Comparative Population Genetics of Fusarium Graminearum and Novel Sources of Resistance to Fusarium Head Blight in Spring Wheat

Fusarium graminearum is the major causal agent of Fusarium head blight (FHB) in cereal crops. The fungus produces several types of trichothecenes [Deoxynivalenol (DON) and its acetylated derivatives, 3-acetyldeoxynivalenol (3ADON) and 15-acetyldeoxynivalenol (15ADON), and nivalenol (NIV)]. Characterization of 123 isolates collected during 1980 to 2000 (old collection), and 43 isolates collected in 2008 (new collection) from North Dakota revealed that 15ADON producing isolates were predominant (98%) in the old collection while the 3ADON producing isolates accounted for 43% in the new collection. Further, evaluation showed that the 3ADON isolates caused a higher disease severity and accumulated more DON in spring wheat than the 15ADON isolates. The 3ADON also exhibited higher DON in rice culture, and produced more spores on agar media. Population genetic analyses revealed a significant genetic differentiation between the two populations. To elucidate the transcriptomic differences between the two populations in vitro and in planta, RNA-sequencing was used. The in vitro gene expression comparison identified 479 up- and 801 down- regulated genes in the 3ADON population compared to 15ADON population. The in planta pair-wise comparisons between the two populations revealed 185, 89, and 62 unique genes to 3ADON at 48, 96 and 144 hours after inoculation (HAI), respectively. In a different study, population genetic analysis was conducted on 160 isolates collected in 2008 and 2009 from a FHB disease nursery located in China. All isolates analyzed were F. asiaticum except one (F. avenaceum). Of the 159 isolates, 79% were NIV producing, 18% were 15ADON and 3% were 3ADON. The two populations grouped based on year of collection exhibited low genetic differentiation (Fst = 0.032). To identify new sources of FHB resistance, 71 wheat accessions of diverse origins were re-evaluated for FHB severity and haplotyped using seventeen DNA markers associated with known resistance quantitative trait loci (QTL). Twenty two accessions had a haplotype different from all known sources used, suggesting that they may carry novel loci for FHB resistance. In conclusion, the information obtained in this study could have an impact on development of effective disease management measures and on improvement of FHB resistance in wheat.U.S. WheatBarley Scab InitiateArt Lamey Graduate Student ScholarshipBain Frank Graduate Student Scholarship from NDSUKenneth and Betty Barker AwardStuart D. Lyda Award from American Phytopathological Societ

Spectrophotometric Determination of Ru(III) & Os(VIII) with Acetothioacetanilide

917-91

Studies of multichannel rotational predissociation of Ar–H2 van der Waals molecule by the complexcoordinate coupledchannel formalism

This is the published version, also available here: http://dx.doi.org/10.1063/1.442929.The complex‐coordinate coupled‐channel (CCCC) formalism previously developed [J. Chem. Phys. 72, 4772 (1980)] is applied to the accurate determination of the level widths (lifetimes) and energies of rotationally predissociating metastable Ar⋅⋅⋅H2 van der Waals molecules. Calculations are performed using several realistic anisotropic potentials obtained recently by experiments, including Lennard‐Jones (LJ), Buckingham–Corner (BC) type potentials, as well as the semiempirical potential of Tang–Toennies (TT). New numerical methods are introduced here to deal with the complex rotations of piecewise inhomogeneous potentials such as those of BC and TT. It is found that the CCCC method is capable of providing reliable results for any given potential surface. Furthermore, the CCCC results are sensitive to the potential surfaces used. For example, the linewidths predicted for different LJ potential surfaces considered here vary by a factor as large as 4. However, the agreement among more recent potentials, namely, the BC potential of Zandee and Reuss and that of Le Roy and Carley as well as the potential of Tang and Toennies, is much closer: the resonance energies agree to within 1 cm−1 and the linewidths to within 30%

On Brewster's bands. Part I

The paper considers the explanation of Brewster's bands and other allied phenomena from the new and very suggestive standpoint proposed by schuster (Phil. Mag. Oct. 1924). When monochromatic light is reflected by or transmitted through two parallel plates in succession, we have a superposition of the haidinger ring-systems due to the two plates in the sense that the observed intensity in any given direction is the product of the intensities due to either plate separately. Illustrations showing the effect of such superposition in various cases are reproduced with the paper, differential and summational fringe-systems of various orders being observable. When non-homogeneous light is used, the Haidinger rings disappear and along with them also the superposition pattern, leaving only a uniform illumination in the field, except in the special case of the differential system of the first order for two plates of equal thickness. A simple geometrical explanation is thus forthcoming why Brewster's bands can be observed even in non-homogeneous light with thick plates in this case

Two‐photon dissociation of vibrationally excited HD+: The inhomogeneous differential equation approach

This is the published version, also available here: http://dx.doi.org/10.1063/1.451229.We extend the inhomogenous‐differential‐equation (IDE) approach of Dalgarno and Lewis for a detailed study of two‐photon dissociation (TPD) of HD+ from high vibrational levels of the 1sσ g electronic state. Contrary to the H+ 2 case, where the TPD cross sections σ(2) L are largest near TPD thresholds and decrease monotonically with increasing photon energy, the HD+ cross sections are characterized by rich resonant and interference structures. We present σ(2) L results for TPD from the initial v i =6, 8, 10, 12, 14, 16, and j i =0 levels as well as from v i =14, j i =0, 2, 4 levels for a wide range of wavelengths of linearly polarized radiation accessible by CO2 and CO lasers. It is found that while there are four TPD pathways, the channel 1sσ g (v i   j i )→ω 1sσ g (v, j=j i ±1) →ω2pσ u (k, j   f =j±1) dominates the two‐photon process in most of the cases we have studied. Further, the results show that σ(2) L increases rather rapidly as the initial vibrational quantum number v i increases, indicating that the hereronuclear diatomic molecules in high vibrational levels can be efficiently two‐photon dissociated by IR lasers. Consequently molecular structures near the dissociation limit may be conveniently probed by two‐photon spectroscopy—as has indeed been demonstrated recently by experiments. Our σ(2) L results thus provide complementary information to the HD+spectroscopic data obtained recently by Carrington e t a l

Nickel(II) & Copper(II) Complexes of 5(3)-Methyl-pyrazole-3(5)-carboxamide

744-74

Management of saltwater intrusion using 3D numerical modelling: a first for Pacific Island country of Vanuatu

Small island countries like Vanuatu are facing the brunt of climate change, sea level rise (SLR), tropical cyclones, and limited or declining access to freshwater. The Tagabe coastal aquifer in Port Vila (the capital of Vanuatu) shows the presence of salinity, indicating saltwater intrusion (SWI). This study aims to develop and evaluate effective SWI management strategies for Tagabe coastal aquifer. To manage SWI, the numerical simulation model for the study area was developed using the SEAWAT code. The flow model was developed using MODFLOW and the transport model was developed using MT3DMS. Whereby SEAWAT solved flow and transport equations simultaneously. The model was calibrated, and different scenarios were evaluated for the management of SWI. The SLR was also considered in the model simulations. The results indicated that increased population, pumping rates, and SLR affect the SWI rates. To manage the SWI, we introduced hydraulic barriers like barrier wells and injection wells which effectively managed SWI in Tagabe coastal aquifer. The results from this study are significantly important whereby, the water managers, site owners, and governing bodies can use the management strategies presented in this study to create policies and regulations for managing SWI rates in Port Vila. Additionally, the water industry, private businesses, and investors who wish to extract groundwater from the Tagabe can use this study as a reference for daily or yearly freshwater production rates without the risk of SWI

Quantum dynamics of molecular multiphoton excitation in intense laser and static electric fields: Floquet theory, quasienergy spectra, and application to the HF molecule

This is the published version, also available here: http://dx.doi.org/10.1063/1.444219.The multiphoton excitationdynamics of vibration‐rotation states in diatomic molecules in intense laser and static electric fields is investigated. The Floquet matrix method is used to calculate the quasienergy and multiphoton absorptionspectra of the HF molecule as functions of field strengths and frequency. Nonlinear effects such as power broadening, dynamic Stark shift, Autler–Townes multiplet splitting, hole burning, and S‐hump behaviors, etc., are observed and discussed in terms of quasienergy diagrams. Many of the salient features in the spectral line shapes may be qualitatively understood in terms of an analytical three‐level model. The addition of a dc electric field removes the restriction of the rotational dipole selection rule and causes significant intermixing of the bare molecular vibrator states. Due to the greater number of strongly coupled nearby states in the dc field, nonlinear effects such as those mentioned above appear at a much lower ac field strength than they would in the absence of the dc field. The introduction of an external dc field, therefore, strongly enhances the multiphoton excitation probabilities and results in a much richer spectrum

Signatures of gaugino mass non-universality in cascade Higgs production at the LHC

Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest Higgs and the charged Higgses, two characteristic particles of an extended Higgs sector.Comment: 14 pages, 22 figure