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Dry Matter Accumulation,Moisture Content in Maize Kernel and Their Influences on Mechanical Harvesting 被引量:17
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作者 阮龙 王俊 +4 位作者 陈义红 王世济 张玮 左晓龙 陈洪俭 《Agricultural Science & Technology》 CAS 2011年第12期1857-1860,共4页
[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu... [Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index(kernel loss rate of 0.84%≤2%),while the percentage of broken kernels did not accord with the range of mechanical operation index(kernel crashing rate of 10.12%≧1%).The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting. 展开更多
关键词 Maize(Zea mays) Kernel weight Moisture content Physiological mature stage
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Reproductive Cycle and Seasonal Variations in Lipid Content and Fatty Acid Composition in Gonad of the Cockle Fulvia mutica in Relation to Temperature and Food 被引量:3
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作者 LIU Wenguang LI Qi KONG Lingfeng 《Journal of Ocean University of China》 SCIE CAS 2013年第3期427-433,共7页
From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive c... From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica. 展开更多
关键词 Fulvia mutica LIPIDS fatty acids reproductive cycle FOOD TEMPERATURE
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Study of Synthetic Process of Vitamin C
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作者 WANG Jing-chen CUI Feng-xia REN Bao-zeng 《Chinese Food Science》 2012年第2期8-10,共3页
[ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination... [ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination, recovery and purification. The impact of reaction time, tempera-ture, feedstock molar ratio and water content on the yield of vitamin C were investigated in the experiment. [Result] The optimum reaction condi- tions for synthetic process of Vitamin C were as follows: in the acidification test, reaction time 120 min, temperature 20 -30 ℃, the molar ratio be-tween hydrochloric acid and Vitamin C sodium 1 : 1 and water content 41.0%. Under the above condition, the purity and yield of vitamin C reach 99.80% and 94.74% respectively. [Conclusion] The process can decrease consumption, enhance quality and recover of the product, improve the environmental pollution, shorten processing periods and reduce production cost. Thus, the process is suitable for industrialization. Key words Vitamin C; Vitamin C sodium; Acidification; China 展开更多
关键词 Vitamin C Vitamin C sodium ACIDIFICATION China
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Enhancing Biogas Production from Anaerobically Digested Wheat Straw Through Ammonia Pretreatment 被引量:4
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作者 杨懂艳 庞云芝 +4 位作者 袁海荣 陈树林 马晶伟 郁亮 李秀金 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第5期576-582,共7页
Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(... Aqueous ammonia was used to pretreat wheat straw to improve biodegradability and provide nitrogen source for enhancing biogas production. Three doses of ammonia(2%, 4%, and 6%, dry matter) and three moisture contents(30%, 60%, and 80%, dry matter) were applied to pretreat wheat straw for 7 days. The pretreated wheat straws were anaerobically digested at three loading rates(50, 65, and 80 g·L-1) to produce biogas. The results indicated that the wheat straw pretreated with 80% moisture content and 4% ammonia achieved the highest methane yield of 199.7 ml·g-1(based on per unit volatile solids loaded), with shorter digestion time(T80) of 25 days at the loading rate of 65 g·L-1compared to untreated one. The main chemical compositions of wheat straw were also analyzed. The cellulose and hemicellulose contents were decomposed by 2%-20% and 26%-42%, respectively,while the lignin content was hardly removed, cold-water and hot-water extracts were increased by 4%-44%, and12%-52%, respectively, for the ammonia-pretreated wheat straws at different moisture contents. The appropriate C/N ratio and decomposition of original chemical compositions into relatively readily biodegradable substances will improve the biodegradability and biogas yield. 展开更多
关键词 wheat straw anaerobic digestion BIOGAS ammonia pretreatment moisture content
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Chemical Composition of Potato Tubers in Relation to Crop Production System and Environmental Conditions
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作者 Krystyna Zarzynska 《Journal of Agricultural Science and Technology(B)》 2013年第10期689-695,共7页
In the years 2008-2010, a study on the quality of tubers grown in the two crop production systems, i.e., organic and integrated in two locations: Jadwisin--Central and Osiny--South-Eastern of Poland were conducted. T... In the years 2008-2010, a study on the quality of tubers grown in the two crop production systems, i.e., organic and integrated in two locations: Jadwisin--Central and Osiny--South-Eastern of Poland were conducted. The influence of such factors as the crop production system (organic and integrated), the place of production (soil quality), variety and years of research on the chemical composition, i.e., tuber dry matter, starch, vitamin C, nitrates and glycoalkaloids were tested. It has been found that the greatest impact on the chemical composition of tubers had the climatic conditions during the growing season and genotype. They affected the contents of all tested components. The place of production affected the contents of dry matter, starch, vitamin C and nitrates. This factor had no effect on the content of glycoalkaloids. The least effect on the chemical tubers composition was in crop production system. It only affected the contents of dry matter, starch and vitamin C. There was no significant effect of this factor on the nitrate and glycoalkaloids content. 展开更多
关键词 POTATO TUBER chemical composition crop production system cultivar.
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Chemical Variation in Essential Oils of Salvia Officmalis L, Ecotypes Cultivated in Albania
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作者 Elvira Bazina 《Journal of Life Sciences》 2015年第3期95-102,共8页
Salvia officinalis L. was cultivated in different geographic locations of Albania. Sage plants originated from imported seeds and wild Albanian plants. Around 30 chemical compounds were identified in the essential oil... Salvia officinalis L. was cultivated in different geographic locations of Albania. Sage plants originated from imported seeds and wild Albanian plants. Around 30 chemical compounds were identified in the essential oils of all cultivated sage plants; the latter were found to be very rich in camphen, fl-thujone, a-pinene, eucaliptol, rich to moderate in β-pinene and camphor, and less rich in a-thujone and limonene. Sharp differences in chemical composition patterns and content of individual chemical compounds were noticed between and within cultivation sites. Cultivated sage was poorer in α-thujone versus wild plants. Cultivated sage, of Albanian wild plants origin, was the richest in α-thujone (18.45%) versus imported seeds sage. β-thujone over-dominated α-thujone in all cultivated sage plants. Volatile characters of cultivated sage were indicative of the species but not of the geographic origin of plant material. Variation in essential oils composition and chemical compounds' content (biosynthetic pathways) in cultivated sage is related more to the genetic background than the environmental factors. If cultivating sage in Albania, then wild local ecotypes would be best to use as α-thujone is maintained at satisfactory levels, local natural base is preserved, unnecessary hybridization with imported seeds sage is prevented, and are more resistant and cost effective. 展开更多
关键词 SAGE Headspace-GC/MC chemical composition variation cultivation.
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Proximate Composition Determination and Sensory Evaluation of "Donkwa" Produced from a Blend of Tigernuts and Groundnut
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作者 Johnson Akinwumi Adejuyitan Ezekiel Tejumola Otunola Sogo James Olatunde Bosede Feyisetan Babatunde 《Journal of Agricultural Science and Technology(B)》 2014年第7期581-585,共5页
The effect of preparing "donkwa" from a blend of tigernut and groundnut at different proportion (90:10, 80:20, 70:30 and 50:50 (tigernut:groundnut)) was evaluated on the proximate composition and sensory qu... The effect of preparing "donkwa" from a blend of tigernut and groundnut at different proportion (90:10, 80:20, 70:30 and 50:50 (tigernut:groundnut)) was evaluated on the proximate composition and sensory qualities. This was compared with a sample of "donkwa" prepared by the popular method from a blend of maize and groundnut. The results revealed the protein content range of 21.84%-23.67% with tigernut based "donkwa", while the protein content of maize based "donkwa" was 21.60% at 50:50 (maize:groundnut) ratio. The highest value was also recorded for fiber content with maize based "donkwa" (50:50) which was 3.63% with no significant difference from the value obtained from tigernut based "donkwa" at 90:10 (tigernut:groundnut) ratio which was 3.25%. The sensory qualities revealed that the tigernut based "donkwa" compared favourably with the maize based "donkwa" with indication that there was no significant difference in terms of colour among the samples. There was significant difference among the samples in terms of taste, texture, flavour and general acceptability with the maize based "donkwa" most preffered in terms texture and general acceptability. In conclusion, the results obtained show the possibility of preparing "donkwa" from tigernut to give a nutritious and highly acceptable product. 展开更多
关键词 Tigernut utilization MAIZE donkwa SNACKS proximate composition acceptability.
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Annual Component Analysis of Pacific Oysters (Crassostrea gigas) and Mussels (Mytilus gallopro vincialis)
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作者 Yumiko Yoshiki Chiho Mizukoshi Uno Masatoshi 《Journal of Shipping and Ocean Engineering》 2014年第7期203-213,共11页
To study the change in components of Pacific oysters (Crassostrea gigas) and mussels (Mytilus galloprovincialis) over a year, their annual obesity ratio, umami components (glutamic acid and glycogen), functional... To study the change in components of Pacific oysters (Crassostrea gigas) and mussels (Mytilus galloprovincialis) over a year, their annual obesity ratio, umami components (glutamic acid and glycogen), functional components (Zn, Mn, Cu, and vitamin B12), and Cd and noroviruses (NoVs) contents were quantified. In oysters, the obesity ratio and chemical components showed seasonal changes depending on the spawning season. Glutamic acid content increased from November to March. In contrast, glycogen content peaked in May and November. Mineral content markedly increased during spawning. From the comparison of NoVs GI and GII strains, oyster predominately infected by the GI. A remarkable difference in NoVs contents was observed depending on the oyster farms. In mussels, glutamic acid, Zn and Cu contents were stable throughout the year. Mussels' Cd content was about one-fifths times lower than that found in oysters. Although the NoVs strain was affected by the collection area, mussels from both areas showed decreased NoVs contents in summer, corresponding with the consumption season of mussels in Japan. Our comparative study on the seasonal variability in the chemical components and NoVs contents in pacific oysters (C. gigas) and mussels (M. galloprovincialis) clearly showed an association with physiological and environmental factors. 展开更多
关键词 OYSTER MUSSEL seasonal variation mineral norovirus.
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Classification of Thai Honey Origins by Their Mineral Contents and Color Parameters
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作者 Nongnuch Tantidanai-Sungayuth Jitranut Leewatchararongjaroen Pitiporn Ritthiruangdej 《Journal of Agricultural Science and Technology(B)》 2012年第6期678-690,共13页
Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red... Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red color, b*: yellow color, C*ab and hab) and five elements (Na, K, Mg, Ca and Zn) were determined and related with 91 Thai honey samples. The origins of four botanic types of (1) longan flower (Dimocarpus sp.), (2) lynchee flower (Litchi sp.), (3) sunflower (Helianthus sp.) and (4) wild flower (Eupatorium sp.) using principle component analysis (PCA). The results showed that five color parameters and five metal contents related with the Thai botanic origins of the honeys using principle component analysis (PCA). Six major indicators of PC i (variance is 44.33%) from three color parameters are L*(-0.926), a*(0.927) and hue or hab (0.824) and from three metal contents are K(0.833), Ca(0.816) and Mg(0.595). Two minor indicators of PC2 (variance is 21.58%) from color parameters are b*(-0.934) and Chroma or C*ab (-0.834). Two indicators of PC3 (%variance is 12.47%) from contents of Na (-0.722) and Zn (0.704). Thai Lynchee (C) flower honeys classified using both six parameters in PC 1 and two color parameters in PC2. Thai longan flower (G) honeys classified using the contents of Zn and Na in PC3 parameters. Thai sunflower (S) honeys classified using two color parameters in PC2. Thai wild flower (W) honeys classified using the metal contents of K in PC 1 parameter, Zn and Na in PC3 parameters. 展开更多
关键词 Minerals metals Thai honey botanic origins Lynchee (Lichi sp.) sun flower (Helianthus sp.) longan (Dimocarpus sp.) PCA.
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Effects of Plant Population on Growth, Development and Oil Yield of Safflower
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作者 Vallantino Emongor Otsoseng Oagile Boipuso Kedikanetswe 《Journal of Agricultural Science and Technology(B)》 2013年第5期321-333,共13页
Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects ... Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential. 展开更多
关键词 Safflower (Carthamus tinctorius L.) plant density vegetative growth yield and yield components oil content.
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Plant Response and Grape Composition of Vitis vinifera L, cv Tannat in Different Climatic Regions
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作者 Milka Ferrer Gustavo Gonzalez-Nevest +1 位作者 Gerardo Echeverria Gianfranca Camussi 《Journal of Agricultural Science and Technology(B)》 2012年第12期1252-1261,共10页
In wine production, the typical characteristics of variety, defined by its place of their origin, contribute to the development of distinctive and unique wines. In the current study, we analyzed the effect of the envi... In wine production, the typical characteristics of variety, defined by its place of their origin, contribute to the development of distinctive and unique wines. In the current study, we analyzed the effect of the environment using vine response and grape composition as indicators. Four cv. Tannat vineyards in three different climatic regions of Uruguay with similar soil conditions were studied in 2008 and 2009. Vines grafted onto SO4 (Vitis berlandieri × Vitis riparia) rootstock and were trained on a trellis system. Weather information was obtained from weather stations (MMO standards). At each vineyard, we recorded: yield per plant, pruning weight, leaf area and pre-dawn leaf water potential. We analyzed sugars, total acidity and pH, polyphenolic potential, organic acids and berry weight. Analysis of variance, Pearson correlations and discriminant analysis were carried out. The climate factors with the highest discriminant weight were water balance, degree days (〉 10 ℃) of maturation and rainfall during the vegetative growth period. Plant response allowed us to discriminate between vineyards regardless of the year and was consistent with climate. Exposed leaf area and length of maturation period were the indexes with the highest values, followed by leaf water potential and grape yield. The total anthocyanin content, sugar contents and their daily accumulation, and acid composition statistically separate regions regardless of the year. We concluded that plant response and grape composition were strongly influenced by water supply and thermal conditions during ripening. 展开更多
关键词 Environmental factors vine behavior grape composition Tannat.
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植物油反式脂肪酸形成途径及调控研究进展
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作者 梁蔓竹 胡雨萌 +4 位作者 李振源 黄雪港 BELLO Zaki Abubakar 郭芹 王强 《食品科学》 EI CAS 2024年第23期329-337,共9页
反式脂肪酸(trans fatty acids,TFAs)对人体健康的危害已经引起各界高度关注,而植物油是人们日常摄入TFAs的主要来源,了解植物油TFAs形成以实现其精准调控至关重要。近年来,有研究对TFAs在不同植物油中的生成含量进行探究,以及在不同TFA... 反式脂肪酸(trans fatty acids,TFAs)对人体健康的危害已经引起各界高度关注,而植物油是人们日常摄入TFAs的主要来源,了解植物油TFAs形成以实现其精准调控至关重要。近年来,有研究对TFAs在不同植物油中的生成含量进行探究,以及在不同TFAs异构体形成途径及调控机理方面也取得了突破性进展,但鲜有进行系统全面的综述。本文主要从不同种植物油TFAs种类和含量、形成机理、调控措施及调控机理等方面进行系统梳理,以期为人们日常植物油TFAs摄入以及植物油TFAs后续研究提供参考。 展开更多
关键词 反式脂肪酸 植物油 形成机理 控制方法 生成含量
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Simultaneous determination of Saikosaponin a, c and d in different parts of wild bupleurum from Shanxi Province 被引量:8
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作者 Rui Wang Ximei Yuan +2 位作者 Boya Ju Rui Liu Hongxia Yuan 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2018年第10期703-710,共8页
As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri(Chai-Hu) is commonly used for the treatment of influenza,which is derived from the dried root... As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri(Chai-Hu) is commonly used for the treatment of influenza,which is derived from the dried roots of Bupleurum chinense DC.and Bupleurum scorzonerifolium Willd.Among of diverse chemical components,saikosaponins are the key active components of the herb medicine.In the present study,we established a method of high performance liquid chromatography(HPLC) coupled with evaporative light scattering detection(ELSD) for simultaneous determination of saikosaponin a,c and d in root,stem,leaf and flower of Bupleurum chinense(B chinense) collected from different areas of Shanxi Province,China.The results from 16 samples of root,stem,leaf and flower of B chinense demonstrated that the total contents of the three saikosaponins in the root of B chinense collected from Dongshan Taiyuan,Xishan,Tianlongshan and Pangquangou were 4.26 mg/g,3.22 mg/g,4.23 mg/g and 3.05 mg/g,respectively.However,there was scarcely any saikosaponins in the stem,leaf and flower of B chinense collected from above-mentioned areas.The method of HPLC coupled with ELSD was suitable for quality control of Radix Bupleuri.The result also confirmed that the root of B chinense was the best medicinal part. 展开更多
关键词 Bupleurum chinense DC. Different parts SAIKOSAPONINS Content analysis
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Phytosterol content and the campesterol:sitosterol ratio influence cotton fiber development: role of phytosterols in cell elongation 被引量:6
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作者 Shasha Deng Ting Wei +8 位作者 Kunling Tan Mingyu Hu Fang Li Yunlan Zhai Shue Ye Yuehua Xiao Lei Hou Yan Pei Ming Luo 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第2期183-193,共11页
Phytosterols play an important role in plant growth and development, including cell division, cell elongation, embryogenesis, cellulose biosynthesis, and cell wall formation. Cotton fiber, which undergoes synchronous ... Phytosterols play an important role in plant growth and development, including cell division, cell elongation, embryogenesis, cellulose biosynthesis, and cell wall formation. Cotton fiber, which undergoes synchronous cell elongation and a large amount of cellulose synthesis, is an ideal model for the study of plant cell elongation and cell wall biogenesis. The role of phytosterols in fiber growth was investigated by treating the fibers with tfidemorph, a sterol biosynthetic inhibitor. The inhibition of phy- tosterol biosynthesis resulted in an apparent suppression of fiber elongation in vitro or in planta. The determination of phy- tosterol quantity indicated that sitosterol and campesterol were the major phytosterols in cotton fibers; moreover, higher con- centrations of these phytosterols were observed during the period of rapid elongation of fibers. Furthermore, the decrease and increase in campesterol:sitosterol ratio was associated with the increase and decease in speed of elongation, respectively, dur- ing the elongation stage. The increase in the ratio was associated with the transition from cell elongation to secondary cell wall synthesis. In addition, a number of phytosterol biosynthetic genes were down-regulated in the short fibers of ligon lintless-1 mutant, compared to its near-isogenic wild-type TM-1. These results demonstrated that phytosterols play a crucial role in cot- ton fiber development, and particularly in fiber elongation. 展开更多
关键词 cotton fiber phytosterols gene expression tridemorph ligon lintless-1
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Effects of ecological factors on secondary metabolites and inorganic elements of Scutellaria baicalensis and analysis of geoherblism 被引量:10
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作者 GUO LanPing WANG Sheng +8 位作者 ZHANG Ji YANG Guang ZHAO ManXi MA WeiFeng ZHANG XiaoBo LI Xuan HAN BangXing CHEN NaiFu HUANG LuQi 《Science China(Life Sciences)》 SCIE CAS 2013年第11期1047-1056,共10页
This study analyzed the effects of ecological factors on secondary metabolites of Scutellaria baicalensis using two sources:92individual roots of S.baicalensis from all over China,and secondary metabolites,medicinal m... This study analyzed the effects of ecological factors on secondary metabolites of Scutellaria baicalensis using two sources:92individual roots of S.baicalensis from all over China,and secondary metabolites,medicinal materials and inorganic element contents obtained from the testing of 92 S.baicalensis rhizosphere soil samples.The study used environmental data from the Genuine Medicinal Material Spatial Analysis Database.Most of the chemical constituents of S.baicalensis were negatively correlated to latitude and positively correlated to temperature;generally,the contents of 21 chemical constituents were higher at low latitudes than that at high latitudes.By gradual regression analysis,it was found that the content of baicalin in S.baicalensis was negatively correlated to latitude and generally the content of inorganic elements in soil was excessively high(excluding Mg and Ca),which has a negative effect on the accumulation of chemical constituents in S.baicalensis.Based on the cluster analysis of 21 constituents,S.baicalensis from different places of origin was divided into two groups,and S.baicalensis was not genuine only in a specific small region.Within the zone from Chifeng,Inner Mongolia to Taibai,Shaanxi is suitable for accumulation of secondary metabolites of S.baicalensis and such a zone represents a suitable distribution and potential genuine producing area. 展开更多
关键词 Scutellaria baicalensis ecological factors geoherbs Daodi-herbs geographical variation
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Impact of Land-Use Change on Soil Microbial Community Composition and Organic Carbon Content in the Dry Tropics 被引量:5
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作者 Chandra Mohan KUMAR Nandita GHOSHAL 《Pedosphere》 SCIE CAS CSCD 2017年第5期974-977,共4页
Restoration of forests poses a major challenge globally, particularly in the tropics, as the forests in these regions are more vulnerable to land-use change. We studied land-use change from natural forest(NF) to degra... Restoration of forests poses a major challenge globally, particularly in the tropics, as the forests in these regions are more vulnerable to land-use change. We studied land-use change from natural forest(NF) to degraded forest(DF), and subsequently to either Jatropha curcas plantation(JP) or agroecosystem(AG), in the dry tropics of Uttar Pradesh, India, with respect to its impacts on soil microbial community composition as indicated by phospholipid fatty acid(PLFA) biomarkers and soil organic carbon(SOC) content. The trend of bacterial PLFAs across all land-use types was in the order: NF > JP > DF> AG. In NF, there was dominance of gram-negative bacterial(G^-) PLFAs over the corresponding gram-positive bacterial(G^+) PLFAs. The levels of G^- PLFAs in AG and JP differed significantly from those in DF, whereas those of G^+ PLFAs were relatively similar in these three land-use types. Fungal PLFAs,however, followed a different trend: NF > JP > DF = AG. Total PLFAs, fungal/bacterial(F/B) PLFA ratio, and SOC content followed trends similar to that of bacterial PLFAs. Across all land-use types, there were strong positive relationships between SOC content and G-, bacterial, fungal, and total microbial PLFAs and F/B PLFA ratio. Compared with bacterial PLFAs, fungal PLFAs appeared to be more responsive to land-use change. The F/B PLFA ratio, fungal PLFAs, and bacterial PLFAs explained 91%, 94%,and 73% of the variability in SOC content, respectively. The higher F/B PLFA ratio in JP favored more soil C storage, leading to faster ecosystem recovery compared to either AG or DF. The F/B PLFA ratio could be used as an early indicator of ecosystem recovery in response to disturbance, particularly in relation to land-use change. 展开更多
关键词 ecosystem recovery fungal/bacterial ratio natural forest phospholipid fatty acid (PLFA) PLANTATION
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