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The use of <Emphasis Type="Italic">Vp1</Emphasis> in real time RT-PCR to select for pre-harvest sprouting tolerance in triticale 总被引:1,自引:0,他引:1
In spite of the availability of laboratory and field tests there is still a major problem to select pre-harvest sprouting
(PHS) tolerant triticale varieties in a reliable, field-independent way. One approach to minimize the influence of environmental
conditions and physio-morphological traits on PHS detection is using molecular genetic tools. The ‘viviparous’ Vp1 gene has been repeatedly described to play an important role in dormancy in wheat. A quantitative RT-PCR assay based on the
expression of the Vp1 gene has been developed. Specific primers were designed for detecting Vp1 in both wheat and triticale. The expression levels of Vp1 were normalized using reference genes and relatively quantified with the comparative Ct-method. However, the first results indicate that the achieved Vp1 expression levels at 50 days post anthesis are not useful to select for PHS tolerance, both in wheat and triticale. This
negative outcome so far is possibly due to the existence of several splicing events or to the late assaying moment in the
kernel development, when Vp1 expression is found to be low. 相似文献
24.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.25.
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Total body water (TBW) in 17 suckling and six lactating llamas was estimated from isotope dilution at three different post natum and lactation stages using both 18O and deuterium oxide (D2O). In total, 69 TBW measurements were undertaken. While TBW in lactating dams, expressed in kilogram, remained stable during
the three measurement periods (91.8 ± 15.0 kg), the body water fraction (TBW expressed in percent of body mass) increased
slightly (P = 0.042) from 62.9% to 65.8%. In contrast, TBW (kilogram) in suckling llamas increased significantly (P < 0.001) with age and decreased slightly when expressed as a percentage of body mass (P = 0.016). Relating TBW to body mass across all animals yielded a highly significant regression equation (TBW in kilogram = 2.633 + 0.623
body mass in kilogram, P < 0.001, n = 69) explaining 99.5% of the variation. The water fraction instead decreased in a curve linear fashion with increasing body
mass (TBW in percent of body mass = 88.23 body mass in kilogram−0.064, P < 0.001, R
2 = 0.460). The present results on TBW can serve as reference values for suckling and lactating llamas, e.g., for the evaluation
of fluid losses during disease. Additionally, the established regression equations can be used to predict TBW from body mass,
providing that the body masses fall inside the range of masses used to derive the equations. 相似文献
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Extract Since the announcement of my appointment to the position of Dean, Faculty of Veterinary Science, Massey University, I have been asked frequently what contributed most strongly to my decision to withdraw from the mainstream of corporate functioning in the U.S.A.; I readily admit it was a decision that was neither easily, nor lightly, determined. 相似文献
28.
Hossein Hosseini Moghaddam Leen Leus Jan De Riek Johan Van Huylenbroeck Erik Van Bockstaele 《Euphytica》2012,184(3):413-427
Disease resistance is a sought-after trait in plant breeding programmes. One strategy to make resistance more durable is to
increase the number of resistance genes, thereby increasing the number of pathotypes withstood. One of the most important
diseases on roses is powdery mildew (PM) (Podosphaera pannosa). Recent studies show that pathotypes of PM and different types of resistances in roses exist. The results of this study
aim to contribute to PM resistance in roses by the development of pathotype-specific markers on a genetic map. A diploid rose
population (90 genotypes) derived from a cross between Rosa wichurana and Rosa ‘Yesterday’ was used to construct a genetic linkage map encompassing 20 AFLP primer combinations, 43 SSR, and 2 morphological
markers. By applying the F1 pseudo test cross population strategy, two parental linkage maps were constructed (parent ‘Yesterday’
536 cM; parent R. wichurana 526 cM). Both parental maps consisted of seven linkage groups with an average length of 70 cM (Kosambi) corresponding to
the seven haploid rose chromosomes. These new maps were used to identify QTLs controlling disease resistance. The offspring
population was screened for resistance to two PM pathotypes, R–E and R–P. QTLs for controlling pathotype-specific disease
resistance were mapped by applying Kruskal–Wallis rank-sum tests and simple interval mapping. With two pathotypes analysed,
nine QTL loci were detected on linkage groups 2, 3, 5 and 6, explaining 15–73% of the phenotypic variance for pathotype-specific
disease response. The genetic maps developed here will be useful for future rose breeding, pathotype-specific resistance research
and development of a consensus map for roses. 相似文献
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