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1.
D. Li I. Barclay K. Jose K. Stefanova R. Appels 《Molecular breeding : new strategies in plant improvement》2008,22(2):217-225
A new mutation at the acetohydroxyacid synthase (AHAS) locus on chromosome 6D of wheat was analyzed in detail because it conferred
an improved resistance to the imidazolinone group of herbicides. Sequence analysis showed that the mutation was at the Ala122
position (A122T), a position in AHAS which has not to date been identified in imidazolinone resistant wheat lines even though
the position has been identified in other plants and is associated with resistance. An allele-specific assay for the mutation
(in the wheat line Brookton-8) was developed and used in a genetic analysis. Two mapping populations were analysed and the
doubled haploid progeny from the cross Brookton-8 × Clearfield STL proved to be most informative. The AHASAla122 mutation (A122T) was allelic to the AHASSer653 mutation (S653N) in Clearfield STL (Imi1, on chromosome 6D) and hence was assigned to the chromosome 6D locus. The analysis
of the doubled haploid lines in the mapping population demonstrated the greater resistance conferred by the A122T mutation
because lines from the same cross and carrying either the A122T or S653N mutations could be directly compared.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Harbor seal ( Phoca vitulina ) haul-out site use may be affected by natural or anthropogenic factors. Here, we use an 11-yr (1997–2007) study of a seal colony located near a mariculture operation in Drakes Estero, California, to test for natural (El Niño-Southern Oscillation (ENSO), density-dependence, long-term trends) and anthropogenic (disturbance or displacement related to oyster production activities) factors that may influence the use of haul-out subsites. Annual mariculture related seal disturbance rates increased significantly with increases in oyster harvest ( r s = 0.55). Using generalized linear models (GLMs) ranked by best fit and Akaike's Information Criteria, ENSO and oyster production (as a proxy for disturbance/displacement) best explained the patterns of seal use at all three subsites near the mariculture operations, with effects being stronger at the two subsites closest to operations. Conversely, density-dependence and linear trend effects poorly explained the counts at these subsites. We conclude that a combination of ENSO and mariculture activities best explain the patterns of seal haul-out use during the breeding/pupping season at the seal haul-out sites closest to oyster activities. 相似文献
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Accounting for weather and time-of-day parameters when analysing count data from monitoring programs
Yves Bas Vincent Devictor Jean-Pierre Moussus Frédéric Jiguet 《Biodiversity and Conservation》2008,17(14):3403-3416
Problems induced by heterogeneity in species and individuals detectability are now well recognized when analysing count data.
Yet, most recent techniques developed to handle this problem are still hardly applicable to many monitoring schemes, and do
not provide abundance estimates at the point count scale. Here, we show how using simple weather variables can be a useful
surrogate to detect variability in species detectability. We further look for a potential bias or loss in statistical power
based on count data while ignoring weather and time-of-day variables. We first used the French Breeding Bird Survey to test
how each of the counts of the 97 most common breeding species was influenced by weather and time-of-day variables. We assessed
how the estimation of each species response to fragmentation could be influenced by correcting counts with such variables.
Among 97 species, 75 were affected by at least one of the five weather and time-of-day variables considered. Despite these
strong influences, the relationship between species abundance and fragmentation was not biased when not controlling counts
for weather and time-of-day variables and further found no improvement in statistical power when accounting for these variables.
Our results show that simple variables can be very powerful to assess how species detectability is influenced by weather conditions
but they are inconsistent with any specific bias due to heterogeneous detectability. We suggest that raw count data can be
used without any correction in case the sources of variation in detectability could be considered independent to the factor
of interest. 相似文献
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There was little release of extractable SO4-S during four weeks from CS2 applied by injecting into two S-deficient soils. In this incubation experiment, the rate of CS2 was 30 μg S g−, placement was injection at 9 cm depth, soil temperature was 20°C, and soil moisture tension was 33 kPa. The yield of barley
forage after seven weeks in the greenhouse showed only small increases from 10 or 30 μg S g−1 of CS2 as compared to Na2SO4, on the two soils.
While CS2 supplied little plant available S in the short term, it was an effective inhibitor of nitrification. In the laboratory, or
in the field, the injection of CS2 (with N fertilizers) at a point 9 cm into the soils either stopped or reduced nitrification. In one laboratory experiment,
35 μg of CS2 g−1 of soil with urea reduced nitrification for at least four weeks; and in another experiment 20 μg of CS2 g−1 of soil with aqua NH3 nearly or completely inhibited nitrification at 20 days. In two field experiments, 3 and 12 μg of CS2 g−1 of soil (or 6 and 24 kg ha−1) with aqua NH3 inhibited nitrification from October to the subsequent May. In addition, CS2 reduced the amount of ammonium produced from the soil N, both in these two field experiments and in the laboratory experiments.
That is to say, CS2 injected at a point, inhibited both nitrification and ammonification.
In other field experiments, CS2 at a rate of 10 kg ha−1 was injected in bands 9 cm deep with urea in October, and by May there was still reduced nitrification. Less than half of
the fall-applied urea alone was recovered as mineral N, but with the application of CS2 the recovery was increased to three-quarters.
The yield and N uptake of barley grain was increased where fall-applied banded urea or aqua NH3 received banded CS2, (NH4)2CS3, or K2CS3. The average increase in yield from fall-applied fertilizer, from inhibitor with fall-applied fertilizer, and from spring-applied
fertilizer was 800, 1370, and 1900 kg ha−1, respectively. In the same order, the apparent % recovery of fertilizer N in grain was 24, 42, and 60. 相似文献
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Spatial distributions of individuals may be considered in two ways: Firstly, individuals are situated on a continuum. Secondly, individuals are situated on discrete units, for example, insect eggs on plants. The aim of this paper is to show that sometimes, in the latter case, sampling methods based on infestation runs can be of interest in estimating population density. Analytical results are obtained under complete spatial randomness hypothesis and alternative hypotheses. Sampling procedures with limited cost are discussed and the European corn borer (ECB) case is mainly considered. 相似文献
10.