Cross-resistance profile of mesosulfuron-methyl-resistant Italian ryegrass in the southern United States

Diclofop-resistant Lolium species (ryegrass) is a major weed problem in wheat production worldwide. This study was conducted to determine the resistance pattern of diclofop-resistant ryegrass accessions from the southern United States to mesosulfuron-methyl, a recently commercialized herbicide for ryegrass control in wheat; to determine the cross-resistance pattern of a Lolium multiflorum Lam. (Italian ryegrass) accession, 03-1, to acetolactate synthase (ALS) and acetyl-CoA carboxylase (ACCase) inhibitors; and to determine the resistance mechanism of Italian ryegrass to mesosulfuron-methyl. Seventeen ryegrass accessions from Arkansas and Louisiana, including standard resistant and susceptible accessions, were used in this experiment. Fourteen of the 17 accessions were more resistant (four- to > 308-fold) to diclofop than the standard susceptible biotype. One accession, 03-1, was resistant to mesosulfuron-methyl as well as to other ALS inhibitor herbicides such as chlorsulfuron, imazamox and sulfometuron. Accession 03-1, however, did not show multiple resistance to the ACCase inhibitor herbicides diclofop, fluazifop, clethodim, sethoxydim and pinoxaden, nor to glyphosate. The in vivo ALS activity of the 03-1 biotype was less affected by mesosulfuron-methyl than the susceptible biotype. This indicates that the resistance mechanism of Italian ryegrass to mesosulfuron-methyl is partly due to an alteration in the target enzyme, ALS. It is concluded that diclofop-resistant ryegrass in the southern United States can be generally controlled by mesosulfuron-methyl. However, mesosulfuron-methyl must be used with caution because not all ryegrass populations are susceptible to it. There is a need for more thorough profiling of ryegrass resistance to herbicides.     

Effects of different fractions of Rheum palmatum root extract and anthraquinone compounds on fungicidal,insecticidal, and herbicidal activities

Journal of Plant Diseases and Protection - This study was conducted to evaluate the suppression of Pyricularia oryzae, Colletotrichum coccodes, Rhizoctonia solani, Phytophthora capsici, and...     

TEMPO-mediated oxidation of MCC at high temperature: Synthesis and characterization of high-hydrophilic polymer

Microcrystalline cellulose was reacted with catalytic amounts of 2, 2, 6, 6-tetramethyl-1-piperidine oxoammonium salt (TEMPO), sodium hypochlorite and sodium bromide in Na₂CO₃/NaHCO₃ buffer solution at different temperatures (30 °C, 40 °C, 50 °C). The oxidation procedures included first oxidation and second oxidation. The yield of cellouronic acid produced in the second oxidation was higher than the yield of cellouronic acid produced in the first oxidation at the same oxidation temperature. Moreover, an interesting “high-hydrophilic” phenomenon appeared at higher temperature during microcrystalline cellulose second oxidation (30 °C, 40 °C, 50 °C). Properties associated with the chemical characteristics are discussed by XRD, FTIR, ¹³C-NMR and Laser Particle Analyzer in view of its interesting high-hydrophilic effects.     

The effect of ornithine and citrulline on tile utilization of arginine in rice callus tissue

There are many reports on the effect of arginine on the growth of cultivated tissues or organs. Arginine usually enhances the growth of tissues and organs (1-9).     

Dieckol Decreases Caloric Intake and Attenuates Nonalcoholic Fatty Liver Disease and Hepatic Lymphatic Vessel Dysfunction in High-Fat-Diet-Fed Mice

Increased inflammation is the main pathophysiology of nonalcoholic fatty liver disease (NAFLD). Inflammation affects lymphatic vessel function that contributes to the removal of immune cells or macromolecules. Dysfunctional lymphatic vessels with decreased permeability are present in NAFLD. High-fat diet (HFD) is known to increase body weight, food intake, and inflammation in the liver. Previously, it was reported that Ecklonia cava extracts (ECE) decreased food intake or weight gain, and low-calorie diet and weight loss is known as a treatment for NAFLD. In this study, the effects of ECE and dieckol (DK)—which is one component of ECE that decreases inflammation and increases lymphangiogenesis and lymphatic drainage by controlling lymphatic permeability in high-fat diet (HFD)-fed mice—on weight gain and food intake were investigated. ECE and DK decreased weight gain and food intake in the HFD-fed mice. NAFLD activities such as steatosis, lobular inflammation, and ballooning were increased by HFD and attenuated by ECE and DK. The expression of inflammatory cytokines such as IL-6 and TNF-α and infiltration of M1 macrophages were increased by HFD, and they were decreased by ECE or DK. The signaling pathways of lymphangiogenesis, VEGFR-3, PI3K/pAKT, and pERK were decreased by HFD, and they were restored by either ECE or DK. The expression of VE-cadherin (which represents lymphatic junctional function) was increased by HFD, although it was restored by either ECE or DK. In conclusion, ECE and DK attenuated NAFLD by decreasing weight gain and food intake, decreasing inflammation, and increasing lymphangiogenesis, as well as modulating lymphatic vessel permeability.     

Differential tolerance of weedy red rice (Oryza sativa L.) from Arkansas, USA to glyphosate

Red rice (Oryza sativa L.), a weedy relative of cultivated rice (O. sativa), is a troublesome weed in rice in the southern United States. It is also very problematic in other world regions where rice is grown. There are many types of red rice. Some have white pericarp. In this paper, the term ‘red rice’ will be used to refer to the weedy types that occur in this region of the southern USA. Because of the great diversity in morphology and phenology of red rice populations in the USA, we hypothesized that these have differential tolerance to glyphosate. Red rice is subjected to selection pressure by glyphosate, which is the principal herbicide used in glyphosate-resistant soybean planted after rice. Two hundred-fifteen red rice accessions were collected in Arkansas, USA between 2002 and 2003 and evaluated for glyphosate tolerance between 2003 and 2006. The commercial dose of glyphosate controlled red rice accessions 81-100% regardless of application timing, by 30 d after treatment. The number of survivors that produced seeds and the seeds produced per survivor differed between accessions. Application of the full dose at the tillering stage was more effective than at the 3- to 4-leaf stages. At half the field dose, 40 to 54% of survivors produced seed, with germination capacity of 30-100%. The lowest dose of glyphosate, 225 g a.e. ha⁻¹, resulted in the widest range of control ratings from 30 to 100%. The red rice accessions differentiated into six tolerance categories. A tolerance map was generated and will be used in educating growers about the proper use of glyphosate for red rice management.     

Heterosporis anguillarum infections in farm cultured eels (Anguilla japonica) in Korea

Ten eels (Anguilla japonica) from a fish farm in Korea were examined and diagnosed with a Heterosporis infection. The gross lesions on the trunk were uneven and the concave parts were pasty. Histopathologically, lyses of the trunk muscles, degenerative muscle fibers and the scattered spores were observed. The sporophorocyst (SPC) contained several spores with a variety of shapes. Some SPC were disrupted and the spores in the SPC were scattered in the muscle tissues. Macrophages existed near the scattered spores. Electron microscopy revealed special structures such as sporophorocyst containing various developmental parasitic stages such as meronts, sporonts, sporophorous vesicles and spores.     

Single nucleotide polymorphism discovery and linkage mapping of lipoxygenase-2 gene (Lx 2) in soybean

Lipoxygenase-2 (Lx ₂) in soybean seed is mainly responsible for generation of grassy-beany and bitter flavors. Genetic elimination of this flavor can be accelerated by the development of single nucleotide polymorphism (SNP) markers linked to Lx ₂. A frame map based on simple sequence repeat (SSR) markers was constructed first using a recombinant inbred line (RIL) population of Pureunkong × Jinpumkong 2. Sixty-five SSR markers were incorporated into 13 linkage groups (LGs) spanning a total of 737 cM. Among five primer pairs designed from the Lx ₂ gene sequence, one produced an amplicon with sequence variations between Pureunkong and Jinpumkong 2. Three SNPs, T/C, G/A and C/A, were identified at 251,367 and 420 bp, respectively, in the intron region of the 804 bp amplified product. Using single base chain extension based on the capture probe sequence in the 5' region of the T/C SNP, the 90 RILs were genotyped for each allele of Lx ₂. The allelic segregation for the SNP linked toLx ₂ was in accordance with the expected ratio of 1:1 in the RIL population. Based on the results of linkage analysis between Lx ₂ and the SSR markers, Lx ₂ was found to be positioned on one end of LG F in the frame map, flanked by the SSR markers Satt522 and Sat074. This study demonstrates that SNP markers closely linked to Lx ₂can be developed to facilitate marker-assisted selection and fine mapping of the region around this locus. This revised version was published online in July 2006 with corrections to the Cover Date.     

Reproduction of Mm.106 Rootstocks Propagated by Stooling as Affected by Organic Sources

Six organic sources of nutrients including commercial organic fertilizer (CF), poultry litter (PL), green compost (GC), wood chips (WC), shredded paper (SP), grass clippings (GR), and extracts from water (NF, as a control) were investigated under controlled conditions. One-year-old MM.106 apple (Malus × domestica Borkh.) trees grown under greenhouse conditions in 10 L pots were treated with nutrient solutions. All treatments were applied proportionally based on the volume ratio of material recommended for organic apple orchard field production. A nutrient solution from GC provided the greatest total nitrogen (N) input over the 12-week experimental period, followed in order by the GR, PL, WC, CF, SP, and NF treatments. The PL- and GR-treated plants had the largest stem diameter, largest leaf area, longest stem extension, and fastest dry matter production rate, as well as greater carbon dioxide (CO₂) assimilation, SPAD readings, N accumulation, and N use efficiency.     

Determination of staphylococcal exotoxins, SCCmec types, and genetic relatedness of Staphylococcus intermedius group isolates from veterinary staff, companion animals, and hospital environments in Korea

The Staphylococcus (S.) intermedius group (SIG) has been a main research subject in recent years. S. pseudintermedius causes pyoderma and otitis in companion animals as well as foodborne diseases. To prevent SIG-associated infection and disease outbreaks, identification of both staphylococcal exotoxins and staphylococcal cassette chromosome mec (SCCmec) types among SIG isolates may be helpful. In this study, it was found that a single isolate (one out of 178 SIG isolates examined) harbored the canine enterotoxin SEC gene. However, the S. intermedius exfoliative toxin gene was found in 166 SIG isolates although the S. aureus-derived exfoliative toxin genes, such as eta, etb and etd, were not detected. SCCmec typing resulted in classifying one isolate as SCCmec type IV, 41 isolates as type V (including three S. intermedius isolates), and 10 isolates as non-classifiable. Genetic relatedness of all S. pseudintermedius isolates recovered from veterinary staff, companion animals, and hospital environments was determined by pulsed-field gel electrophoresis. Strains having the same band patterns were detected in S. pseudintermedius isolates collected at 13 and 18 months, suggesting possible colonization and/or expansion of a specific S. pseudintermedius strain in a veterinary hospital.