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Characteristics and Warning Indexes of Rice Seeds Viability Loss During Storage at 45℃ Constant Temperature

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agricultural sciences in China 2002年第8期1卷 911-915页

作者： LU Xin-xiong and CHEN Xiao-ling(Key Laboratory for crop Germplasm and Biotechnology of agricultural Ministry, institute of crop Germplasm Resources, chinese academy of agricultural sciences, beijing 100081, P.R.China) Key Laboratory for crop Germplasm and Biotechnology of agricultural Ministry Institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

Seed aging characteristics of rice was investigated in this study. Seeds of 34 japonica rice (O-ryza sativa subsp. japonica) varieties were held at 451 constant temperature. Changes in seed viability and seed vigor during aging process were measured to study seed viability-losing characteristic and to determine warning index for seed viability loss. As a result, seed viability survival curves were obtained across different rice accessions at 45℃ constant temperature. The curves appeared to be contra-sigmoid survival curves. The loss of seed viability in the aging process consisted of two phases. The first phase took a long duration, in which the viability of vigorous seeds declined slowly. In the second phase, seed viability declined rapidly. It was obvious that seed viability declined inconsistently during storage. It also showed that seed germination was prolonged and the seedling was significantly weakened before the coming of the rapid declining phase of seed viability. These two parameters could be used to indicate seed quality during storage. The rate of compatibility of tests (RCT), coefficient of variation (CV), vigor of seedling, the day the seeds start to germinate could be used as warning indexes to indicate overall quality of a mass of accessions. These warning indexes could also be used in monitoring the viability of seeds stored in the seed genebank.

关键词： Seed viability-loss characteristics Warning indexes Seed viability monitoring Germplasm conservation

Pattern phenomena in an rf discharge dusty plasma system

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science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2, YE Maofu2 & WANG Long2 1. College of science, China agricultural University, beijing 100083, China 2. institute of Physics, chinese academy of sciences, beijing 100080, China 1. College of science China Agricultural University Beijing 100083 China 2. institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Progress of the Research on the Conservation of crop Germplasm Resources in China

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agricultural sciences in China 2003年第8期2卷 825-835页

作者： LU Xin-xiong and CHEN Xiao-ling(Key Laboratory of crop Germplasm and Biotechnology > Ministry of Agriculture/institute of crop Germplasm Resources , chinese academy of agricultural sciences , beijing 100081, P.R.China) Key Laboratory of crop Germplasm and Biotechnology Ministry of Agriculture/Institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

In the last 20 years, China has made considerable achievements in the conservation of crop germplasm resources. A network for crop germplasm conservation has been established by the end of 2002, which includes a national long-term seed genebank and its duplicated genebank, 8 national medium-term seed genebanks, 30 national field genebanks. 2 national in vitro genebanks, and 3 in situ conservation sites including 1 for wild soybean and 2 for wild rice. More than 334 000 crop germplasm accessions are currently stored in the national long-term genebank, covering 35 families, 192 genera and 712 species, which rank in the first place in the world. More than 43 000 accessions of vegetatively propagated crops and perennial crops covering more than 900 species are conserved in the national field genebanks. In addition, 2 300 accessions are stored in the national in vitro genebanks. This paper reviewed the latest advances of techniques for safety preservation of stored germplasm in seed genebank, ultra-dried seed storage and in vitro preservation in China and discussed current highlights in germplasm conservation.

关键词： crop germplasm resources Seed preservation Ultra-dry storage In vitro preservation Preservation techniques

Transcriptional profile in response to ionizing radiation at low dose in Deinococcus radiodurans

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Progress in Natural science:Materials International 2007年第5期17卷 529-536页

作者： Chen Huan, Xu Zhenjian , Tian Bing , Chen Weiwei , Hu Songnian and Hua Yuejin (institute of Nuclear-agricultural science, Zhejiang University, Hangzhou 310029, China James D. Watson institute of Genome sciences, Zhejiang University, Hangzhou 310008, China beijing institute of Genomics, chinese academy of sciences, beijing 101300, China) [a]institute of Nuclear-agricultural science Zhejiang University Hangzhou China [b]James D. Watson institute of Genome sciences Zhejiang University Hangzhou China [c]beijing institute of Genomics Chinese Academy of Sciences Beijing China

The genome-wide transcription profile of Deinococcus radiodurans cells was investigated after treatment with low dose irradiation (2 kGy). From the expression profile, we found that the process of DNA repair was induced in order, i.e. genes involved in base excision repair, nucleotide excision repair and single-strand annealing were induced immediately after ionizing radiation, and genes for recombination repair, including recA, recD and recQ were then activated. Especially, recD and recQ were specifically induced at low dose irradiation, and this phenomenon informed us that these two genes would play a certain role in anti-oxidation. Some genes such as ddrA and ssb were activated during the whole repair phase. Furthermore, the response of oxidative stress-related genes under low dose irradiation showed a different pattern from that of the acute high-level irradiation, many anti-oxidative genes were induced to scavenge reactive oxygen species directly, other associated systems also changed their expression patterns during the recovery time, such as iron metabolism systems, intracellular mutagenic precursors sanitize systems. These characteristics indicate that there is a powerful and orderly recovery process in Deinococcus radiodurans.

关键词： Deinococcus radiodurans microarry oxidative stress ionizing radiation.

Analysis of Developmental Proteome at Egg Stage of Drone Honeybees (A. m. ligustica)

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agricultural sciences in China 2010年第3期9卷 392-400页

作者： FANG Yu and LI Jian-ke institute of Apicultural Research, chinese academy of agricultural sciences/Key Laboratory of Pollinating Insect Biology, beijing 100093, P.R.China [a] institute of Apicultural Research Chinese Academy of Agricultural Sciences/Key Laboratory of Pollinating Insect Biology Beijing 100093 P.R.China

An investigation on the proteome of drone egg development of native Italian bee （Apis mellifera ligustica Spinola,1806） was carried out in order to prove up the characteristics in protein expression and regulation at egg stage and open out the molecular mechanism of the development. The experiment was carried out by two-dimensional gel electrophoresis. The results showed that there were 200, 242 and 233 proteins in a wide rang of molecular weight （12.42-169.60 kDa） and in a relatively narrow scope of pI （4.50-9.00） detected on day 1, day 2 and day 3, respectively, during the developmental process of the drone egg. Meanwhile, 164 protein spots were resolved at all the images （i.e., the protein was consistently expressed） along with the egg development, among which 7 were significantly up-expressed （P 〈 0.05） and 4 were significantly down-expressed （P 〈 0.05） while 79 had no significant differences （P 〉 0.05）. In addition, the specific proteins expressing proteins on day 1, day 2 and day 3 were 11, 18 and 18, respectively. Besides, 17 proteins expressed both on day 1 and day 2 but silenced on day 3, and 43 proteins expressed both on day 2 and day 3 but silenced on day 1, while only 8 proteins expressed both on day 1 and day 3 but silenced on day 2. The results indicate that 2-d-old eggs are at the most active expressional stage in the development of drone egg. The protein expressing at all images suggests that it should be indispensable for drone egg development, but their expression pattern is different. The proteins expressing at a specific age of egg suggest that specific proteins are needed in different developmental stages to regulate. And there are more house-keeping proteins in the developmental process of the drone egg than that of worker egg, and it will provide more targets for gene improvement.

关键词： honeybees drone egg two-dimensional gel electrophoresis proteome

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science China Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 2 Graduate University of the chinese academy of sciences, beijing 100049, China 3 College of Resources and Environmental science, Nanjing agricultural University, Nanjing 210095, China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate University of the chinese academy of sciences Beijing 100049 China College of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest China. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

A Brief Review on Application of Information Technique to Agrometeorological Disaster Reduction

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Natural Disaster Reduction in China 1997年第3期 92-96页

作者： Cao Yonghua (Agrpmetorological institute, chinese academy of agricultural sciences, beijing 100081)

Disaster reduction strategy of agrometeorological disasters is a very complicated systematic project. The system is divided into two subsystems: agrometeorological disaster subsystem and dis aster reduction strategy subsystem. The agrometeorological disaster subsystem incIudes the whole process of disaster from occurrence, development to extinction. The subsystem of disaster reduction strategy is strategy measures included prevention, resistance and remedy of disaster The system involves monitoring, forecasting, prevention, resistance, control, loss assessment of disaster and efficiency analysis of disaster reduction. Therefore, modern information techniques (remote sensing, artificial intelligence, crop simulation etc. ) are necessary for improving the a bility of prevention and reduction of

关键词： A Brief Review on Application of Information Technique to Agrometeorological Disaster Reduction Info

Analysis of Genetic Difference Between Species in Lupins by AFLP

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agricultural sciences in China 2002年第8期1卷 856-860页

作者： HAI Lin, XIAO Shi-he, YAN Chang-sheng and ZHANG Xiu-ying(institute of crop Breeding and Cultivation, chinese academy of agricultural sciences, beijing 100081 , P. R . China) institute of crop Breeding and Cultivation Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

The genetic difference between species in 18 lupins (Lupinus L .) varieties including L. angus-tifolius L., L . albus L., L. pilosus Murr. was analyzed using AFLP. A total of 462 bands were observed, a-mong of which, 442 (95.7%) were polymorphic, with an average of 110.5 polymorphic bands for each AFLP primer combination. The average genetic diversity index was 0.781 in this study. The genetic difference between species was higher than that of between varieties, the average identification percentage of four AFLP primer combinations was 100% and 84.7% between species and between varieties, respectively. The cluster analysis indicated that 3 species were distinctly distinguished on the dendrogram using UPGMA method.

关键词： Lupins (Lupinus L.) Genetic difference AFLP

Study on Chromosome Doubling for Haploid Produced by Wheat×Maize Crossing

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agricultural sciences in China 2002年第5期1卷 486-490页

作者： CHEN Xin-min, ZHANG Wen-xiang, GUI Shu-Ian and CHEN Xiao(institute of crop Breeding and Cultivation , chinese academy of agricultural sciences , beijing 100081 , P. R . China) institute of crop Breeding and Cultivation Chinese Academy of Agricultural Sciences Beijing 100081 P. R. China

There is no spontaneous chromosome doubling in haploid plants produced by wheat X maize crossing. In order to obtain doubled haploid, two chromosome doubling methods were used. Results showed that: After adding colchicine solution directly into a medium for young embryos that had been cultured 7 days, frequencies of embryo germination in colchicine concentrations of 50mg/L, 100mg/L and 200mg/L were 32.1% , 26.4% and 16.3% , respectively, and frequencies of chromosome doubling were 85.3% , 100% and 50.0% , respectively. But in the control without colchicine, the frequency of embryo germination was 67.4% and no seed was setting. As the time of colchicine treatment increased from 24 to 72 hours, the frequency of embryo germination was reduced, and 24 hours had better results. After soaking seeding crowns and roots with colchicine solution of 500mg/L, 750mg/L and 1 000mg/L for 5 hours, the frequencies of doubling were 89.6%, 76.0% and 73.3%, respectively. By soaking crowns and roots of strong seedings with 500mg/L colchicine solution, the frequency and efficiency of doubling were 98.2% and 93.2% , respectively.

关键词： Wheat X maize crosses Haploid Doubled haploid