893 research outputs found

    The role of variation in genetic susceptibility to soybean rust on the photosynthetic competence of infected leaves.

    Get PDF
    Three soybean rust infection types have been reported: 1) tan lesions indicate a compatible and susceptible reaction, 2) red- brown (RB) lesion type has been associated with few non-sporulating uredinia representing a resistant reaction, and 3) immune reaction with no visible evidence of infection. Differences among cultivars would imply genotypic differences in tolerance, which can be define as the ability of the host to endure the presence of the pathogen with reduced disease symptoms and/or damages. Soybean rust-induced yield loss has been associated with reduction in light interception due to premature leaf loss and the lesions on the remaining green leaves. Incorporation of the effect of the pathogen on photosynthetic efficiency of disease leaves from different soybean cultivars in model to predict production might increase the accuracy and precision of the estimates supply by this model. Bastiaans (1991) proposed the concept of a "virtual lesion" and developed a simple model Y= (1-x)? to fit empirical data and describe the relationship between the reduction in relative photosynthesis in a diseased leaf (Y), and the disease severity (x). The value of â indicates whether the effect of disease on photosynthesis is higher (? > 1), lower (? < l) or equal (? = 1) to that accounted for by the observed diseased area. Reliable estimate of disease effects on growth and yield depends on the ability to accurate quantify the parameter ?. The objective of the current study was to determine the role of host-plant variation in disease susceptibility on soybean leaf gas exchange in field and control environment studies. The specific objectives are to quantify the ? value for SBR-infected leaves as influenced by plant growing conditions and genetic variation in disease susceptibility.Edição do Proceedings of the National Soybean Rust Symposium, New Orleans, 2009

    Proceedings of the 17th Annual Meeting, Southern Soybean Disease Workers (March 20-22, 1990, Biloxi, Mississippi): Soybean Disease Control at a Crossroad

    Get PDF
    Contents Southern Soybean Disease Workers Officers 1989-1990 Southern Soybean Disease Workers Program Committee 1989-1990 Southern Soybean Disease Workers Committee Chairmen 1989-1990 General session Presidential address. B Gazaway Keynote address. K Smith Invited speakers Future Impacts of Biotechnology on Soybean Production and Uses. X Delannay Diseases of Soybean Associated with International Seed Trade. B Moore Impact of Regulatory Change and GLP\u27s on New Fungicide Discovery and Development. G Hammes Graduate student papers Double-Stranded RNA and Virus-Like Particles From the Soybean Stem canker Pathogen, Diaporthe phaseolorum var. caulivora. Y Lee, JP Snow, GT Berggren, and RA Valverde Development of Soybean Varieties Resistant to Phomopsis Seed Decay. MS Zimmerman and HC Minor Cloning of the vir Region of Agrobacterium tumefaciens Chry 5, a Strain Highly Virulent on Soybean. LG Kovacs, JA Wrather, and SG Pueppke Role of Overwintering Bean Leaf Beetle in the Epidemiology of Bean Pod Mottle Virus in Soybeans in Kentucky. JR dosAnjos, SA Ghabinal, DE Hershman, and DW Johnson Contributed papers SSDW soybean Disease Loss Estimates G Sciumbato Effects of Amino Acid Biosynthesis Inhibiting Herbicides on in vitro Growth and Development of Calonectria crotalariae. DK Berner, GT Berggren, and JP Snow Infection Cushion Formation by Rhizoctonia solani on Soybean Leaves. CS Kousik, JP Snow, and GT Berggren Is Stem Canker Monocyclic? KV SubbaRao, JP Snow, and GT Berggren Early-season Fungicide Sprays for Soybean Stem Canker Control. AY Chambers SSDW business session Treasurer\u27s report, 1989. G Hammes Contributed paper session Effect of Frogeye Leaf Spot on Soybeans in Florida. FM Shakes and CK Hiebsch Comparison of Application Timing of Two Foliar Fungicides for Control of Soybean Diseases. JC Rupe and MJ Cochran Performance of Soybean Lines under Stress Due to Brown Stem Rot, Soybean Cyst Nematode, and Iron Deficiency Chlorosis. LM Mansur, H Tachibana, and K Bidne Performance of Soybean Cultivars in Cyst and Peanut Root-Knot Nematode Infested Fields. CE Drye, DK Barefield, ER Shipe, and JD Mueller Yield of Aldicarb Treated Nematode Resistant and Susceptible Soybean Varieties. CE Drye, ER Garner, and JD Mueller Distribution, Races, and Effects of Soybean Cyst Nematode in Missouri. TL Niblack and GS Smith Performance of Selected Nematicides in a Field Infested with Root-Knot and Cyst Nematodes. RW Young, R Rodríguez-Kábana, and EL Carden Performance of Selected Soybean Cultivars in a Field Infested with Meloidogyne arenaria and Heterodera glycines. DG Robertson, R Rodríguez-Kábana, D Weaver, and EL Carden Sorghum-Soybean Rotation for the Management of Root-Knot and Cyst Nematodes: Long Term Effects. CF Weaver, R Rodríguez-Kábana, DB Weaver, and EL Carden Bahiagrass-Soybean Rotation for the Management of Root-Knot and Cyst Nematodes: Long Term Effects. PS King, R Rodríguez-Kábana, DB Weaver, and EL Carden Peanut-Soybean Rotations for the Management of Meloidogyne arenaria. R Rodríguez-Kábana, and DG Robertson Field Evaluation of Polyspecific Nematode Resistance in Soybean. DB Weaver, R Rodríguez-Kábana, and EL Carden Long Term Effects of Selected Rotations with Soybeans and Corn on Populations of Meloidogyne arenaria. R Rodríguez-Kábana, and D.G. Robertson Histopathology of Soybean Roots Inoculated with Fusariurn solani and Heterodera glycines. KS McLean, KW Roy and GW Lawrence. The opinions expressed by the participants at this conference are their own and do not necessarily represent the views of the southern Soybean Disease Workers (SSDW). Text, references, figures, and tables are reproduced essentially as they were supplied by the author(s) of each paper. Mention of pesticides does not constitute a recommendation for use, nor does it imply that the pesticides are registered under the Federal Insecticide, Fungicide, and Rodenticide Act as · amended. The use of trade names in this publication does not constitute a guarantee, warranty, or endorsement of the products by SSDW

    Association of Meniscal Status, Lower Extremity Alignment, and Body Mass Index With Chondrosis at Revision Anterior Cruciate Ligament Reconstruction

    Get PDF
    BACKGROUND: Knees undergoing revision anterior cruciate ligament reconstruction (rACLR) have a high prevalence of articular cartilage lesions. HYPOTHESIS: The prevalence of chondrosis at the time of rACLR is associated with meniscal status and lower extremity alignment. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Data from the prospective Multicenter ACL Revision Study (MARS) cohort were reviewed to identify patients with preoperative lower extremity alignment films. Lower extremity alignment was defined by the weightbearing line (WBL) as a percentage of the tibial plateau width, while the chondral and meniscal status of each weightbearing compartment was recorded at the time of surgery. Multivariable proportional odds models were constructed and adjusted for relevant factors to examine which risk factors were independently associated with the degree of medial and lateral compartment chondrosis. RESULTS: The cohort included 246 patients with lower extremity alignment films at the time of rACLR. Mean (+/-SD) patient age was 26.9 +/- 9.5 years and body mass index (BMI) was 26.4 +/- 4.6. The medial compartment had more chondrosis (grade 2/3, 42%; grade 4, 6.5%) than did the lateral compartment (grade 2/3, 26%; grade 4, 6.5%). Disruption of the meniscus was noted in 35% of patients on the medial side and 16% in the lateral side. The mean WBL was 0.43 +/- 0.13. Medial compartment chondrosis was associated with BMI (P = .025), alignment (P = .002), and medial meniscal status (P = .001). None of the knees with the WBL lateral to 0.625 had grade 4 chondrosis in the medial compartment. Lateral compartment chondrosis was significantly associated with age (P = .013) and lateral meniscal status (P \u3c .001). Subjects with intact menisci were found to decrease their odds of having chondrosis by 64% to 84%. CONCLUSION: The status of articular cartilage in the tibiofemoral compartments at the time of rACLR is related to meniscal status. Lower extremity alignment and BMI are associated with medial compartment chondrosis

    A low pH enzyme linked immunoassay using two monoclonal antibodies for the serological detection and monitoring of breast cancer.

    Get PDF
    A new, simple and sensitive low pH ELISA method has been developed to measure serum levels of tumour associated antigens detectable by monoclonal antibodies HMFG1 and HMFG2. We examined sera from healthy controls, patients with neoplastic and non-neoplastic conditions of breast, liver and gastrointestinal tract. The majority of patients with metastatic breast cancer had elevated serum antigens (69% HMFG1, 72% HMFG2) compared to healthy controls (6.3% HMFG1, 3.0% HMFG2) or patients with benign breast disease (17% HMFG1, 4% HMFG2). There was no discrimination using these assays between patients with neoplastic and non-neoplastic conditions of liver and gastrointestinal tract. This new method promises to be of value in the assessment and management of patients with breast cancer

    Quantum key distribution with 1.25 Gbps clock synchronization

    Full text link
    We have demonstrated the exchange of sifted quantum cryptographic key over a 730 meter free-space link at rates of up to 1.0 Mbps, two orders of magnitude faster than previously reported results. A classical channel at 1550 nm operates in parallel with a quantum channel at 845 nm. Clock recovery techniques on the classical channel at 1.25 Gbps enable quantum transmission at up to the clock rate. System performance is currently limited by the timing resolution of our silicon avalanche photodiode detectors. With improved detector resolution, our technique will yield another order of magnitude increase in performance, with existing technology.Comment: 6 pages, 3 figures, 99 kB .pdf documen
    corecore