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Search Results: 1 - 10 of 12471 matches for " Changyan Tian "
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Biological mechanism of controlling cotton aphid (Homoptera: aphididae) by the marginal alfalfa zone surrounding cotton field
Runzhi Zhang,Hongbin Liang,Changyan Tian,Guangxue Zhang
Chinese Science Bulletin , 2000, DOI: 10.1007/BF02909768
Abstract: At the beginning stage of cotton aphids (Aphis gossypii Glover) invading the cotton field, large numbers of insects have accumulated in the marginal alfalfa (Medicago sativa L.) zone surrounding it. They are 6.94 times (excluded natural enemies) as many as the aphids in cotton field. Most of these insects areTherioaphid maculata (Buckton), and occur in fields 10–15 d earlier than cotton aphids. Consequently, abundant natural enemies have bred in alfalfa zone when cotton aphids increase rapidly in cotton fields in the middle of June in Xinhe County, Xinjiang Autonomous Region. The total number of the major natural enemies, including Coccinellids, Chrysopids and Syphid flies in alfalfa zone, is 13.65 times that in cotton field within the same acreage of fields. At this period, it is very effective to force the natural enemies from the alfalfa zone into the nearby cotton field to control the rapid increase of cotton aphid population by cutting the alfalfa stands.
Arbuscular mycorrhizal associations in the Gurbantunggut Desert
Changyan Tian,Zhaoyong Shi,Zhichao Chen,Gu Feng
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-8218-8
Abstract: The plants in the Gurbantunggut Desert located in Xinjiang, China are drought adapted species and grow in generally nutrient-poor soils. A survey was conducted in the desert to determine the arbuscular mycorrhizal (AM) status associated with the desert plants which belong to 23 species from 11 families of annuals and perennials. Roots from all plants were examined for the presence of internal and external hyphae, vesicles and coils/arbuscules to determine the status and extent of mycorrhizal colonization. Of the plant species surveyed, 14 (61%) were found to form AM associations, 5 (22%) were possible AM colonized species, and 4 were non-mycorrhizal plants. The proportions of annuals and shrubs forming AM were significantly lower than those of perennials and herbs, respectively. Spore density varied from 5 to 21 per 20 g in soil of root zone. 14 AM fungal taxa in 3 genera were isolated and identified, 10 of which belonged to Glomus, 3 to Acaulospora, and 1 to Archaeospora. Glomus was the dominant genus in all genera identified. G. deserticola and G. etunicatum were the most common taxa isolated, with occurrence frequencies of 77.4% and 74.8%, and relative abundances of 14.4% and 15.5%, respectively.
Ability of multicellular salt glands in Tamarix species to secrete Na+ and K+ selectively
HaiYan Ma,ChangYan Tian,Gu Feng,JunFeng Yuan
Science China Life Sciences , 2011, DOI: 10.1007/s11427-011-4145-2
Abstract: The present study aimed to determine the mechanism of cation-selective secretion by multicellular salt glands. Using a hydroponic culture system, the secretion and accumulation of Na+ and K+ in Tamarix ramosissima and T. laxa under different salt stresses (NaCl, KCl and NaCl+KCl) were studied. Additionally, the effects of salt gland inhibitors (orthovanadate, Ba2+, ouabain, tetraethylammonium (TEA) and verapamil) on Na+ and K+ secretion and accumulation were examined. Treatment with NaCl (at 0–200 mmol L 1 levels) significantly increased Na+ secretion, whereas KCl treatment (at 0–200 mmol L 1 levels) significantly increased K+ secretion. The ratio of secretion to accumulation of Na+ was higher than that of K+. The changes in Na+ and K+ secretion differed after adding different ions into the single-salt solutions. Addition of NaCl to the KCl solution (at 100 mmol L 1 level, respectively) led to a significant decrease in K+ secretion rate, whereas addition of KCl to the NaCl solution (at 100 mmol L 1 level, respectively) had little impact on the Na+ secretion rate. These results indicated that Na+ secretion in Tamarix was highly selective. In addition, Na+ secretion was significantly inhibited by orthovanadate, ouabain, TEA and verapamil, and K+ secretion was significantly inhibited by ouabain, TEA and verapamil. The different impacts of orthovanadate on Na+ and K+ secretion might be the primary cause for the different Na+ and K+ secretion abilities of multicellular salt glands in Tamarix.
Models for calculating phreatic water evaporation on bare and Tamarix-vegetated lands
Shunjun Hu,Changyan Tian,Yudong Song,Xiaobing Chen,Yuetan Li
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-8206-z
Abstract: Groundwater is the main source of water consumption of natural vegetation in arid regions. It is an effective approach to study ecological water demand of natural vegetation by phreatic evaporation. In order to study the ecological water demand of Tarim river basin, based on the observation data of phreatic evaporation on bare lands at the Aksu Water Balance Experimental station from 1989 to 1996, by analyzing the relationship of phreatic evaporation, depth of phreatic surface and evaporation of water, taking the limit rate of phreatic evaporation as the control condition, and based on the objective law that the relation between phreatic evaporation and evaporation of water is nonlinear, we establish models for calculating phreatic evaporation on bare land, which can fully reflect the law of phreatic evaporation in the Tarim river basin. According to the data of depth of phreatic surface and soil moisture when pheratic level decline is caused just by evapotranspiration on Tamarix-vegetated land from 2003 to 2004, we calculate the amount of phreatic evapora-tion and set up models for calculating phreatic evaporation on Tamarix-vegetated land. Phreatic evaporation on bare land and Tamarix-vegetated land could be transformed each other by a Tamarix vegetation conversion coefficient. The test results show that the calculation accuracy of the models is high and the models are suitable for Tarim river basin.
Biological mechanism of controlling cotton aphid (Homoptera: aphididae) by the marginal alfalfa zone surrounding cotton field

ZHANG Runzhi,LIANG Hongbin,TIAN Changyan,ZHANG Guangxue,

科学通报(英文版) , 2000,
Abstract: At the beginning stage of cotton aphids (Aphis gossypii Glover) invading the cotton field, large numbers of insects have accumulated in the marginal alfalfa (Medicago sativa L.) zone surrounding it. They are 6.94 times (excluded natural enemies) as many as the aphids in cotton field. Most of these insects areTherioaphid maculata (Buckton), and occur in fields 10–15 d earlier than cotton aphids. Consequently, abundant natural enemies have bred in alfalfa zone when cotton aphids increase rapidly in cotton fields in the middle of June in Xinhe County, Xinjiang Autonomous Region. The total number of the major natural enemies, including Coccinellids, Chrysopids and Syphid flies in alfalfa zone, is 13.65 times that in cotton field within the same acreage of fields. At this period, it is very effective to force the natural enemies from the alfalfa zone into the nearby cotton field to control the rapid increase of cotton aphid population by cutting the alfalfa stands.
Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs
Zhaoyong Shi,Liyun Zhang,Gu Feng,Peter Christie,Changyan Tian,Xiaolin Li
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-8217-9
Abstract: The arbuscular mycorrhizal (AM) fungal status of the four most common ephemeral plant species, Chorispora tenella (Pall.) DC., Ceratocephalus testiculatus (Crantz) Bess., Eremopyrum orientale (L.) Jaub et. Spash and Veronica campylopoda Boiss growing in an area dominated by Tamarisk shrubs (Tamarix spp.) was investigated. Samples of the four ephemerals and their rhizosphere soils were collected from underneath and beyond the canopies of the Tamarisk shrubs. Plant mycorrhizal status and soil AM fungal spore densities and community structures were analyzed and compared under and beyond the shrub canopies. The mycorrhizal colonization rates of the ephemerals and spore densities in their corresponding rhizosphere soils were significantly lower under the shrub canopies than beyond. The number of AM fungal species under the shrubs (12) was also lower than beyond the canopies (19). When soil properties in the rhizospheres of the four ephemerals were examined, available N and P and total P, organic matter content, total salt content and electrical conductivity (EC) were all higher under the canopies than beyond. In contrast, soil available K and pH showed no such trend. A total of 21 AM fungal species were isolated from rhizosphere soils of the four ephemerals. Five belonged to Acaulospora, one to Archaeospora, thirteen to Glomus and two to Paraglomus. We conclude that the canopies of Tamarix spp. exerted some influence on the AM status of the ephemerals and on the AM fungal communities and some of the properties of their rhizosphere soils.
Theoretical analysis of the limiting rate of phreatic evaporation for aeolian sandy soil in Taklimakan Desert
ShunJun Hu,JiaQiang Lei,XinWen Xu,YuDong Song,ChangYan Tian,XiaoBin Chen,XiuChang Li
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-008-6014-3
Abstract: Phreatic evaporation is a great lose for shallow groundwater in the Taklimakan Desert. Given soil type and groundwater table, the limiting rate of phreatic evaporation is defined as the maximum of water transferred from groundwater to soil surface per unit time, which is a key parameter and control condition for phreatic evaporation model developing. The soil water characteristic curve for the aeolian sandy soil in the Taklimakan Desert was fitted with the least square method based on the formula of soil moisture characteristics curve proposed by Van Genuchten, using observed soil moisture and soil water suction data. The unsaturated hydraulic conductivity was determined by the instantaneous profile method in situ and the calculation formula for unsaturated hydraulic conductivity was established. According to the steady flow theory, the quasi-analytical solution of limiting rate of phreatic evaporation was derived on the basis of generalization of the formula of unsaturated hydraulic conductivity. The results show that the soil moisture characteristics in the Taklimakan Desert can be well described by Van Genuchten’s formula, and the limiting rate of phreatic evaporation declines by power function with the descending of groundwater table.
Chlorophyll in desiccated seeds of a euhalophyte, Suaeda physophora, and its significancy in plant adaptation to salinity during germination
Yang Li,ShiRong Zhang,Jie Song,ChenXi Wu,ChangYan Tian,Gu Feng
Science China Life Sciences , 2008, DOI: 10.1007/s11427-008-0055-3
Abstract: The seed cotyledons of a euhalophyte, Suaeda physophora, were found to be dark green. The pigment extracted from the cotyledons was proved to be chlorophyll for the absorption spectra curve of extracts the same as that for leaves. Photosynthetic oxygen-exchanging could be detected after the seeds were moistened for 6 h. Microstructure of organelles in cotyledons of ungerminated seeds was detected by transmission electron microscopy. Histochemical pigmentation was used to investigate the degree of damage on the membrane of radicles. A xerophyte, Haloxylon persicum, whose cotyledons of desiccated seeds also contain chlorophyll was used as a comparative species. The results showed that S. physophora maintained the ultra-structure of chloroplasts, the integrity of plasma membranes of radicles kept much better than that of H. persicum, which showed the great adaptability to salinity of the euhalophyte even at the seed-germination stage. Seeds were incubated in 0 and 700 mmol/L NaCl for 10 days in darkness at 20°C, then ungerminated seeds in NaCl solution were transferred to deionised water and reincubated for another 8 days and was recorded the germination recovery. Dry seeds moistened with deionised water germinated gradually in the dark and germination was maximal after 3 or 4 d. Seeds at 700 mmol/L NaCl for 10 d and transferred back to deionised water germinated abruptly, most seeds germinated in one day and photosynthesis was also detected. It is concluded that recovery germination of S. physophora ensured the seeds could germinate rapidly after salinity declines, for example under the mild but transitory favorable edaphic condition in early spring. Photosynthesis function in seeds might also promoted radicle growth and seedling establishment.
Influence of saline soil and sandy soil on growth and mineral constituents of common annual halophytes in Xinjiang
盐土和沙土对新疆常见一年生盐生植物生长和体内矿质组成的影响

ZHANG Ke,TIAN Changyan,LI Chunjian,
张科
,田长彦,李春俭

生态学报 , 2012,
Abstract: In this study, five common annual halophytes (Salicornia europaea, Suaeda acuminate, Petrosimonia sibirica, Salsola subcrassa, Kochia scoparia) in hungriness-oasis ecotone of south border region of Gurbantonggut Desert were grown in undisturbed saline soil and sandy soil, and their growth and mineral constituents in shoots were compared. The results showed that: 1) the pH value of the undisturbed saline soil was lower, while electrical conductivity and water content were significantly higher than those of the sandy soil in each of the soil layers from 0 to 100 cm in depth; 2) shoot dry weight (DW) of plants grown in the saline soil was 7 to 118 times higher than DW of plants grown in the sandy soil, and the root/shoot DW ratio of plants in the sandy soil was 2 to 6 times higher; 3) water contents in shoots of these annual halophytes ranged from 52% to 81%. The differences in shoot water content in the mid and low salt-resistant halophytes grown in both soils was significant (P<0.05), while that in the super salt-resistant halophytes grown in both soils were similar; 4) shoot N concentration of the 5 annual halophytes ranged from 11 to 34 g/kg and the higher the available N in soil, the higher the N concentration in shoots of these plants. Shoot P concentration ranged 1-4 g/kg. The correlations between the shoot P concentration and the available soil P were similar to that for N (except for S. europaeae). By contrast, shoot K concentration of the plants grown in sandy soil was higher than that of plants grown in saline soil, although K concentration in the 0-60 cm soil was higher in the saline soil than that in the sandy soil; 5) although the contents of the soluble Ca, Mg, Na, S and Cl in each layer of the soils from 0 to 100 cm in depth in saline soil were significantly higher than those in sandy soil, the ratios of the Na, Cl and S concentrations in shoots of plants grown in saline soil to those in sandy soil were far lower than those in the both soils, and even Ca and Mg concentrations in shoots of the plants grown in saline soil were equal or significantly lower than those in sandy soil. The results indicate that the saline soil significantly affects not only the growth of annual halophytes, but also the uptake and accumulation of the mineral nutrients by plants. The results could provide clues for the further studies on the adaptive mechanisms of halophytes to saline soil, and help select plant species for phytoremediation of saline soil.
Chlorophyll in desiccated seeds of a euhalophyte, Suaeda physophora, and its significancy in plant adaptation to salinity during germination

Yang Li,ShiRong Zhang,Jie Song,ChenXi Wu,ChangYan Tian,Gu Feng,

中国科学C辑(英文版) , 2008,
Abstract: The seed cotyledons of a euhalophyte, Suaeda physophora, were found to be dark green. The pigment extracted from the cotyledons was proved to be chlorophyll for the absorption spectra curve of extracts the same as that for leaves. Photosynthetic oxygen-exchanging could be detected after the seeds were moistened for 6 h. Microstructure of organelles in cotyledons of ungerminated seeds was detected by transmission electron microscopy. Histochemical pigmentation was used to investigate the degree of damage on the membrane of radicles. A xerophyte, Haloxylon persicum, whose cotyledons of desiccated seeds also contain chlorophyll was used as a comparative species. The results showed that S. physophora maintained the ultra-structure of chloroplasts, the integrity of plasma membranes of radicles kept much better than that of H. persicum, which showed the great adaptability to salinity of the euhalophyte even at the seed-germination stage. Seeds were incubated in 0 and 700 mmol/L NaCl for 10 days in darkness at 20°C, then ungerminated seeds in NaCl solution were transferred to deionised water and reincubated for another 8 days and was recorded the germination recovery. Dry seeds moistened with deionised water germinated gradually in the dark and germination was maximal after 3 or 4 d. Seeds at 700 mmol/L NaCl for 10 d and transferred back to deionised water germinated abruptly, most seeds germinated in one day and photosynthesis was also detected. It is concluded that recovery germination of S. physophora ensured the seeds could germinate rapidly after salinity declines, for example under the mild but transitory favorable edaphic condition in early spring. Photosynthesis function in seeds might also promoted radicle growth and seedling establishment. Contributed equally to this work Supported by the National Natural Science Foundation of China (Grant No. 30770341), Key Programs of Xinjiang Autonomous Region of China (Grant No. 200533124) and Chinese Scholarship Council.
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