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1.
Li-Qing XIAO Ai-Hua LIU and Yong-Lian ZHANG State Key Laboratory of Molecular Biology Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Shanghai China 《Acta biochimica et biophysica Sinica》2004,(8)
Defensins are a family of evolutionarily relatedvertebrate antimicrobial peptides with a characteristicβ-sheet-rich fold and a framework of six disulphide-linkedcysteines. The two main defensin subfamilies, α- andβ-defensin, differ in the length of pep… 相似文献
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Alien DNA introgression and wheat DNA rearrangements in a stable wheat line derived from the early generation of distant hybridization 总被引:2,自引:0,他引:2
ZHANG Lianquan LIU Dengcai YAN Zehong & ZHENG Youliang Triticeae Research Institute Sichuan Agricultural University Dujiangyan China 《中国科学:生命科学英文版》2005,48(5):424-433
In general, it requires five or more generations to develop a stable line by the traditional breeding method of cultivar hybrids in self-pollinated crops, such as wheat, barley, and rice. No doubt, the breeding period will be shortened and thus the breeding effi-ciency will be improved if the hybrids can stabilize in early generation. The method of haploid breeding, that is, obtaining stable pure lines (DH lines) of cultivar hybrids with the aid of anther culture and then chro-mosome doubling,… 相似文献
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REN Yuanyuan DAI Xiuyu ZHOU Jian LIU Jingfang PEI Huadong & XIANG Hua . State Key Laboratory of Microbial Resources Center for Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Beijing China . Graduate School of Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):221-227
Trehalose is a non-reducing disaccharide of glucosewidely distributed in microorganisms, plants and in-sects. It usually functions as a compatible solute in thestabilization of biological structures under several en-vironment stresses[1,2]. Trehalose has proved to be anactive stabilizer of enzymes, proteins, biomasses, pharmaceutical preparations and even organs fortransplantation. Thus much attention has been paid tothe synthesis pathway of trehalose and the develop-ment of novel and economic… 相似文献
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Study of the tolerance of Hippochaete ramosissimum to Cu stress 总被引:1,自引:0,他引:1
LIU Dengyi LI Ying CHU Ling WANG Guanglin & WANG Lilong Biodiversity Research Center Anhui Normal University Wuhu China The Provincial Key Laboratory of Conservation Exploitation of Biological Resources in Anhui Wuhu China 《中国科学:生命科学英文版》2005,48(Z1)
We investigated the tolerance of Hippochaete ramosissimum and the changes in physiological metabolism following exposure to copper using pot experiments and analyzing plant physiology and biochemistry. The results showed that Cu tolerance in Hippochaete ramosissimum varied significantly between different populations; the tolerance of plants living in Cu polluted areas for extended periods of time exceeded that of plants living in unpolluted areas. SOD and POD activities in highly Cu tolerant plants increased noticeably following exposure to Cu. This indicates that maintaining and increasing the two kinds of protective enzyme activities are the primary foundations of plant tolerance. However, no change in CAT activity was demonstrated following Cu exposure. In summary, there existed considerable differences in physiological metabolism between different populations of Hippochaete ramosissimum following exposure to Cu. 相似文献
8.
Jun-Huan ZHANG Wei-Dong HUANG Yue-Ping LIU Qiu-Hong PAN 《植物学报(英文版)》2005,47(8):959-970
Leaves from annual young grape plants (Vitis vinifera L. cv. Jingxiu) were used as experimental materials. The ultrastructural characteristics of mesophyll cells in chilling-treated plants after heat acclimation (HA) and in heat-treated plants after cold acclimation (CA) were observed and compared using transmission electron microscopy. The results showed that slight injury appeared in the ultrastructure of mesophyll cells after either HA (38℃ for 10 h) or CA (8℃ for 2.5 d), but the tolerance to subsequent extreme temperature stress was remarkably improved by HA or CA pretreatment. The increases in membrane permeability and malondialdehyde concentration under chilling (0℃) or heat (45℃) stress were markedly inhibited by HA or CA pretreatment. The mesophyll cells of plants not pretreated with HA were markedly damaged following chilling stress. The chloroplasts appeared irregular in shape, the arrangement of the stroma lamellae was disordered, and no starch granules were present. The cristae of the mitochondria were disrupted and became empty. The nucleus became irregular in shape and the nuclear membrane was digested. In contrast, the mesophyll cells of HA-pretreated plants maintained an intact ultrastructure under chilling stress. The mesophyll cells of control plants were also severely damaged under heat stress. The chloroplast became round in shape, the stroma lamellae became swollen, and the contents of vacuoles formed clumps. In the case of mitochondria of control plants subjected to heat stress, the outer envelope was digested and the cristae were disrupted and became many small vesicles. Compared with cellular organelles in control plants, those in CA plant cells always maintained an integrated state during whole heat stress, except for the chloroplasts, which became round in shape after 10 h heat stress. From these data, we suggest that the stability of mesophyll cells under chilling stress can be increased by HA pretreatment. Similarly, CA pretreatment can protect chloroplasts, mitochondria, and the nucleus against subsequent heat stress; thus, the thermoresistance of grape seedlings was improved. The results obtained in the present study are the first, to our knowledge, to offered cytological evidence of cross-adaptation to temperature stresses in grape plants. 相似文献
9.
Population dynamics of the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) in the Kunming area,southwestern China 总被引:5,自引:0,他引:5
HUI YE JIAN-HONG LIU 《Insect Science》2005,12(5):387-392
Population dynamics of Bactrocera dorsalis Hendel (Diptera: Tephritidae) were studied through pheromone trapping over 4 years (1997, 1999, 2000, 2003) in the Kunming region, a high plateau area in southwestern China. B. dorsalis immigrates from southern Yunnan to Kunming each year, and occurs during early May through November. Annual trap captures recorded an increase in the B. dorsalis populations from May to July, when they peaked in abundance, and a decline until November. No flies were detected from November to April. The fruit flies had two generations. There was considerable overlapping due to the continuous arrival of immigrating flies during the summer months. Annual capture rates were significantly related to numbers of flies caught in July when peak captures were recorded; whereas the peak captures, in turn, positively depended on numbers of flies recorded in May, the first month of fly appearance in the current year. It suggested that the annual population abundance was mainly dependent on the size of the initial emigrating population. A daily average temperature of 18℃ was probably the threshold temperature required for the flies to undertake long-range dispersal, which partially explained the start of the fly in May each year on this high plateau. Under field conditions, the fruit flies can withstand 13℃ as a daily average temperature. No flies were recorded in any of the study years at a daily temperature colder than 10 ℃. 相似文献
10.
Mapping of a Wheat Resistance Gene to Yellow Mosaic Disease by Amplified Fragment Length Polymorphism and Simple Sequence Repeat Markers 总被引:3,自引:0,他引:3
Wei-Hua LIU Huan NIE Zhen-Tian HE Xiu-Lan CHEN Yue-Peng HAN Jin-Rong WANG Xin LI Cheng-Gui HAN Jia-Lin YU 《植物学报(英文版)》2005,47(9):1133-1139
Wheat (Triticum aestivum L.) yellow mosaic virus (WYMV) is transmitted by a fungal vector through soil and causes serious wheat yield losses due to yellow mosaic disease, with yellow-streaked leaves and stunted plants. In the present study, the amplified fragment length polymorphisms (AFLP) and simple sequence repeat (SSR) were used to identify the molecular linkages with the resistance gene against WYMV. Bulked segregant analysis was performed with an F2 population derived from the cross of cultivar Ningmai 9 (resistant) × cultivar Yangmai 10 (susceptible). By screening among the resistant or susceptible parents, the F2 pools and the individuals in the F2 population with 64 combined selective AFLP primers (EcoRI/MseI) or 290 reported SSR primers, a polymorphic DNA segment (approximately 120 bp) was amplified using the primer pair E2/M5, and an SSR marker (approximately 180 bp) was located on wheat chromosome 2A using the primer Xgwm328. Analysis with MAPMAKER/Exp Version 3.0b (Whitehead institute for Biomedical Research, Cambridge, MA, USA) indicated that these two markers were dominantly associated with the resistance gene at distances of 5.4 cM or 17.6 cM, respectively. The resistance gene to WYMV derived from Ningmai 9, is temporarily named YmNM, and was mapped to wheat chromosome 2A. 相似文献