102 research outputs found
Evaluation of bio-physiological and yield responses of stay green QTL introgression sorghum lines to post-flowering drought stress
Drought is the most drastic abiotic stress that limits crop production
in sub-Sahara Africa. Sorghum ( Sorghum bicolor (L.) Moench) is among
the most climate resilient cereals of the future due to its tolerance
to drought and heat. Thus, identification of tolerant genotypes and
plant characteristics that contribute to drought adaptation is timely.
The objective of this study was to evaluate the response of 12
genotypes, including seven Stay-green (Stg) QTL introgression sorghum
lines and their two donor; and three recurrent parents, to induced
post-flowering drought stress. The recurrent parents were varieties
released for drought prone lowlands of the country, and the donor
parents were lines known to have stay-green properties. The study was
conducted at Werer, in the Great Rift-valley of Ethiopia, during the
off-season of 2014 under well-watered and water limited conditions.
Significant differences (P<0.05) were observed among genotypes under
water deficit regimes, for all measured physiological, biochemical
(proline content), yield and yield related traits. Three Stg QTL
introgression lines showed better tolerance to drought than their
recurrent parents, as reflected by yield and maintenance of green leaf
area. Three Stg QTL introgression lines, Teshale/E36-1, Gambella/B35-5
and Meko/B35-12, gave the highest grain yield under post-flowering
drought stress, and B35 and Teshale/B35 gave the poorest yield under
similar conditions. Therefore, these improved lines bear potential for
use as alternatives in breeding programmes and for possible release in
parts of the country where post-flowering drought stress is frequent.
Proline content, weight of hundred seeds (HSW) and CO2 assimilation are
effective screening tools for Stg property due to their high
correlation with other parameters.La s\ue8cheresse est le stress abiotique le plus drastique qui limite
la production agricole en Afrique Sub-saharienne. Le sorgho ( Sorghum
bicolor (L.) Moench) est parmi les c\ue9r\ue9ales les plus
r\ue9silientes au climat pour le futur d\ufb \ue0 sa
tol\ue9rance \ue0 la s\ue9cheresse et \ue0 la chaleur. Donc,
l\u2019identification des g\ue9notypes tol\ue9rants et les
caract\ue9ristiques des plants qui contribuent \ue0
l\u2019adaptation \ue0 la s\ue9cheresse est opportune.
L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer la
r\ue9ponse de 12 g\ue9notypes, comportant sept lign\ue9es de
sorgho conf\ue9rant l\u2019introgression des QTL des attributs verts
(Stg), leurs deux donneurs\ua0; et les trois parents r\ue9currents,
au stress de la s\ue9cheresse post floraison induite. Les parents
r\ue9currents ont \ue9t\ue9 les vari\ue9t\ue9s
lib\ue9r\ue9es sensibles \ue0 la s\ue9cheresse dans les plaines
du pays, et les donneurs ont \ue9t\ue9 les lign\ue9es connues
pour leurs propri\ue9t\ue9s relatives aux attributs verts.
L\u2019\ue9tude a \ue9t\ue9 conduite \ue0 Werer, dans la
grande vall\ue9e du Rift d\u2019Ethiopie, pendant la contre saison
de 2014 dans des conditions d\u2019irrigation abondante et
d\u2019irrigation limit\ue9e. De diff\ue9rences significatives
(P<0.05) ont \ue9t\ue9 observ\ue9es entre les g\ue9notypes
sous des r\ue9gimes de d\ue9ficit hydriques, pour tous les traits
physiologiques, biochimiques (teneur en proline), le rendement et les
composantes de rendement. Trois lign\ue9es d\u2019introgression de
Stg QTL ont montr\ue9 de meilleure tol\ue9rance \ue0 la
s\ue9cheresse que leurs parents r\ue9currents, comme
refl\ue9t\ue9 par le rendement et la maintenance de la surface
verte de la feuille. Trois lign\ue9es d\u2019introgression de Stg
QTL, Teshale/E36-1, Gambella/B35-5 et Meko/B35-12, ont donn\ue9 le
plus haut rendement sous le stress de s\ue9cheresse de post
floraison, et B35 et Teshale/B35 ont donn\ue9 le plus faible
rendement dans des conditions similaires. En cons\ue9quence, ces
lign\ue9es am\ue9lior\ue9es d\ue9tiennent tout le potentiel
pour leur usage comme alternatives dans des programmes
d\u2019am\ue9lioration g\ue9n\ue9tiques et pour une
lib\ue9ration possible dans les r\ue9gions du pays o\uf9 le
stress de la s\ue9cheresse post floraison est fr\ue9quent. La
teneur en proline, le poids de 100 graines (HSW) et
l\u2019assimilation du CO2 sont des outils effectifs de criblage pour
la propri\ue9t\ue9 de Stg due \ue0 leur forte corr\ue9lation
avec les autres param\ue8tres
Shock and patient preimplantation type D personality are associated with poor health status in patients with implantable cardioverter-defibrillator
Background: Implantable cardioverter-defibrillator (ICD) shock is a critical event to patients associated with well-being after implantation, although other factors may play an equally important role. We compared the association of shock and the patient's preimplantation personality with health status, using a prospective study design.
Methods and Results: Consecutively implanted ICD patients (n=383; 79% men) completed the Type D Scale at baseline and the Short-Form Health Survey 36 (SF-36) at baseline and 3, 6, and 12 months. Of all patients, 23.5% had a Type D personality and 13.8% received a shock during follow-up. Shocked patients reported significantly poorer health status, as did Type D patients. Health status patterns were poorest in patients with combined Type D personality and shock during follow-up. Shock during follow-up was a significant independent associate of poorer health status for 4 of 8 subscales of the SF-36 and the Mental Component Summary (all P<.05), with shocked patients scoring between 2.60 to 13.30 points lower than nonshocked patients. Type D personality was an independent associate of poor postimplantation health status for 6 of 8 of the SF-36 subscales and the Mental Component Summary, with Type D patients scoring between 2.12 to 8.02 points lower, adjusting for demographic and clinical characteristics.
Conclusions: ICD shock and the patient's preimplantation personality disposition were equally important associates of health status 12 months after implantation. Identification of the patient's personality profile before ICD implantation may help identify subsets of patients who may need additional care, for example, with a psychosocial component
Study of growth and physiological characters in stay-green QTL introgression Sorghum bicolor (L.) lines under post-flowering drought stress
This experiment was carried out to evaluate the growth, physiological and yield traits of stay-green (Stg) QTL introgression sorghum lines, which were developed by the Ethiopian Institute of Agricultural Research in collaboration with ICRISAT between 2006 and 2008, under induced post-flowering drought stress. It involved a total of 12 genotypes including seven Stg QTL introgression lines, two Stg donor parents and three senescent recurrent parents. It was organized in a split plot design with three replications under well-watered and induced drought stress growing conditions at Melka Werer, Ethiopia during the post-rainy season of 2014. Analysis of variance revealed that the effect of moisture regimes on all measured traits was significant (P > 0.05). Differences among the genotypes and genotypeby- water regime interaction were also significant (P > 0.05) for all the traits considered. Postflowering drought stress was observed to significantly reduce most of the growth, physiological and yield related traits. The Stg introgression lines Meko/B35-selection 120, Teshale/B35-selection 2 and Teshale/E36-1 showed better drought stress tolerance properties than the rest of the genotypes based on the measured growth and physiological traits. These introgression lines also showed better grain yield than their recurrent parents under post-flowering drought stress and can be used as new versions of the existing varieties (served as recurrent parents) and for future breeding programs. Furthermore, leaf chlorophyll content, assimilation rate, transpiration rate, water use efficiency, root length and root dry weight were found to have strong correlation and can be used to screen genotypes for post-flowering drought tolerance
Genetic diversity and association mapping of Ethiopian and exotic finger millet accessions
Combining morphological and molecular data to identify genetic variation and marker–trait association is one of the most important prerequisites for genomics-assisted selection in crop improvement. To this end, a total of 138 finger millet (Eleusine coracana subsp. coracana) accessions including five improved varieties were evaluated to assess the genetic variation and population structure and undertake association mapping. These accessions were basically collected from Ethiopia (96), Eritrea (8), Kenya (7), Zambia (9) and Zimbabwe (13). Finger millet accessions were evaluated in the field for 10 important agronomic traits and also characterised using a set of 20 microsatellite markers. Mean polymorphism information content of 0.61 was observed from a total of 222 alleles with an average of 11.1 alleles per microsatellite locus. About 61% of alleles detected were rare (<5%) and specific allele amplification was observed in 34 accessions. Both weighted neighbour-joining based clustering using molecular data and hierarchical clustering using phenotypic trait data grouped the 138 accessions into four major clusters that were not entirely based on their geographical origins. Genome-wide association studies depicted 16 significant (P < 0.01) associations between 13 microsatellite markers and six agronomic traits. Our results reveal a unique abundance of rare alleles in finger millet and highlight the need for more careful selection of genome-wide association studies in the future in order to capture the contribution of rare alleles to important agronomic traits
Affordable and robust phenotyping framework to analyse root system architecture of soil-grown plants
The phenotypic analysis of root system growth is important to inform efforts to enhance plant resource acquisition from soils. However, root phenotyping still remains challenging due to soil opacity, requiring systems that facilitate root system visibility and image acquisition. Previously reported systems require costly or bespoke materials not available in most countries, where breeders need tools to select varieties best adapted to local soils and field conditions. Here, we report an affordable soil‐based growth (rhizobox) and imaging system to phenotype root development in greenhouses or shelters. All components of the system are made from locally available commodity components, facilitating the adoption of this affordable technology in low‐income countries. The rhizobox is large enough (~6000 cm2 visible soil) to not restrict vertical root system growth for most if not all of the life cycle, yet light enough (∼21 kg when filled with soil) for routine handling. Support structures and an imaging station, with five cameras covering the whole soil surface, complement the rhizoboxes. Images are acquired via the Phenotiki sensor interface, collected, stitched and analysed. Root system architecture (RSA) parameters are quantified without intervention. RSA of a dicot (chickpea, Cicer arietinum L.) and a monocot (barley, Hordeum vulgare L.) species, which exhibit contrasting root systems, were analysed. Insights into root system dynamics during vegetative and reproductive stages of the chickpea lifecycle were obtained. This affordable system is relevant for efforts in Ethiopia and other low‐ and middle‐income countries to sustainably enhance crop yields and climate resilience
Diagnostic efficiency of abattoir meat inspection service in Ethiopia to detect carcasses infected with Mycobacterium bovis: Implications for public health
Global, regional, and national burden of chronic kidney disease, 1990–2017 : a systematic analysis for the Global Burden of Disease Study 2017
Background
Health system planning requires careful assessment of chronic kidney disease (CKD) epidemiology, but data for morbidity and mortality of this disease are scarce or non-existent in many countries. We estimated the global, regional, and national burden of CKD, as well as the burden of cardiovascular disease and gout attributable to impaired kidney function, for the Global Burden of Diseases, Injuries, and Risk Factors Study 2017. We use the term CKD to refer to the morbidity and mortality that can be directly attributed to all stages of CKD, and we use the term impaired kidney function to refer to the additional risk of CKD from cardiovascular disease and gout.
Methods
The main data sources we used were published literature, vital registration systems, end-stage kidney disease registries, and household surveys. Estimates of CKD burden were produced using a Cause of Death Ensemble model and a Bayesian meta-regression analytical tool, and included incidence, prevalence, years lived with disability, mortality, years of life lost, and disability-adjusted life-years (DALYs). A comparative risk assessment approach was used to estimate the proportion of cardiovascular diseases and gout burden attributable to impaired kidney function.
Findings
Globally, in 2017, 1·2 million (95% uncertainty interval [UI] 1·2 to 1·3) people died from CKD. The global all-age mortality rate from CKD increased 41·5% (95% UI 35·2 to 46·5) between 1990 and 2017, although there was no significant change in the age-standardised mortality rate (2·8%, −1·5 to 6·3). In 2017, 697·5 million (95% UI 649·2 to 752·0) cases of all-stage CKD were recorded, for a global prevalence of 9·1% (8·5 to 9·8). The global all-age prevalence of CKD increased 29·3% (95% UI 26·4 to 32·6) since 1990, whereas the age-standardised prevalence remained stable (1·2%, −1·1 to 3·5). CKD resulted in 35·8 million (95% UI 33·7 to 38·0) DALYs in 2017, with diabetic nephropathy accounting for almost a third of DALYs. Most of the burden of CKD was concentrated in the three lowest quintiles of Socio-demographic Index (SDI). In several regions, particularly Oceania, sub-Saharan Africa, and Latin America, the burden of CKD was much higher than expected for the level of development, whereas the disease burden in western, eastern, and central sub-Saharan Africa, east Asia, south Asia, central and eastern Europe, Australasia, and western Europe was lower than expected. 1·4 million (95% UI 1·2 to 1·6) cardiovascular disease-related deaths and 25·3 million (22·2 to 28·9) cardiovascular disease DALYs were attributable to impaired kidney function.
Interpretation
Kidney disease has a major effect on global health, both as a direct cause of global morbidity and mortality and as an important risk factor for cardiovascular disease. CKD is largely preventable and treatable and deserves greater attention in global health policy decision making, particularly in locations with low and middle SDI
Nitrogen Level Changes the Interactions between a Native (Scirpus triqueter) and an Exotic Species (Spartina anglica) in Coastal China
The exotic species Spartina anglica, introduced from Europe in 1963, has been experiencing a decline in the past decade in coastal China, but the reasons for the decline are still not clear. It is hypothesized that competition with the native species Scirpus triqueter may have played an important role in the decline due to niche overlap in the field. We measured biomass, leaf number and area, asexual reproduction and relative neighborhood effect (RNE) of the two species in both monoculture and mixture under three nitrogen levels (control, low and high). S. anglica showed significantly lower biomass accumulation, leaf number and asexual reproduction in mixture than in monoculture. The inter- and intra-specific RNE of S. anglica were all positive, and the inter-specific RNE was significantly higher than the intra-specific RNE in the control. For S. triqueter, inter- and intra-specific RNE were negative at the high nitrogen level but positive in the control and at the low nitrogen level. This indicates that S. triqueter exerted an asymmetric competitive advantage over S. anglica in the control and low nitrogen conditions; however, S. anglica facilitated growth of S. triqueter in high nitrogen conditions. Nitrogen level changed the interactions between the two species because S. triqueter better tolerated low nitrogen. Since S. anglica is increasingly confined to upper, more nitrogen-limited marsh areas in coastal China, increased competition from S. triqueter may help explain its decline
Disentangling the Pure Time Effect From Site and Preference Heterogeneity Effects in Benefit Transfer: An Empirical Investigation of Transferability
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