Optimization and Application of a Quantitative Polymerase Chain Reaction Assay to Detect Diaporthe Species in Soybean Plant Tissue

Diaporthe caulivora and D. longicolla are the causal agents of stem canker of soybean (Glycine max L.). Accurate identification of stem canker pathogens upon isolation from infected soybean plants is difficult and unreliable based on morphology. In this study, two TaqMan probe-based quantitative polymerase chain reaction (qPCR) assays were optimized for detection of D. caulivora and D. longicolla in soybean plants. The assays used previously reported D. caulivora-specific (DPC-3) and D. longicolla-specific (PL-3) probe/primer sets. The sensitivity limit of the two assays was determined to be over a range of 100 pg to 10 fg of pure D. caulivora and D. longicolla genomic DNA. The qPCR assays were validated with plant samples collected from commercial soybean fields. The PL-3 set detected D. longicolla in soybean plants collected from the fields (quantification cycle value \u3c35), which was confirmed by isolation on potato dextrose agar (PDA). D. caulivora was detected only in low levels (quantification cycle value \u3c40) by DPC-3 set in a few of the symptomatic field samples, although the pathogen was not isolated on PDA. The qPCR assays were also useful in quantitatively phenotyping soybean plants for resistance to D. caulivora and D. longicolla under greenhouse conditions

Laser control in a bifurcating region

We present a complete analysis of the laser control of a model molecular system using both optimal control theory and adiabatic techniques. This molecule has a particular potential energy surface with a bifurcating region connecting three potential wells which allows a variety of processes such as isomerization, tunneling, or implementation of quantum gates on one or two qubits. The parameters of the model have been chosen so as to reproduce the main features of H3CO which is a molecule benchmark for such dynamics. We show the feasibility of different processes and we investigate their robustness against variations of laser field. We discuss the conditions under which each method of control gives the best results. We also point out the relation between optimal control theory and local control

Eight Species of Fusarium Cause Root Rot of Corn (Zea mays) in South Dakota

Fusarium root rot of corn (Zea mays L.) is yield-limiting in the United States, but there is no information available on the disease in South Dakota. In 2015, corn seedlings with discolored roots were arbitrarily sampled from 50 South Dakota fields, and 198 isolates were recovered. Eight species (F. acuminatum, F. boothii, F. equiseti-incarnatum complex, F. graminearum, F. oxysporum, F. proliferatum, F. solani, and F. subglutinans) were identified by morphology and translation elongation factor 1-α gene sequencing. F. graminearum (26.8%) was the most common fungus, and F. boothii (0.5%) was the least recovered. Fourteen isolates, representing the eight species, were evaluated for their pathogenicity on 2-week-old seedlings of inbred ‘B73’ using the inoculum layer method in the greenhouse. Fourteen days postinoculation, root rot severity was evaluated on a 1-to-5 rating scale and expressed as relative treatment effects (RTEs). F. proliferatum isolate P2 caused significantly greater RTE (based on 95% confidence intervals) on seedlings than the other isolates and the noninoculated control, except F. graminearum isolate FG23. This study indicates that the eight species of Fusarium are aggressive root rot pathogens of corn in South Dakota, and this information will help evaluate strategies for producers to manage these pathogens in their fields

A design of and design tools for a novel quantum dot based microprocessor

Despite the seemingly endless upwards spiral of modern VLSI technology, many experts are predicting a hard wall for CMOS in about a decade. Given this, researchers continue to look at alternative technologies, one of which is based on quantum dots, called quantum cellular automata (QCA). While the first such devices have been fabricated, little is known about how to design complete systems of them. This paper summarizes one of the first such studies, namely an attempt to design a complete, albeit simple, CPU in the technology. To design a theoretical QCA microprocessor, two things must be accomplished. First a device model of the processor must be constructed (i.e. the schematic itself). Second, methods for simulating and testing QCA designs must be developed. This paper summarizes the beginnings of a simple QCA microprocessor (namely, its dataflow) and a QCA design and simulation tool

First Report of Diaporthe gulyae Causing Phomopsis Stem Canker of Sunflower (Helianthus annuus) in Argentina

Between 2014 and 2017, elongated, brown lesions were observed on the stem and heads of sunflower (Helianthus annuus L.) plants in the Argentine Southern Sunflower Region (ASSR). A total of 66 diseased plants (40 stems and 26 heads) were sampled from the three production fields: Balcarce (37°52′36.6″S; 58°15′29.4″W; 19 samples), Orense (38°41′36.3″S; 59°47′01.9″W; 36 samples), and Pieres (38°23′31.2″S; 58°40′22.8″W; 11 samples). Fungal isolations were made from the lesion margins of the stem and head by cutting, surface disinfesting, and plating tissue pieces on potato dextrose agar (PDA) amended with 0.02% lactic acid (pH 4.5). The PDA plates were incubated at 25°C for 7 to 10 days under a 12-h photoperiod, and hyphal tips of white to gray colonies were transferred to fresh PDA plates

IMPEDANCE SHAPING FOR IMPROVED FEEL IN HYDRAULIC SYSTEMS

ABSTRACT Applying haptic control to mobile hydraulic equipment presents a practical yet challenging application. One criticism of newer electro-hydraulic system is a lack of "feel." To a haptics researcher this sounds like a call for haptic feedback in the human-machine interface. However, for an operator the "feel" of the system likely has more to do with how the actual system responds to forces or higher work port pressures. At some point, the high pressures slow down the system or naturally redirect flow to lower pressure circuits in a hydro-mechanical system. How this is done plays a large part in the "feel" of the system. In this paper, a paradigm is presented that tries to merge these two concepts of "feel." Instead of trying to make the system transparent, the goal is to make the system react to forces acting on the system then use haptic feedback to help alert the operator to these forces. This is done by shaping this impedance so that the system provides a response or "feel" that is closer to a typical excavator. A haptic interface is used to enhance the haptic feel. Performance is evaluated using data from human-in-the-loop testing INTRODUCTION The definition of haptics is of or relating to the sense of touch. Haptic control implies that the human-machine interface can be programmed to artificially supply the user with arbitrary force sensations. Typically the haptic force is used to relay information about the force acting on a remote or virtual environment. Haptic feedback means that information can be fed back to the operator in the form of force signals. In the case of backhoes/excavators, force signals can be generated by virtual fixtures Haptic devices can also enable coordinated motion control. Today almost all commercial backhoes/excavators are controlled by joystick commands from human operators that are mapped directly into the joint-space of the manipulator. Coordinated control is a subtle yet profound improvement over conventional hand controllers that work in joint space. Using joysticks that individ

Characterization of species of Fusarium causing root rot of Soybean (Glycine max L.) in South Dakota, USA

In 2014, 2000 plants showing root rot symptoms were collected from 200 commercial soybean (Glycine max L.) fields in South Dakota, USA. One thousand one hundred thirty fungal isolates obtained from the samples were identified as Fusarium species by morphology and sequencing of the translation elongation factor 1-alpha gene. Fifty-one percent were F. graminearum, 30.0% were F. acuminatum, 8.0% belonged to the F. oxysporum species complex, 3.4% were F. armeniacum, 2.0% were F. proliferatum, 1.6% were F. virguliforme, 1.2% belonged to the F. solani species complex, 0.4% were F. nanum (syn. F. incarnatum-equiseti species complex), 0.1% were F. bulbicola (syn. F. fujikuroi species complex) and 0.1% were F. commune. The pathogenicity of 57 isolates was evaluated on the soybean 'Asgrow 1835' under greenhouse conditions. Root rot severity was rated 14 days after inoculation on a 1-to-5 scale and expressed as relative treatment effects (RTE). Nine isolates of F. oxysporum, and one each of F. armeniacum and F. commune, caused significantly greater RTE than in the non-inoculated control. Twenty-one accessions were screened for resistance in the greenhouse using one isolate each of F. graminearum, F. proliferatum and F. sporotrichioides. Accession PI361090 was less susceptible to F. graminearum and F. proliferatum than the susceptible controls, 'Williams 82' and 'Asgrow 1835'. All accessions were more susceptible to F. sporotrichioides. These findings suggest that 11 Fusarium species or species complexes are pathogenic to soybean in South Dakota, and PI361090 may be a useful source of resistance to F. graminearum and F. proliferatum

Six species of Diaporthe associated with Phomopsis stem canker of sunflower in southern Pampean region of Argentina

A survey of 67 commercial fields in 19 locations was conducted in the southern Pampean region of Argentina for Phomopsis stem canker of sunflower (Helianthus annuus L.) between 2014 and 2019. A total of 210 plants having typical symptoms of Phomopsis stem canker were randomly sampled, and fungal isolation was performed. Of the 187 isolates of Diaporthe that were recovered, 94% of the isolates showed morphological characteristics similar to D. helianthi, 3% to D. gulyae, 1% to D. caulivora, 1% to D. sojae, 0.5% to D. kongii, and 0.5% to D. longicolla. Following morphological characterization, the identity of the six morpho-species was confirmed by phylogenetic analyses of b-tubulin, translation elongation factor 1-a, and internal transcribed spacer gene regions. Koch’s postulates were completed for the six fungi by inoculating one susceptible sunflower hybrid with one isolate each of the six species of Diaporthe using the stem-wound inoculation method. Seven days postinoculation, significant differences in disease severity were observed between the six isolates (P < 0.0001), with D. helianthi and D. gulyae isolates causing significantly greater disease severity. To our knowledge, this is the first report of D. kongii, D. longicolla, D. caulivora, and D. sojae associated with Phomopsis stem canker of sunflower in Argentina.Fil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Mancebo, María F.. Advanta Semillas S.A.I.C.; ArgentinaFil: Bazzalo, María E.. Advanta Semillas S.A.I.C.; ArgentinaFil: Reid, Roberto J.. Advanta Semillas S.A.I.C.; ArgentinaFil: Sanchez, María C.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Kontz, Brian J.. South Dakota State University; Estados UnidosFil: Mathew, Febina M.. South Dakota State University; Estados Unido