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141.
对性引诱剂监测桔小实蝇雄成虫技术的改进 总被引:12,自引:0,他引:12
研究了添加方式、监测点位置以及监测区域环境对应用性引诱剂甲基丁香酚监测桔小实蝇Bactrocera dorsalisHendel雄成虫动态效果的影响。试验结果表明,采用分期分批、多次添加性引诱剂的方式监测桔小实蝇雄成虫动态,可消除因监测区域内所有诱瓶同一时间添加性引诱剂而造成的浓度突变所引起的成虫出现干扰性高峰,获得更准确的虫情监测结果;监测点的设置位置明显影响监测结果,监测点应包括果园内和果园外;选择较大且环境复杂的区域作为监测点可获得更明确的年发生动态规律。在以上研究基础上,提出了应用性引诱剂监测桔小实蝇雄成虫动态的监测方法。 相似文献
142.
Zhihua Jin Yinlin Lei Jianping Lin Peilin Cen 《World journal of microbiology & biotechnology》2006,22(2):129-134
Summary According to the biosynthetic pathway of pristinamycin, a rational selection procedure with u.v. mutation was performed to obtain a high pristinamycin-producing strain. Aminoacetic acid-resistant mutants (AAr), valine hydroxamate-resistant mutants (VHr), kitasamycin-resistant mutants (KTMr) and 2-deoxy-D-glucose-resistant mutants (DOGr) were selected, successively. A strain Streptomyces pristinaespiralis 12–55 with AAr, Valr, KTMr, and DOGr was obtained, and its production of pristinamycin reached 3000 u/ml which is 100 times higher than that of the parent strain S. pristinaespiralis ATCC 25486. It is inferred that S. pristinaespiralis 12–55 can alleviate catabolite repression caused by carbon sources, provide more acetic acid and valine for pristinamycin biosynthesis and increase its resistance to pristinamycin produced by itself, all of which are favorable for pristinamycin production. The subculture experiments indicated that the hereditary character of high productivity of S. pristinaespiralis 12–55 is stable. The pristinamycin production of S. pristinaespiralis 12–55 in a 15-l fermentor could reach 3010 u/ml after a 56 h batch fermentation. 相似文献
143.
Fuli Liu Xiuliang Wang Jidong Liu Wandong Fu Delin Duan Yingxia Yang 《Journal of phycology》2009,45(5):1228-1233
To establish a molecular‐marker‐assisted system of breeding and genetic study for Laminaria japonica Aresch., amplified fragment length polymorphism (AFLP) was used to construct a genetic linkage map of L. japonica featuring 230 progeny of F2 cross population. Eighteen primer combinations produced 370 polymorphic loci and 215 polymorphic loci segregated in a 3:1 Mendelian segregation ratio (P ≤ 0.05). Of the 215 segregated loci, 142 were ordered into 27 linkage groups. The length of the linkage groups ranged from 6.7 to 90.3 centimorgans (cM) with an average length of 49.6 cM, and the total length was 1,085.8 cM, which covered 68.4% of the estimated 1,586.9 cM genome. The number of mapped markers on each linkage group ranged from 2 to 12, averaging 5.3 markers per group. The average density of the markers was 1 per 9.4 cM. Based on the marker density and the resolution of the map, the constructed linkage map can satisfy the need for quantitative trait locus (QTL) location and molecular‐marker‐assisted breeding for Laminaria. 相似文献
144.
Koshi Kitamura Jin Yoshimura Kei-ichi Tainaka Satoshi Yokojima 《Ecological Research》2009,24(3):533-546
River management often conflicts with the conservation of species in river ecosystems. In Japan, almost all river systems
have been covered by concrete walls. Such river improvement works caused critical damage to river ecosystems. Here we report
the ongoing extinction process of a rare aquatic plant by several consecutive heavy rains. The aquatic plant, Schoenoplectus gemmifer C. Sato, T. Maeda & Uchino, is an extremely rare endemic species that is strictly associated with springwater. The species
is only found in 23 locations in Japan, including only two major habitats: Hamamatsu and Oita. We monitored the population
fluctuations of S. gemmifer at three river systems in Hamamatsu. In the largest habitat, Higashikanda River, the population size of the species decreased
to nearly 1/10th in 2004, due to several severe floods. Spatial and temporal records exhibit four stages of damaging process.
The stepwise damages were found to be caused by a rapid flow of water accelerated by the river improvement work (made in 1985).
The reproduction and growth by seeds and gemmae did not evidently cover the losses by flood washed out. In the other two rivers,
one was extinct and the other is now at the risk of extinction. The modified river structures may be responsible for the near-extinction
of S. gemmifer in Hamamatsu area. We propose two policies for the conservation of this species: (1) the artificial cultivation of gemmae
and seedlings and (2) the modification of river structure to decrease the number of washed-out plants. In particular, it is
important to decrease the water velocity at floods by some methods. 相似文献
145.
神经细胞尼氏体染色方法改良 总被引:2,自引:0,他引:2
组织细胞的染色无论在病理学诊断还是在科学研究与教学工作中,都具有重要的意义和使用价值。为了更好的研究神经组织,方便医学诊断、科研和教学工作,对3种常见尼氏体染色方法包括硫堇、甲苯胺蓝、吉姆萨染色法做了一些改良。改进的尼氏体染色法能够使脑组织切片更清晰美观,更有利于科研工作者对神经组织及尼氏体的研究。 相似文献
146.
Beltrametti F Rossi R Selva E Marinelli F 《Journal of industrial microbiology & biotechnology》2006,33(4):283-288
During a strain improvement program, spontaneous mutants with single or combined resistance to streptomycin (Strr), gentamycin (Genr) or rifamycin (Rifr) were selected from the industrial strain of Planobispora rosea, which is the producer of thiazolylpeptide GE2270. Among the mutants resistant to each single antibiotic, higher producers
occurred more frequently (60%) among Genr than in Rifr (10%) and Strr (24%) populations. Two Genr mutants showed up to 1.5-fold improvement in GE2270 production while single resistant mutants Strr and Rifr produced slightly more than the parental strains. The combination of Strr and Rifr in the same strain improved GE2270 yield up to 1.7-fold. Finally, a higher GE2270 producing strain (1.8-fold improvement
with respect to the parental strain) was selected among those mutants with triple resistance to streptomycin, rifamycin and
gentamycin. A hierarchical increase in aerial mycelium and spore formation was observed which paralleled GE2270 production
improvement. 相似文献
147.
Demain AL 《Journal of industrial microbiology & biotechnology》2006,33(7):486-495
In order for a natural product to become a commercial reality, laboratory improvement of its production process is a necessity since titers produced by wild strains could never compete with the power of synthetic chemistry. Strain improvement by mutagenesis has been a major success. It has mainly been carried out by “brute force” screening or selection, but modern genetic technologies have entered the scene in recent years. For every new strain developed genetically, there is further opportunity to raise titers by medium modifications. Of major interest has been the nutritional control by induction, as well as inhibition and repression by sources of carbon, nitrogen, phosphate and end products. Both strain improvement and nutritional modification contribute to the new process, which is then scaled up by biochemical engineers into pilot scale and later into factory size fermentors. 相似文献
148.
Kazuhiko?Yokota Yasunari?MatsunoEmail author Masaru?Yamashita Yoshihiro?Adachi 《The International Journal of Life Cycle Assessment》2003,8(3):129-136
Scope In this study, a dynamic model was built in which LCA and PBM were integrated to quantitatively assess the total environmental
impacts induced by the product population in a society over time. Specifically, a determination was carried out concerning
how Japan’s air conditioner population is used (lifetime distribution, number of units, etc.) and an assessment was made concerning
the Global Warming Potential (GWP) associated with the air conditioner population.
Methods The proposed dynamic model was applied to air conditioners for analyzing the total GWP caused by the air conditioner population
in Japan from 1990 to 2010. To create a trend forecast model for future environmental load, scenarios for air conditioner
production up to 2010 were formulated and the total GWP from the air conditioner population was predicted. Conducted also
were sensitivity analyses whose parameters were air conditioner performance, lifetime and the rate of refrigerant recovery
when retired units are processed.
Results and Discussion Applying the PBM to the air conditioner population in 2000, it was found that 81.5 million units consumed 5.94 x 10p10 kWh in that year, which was a 6.1 % increase in the total annual power consumption in 1990. In both a stationary scenario
and a steady growth (1.5% annual increase), it was found that the total GWP would be 27.7% higher than in 1990 under the stationary
scenario and 37.8% higher under the steady growth scenario. The improvements in air conditioner performance will have a small
effect on reducing the total GWP from that population. Furthermore, in connection with the average lifetime, it was found
that the GWP, due to refrigerant releases when units are disposed of, would be relatively large in 2000 and the following
years.
Conclusions Thus, shorter product lifetimes will spur a replacement of air conditioners with new units, a situation that will only lead
to the reduction of GWP if the recovery rate of refrigerant is to be achieved to more than 50% under the stationary scenario.
Recommendations and Outlook To meet COP3 targets for Japan in 2010 (i.e. to reach the same level as in 1990 for household appliances), our study shows
that it will be vital to raise the refrigerant recovery rate. If the number of air conditioners in use remains unchanged,
recovery would have to be 45.7%, but under the steady growth scenario it would have to be at least 60.4%. Therefore, it will
be difficult to meet COP3 targets unless the refrigerant recovery rate is strongly increased. This method is applicable to
assess not only the GWP of air conditioners, but also other environmental impacts caused by a variety of product populations,
which will be quite effective for setting targets of products’ performance, policymaking, etc. 相似文献
149.
I. Petsas K. Psarianos A. Bekatorou A.A. Koutinas I.M. Banat R. Marchant 《Biotechnology letters》2002,24(7):557-560
A commercial culture of Kefir grew well at 30°C and 37°C with NaCl up to 4% (w/v) but at 42°C and 4% (w/v) NaCl it grew very slowly. These conditions were selected for the mutation with N-methyl-N-nitrosoguanidine in order to improve cell yield at high temperatures and salt concentration. The mutated cells had higher biomass and growth rate compared with the original culture. The improvement of Kefir at high temperatures and salt concentrations offers advantages for uses in single cell protein production and alcohol production from whey containing high salt. 相似文献
150.
Greengram or mungbean (Vigna radiata (L.) Wilczek), which originated in the Indian sub-continent, is an important pulse crop in India. Genetic diversity and patterns of variation among 111 accessions representing the better agronomic types from the entire collection of the National Bureau of Plant Genetic Resources were studied. Wide variation in morphological and agronomic traits viz. number of pods per plant, yield per plant, 100-seed weight, fruit setting capacity, flowering period, maturity, number of pod bearing peduncles, plant height, number of primary branches, length of branch, nodulation and leafiness was observed. Grain yield was found to be significantly correlated with 100-seed weight and pod length. The data were subjected to cluster and principal components analysis. The accessions were grouped into six discrete and well-defined clusters. The study demonstrated the patterns of variation at the population level. The multivariate analysis was useful in identifying a group of accessions with yield enhancing traits within a highly diverse group of accessions and their potential value in greengram improvement is suggested. 相似文献