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1.
Ashalatha?S.?Nair Chee?How?Teo Trude?Schwarzacher Pat?Heslop?HarrisonEmail author 《Euphytica》2005,143(3):285-290
Summary The banana cultivars are originated from the intra- and inter-specific hybridization of two wild diploid species, Musa acuminata Colla and Musa balbisiana Colla, contributing the A and B genomes, respectively. They are classified into genomic groups by scoring morphological features.
Molecular markers provide a quick and reliable system of genome characterization and manipulation in breeding lines. In the
present study a PCR based molecular marker specific for B genomes is been reported. The IRAP primer, designed based on the
LTR sequence of banana Ty3-gypsy-like retroelement (Musa acuminata Monkey retrotransposon, AF 143332), was used to identify the B genome in the banana cultivars. Further a primer pair designed
from B specific bands of Musa balbisiana `Pisang Gala' was used to classify AAB and ABB cultivars in the collection. Among the 36 cultivars tested with this primer,
the B specific band was absent in the AA and AAA cultivars (except in one AAA and AAB cultivar) but present in all other AB,
AAB and ABB cultivars. Among the triploid AAB/ABB, the PCR products with B specific primers showed restriction pattern polymorphism
with AluI. In ABB genomes the band intensity was high whereas low intensity band observed in AAB genomes. Four cultivars reported
to have the ABB genome showed a pattern similar to AAB, and one cultivar reported to have AAA genome showed a pattern similar
to ABB genome, suggesting missampling or misidentification. The primers used in this study are useful to identify the presence
of B genome in banana cultivars, and band intensity may be a preliminary indicator of ploidy level of the B genome but needs
further studies with competitive PCR for clarification.
These authors contributed equally in this paper. 相似文献
2.
The herbicide, hexazinone, was applied four ways over ponderosa pine, 2–0 seedlings planted in northeast Oregon. The four treatments were two broadcast applications, a single broadcast application, a large spot application, and a small spot application. Seedling survival and growth were monitored for five growing seasons. Results indicate that survival more than doubled with either large or small spot applications compared to no application, and either one or two broadcast applications can increase survival an additional 30% over spot applications. Differences in stem volume were substantial, with two broadcast applications yielding more than twice the volume of a single broadcast treatment and more than five times the volume of seedlings treated with spot applications. Trees in small spots were still three times bigger than surviving seedlings in the control. These results are consistent with the concept of competition threshold. Management implications were considered in terms of cost of established seedlings. Although broadcast applications cost more per acre than spot applications, gains in seedling survival, growth and quality offset the additional cost and translate into lower established seedling costs. The cost effectiveness of broadcast applications also may be seen in the elimination of replanting or in-planting requirements and increases in long-term growth potential of the established trees. 相似文献
3.
Tredoux A de Villiers A Májek P Lynen F Crouch A Sandra P 《Journal of agricultural and food chemistry》2008,56(12):4286-4296
A simple method for the analysis of major wine volatiles and semivolatiles by stir bar sorptive extraction in combination with thermal desorption and gas chromatography-mass spectrometry (SBSE-TD-GC-MS) was developed. Significant experimental parameters such as extraction time, temperature, salt addition, pH, and thermal desorption parameters were optimized to provide a sensitive and robust analytical method. The method provided good repeatability (%RSD < 10%) for 38 major wine volatile compounds, including alcohols, acids, esters, phenols, aldehydes, ketones, and lactones. Quantitative data for 62 South African red and white wines were used to study the suitability of major volatile data for the differentiation of wine samples according to grape variety or cultivar. Principal component analysis (PCA) and cluster analysis (CA) showed that most of the variation in volatile composition between wine samples could be ascribed to differences in wine age, wood contact, and fermentation practices. Despite the contribution of these factors, discriminant analysis (DA) was successfully applied to the classification of red and white wine samples according to cultivar. 相似文献
4.
Wrieden WL Anderson AS Longbottom PJ Valentine K Stead M Caraher M Lang T Gray B Dowler E 《Public health nutrition》2007,10(2):203-211
OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design. 相似文献
5.
Liam Hanrahan Pat Tuohy Noirin McHugh James O'Loughlin Brian Moran Pat Dillon James Breen Michael Wallace Laurence Shalloo 《Grass and Forage Science》2019,74(3):548-558
The physical and financial performance data used for analysis were obtained over a 6‐year period (2010–2015), from two different databases including a nationally representative data set of dairy farmers and a detailed data set of seven individual farms. Initial analysis indicated significant variations across soil type and region, across a wide range of physical and financial parameters. Further detailed analysis was completed using a group of seven farms participating in a Heavy Soils Programme (HSP), which were compared to different cohorts of the nationally representative database (National Farm Survey [NFS]), ranked on net profit per ha. The HSP farms utilized larger quantities of grass DM per ha per year than the median of the NFS farms, at similar grazing season lengths, but were using lower levels of purchased feed. Economic analysis indicated the HSP farmers achieved significantly lower net profits per hectare to the NFS median group but significantly higher net profits per kg of fat and protein. The HSP farms also achieved significantly greater overall net farm income per year (€83,788), when compared to the median nationally (€67,898), over the 6‐year period (excluding owned land and labour). The mean return on assets ascertained by the HSP farmers was also significantly greater, at 5.75% per year compared to 3.49% achieved by the median of NFS farms. In conclusion, this study has indicated that efficient dairy businesses operating on poorly drained soils can be as profitable as those across all ranges of soil types. 相似文献
6.
Davina Van Goethem Sebastiaan De Smedt Roland Valcke Denis O'Connor Pat O'Connell Sonja Denollin Roeland Samson Geert Potters 《世界竹藤通讯》2012,10(5):46
在寻找可再生能源和生物基材料方面,竹子已经被作为一种高产的生物质产品,可以用来作为土壤污染的修复性植物。由于这个原因,一个产量指示的增长模型需要一个健康的指标参数来检测植物的性能。因此,本研究对位于爱尔兰都伯林的Ballyboughalo公司的毛竹蒿草(Phyllostachys humilis)叶子的叶绿素荧光进行了测量。本研究测量结果涵盖了这种竹类每个节点的叶子,并且建立在了随季节性变化的基础上。最常使用的叶绿素荧光参数是Fv/Fm值,又称TRO/ABS (即被困的光子与吸收的光子数之比)。随季节的推移以及这个参数较大的变化,本研究将春天与一年中其它的季节进行对比观察测量。在过去的一年,这种植物的上部叶片比下部叶片表现更好。本研究的发现被整合在一个数学模型中,其目的是为预测和解释在其它立地条件下的植物的性能。 相似文献
7.
8.
副猪嗜血杆菌的分离培养和血清型鉴定 总被引:70,自引:0,他引:70
从全国十多个省市送检的疑似患多发浆膜炎与关节炎猪的病料中分离到32株细菌,进行了细菌形态观察、培养特性和生化特性鉴定;根据副猪嗜血杆菌16S rRNA序列设计引物进行PCR扩增,将822bp扩增片段连入T-载体后测序,再与GenBank(M75065)中的序列进行比对,表明其与国外副猪嗜血杆菌菌株16S rRNA序列的同源性为97%以上,确定为副猪嗜血杆菌(Haemophilus parasuis,Hps)。将其中的15株按Kieletein-Rapp-Gabriedson(KRG)琼脂扩散血清分型方法进行血清型鉴定,结果为血清5型3株、血清4型4株、血清13型2株、血清12型2株,另外有4株不能进行分型。该结果表明副猪嗜血杆菌在我国广泛存在。 相似文献
9.
Survival ofEscherichia coli was studied in water from the Great Salt Lake, a highly saline lake with an ionic composition much like sea water. Samples used were from the most concentrated north arm (343.1 g l?1 solids) and the less concentrated south arm (about 113 g l?1 solids). At temperatures from 20°C to 9°C the bacterial death rate (k) for the north arm was ?0.17 log day?1 and the south arm and 1:3 dilution ?0.28 log day?1. Above 9°C the rate of death increased approximately exponentially and at 19°C the rate of death increased approximately exponentially and at 19°C the death rate was ?1.31 log day?1 in the north arm and ?0.98 log day?1 in the lower salinity water. These rates fall within those reported for sea water and are much higher than fresh water. Possible causes of death are discussed with the most likely being the high concentrations of minor elements or osmotic stress. The survival characteristics ofE. coli in waters with a sea water-like composition should require the same health concern as sea water regardless of the actual concentration of salt. High salt water of other ionic composition may behave differently, however. 相似文献
10.
Over four hundred vegetation samples were collected for total Hg determination as part of a biogeochemical survey in the Precambrian
Shield region near Huntsville, Ontario. An objective of the survey was to obtain accurate data describing the spatial and
temporal variation of Hg concentrations in vegetation. Five tree species, clubmosses, mosses, lichen and fungi were collected
along three transects each 8 to 10 km long. The samples were digested using a hot H2SO4/HNO3 mixture followed by cold-vapor AAS detection. Very low detection limits (less than 1.0 ng g−1) were achieved by performing the analyses in a clean, Hg-free laboratory. The Hg concentration of coniferous needles did
not vary significantly over eight weeks of the summer, but did vary significantly between first and second year growth. In
all tree species examined, Hg concentrations in needles/leaves were two to three times as high (by dry weight) as that in
twig tissue from the same branch. Differences in Hg content between tissues of different types and ages constituted a major
source of within-site variation between plants of the same species. 相似文献