Evaluation of fungicides for the management of Botryosphaeria dieback diseases of grapevines

BACKGROUND: A range of botryosphaeriaceous species can cause dieback and cankers in grapevines; however, different species most commonly affect the grapevines in different grape‐growing regions and countries. They infect through wounds and sporulate on woody stems and green shoots throughout the year, so wound protection is the recommended control strategy. This research evaluated fungicides for their ability to reduce mycelial growth and conidial germination of three botryosphaeriaceous species and to protect pruning wounds against infection. RESULTS: In vitro experiments showed that nine out of 16 tested fungicides were effective at reducing mycelial growth and/or conidial germination of three isolates each of Neofusicoccum australe, N. luteum and Diplodia mutila. The species differed in their response to the fungicides, although N. luteum was usually the least sensitive. When nine selected fungicides were sprayed on cane pruning wounds on potted and field grapevines and subsequently inoculated with N. luteum conidia, some effectively protected them from infection. The most effective fungicides were flusilazole, carbendazim, tebuconazole, thiophanate‐methyl and mancozeb, as they prevented the inoculated pathogen from infecting healthy wood in 100, 93, 87, 83 and 80% of field vines, respectively. CONCLUSION: This research has demonstrated that fungicides applied after winter pruning can protect vines from infection by conidia of three botryosphaeriaceous species. Copyright © 2012 Society of Chemical Industry     

加纳农业机械化发展潜力及制约因素（摘选）

作为政府职能的一部分实现联合国千年计划,即到2015年消除饥饿和极度贫困,为了实现经济可持续增长就需要现代化的农业。就这个问题而言,基于食品安全的必要性,在撒哈拉以南的非洲地区和加纳,发展的重点正逐步转向农业机械化。如果没有行之有效的农业机械化,加纳的食品和农业部门将无法达到预期的经济影响。该文旨在归纳农业机械化的制约因素,提出适合加纳的有效的机械化途径。主要制约机械化的因素包括缺乏熟练的农机操作人员,农场规模小,不适当的政府政策和农机成本高。在认识到机械化对于国家农业发展中的巨大作用后,就需要制定适合的土地所有制政策框架,鼓励联合经营和定制雇佣机械,向农民传授有关投资知识,鼓励标准服务投入。      

Seasonal variation in Campylobacter-contaminated retail chicken products: a year-round investigation in Japan

Campylobacter was isolated from retail meat samples collected during the fiscal year 2009 in Japan. The higher percentages of contamination of chicken products were observed from June (39.3%) to November (83.3%). However, the highest number of human campylobacteriosis cases was reported in June in the Infectious Agents Surveillance Report. The chicken isolates with distinct clusters IVb and I, based on the restriction fragment length polymorphism of the flaA gene, were predominantly obtained during the periods between April and November 2009 and between February and March 2010, respectively. Extensive monitoring of Campylobacter contamination in chickens produced in various places is needed to analyse the seasonal variations between contamination of the meat products and the number of human cases with campylobacteriosis.     

Growth response and sapwood hydraulic properties of young lodgepole pine following repeated fertilization

We examined how tree growth and hydraulic properties of branches and boles are influenced by periodic (about 6 years) and annual fertilization in two juvenile lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) stands in the interior of British Columbia, Canada. Mean basal area (BA), diameter at breast height (DBH) and height increments and percent earlywood and sapwood hydraulic parameters of branches and boles were measured 7 or 8 years after the initial treatments at Sheridan Creek and Kenneth Creek. At Sheridan Creek, fertilization significantly increased BA and DBH increments, but had no effect on height increment. At Kenneth Creek, fertilization increased BA, but fertilized trees had significantly lower height increments than control trees. Sapwood permeability was greater in lower branches of repeatedly fertilized trees than in those of control trees. Sapwood permeabilities of the lower branches of trees in the control, periodic and annual treatments were 0.24 x 10(-12), 0.35 x 10(-12) and 0.45 x 10(-12) m2 at Kenneth Creek; and 0.41 x 10(-12), 0.54 x 10(-12) and 0.65 x 10(-12) m2 at Sheridan Creek, respectively. Annual fertilization tended to increase leaf specific conductivities and Huber values of the lower branches of trees at both study sites. We conclude that, in trees fertilized annually, the higher flow capacity of lower branches may reduce the availability of water to support annual growth of the leader and upper branches.     

Carbon isotopes of water‐extractable organic carbon in a depth profile of forest soil imply a dynamic relationship with soil carbon

Although considerable research has been conducted on the importance of recent litter compared with older soil organic matter as sources of dissolved organic carbon (DOC) in forest soils, a more thorough evaluation of this mechanism is necessary. We studied water‐extractable organic carbon (WEOC) in a soil profile under a cool‐temperate beech forest by analysing the isotopic composition (¹³C and ¹⁴C) of WEOC and its fractions after separation on a DAX‐8 resin. With depth, WEOC became more enriched in ¹³C, which reflects the increasing proportion of the hydrophilic, isotopically heavier fraction. The ¹⁴C content in WEOC and its fractions decreased with depth, paralleling the ¹⁴C trend in soil organic matter (SOM). These results indicate a dynamic equilibrium of WEOC and soil organic carbon. The dominant process maintaining the WEOC pool in the mineral soil appears to be the microbial release of water‐soluble compounds from the SOM, which alters in time‐scales of decades to centuries.     

Physical and Molecular Characterization of Millet Starches

This study investigated the physical and molecular starch characteristics of four Canadian‐grown millet species: pearl, foxtail, proso, and finger millet. The millet starch granules ranged from about 2.5 to 24 μm in size and were mainly polygonal with a few spherical ones. Their amylose contents ranged from 28.6 to 33.9%, with finger and pearl millets having much more of long amylose chains than short amylose chains compared with foxtail and proso millets. Starches also differed in the molecular structure of their branched amylose, with finger and pearl millets having longer glucan chains between branch points. The enthalpy of gelatinization of starch granules ranged from 11.8 to 13.2 J/g, and the enthalpy of melting of the retrograded starches ranged from 2.2 to 5.9 J/g. The onset temperature of gelatinization (T_o) of the starches ranged from 62.8 to 70.6°C. Addition of iodine vapor to the granular starches showed significant (P < 0.05) differences in the ratio of the absorbance to scattering coefficient (K/S) values, indicating differences in the rigidity of the glucan chains present in the granules. Starches with short amylose chains exhibited higher K/S values. Iodine vapor addition resulted in altered X‐ray diffractogram peak intensities. The study suggested differences in the structure and granular architecture of the millet starches.     

Butremycin,the 3-Hydroxyl Derivative of Ikarugamycin and a Protonated Aromatic Tautomer of 5′-Methylthioinosine from a Ghanaian Micromonospora sp. K310

A new actinomycete strain Micromonospora sp. K310 was isolated from Ghanaian mangrove river sediment. Spectroscopy-guided fractionation led to the isolation of two new compounds from the fermentation culture. One of the compounds is butremycin (2) which is the (3-hydroxyl) derivative of the known Streptomyces metabolite ikarugamycin (1) and the other compound is a protonated aromatic tautomer of 5′-methylthioinosine (MTI) (3). Both new compounds were characterized by 1D, 2D NMR and MS data. Butremycin (2) displayed weak antibacterial activity against Gram-positive S. aureus ATCC 25923, the Gram-negative E. coli ATCC 25922 and a panel of clinical isolates of methicillin-resistant S. aureus (MRSA) strains while 3 did not show any antibacterial activity against these microbes.     

Butrepyrazinone,a New Pyrazinone with an Unusual Methylation Pattern from a Ghanaian Verrucosispora sp. K51G

We report the structural characterization of a new pyrazinone analogue; butrepyrazinone, which was isolated from a new actinomycete strain Verrucosispora sp. K51G recovered from Ghanaian mangrove river sediment. Spectroscopy-guided fractionation led to the isolation of a compound from the fermentation culture and a combination of NMR spectroscopy, high-resolution mass spectrometry and computer-aided calculations revealed that butrepyrazinone (10) possesses an unusual methylation pattern on the pyrazinone ring. Butrepyrazinone (10), however, displayed no antibacterial activity against Gram-positive S. aureus ATCC 25923, the Gram-negative E. coli ATCC 25922 and a panel of clinical isolates of methicillin-resistant S. aureus (MRSA) strains, suggesting that 10 may act as a signal molecule for this strain. Although the same molecule has been synthesized previously, this is the first report to disclose the discovery of butrepyrazinone (10) from nature.     

Evaluation of the antioxidant activity of environmental plants: activity of the leaf extracts from seashore plants

The antioxidant activity of the methanolic extracts of the leaves of 39 plant species was examined. These leaves were collected from the plants growing on subtropical seashores. The activity was evaluated by three kinds of assay methods, which included the DPPH radical scavenging assay, linoleic acid oxidation assay, and oxidative cell death assay. Two extracts from Excoecaria agallocha and Terminalia catappa showed remarkably potent activity in all assay systems. The HPLC analysis of the extracts indicated the presence of the same antioxidant and isolation work for the compound identified ellagic acid. The isolated ellagic acid showed strong antioxidant activity in the assay systems used.