An Integrated Approach to Control Sclerotinia Stem Rot (White Mold) in Soybean

While brown stem rot, Phytophthora root rot, sudden death syndrome and the soybean cyst nematode generally are regarded as the most significant diseases of soybean in the North Central States, Sclerotinia stem rot, also called white mold, has been a problem in Minnesota, Wisconsin and Michigan for many years. Beginning in 1992, and again in 1994, Sclerotinia stem rot developed throughout the northern range of the North Central Region. Nationally, the disease is considered to be minor because it has not involved a high percentage of the national soybean acreage. Possibly this situation has changed and Sclerotinia stem rot will be an annual threat to soybean production in more of the Region. Chamberlain (1951) was the first to make a detailed report on Sclerotinia stem rot in the mid-west after he observed localized, but severe outbreaks of the disease in lllinois in 1946. Chamberlain (1951) summarized his findings by the following quote; \u27There appears to be no ready explanation as to why Sclerotinia stem rot, certainly one of the least prevalent of soybean diseases, can cause such severe but localized damage . After almost 50 years, more is known about factors that impact on the incidence and severity of this disease, but an element of mystery still remains as to why sudden outbreaks occur

Influence of Aphanomyces Root Rot on Alfalfa Health and Forage Yields

Maximum alfalfa performance is achieved when grown on deep, well drained soils, while severe stand and yield losses can occur on soils that are imperfectly drained (Wing, 1909; Alva et al., 1985). In Wisconsin, nearly half of all forage production is on soils that are classified as somewhat poorly drained

Recent study brings good news about the soybean aphid

Increased activity of bean leaf beetles and soybean aphids in Iowa soybean fields has challenged many of us over the last five years. Not just because of the sap feeding and leaf defoliation that can cause significant yield loss but also because we are dealing with another yield robber that we often can\u27t see. Iowa soybean fields can be infected with bean pod mottle and soybean {m}osaic viruses that are transmitted by bean leaf beetles and soybean aphids, respectively. The challenge that we are dealing with is, first of all, we can\u27t always see that we have a virus in soybean, and yield loss caused by viruses can occur even when symptoms are not apparent

Main and epistatic loci studies in soybean for Sclerotinia sclerotiorum resistance reveal multiple modes of resistance in multi-environments

Genome-wide association (GWAS) and epistatic (GWES) studies along with expression studies in soybean [Glycine max (L.) Merr.] were leveraged to dissect the genetics of Sclerotinia stem rot (SSR) [caused by Sclerotinia sclerotiorum (Lib.) de Bary], a significant fungal disease causing yield and quality losses. A large association panel of 466 diverse plant introduction accessions were phenotyped in multiple field and controlled environments to: (1) discover sources of resistance, (2) identify SNPs associated with resistance, and (3) determine putative candidate genes to elucidate the mode of resistance. We report 58 significant main effect loci and 24 significant epistatic interactions associated with SSR resistance, with candidate genes involved in a wide range of processes including cell wall structure, hormone signaling, and sugar allocation related to plant immunity, revealing the complex nature of SSR resistance. Putative candidate genes [for example, PHYTOALEXIN DEFFICIENT 4 (PAD4), ETHYLENE-INSENSITIVE 3-LIKE 1 (EIL3), and ETHYLENE RESPONSE FACTOR 1 (ERF1)] clustered into salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) pathways suggest the involvement of a complex hormonal network typically activated by both necrotrophic (ET/JA) and biotrophic (SA) pathogens supporting that S. sclerotiorum is a hemibiotrophic plant pathogen

PHENIX upgrade: Novel stripixel detector for heavy quark detection and proton spin structure measurements at RHIC energies

New design of silicon stripixel sensor has been developed at BNL for PHENIX upgrade. The sensor is a single-sided, DC-coupled, two-dimensional position sensitive device with good position resolution. This design is simpler for sensor fabrication and signal processing than the conventional double-sided strip sensor. HPK has produced pre-production stripixel sensors with thickness of 625 μm. The quality assurance tests show that the very low leakage current 0.12 nA per strip allows the use of the SVX4 chip. A long term stability test shows that the leakage current is stable over a long period of time. The study of the effects of irradiation on the performance of the stripixel sensor has been made using p+p collisions at 200 GeV at PHENIX, 14 MeV neutron and 20 MeV proton beams

First-principles study of the inversion thermodynamics and electronic structure of FeM2X4 (thio)spinels (M = Cr, Mn, Co, Ni; X = O, S)

FeM2X4 spinels, where M is a transition metal and X is oxygen or sulfur, are candidate materials for spin filters, one of the key devices in spintronics. We present here a computational study of the inversion thermodynamics and the electronic structure of these (thio)spinels for M = Cr, Mn, Co, Ni, using calculations based on the density functional theory with on-site Hubbard corrections (DFT+U). The analysis of the configurational free energies shows that different behaviour is expected for the equilibrium cation distributions in these structures: FeCr2X4 and FeMn2S4 are fully normal, FeNi2X4 and FeCo2S4 are intermediate, and FeCo2O4 and FeMn2O4 are fully inverted. We have analyzed the role played by the size of the ions and by the crystal field stabilization effects in determining the equilibrium inversion degree. We also discuss how the electronic and magnetic structure of these spinels is modified by the degree of inversion, assuming that this could be varied from the equilibrium value. We have obtained electronic densities of states for the completely normal and completely inverse cation distribution of each compound. FeCr2X4, FeMn2X4, FeCo2O4 and FeNi2O4 are half-metals in the ferrimagnetic state when Fe is in tetrahedral positions. When M is filling the tetrahedral positions, the Cr-containing compounds and FeMn2O4 are half-metallic systems, while the Co and Ni spinels are insulators. The Co and Ni sulfide counterparts are metallic for any inversion degree together with the inverse FeMn2S4. Our calculations suggest that the spin filtering properties of the FeM2X4 (thio)spinels could be modified via the control of the cation distribution through variations in the synthesis conditions

Measurement of K-S(0) and K*(0) in p plus p, d plus Au, and Cu plus Cu collisions at root s(NN)=200 GeV

The PHENIX experiment at the Relativistic Heavy Ion Collider has performed a systematic study of K-S(0) and K*(0) meson production at midrapidity in p + p, d + Au, and Cu + Cu collisions at root s(NN) = 200 GeV. The K-S(0) and K*(0) mesons are reconstructed via their K-S(0) -\u3e pi(0)(-\u3e gamma gamma) pi(0)(-\u3e gamma gamma) and K*(0) -\u3e K-+/-pi(-/+) decay modes, respectively. The measured transverse-momentum spectra are used to determine the nuclear modification factor of K-S(0) and K*(0) mesons in d + Au and Cu + Cu collisions at different centralities. In the d + Au collisions, the nuclear modification factor of K-S(0) and K*(0) mesons is almost constant as a function of transverse momentum and is consistent with unity, showing that cold-nuclear-matter effects do not play a significant role in the measured kinematic range. In Cu + Cu collisions, within the uncertainties no nuclear modification is registered in peripheral collisions. In central collisions, both mesons show suppression relative to the expectations from the p + p yield scaled by the number of binary nucleon-nucleon collisions in the Cu + Cu system. In the p(T) range 2-5 GeV/c, the strange mesons (K-S(0), K*(0)) similarly to the phi meson with hidden strangeness, show an intermediate suppression between the more suppressed light quark mesons (pi(0)) and the nonsuppressed baryons (p, (p) over bar). At higher transverse momentum, p(T) \u3e 5 GeV/c, production of all particles is similarly suppressed by a factor of approximate to 2

Scaling properties of fractional momentum loss of high-p(T) hadrons in nucleus-nucleus collisions at root s(NN) from 62.4 GeV to 2.76 TeV

Measurements of the fractional momentum loss (S-loss = delta p(T) / p(T)) of high-transverse-momentum-identified hadrons in heavy-ion collisions are presented. Using pi(0) in Au + Au and Cu + Cu collisions at root s(NN) = 62.4 and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb + Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of S-loss as a function of a number of variables: the number of participants, N-part, the number of quark participants, N-qp, the charged-particle density, dN(ch)/d(eta), and the Bjorken energy density times the equilibration time, epsilon(Bj)tau(0). We find that the p(T), where S-loss has its maximum, varies both with centrality and collision energy. Above the maximum, S-loss tends to follow a power-law function with all four scaling variables. The data at root s(NN) = 200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of S-loss with dN(ch)/d(eta) and epsilon(Bj)tau(0), lending insight into the physics of parton energy loss

Transverse energy production and charged-particle multiplicity at midrapidity in various systems from root s(NN)=7.7 to 200 GeV

Measurements of midrapidity charged-particle multiplicity distributions, dN(ch)/d eta, and midrapidity transverse-energy distributions, dE(T)/d eta, are presented for a variety of collision systems and energies. Included are distributions for Au + Au collisions at root s(NN) = 200, 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu + Cu collisions at root s(NN) = 200 and 62.4 GeV, Cu + Au collisions at root s(NN) = 200 GeV, U + U collisions at root s(NN) = 193 GeV, d + Au collisions at root s(NN) = 200 GeV, He-3 + Au collisions at root s(NN) = 200 GeV, and p + p collisions at root s(NN) = 200 GeV. Centrality-dependent distributions at midrapidity are presented in terms of the number of nucleon participants, N-part, and the number of constituent quark participants, N-qp. For all A + A collisions down to root s(NN) = 7.7 GeV, it is observed that the midrapidity data are better described by scaling with N-qp than scaling with N-part. Also presented are estimates of the Bjorken energy density, epsilon(BJ), and the ratio of dE(T)/d eta to dN(ch)/d eta, the latter of which is seen to be constant as a function of centrality for all systems

Beam-energy and centrality dependence of direct-photon emission from ultra-relativistic heavy-ion collisions

The PHENIX collaboration presents first measurements of low-momentum (0.41\,GeV/c) direct-photon yield dNdirγ/dη is a smooth function of dNch/dη and can be well described as proportional to (dNch/dη)α with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different, A+A collision systems. At a given beam energy the scaling also holds for high pT (\u3e5\,GeV/c) but when results from different collision energies are compared, an additional sNN−−−√-dependent multiplicative factor is needed to describe the integrated-direct-photon yield