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411.
Lucimara Chiari Lucas Koshy Naoe Newton Deniz Piovesan Inês Chamel José Cosme Damião Cruz Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Euphytica》2006,150(1-2):141-147
Summary We studied the genetic basis of isoflavone content inheritance in soybean seeds. The progenitors BARC-8 (low isoflavone content), IAC-100 (high isoflavone content), the F1 and F2 populations derived from reciprocal crosses, and backcross populations were analyzed for isoflavone content and composition. Six isoflavones were detected: daidzin (DZ), genistin (GT), glycitin (GC), malonyldaidzin (MDZ), malonylgenistin (MGT) and malonylglycitin (MGC). DZ, GT, MDZ and MGT contents were influenced by the cytoplasm and the nuclear genes of the maternal parent. For this reason, a genetic model was considered that included the cytoplasmic effect and epistasis between nuclear and cytoplasmic genes. Except for GT, the additive effect was the most important one. For GT content the cytoplasmic effect was the most important. Except for MDZ, the epistatic effects were significant for all the isoflavone forms. Our data indicate that genetic improvement for these traits should explore the additive genetic variances in superior lines or the cytoplasmic effect and the epistatic interactions between cytoplasmic and nuclear genes to obtain the largest selection gains. 相似文献
412.
Lucimara Chiari Newton Deniz Piovesan Lucas Koshy Naoe Inês Chamel José José Marcelo Soriano Viana Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Euphytica》2004,138(1):55-60
Isoflavones are a class of compounds present in high amounts in soybean seeds, which can be used for prevention and treatment
of several chronic diseases. Proteins present in soybean seeds are the basis for the high nutritional value and versatility
of this leguminous species in animal and human feeding. The main goals of this work were to estimate heritabilities for isoflavone
contents in soybean seeds and the correlation between isoflavone and protein contents. Commercial variety IAC-100 (high isoflavone
and normal protein contents) and the line BARC-8 (low isoflavone and high protein contents) were crossed, and one single F1 plant derived 97 F2 seeds, which were used to obtain F3 seeds. A sample of F3 seeds from each F2 plant was used for isoflavone determination by HPLC and protein by the Kjeldahl method. Six isoflavone forms were detected:
daidzin, genistin, glycitin, malonyldaidzin, malonylgenistin and malonylglycitin. Total isoflavone contents ranged from 427.92
to 965.89 μg per gram of dry seed and the protein content ranged from 45.17 to 34.95% in BARC-8 and IAC-100, respectively.
Our results indicate that it is possible to select for high isoflavone content in early breeding generations because the broad
sense heritabilities for the contents of the various isoflavone forms were higher than 90%. In addition, high correlation
values among the contents of the individual isoflavone forms were observed (between 0.80 and 0.98). However, negative correlation
values were obtained between isoflavone and protein contents, ranging from −0.51 to −0.37 for the different isoflavone forms.
The correlation value of −0.47 between total isoflavone and protein contents confirmed the negative correlation between these
two parameters, as reported by other authors.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
413.
The sequence of the Streptococcus equi subspecies equi (S equi) M-like protein (SeM) gene was determined for 105 isolates of S equi from strangles outbreaks in the UK during 2010 and compared with previous data from 2007 to 2008. Twenty-three distinct alleles were identified, including 11 novel alleles. One allele giving rise to a putative truncated M protein was identified from the guttural pouch of an asymptomatic carrier. Allele 9 was the most prevalent, comprising 57.7 per cent of isolates, followed by allele 6 (10.3 per cent). Significant changes in allele prevalence were found between 2007, 2008 and 2010, with an increasing prevalence in SeM-9-related alleles and a corresponding decreasing prevalence in SeM-6-related alleles observed over the period (P<0.001). Geographical proximity of outbreaks caused by some uncommon alleles was apparent between 2007, 2008 and 2010. 相似文献
414.
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416.
The increasing global demand for food production, often causing excessive use of chemical fertilizers, has led to the deterioration of soil health. Immediate action is required to restore soil health in a sustainable manner. This review advocates switching to use of organic matter(manure and compost) that contains vital nutrients for plant growth and helps restore soil health. Humic substances(HSs), derived from degraded plant remains and found ubiquitously in nature,are an important source of o... 相似文献
417.
Newton Z. Lupwayi Benjamin H. Ellert Eric Bremer Elwin G. Smith Renee M. Petri Jonathan A. D. Neilson H. Henry Janzen 《Soil Use and Management》2023,39(1):402-414
Variable results have been reported on the effects of crop residue loads on soil microbial properties. We investigated changes in soil bacterial composition, β-glucosidase enzyme activity and nutrient bioavailability in response to wheat residue loading. The treatments included three levels of above-ground wheat residues (removed, retained or supplemented), with or without fertilizer N. Bacteroidetes, Firmicutes and Verrucomicrobia (the first two are copiotrophs) were less abundant where residues were removed than where residues were retained or supplemented, but the reverse was true for Actinobacteria, Cyanobacteria, Chloroflexi and Nitrospirae (all oligotrophs, although some Actinobacteria can be copiotrophic). Actinobacteria were also less abundant where fertilizer N was applied, and the abundances of their genera (including Arthrobacter and Mycobacterium) increased where residues were removed, confirming that they were oligotrophic in this study. β-diversity showed similar differences in the bacterial community structures because of residue management, but α-diversity was not affected by residue management or N fertilizer. β-glucosidase enzyme activities increased as C inputs increased with residue manipulation and N fertilizer. The enzyme activities increased with increasing residue loading in the 0–15 cm soil depth, but decreased with soil depth. Soil K supply increased with increasing residue loading, but nitrate-N supply was highest with residue retention. These results demonstrate remarkable resilience of soil microbial functioning under a wide range of crop residue inputs, without adverse effects on enzyme activity attributable to inorganic N fertilizer. The increasing β-glucosidase activity with increasing residue loading probably explains why crop residue return does not always increase soil C stocks. 相似文献
418.
Cope Jonathan E. Norton Gareth J. George Timothy S. Newton Adrian C. 《植物病害和植物保护杂志》2021,128(4):999-1012
Journal of Plant Diseases and Protection - Barley ‘Scald’ is an economically damaging fungal disease that is a global problem, causing significant yield and economical losses in the UK... 相似文献
419.
Fabiola López-Barrera Robert H. Manson Mario González-Espinosa Adrian C. Newton 《Landscape Ecology》2007,22(2):189-203
Hard (high-contrast with pastures) and soft (low-contrast with old-fields) forest edges created by slash-and-burn agriculture
have become common landscape features in regions dominated by neotropical montane forest. However, little is know about the
impacts of such edge types on forest regeneration dynamics. The consequences of varying forest edge permeability for oak acorn
dispersal were investigated in a forest mosaic in the Highlands of Chiapas, Mexico. Rates of acorn production and removal,
as well as the abundance and composition of small mammal seed consumers, were monitored along these different edge types (hard
vs. soft) at specific distances from forest edges into forest patches and adjacent grasslands during two consecutive years.
Results show that acorn removal declined significantly only in grasslands of sites characterised by hard edges (Logistic regression,
P < 0.05). Movements of metal-tagged acorns support the hypothesis that soft edges are more permeable to small mammals, with
rodents moving acorns up to 15 m into grasslands of sites with soft edges. In sites with hard edges, higher rates of acorn
dispersal were recorded from the forest edge towards the forest interior. Peromyscus spp. were the main acorn predators and/or dispersers of acorns present in our study sites. Rates of acorn removal during
a non-masting year were greater than the subsequent mast-seeding year (85% removal within 138 days vs. 75% within 213 days),
demonstrating that mast seeding may allow some seeds to escape predation. The implications of these results for oak dispersal
and regeneration along edges in fragmented tropical forest landscapes are discussed. 相似文献
420.
Mauro Pivetta Luisa De Risio Richard Newton Ruth Dennis 《Veterinary radiology & ultrasound》2013,54(5):516-521
Asymmetry of the cerebral lateral ventricles is a common finding in cross‐sectional imaging of otherwise normal canine brains and has been assumed to be incidental. The purpose of this retrospective study was to compare the prevalence of ventricular asymmetry in brain MRI studies of normal dogs and dogs with idiopathic epilepsy. Brain MRI archives were searched for 100 neurologically normal dogs (Group 1) and 100 dogs with idiopathic epilepsy (Group 2). For each dog, asymmetry of the lateral ventricles was subjectively classified as absent, mild, moderate, and severe based on a consensus of two observers who were unaware of group status. Ventricular areas were measured from transverse T1W images at the level of the interthalamic adhesion. An asymmetry ratio was calculated as the ratio of the larger to smaller ventricular transverse area. There was excellent agreement between subjective assessments of ventricular asymmetry and quantitative assessments using asymmetry ratios (k = 0.995). The prevalence of asymmetry was 38% in Group 1 dogs and 44% in Group 2 dogs. Assymmetry was scored as mild in the majority of Group 2 dogs. There was no significant association between presence/absence and degree of ventricular asymmetry vs. dog group, age, gender, or skull conformation. Findings from the current study supported previously published assumptions that asymmetry of the lateral cerebral ventricles is an incidental finding in MRI studies of the canine brain. 相似文献