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101.
Xiaoling Li Xiaoming Yu Ningning Wang Qizhi Feng Zhenying Dong Lixia Liu Jinglin Shen Bao Liu 《Plant Cell, Tissue and Organ Culture》2007,90(2):153-168
A simple tissue culture protocol was developed for efficient plant regeneration from young inflorescence-derived calli in
wild barley, Hordeum brevisubulatum (Trin.) Link, an important pasturage grass. Genetic and epigenetic instabilities in the regenerated plants (regenerants)
were assessed by three molecular markers AFLP, S-SAP and MSAP. Two pools of calli derived from young inflorescences of a single
donor plant and 44 randomly chosen regenerants were subjected to AFLP analysis. Results showed that 74 out of 793 scored bands
were polymorphic among the studied samples, giving rise to a genetic variation frequency of 9.3%. The number of variant bands
as compared to the donor plant varied greatly among the regenerants, with a small number of regenerants accumulated a large
number of variant bands (maximum 55), while the majority of regenerants showed only 2–3 variant bands. A subset of regenerants
together with the two pools of calli were selected for S-SAP and MSAP analysis to detect possible retrotranspositional activity
of a prominent retroelement family, BARE-1, in the genomes of Hordem species, and possible alterations in cytosine methylation. S-SAP analysis showed that of the 768 scored bands, 151 were polymorphic
among the analyzed samples, giving rise to a genetic variation frequency of 19.7%, albeit no evidence for retrotranspositional
event was obtained based on locus-specific PCR amplifications. MSAP analysis revealed that tissue culture has caused cytosine
methylation alterations in both level and pattern compared with the donor plant. Sequencing of selected variant bands indicated
that both protein-coding genes and transposon/retrotransposons were underlying the genetic and epigenetic variations. Correlation
analysis of the genetic and epigenetic instabilities indicated that there existed a significant correlation between MSAP and
S-SAP (r = 0.8118, 1,000 permutations, P < 0.05), whereas the correlation between MSAP and AFLP (r = 0.1048) is not statistically significant.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Xiaoling Li and Xiaoming Yu contributed equally to this work. 相似文献
102.
103.
鄂尔多斯高原蒙古族食用野生植物传统知识的研究 总被引:2,自引:0,他引:2
运用民族植物学"5W+1H"提问法,结合访谈方法和野外调查进行编目,研究了鄂尔多斯高原蒙古族食用野生植物的传统知识。结果:1)鄂尔多斯蒙古族传统食用植物22科32属50种,其中野生粮用植物14种、野生蔬菜13种、野果植物18种、野果酒植物3种、野生调味植物5种、野生薰净植物2种、催化乳制品植物1种。2)鄂尔多斯蒙古族野生食用植物传统知识包括7个方面,其中用植物薰净和消毒奶食器具的传统知识、用冷蒿催化加速油脂成分从奶子中分离的传统知识是蒙古族植物饮食文化的创新。具有鲜明的民族特色、简单、快捷的"果实+奶食"酿果酒文化,能够说明蒙古族祖先在生产实践中掌握了开发和利用植物资源的更高水平的技术和文化。食用芨芨草颖果、选用中间锦鸡儿韧皮部和白沙蒿的果实做面食粘合剂的传统知识是区域特色的文化。3)因生态环境条件的不同,山区、沙区、盐渍区和丘陵区蒙古族牧民的传统食用植物知识表现出多样性,反映了生态环境条件的多样性。4)鄂尔多斯蒙古族野生食用植物传统知识丰富了蒙古族饮食文化,对蒙古族文化的发展做出了贡献。开展搜集、研究、保护和科学分析鄂尔多斯蒙古族植物传统知识的工作,将对社会经济的可持续发展产生十分积极的直接影响。 相似文献
104.
西双版纳傣族利用野生蔬菜种类变化及原因分析 总被引:1,自引:0,他引:1
运用民族植物学的方法,选择西双版纳自然及社会经济发展不同的三个傣族村寨曼安、曼伞和曼广囡为研究对象,调查当地村民利用野生蔬菜情况,并探讨利用种类变化的原因。三个傣族村寨村民利用的野生蔬菜有228种,分属于75个科,其中曼安村寨147种,曼伞村寨144种,曼广囡村寨105种。通过Multivariate方差分析(P<0.05)表明:不同村寨的村民平均每人提及的野生蔬菜物种数存在显著差异;年轻组平均每人提及的野生蔬菜物种数明显低于年长组,不同性别之间差异不显著;野生蔬菜知识的流失在男性之间比女性更为严重。最后对影响野生蔬菜利用的因素,野生蔬菜利用变化的原因以及传统野生蔬菜知识的流失进行了分析,就如何保护传统知识进行了探讨。 相似文献
105.
Polish Arabian horses are one of the oldest and the most important Arab populations in the world. The Polish Arabian Stud Book and the Genealogical Charts by Skorkowski are the main sources of information on the ancestors of Polish Arabs. Both publications were viewed as credible sources of information until the 1990s when the data regarding one of the dam lines was questioned. The aim of the current study was to check the accuracy of the pedigree data of Polish dam lines using mtDNA analysis. The analyses of a 458 bp mtDNA D-loop fragment from representatives of 15 Polish Arabian dam lines revealed 14 distinct haplotypes. The results were inconsistent with pedigree data in the case of two lines. A detailed analysis of the historical sources was performed to explain these discrepancies. Our study revealed that representatives of different lines shared the same haplotypes. We also noted a genetic identity between some lines founded by Polish mares of unknown origin and lines established by desert-bred mares. 相似文献
106.
C. Douglas Boyette Robert E. Hoagland Hamed K. Abbas 《Biocontrol Science and Technology》2007,17(2):171-178
An isolate of the fungus Myrothecium verrucaria was evaluated for its biocontrol potential against common purslane, horse purslane, spotted spurge, and prostrate spurge, all serious weed pests in commercial tomato fields in the southeastern US. In greenhouse and field tests, M. verrucaria was highly virulent against these weeds when applied as conidial sprays formulated in 0.2% Silwet L-77 surfactant, even in the absence of dew. In field test plots naturally infested with these weeds, seedlings in the two-to-three leaf growth stage treated with M. verrucaria at 2×107 conidia mL-1 in 0.2% Silwet, exhibited leaf and stem necrosis within 24 h following inoculation, with mortality occurring within 96 h. After 7 days, M. verrucaria had killed 90-95% of both purslane species and 85-95% of both spurge species. Tomatoes that were transplanted into plots treated with M. verrucaria remained healthy and vigorous throughout the growing season. Since M. verrucaria effectively controlled several common weeds under field conditions, this fungus appears to have potential as an effective bioherbicide for pre-plant weed control in production systems with transplanted tomato. 相似文献
107.
M. Mizianty L. Frey W. Bieniek P. Boroń M. Szklarczyk 《Plant Systematics and Evolution》2007,269(1-2):15-28
Seven populations of Hordelymus europaeus and four populations of Leymus arenarius from Poland were subjected to examination of 36 morphological characters. This study showed that both species are relatively
uniform and that morphological variation of their populations represents a continuum. Of those, three populations of either
species were selected for analysis with molecular markers – RAPDs and AFLPs. These populations differed with respect of geographical
location as well as syntaxa and habitat. RAPD-PCR was performed for individual plants and clearly grouped them according to
the population origin. For either H. europaeus or L. arenarius - the studied populations differed in degree of their intrinsic variation while none of them as a whole was significantly
different from the remaining ones. In AFLP analysis the studied populations were represented by DNA pools of several individual
plants. Also this approach allowed discrimination among the population samples of both H. europaeus and L. arenarius. Both RAPDs and AFLPs were accordant in indication that H. europaeus exceeds L. arenarius with respect to variation accumulated at the DNA level.
It is the sixth paper of the series: Biodiversity of wild Triticeae (Poaceae) in Poland. The first is: M. Mizianty (2005).
Variability and structure of natural populations of Elymus caninus (L.) L. based on morphology. Pl. Syst. Evol. 251: 199-216.
The second: M. Mizianty, and M. Szklarczyk (2005). Systematic significance of Elymus caninus morphological characters revealed
by AFLP analysis. In: L. Frey (ed.) Biology of grasses. W. Szafer Institute of Botany, Polish Academy of Sciences. Kraków,
pp 9–21. The third: M. Mizianty et al. (2006). Variability and structure of natural populations of Elymus caninus (L.) L.
and their possible relationship with Hordelymus europaeus (L.) Jess. ex Harz revealed by AFLP analysis. Pl. Syst. Evol. 256:
193–200. The fourth: M. Mizianty (2006). Variability and structure of natural populations of Hordeum murinum L. based on morphology.
Pl. Syst. Evol. 261: 139–150. The fifth: B. Paszko Variability and structure of natural populations of Brachypodium pinnatum
and B. sylvaticum based on morphology. Acta Soc. Bot. Pol. (in press). 相似文献
108.
Female Tabanus nigrovittatus were field collected and used in laboratory experimentation to explore physiological and behavioral factors that affect engorgement. Previous studies showed sulfakinins act as feeding satiety factors in insects. This study demonstrates that sulfakinins have differing effects on engorgement that is dependent on the feeding technique used in the laboratory. The satiety effect of sulfakinin on flies engorging using the blood-soaked Kimwipe® feeding technique is not in agreement with previous experiments using an alternate feeding technique with artificial membranes. This study is the first to demonstrate that the temperature of blood is a significant factor for engorgement in this species. Also, the percentage of flies engorging is significantly different depending on the feeding technique used. 相似文献
109.
Plant communities around natural CO2 springs have been exposed to elevated CO2 levels over many generations and give us a unique opportunity to investigate the effects of long-term elevated CO2 levels on wild plants. We searched for natural CO2 springs in cool temperate climate regions in Japan and found three springs that were suitable for studying long-term responses
of plants to elevated levels of CO2: Ryuzin-numa, Yuno-kawa and Nyuu. At these CO2 springs, the surrounding air was at high CO2 concentration with no toxic gas emissions throughout the growth season, and there was natural vegetation around the springs.
At each site, high-CO2 (HC) and low-CO2 (LC) plots were established, and three dominant species at the shrub layers were used for physiological analyses. Although
the microenvironments were different among the springs, dicotyledonous species growing at the HC plots tended to have more
starch and less nitrogen per unit dry mass in the leaves than those growing at the LC plots. In contrast, monocotyledonous
species growing in the HC and LC plots had similar starch and nitrogen concentrations. Photosynthetic rates at the mean growth
CO2 concentration were higher in HC plants than LC plants, but photosynthetic rates at a common CO2 concentration were lower in HC plants. Efficiency of water and nitrogen use of leaves at growth CO2 concentration was greatly increased in HC plants. These results suggest that natural plants growing in elevated CO2 levels under cool temperate climate conditions have down-regulated their photosynthetic capacity but that they increased
photosynthetic rates and resource use efficiencies due to the direct effect of elevated CO2 concentration. 相似文献
110.
A scabies outbreak, with unusually high mortality and morbidity, occurred in a poorly managed goat flock in north-eastern Italy. The source of infection was traced back to contact with scabietic chamois (Rupicapra rupicapra) within a recognised sylvatic focus of the disease. Spill-over of scabies from chamois to goats is a matter of great concern to resource managers. Currently scabies-free populations of wild Caprinae in the central and western Alps may eventually be exposed to infected goats transported over long distances. Sanitation of the studied flock was obtained following three applications of pour-on moxidectin at an approximate dose of 500 mcg/kg. Follow-up included titration of circulating anti-Sarcoptes antibodies in a labelled avidin–biotin ELISA test. Two operators developed pseudoscabies after handling the infested flock. 相似文献