 〉 N 〉 K 〉 Mg 〉 P; and the microelements was in the order of Fe 〉 Zn. Accumulated amounts of microelements in 1a-3a E. grandis were 12.45 136.19 and 420.23 g per plants, respectively. Among the annual net accumulated amount of nutrient ele- ments per plant in 1a-3a E. grandis, Ca element was the maximum, N and K ele- ments took the second and third places. Mg element was relatively small and P el- ement was the minimum.
基金Supported by Key Science and Technology Project of Forestry in Guangxi Province for the Eleventh Five-year Plan ([2009] No.8)~~
文摘[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis×E.urophylla were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×E.urophylla both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×E.urophylla both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species.
基金canara bank, Zamin uthukuli for the financial supports
文摘Objective:To investigate antidiabetic,antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis(T.grandis) flowers(METGF) in streplozotocin(STZ) induced diabetic rats to supports its traditional use.Methods:Acute toxicity study of METGF was carried out in rat to determine its dose for the antidiabetic study.Oral glucose tolerance test(OGTT) was performed to evaluate METGF effect on elevated blood glucose level.Diabetes was induced in rats by administration of STZ(60 mg/kg,ip.) and it was confirmed 72 h after induction.METGF was orally given to the diabetic rats up to 28 days and blood glucose level were estimated each week.On 28 day of the experiment,diabetic rats were sacrificed after the blood collection for the biochemical parameters analysis and liver,kidney was collected to determine antioxidants levels.Results: In acute toxicity,METGF did not show toxicity and death up to a dose 2 000 mg/kg in rats. Administration of METGF 100 and 200 mg/kg significantly(P【0.001) reduced blood glucose levels in OGTT and STZ-induced diabetic rats.Both doses of METGF treatment significantly(P【0.001, P【0.01 and P【0.05) increased body weight,serum insulin,haemoglobin(Hb) and total protein levels in diabetic rats.Also,MEGTF treatment reduced elevated glycosylated haemoglobin(HbA1c) and other biochemical parameters levels significantly(P【0.001) in diabetic rats.Altered lipid profiles and antioxidants levels were reversed to near normal in diabetic rats treated with METGF. Conclusions:These results concluded that METGF possesses antidiabetic,antihyperglycemic and antioxidant activity which supports its traditional use.