scholarly journals Resistance Gene Mapping for Witches' Broom Disease in Theobroma cacao L. in an F2 Population using SSR Markers and Candidate Genes

2005 ◽  
Vol 130 (3) ◽  
pp. 366-373 ◽  
Author(s):  
J. Steven Brown ◽  
R.J. Schnell ◽  
J.C. Motamayor ◽  
Uilson Lopes ◽  
David N. Kuhn ◽  
...  

A genetic linkage map was created from 146 cacao trees (Theobroma cacao), using an F2 population produced by selfing an F1 progeny of the cross Sca6 and ICS1. Simple sequence repeat (SSR) markers (170) were used principally for this map, with 12 candidate genes [eight resistance gene homologues (RGH) and four stress related WRKY genes], for a total of 182 markers. Joinmap software was used to create the map, and 10 linkage groups were clearly obtained, corresponding to the 10 known chromosomes of cacao. Our map encompassed 671.9 cM, approximately 100 cM less than most previously reported cacao maps, and 213.5 cM less than the one reported high-density map. Approximately 27% of the markers showed significant segregation distortion, mapping together in six genomic areas, four of which also showed distortion in other cacao maps. Two quantitative trait loci (QTL) for resistance to witches' broom disease were found, one producing a major effect and one a minor effect, both showing important dominance effects. One QTL for trunk diameter was found at a point 10.2 cM away from the stronger resistance gene. One RGH flanked the minor QTL for witches' broom resistance, implying possible association. QTLs mapped in F2 populations produce estimates of additive and dominance effects, not obtainable in F1 crosses. As dominance was clearly shown in the QTL found in this study, this population merits further study for evaluation of dominance effects for other traits. This F2 cacao population constitutes a useful link for genomic studies between cacao and cotton, its only widely grown agronomic relative.

2007 ◽  
Vol 7 (12) ◽  
pp. 3361-3372 ◽  
Author(s):  
J. Rinne ◽  
R. Taipale ◽  
T. Markkanen ◽  
T. M. Ruuskanen ◽  
H. Hellén ◽  
...  

Abstract. We measured the fluxes of several hydrocarbon species above a Scots pine (Pinus sylvestris) stand using disjunct eddy covariance technique with proton transfer reaction – mass spectrometry. The measurements were conducted during four days in July at SMEAR II research station in Hyytiälä, Finland. Compounds which showed significant emission fluxes were methanol, acetaldehyde, acetone, and monoterpenes. A stochastic Lagrangian transport model with simple chemical degradation was applied to assess the sensitivity of the above canopy fluxes to chemistry. According to the model, the chemical degradation had a minor effect on the fluxes measured in this study but may have a major effect on the vertical flux profiles of more reactive compounds, such as sesquiterpenes. The monoterpene fluxes derived using M81 and M137 had a systematic difference with the latter one being higher. These fluxes followed the traditional exponential temperature dependent emission algorithm but were considerably higher than the fluxes measured before at the same site. The normalized monoterpene emission potentials at 30°C, obtained using the temperature dependence coefficient of 0.09°C−1, were 2.0 μg gdw−1 h−1 and 2.5 μg gdw−1 h−1, for fluxes derived using M81 and M137.


BMC Genomics ◽  
2016 ◽  
Vol 17 (1) ◽  
Author(s):  
Stefan Royaert ◽  
Johannes Jansen ◽  
Daniela Viana da Silva ◽  
Samuel Martins de Jesus Branco ◽  
Donald S. Livingstone ◽  
...  

1987 ◽  
Vol 33 (2) ◽  
pp. 138-141 ◽  
Author(s):  
L. L. Davis ◽  
A. B. A. M. Baudoin

In liquid cultures of Geotrichum candidum, amended with KCl, mannitol, or polyethylene glycol 400 to control osmotic potential, levels of both intracellular and extracellular endopolygalacturonase fell off rapidly with decreasing osmotic potential in the range of −0.5 to −2.5 MPa. Concentrations (units per millilitre) of intracellular endopolygalacturonase were higher than those of extracellular endopolygalacturonase at all osmotic potentials tested. The ratio of intracellular to extracellular endopolygalacturonase concentration increased with decreasing osmotic potential; this became most pronounced below −1.5 MPa. It appeared that the major effect of osmotic potential was on endopolygalacturonase synthesis with a minor effect on endopolygalacturonase secretion from the cell. Levels of intracellular and extracellular cellulase also decreased with decreasing osmotic potential, although the effect was much smaller than with endopolygalacturonase. However, the ratio of intracellular to extracellular cellulase concentration did not change significantly with changes in osmotic potential. This indicated that only the synthesis of cellulase was affected.


1996 ◽  
Vol 12 (4) ◽  
pp. 449-469 ◽  
Author(s):  
Steven M. Nesbit ◽  
Terry A. Hartzell ◽  
John C. Nalevanko ◽  
Ryan M. Starr ◽  
Mathew G. White ◽  
...  

This paper discusses the inertia tensors of iron golf club heads and their influence on the swing of a golfer and the behavior of the golf club. Inertia tensors of various five-iron club head configurations were determined using solid modeling and were compared with equivalent solid ellipsoids. A golf swing and club behavior analysis was performed using a computer model comprised of a 3D parametric flexible model of a golf club driven with data from a recorded golf swing, and an impact function. The impact results were verified experimentally. The analysis without impact determined that altering club head inertia had a minor effect on the torque required to swing the club and the deflections of the club head at the time of impact. The analysis with an eccentric impact found that altering club head inertia had a major effect on transmitted forces and torques and a moderate effect on deflection of the club head.


1940 ◽  
Vol 24 (2) ◽  
pp. 169-188 ◽  
Author(s):  
Anthony J. Glazko ◽  
John H. Ferguson

1. A new technique for studying the progressive inactivation of thrombin is described. 2. Thrombin inactivation follows the kinetics of a first order reaction. 3. The rate constant of the inactivation reaction increases with temperature and pH (5.0 → 10.0), and also with the presence of crystalline trypsin, or serum. The rate varies for different thrombin preparations, even under the same experimental conditions. 4. The temperature characteristics of the reaction indicate that thrombin is associated with protein. 5. Thrombin preparations are most stable at pH 4 to 5, even when trypsin or serum is added. 6. The progressive inactivation is believed to be due to two mechanisms: (1) a major effect, thought to be the action of a "serum-tryptase," which is usually present in the thrombin preparations, and (2) a minor effect, probably attributable to denaturation of thrombin-protein. 7. Sources of the thrombinolytic factor (serum-tryptase) and its implications in the general theory and practical problems of blood coagulation and antithrombic action are briefly discussed.


2014 ◽  
Vol 6 ◽  
pp. IJIS.S20688 ◽  
Author(s):  
Charles S. Burks

The navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), is a key pest of high-value irrigated nut crops in the arid Central Valley of California. Mating disruption is an established pest management technique for this pest, with reduced non-target impacts. This study compared laboratory survivorship and fertility data with field measurements to improve understanding of factors determining abundance of this species in the presence and absence of mating disruption. While the relative humidity is generally higher in almond orchards compared to readings from meteorological stations, the data indicate little free water in the absence of irrigation. Access to free water has a minor effect on the fertility of females if they mate soon after emergence, but a major effect if mating is delayed for 7 days. Leslie matrix projections indicate that changes in adult survivorship have much less impact than changes in larval survivorship. These findings indicate that control tactics limiting reproduction and survival of immature stages are more important for this species than those targeting adults.


2018 ◽  
Author(s):  
Casper J Albers ◽  
Carlien Vermue ◽  
Taco de Wolff ◽  
Hans Beldhuis

Many higher education institutions use a policy for academic dismissal. In the Netherlands, the academic dismissal policy is such that students with fewer credits than a certain threshold after their first year, are expelled. This article employs the beta-binomial model to assess whether this method succeeds in filtering those who have potential from those who do not and what the optimal level of the threshold is. The model considers 13,234 students in three consecutive cohorts from around fifty different bachelor's degree programmes at the University of Groningen. We found that demanding 45 out of 60 credits constitutes a fair threshold for this institution. Although a strict dismissal policy has only a minor effect on cohorts, it can have a major effect on specific groups of students. The software employed here is made available.


2007 ◽  
Vol 7 (1) ◽  
pp. 2357-2388 ◽  
Author(s):  
J. Rinne ◽  
R. Taipale ◽  
T. Markkanen ◽  
T. M. Ruuskanen ◽  
H. Hellén ◽  
...  

Abstract. We measured the fluxes of several hydrocarbon species above a Scots pine (Pinus sylvestris) stand using disjunct eddy covariance technique with proton transfer reaction – mass spectrometry. The measurements were conducted during four days in July at SMEAR II research station in Hyytiälä, Finland. Compounds which showed significant emission fluxes were methanol, acetaldehyde, acetone, and monoterpenes. A stochastic Lagrangian transport model with simple chemical degradation was applied to assess the sensitivity of the above canopy fluxes to chemistry. According to the model, the chemical degradation had a minor effect on the fluxes measured in this study but has a major effect on the vertical flux profiles of more reactive compounds, such as sesquiterpenes. The monoterpene fluxes followed the traditional exponential temperature dependent emission algorithm but were considerably higher than the fluxes measured before at the same site. The normalized emission potential (30°C) was 2.5 μg gdw–1 h−1 obtained using the temperature dependence coefficient of 0.09°C−1.


1995 ◽  
Vol 386 ◽  
Author(s):  
A. L. P. Rotondaro ◽  
T. Q. Hurd ◽  
H. F. Schmidt ◽  
I. Teerlinck ◽  
M. M. Heyns ◽  
...  

ABSTRACTThe outplating behaviour of Fe and Cu was investigated for diluted solutions of HCl and HNO3. The deposition of the metallic contaminants was found to be strongly dependent on the type of surface that is exposed to the contaminated solution. Cu deposits heavily on bare silicon surfaces, whereas only low levels of Fe deposition are observed. On the other hand, on thermal oxide surfaces, the levels of deposited Fe are consistently higher than the Cu ones. The acid used appears to have no major impact on the deposition process. The pH of the solutions has a major effect on the Cu deposition and a minor effect on the Fe case.


2020 ◽  
Author(s):  
Kavitha Kurup ◽  
Stephanie Matyi ◽  
Cory B. Giles ◽  
Jonathan D. Wren ◽  
Kenneth Jones ◽  
...  

AbstractThe effect of calorie restriction (CR) on the microbiome, fecal metabolome, and colon transcriptome of adult and old male mice was compared. Life-long CR increased microbial diversity and the Bacteriodetes/Fermicutes ratio and prevented the age-related changes in the microbiota, shifting it to a younger microbial and fecal metabolite profile in both C57BL/6JN and B6D2F1 mice. Old mice fed CR were enriched in the Rikenellaceae, S24-7 and Bacteroides families. The changes in the microbiome that occur with age and CR were initiated in the cecum and further modified in the colon. Short-term CR in adult mice had a minor effect on the microbiome but a major effect on the transcriptome of the colon mucosa. These data suggest that the primary impact of CR is on the physiological status of the gastrointestinal system, maintaining it in a more youthful state, which in turn results in a more diverse and youthful microbiome.


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