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Sublethal and transgenerational effects of synthetic insecticides on the biological parameters and functional response of Coccinella septempunctata (Coleoptera: Coccinellidae) under laboratory conditions
No full textSynthetic insecticides have been an inevitable part of plant protection throughout the world. Sublethal effects of these chemicals on beneficial insect species are one of the contemporary issues these days. Using the age-stage, two-sex life table model, this study evaluated the sublethal and transgenerational effects of six synthetic insecticides (imidacloprid, thiamethoxam, lambda-cyhalothrin, cypermethrin, chlorpyrifos and profenofos) commonly applied to winter vegetables, on the fitness and predation of the seven-spotted ladybeetle, Coccinella septempunctata , which is an efficient predator of aphids worldwide. According to results, all insecticides at their sublethal doses (LC 30 ) significantly suppressed the emergence of adults, adult weight, fertility and fecundity of the parental generation compared to control treatment. The larval stage was prolonged and oviposition, fecundity and total longevity of the adult beetles were decreased in unexposed progeny whose parents were exposed to sublethal doses of all insecticides. Moreover, the biological parameters of adults, including the intrinsic rate of increase ( r ), finite rate of increase ( λ ) and net reproductive rate ( R 0 ) were significantly reduced when exposed to sublethal doses of insecticides. The predation rate of the F 1 generation adults was also decreased after exposure to the sublethal doses of insecticides. However, chlorpyrifos, profenofos, lambda-cyhalothrin and cypermethrin exhibited more deleterious effects on the fitness and population parameters of beetles than imidacloprid and thiamethoxam
Review of the effects of incising on treatability and strength of wood
No full textIn wood, longitudinal fluid flow is several orders of magnitude greater than in radial or tangential directions. Incising of difficult-to-treat (i.e. refractory) wood species is a critical step in achieving adequate preservative penetration. Incising, as broadly defined, involves creating holes, incisions or fluid pathways to varying depths into the timber to increase longitudinal fluid flow and penetration into the wood. Incising has been used globally with early development occurring in the U.S., Canada, U.K. and Germany. It has been most heavily adopted in North America where it is required for treatment of thin sapwood lumber species in both the Canadian and U.S. treatment and engineering design standards. Incising can be either physical or biological. Physical incising uses teeth, knives, drills, needles, lasers, or high-pressure water jets to create pathways in the wood to the depth of the desired preservative treatment in a pattern that ensures uniform treatment. Biological incising uses bacteria or fungi to increase permeability. This review outlines the development, processes, applications and effects of incising technology. It specifically discusses their effects on treatability and strength properties, and reviews recent developments for modeling incising-related strength effects
Why early season square retention rarely matters for high yielding Bollgard 3 In Australia
No full textIndustry data indicates cotton crops are commonly sprayed twice during squaring to regulate retention. For operational convenience insecticides are usually applied simultaneously with glyphosate for weed management. However, not only is the economic benefit of this practice unverified, additional insecticide both disrupts integrated pest management and contributes to the industry's environmental footprint. The impact of square loss in commercially grown high yielding Bollgard 3 fields was assessed from Emerald to Griffith over three consecu ve seasons. In each field three square removal treatments (from frui ng branches 1-5, 6-10 and 1-10) were replicated with an undamaged control, and growth and yield component responses were measured. For 33 out of 34 sites, total square removal from the first 5 fruiting branches prior to flowering had no impact on crop maturity, lint yield or quality. Compensation was rapid, occurring via additional bolls retained on sympodia immediately above or on distal fruiting positions adjacent to lost positions. Compensation was not reliant on additional mainstem node production, explaining the negligible impact on crop maturity. The data has been used to revise industry recommendations for early season fruit retention on that aim to balance the need to spray with the capacity of cotton to compensate square losses
Utilising the double knock to increase efficacy of weed control on major weeds in Xtendflex co on systems.
No full textCotton with resistance to dicamba and glufosinate and glyphosate (XtendFlexTM) will be released this season. The addition of glufosinate and dicamba will result in two additional modes of action to be applied in crop. The double knock has proven successful in managing glyphosate resistant weeds in fallow. Substituting glufosinate for paraquat as the follow-up herbicide should be an effective way to increase weed efficacy and manage herbicide resistance.
In a glasshouse experiment, treatments containing glyphosate, dicamba and clethodim (grasses) and glyphosate mixtures with dicamba or clethodim were applied with follow-up glufosinate applied at 1, 3, 7 and 10 days later. These combinations were applied to glyphosate-resistant and -susceptible populations of Conyza bonariensis, Sonchus oleraceus, Chloris virgata, Chloris truncata and Echinochloa colona.
Total control of C. bonariensis was achieved with dicamba and glyphosate+dicamba followed by glufosinate at all timing intervals. Effective control of S. oleraceus was achieved with dicamba and glyphosate+dicamba glufosinate at all timing intervals. Control of C. virgata was achieved with glyphosate, clethodim or glyphosate+clethodim glufosinate 7 and 10 days later. Control of C. truncata was inconsistent, with the most effective treatment being glyphosate+clethodim glufosinate 10 days later. E. colona was controlled with all treatments apart from glyphosate alone on the glyphosate-resistant population
Pyramidobacter sp. strain YE332 genome sequencing
No full textPyramidobacter sp. strain YE332 was isolated from a continuous batch fermentation of bovine rumen fluid maintained under anaerobic conditions and supplied with Leucaena cv Cunningham leaf material. This isolate is representative of the phylum Synergistota and may play a role in protein degradation within the rumen
Molecular and morphological analysis supports the transfer of the monotypic Indonesian genus Septogarcinia Kosterm. to Garcinia (Clusiaceae)
Get PDFBased on molecular phylogenetic analysis and an assessment of fruit and pollen characters, the transfer of Septogarcinia sumbawaensis Kosterm., endemic to Sumbawa Island, Indonesia and the sole member of the genus Septogarcinia, to Garcinia is strongly supported. The formal transfer of S. sumbawaensis to Garcinia (as G. sumbawaensis; the current name is G. septogarcinia) was based on morphological studies only. Phylogenetic analysis of nuclear internal transcribed spacer (ITS) sequences supports a placement of G. septogarcinia in Garcinia Section Brindonia. The distinctive dehiscent fruit, cited by Kostermans as justification for erecting Septogarcinia, is interpreted as an autapomorphy for this species in Garcinia. Pollen exine ornamentation is similar to G. griffithii, G. gummi-gutta var. gummi-gutta, G. mestonii, Garcinia sp. (Maluku) and Garcinia sp. (Batulanteh, Sumbawa)
Application of X-ray computed tomography in soil and plant -a review
Get PDFX-ray computed tomography (X-ray CT) is a non-destructive method of soil analysis which can provide three-dimensional (3D) view, quantitative information of the internal organization of the soil. In this paper, we discuss the potential application of X-ray CT in characterization of soil properties like porosity and pore size distribution (PSD), root architecture, soil phase classification, water and solute transport in soil, and highlight the research during last 10–15 years. Here, we review the recent development of X-ray CT in soil science, use of artificial intelligence and machine learning in image analysis, point out the major challenges associated with its use, discuss few improvements to overcome these difficulties and elaborate the possible future technological developments for non-invasive/destructive soil characterization by integrating X-ray CT with recently available complementary techniques
Identifying compatible waterborne timber preservatives and fire retardants for use in a VPI system: a practical approach
No full textTo enhance the use and suitability of timber in all applications in both exterior and interior settings, timber typically needs to be treated with a preservative and/or a fire retardant chemical. Combining fire retardants with preservatives into a single treatment process has been a long-term aim of researchers in the timber preservative industry because of the significant logistic and economic advantages. This trial explored combining commercially available timber treatment preservatives and fire retardants in a pilot trial to target either H3 (outdoor, above ground) and BAL29 (fire performance) or H2F (internal framing) and Group 1 (fire performance). These combined samples were assessed for stability and feasibility for use in either a vacuum pressure facility or a spray application for the treatment of timber. Of the sixty fire retardant and preservative combinations, a total of twenty-two combinations recorded satisfactory (or better) performance. Each fire retardant product was compatible with two or more common preservatives. These results, coupled with further research, could significantly change the treatment process in Australia and improve the performance and longevity of timber in bushfires, grassfires and internal applications
Identifying innovation discourses for nitrogen management in the sugarcane sector in Great Barrier Reef catchments using Q-methodology
Get PDFDissolved inorganic nitrogen (DIN) run-off from sugarcane farms along Australia's Great Barrier Reef (GBR) coast is implicated in poor catchment water quality and putting pressure on reef health. Reducing DIN is the focus of innovative policies to cut pollution and to maximize social benefit across economic sectors. We use Q-methodology to gain insight into discourses present amongst sugarcane sector stakeholders in GBR catchments. Issue statements, which we aligned with concepts from the Theory of Planned Behaviour, were ranked and correlations identified to generate factors that informed our descriptions of discourses. We found four discourse groups we called sector stalwarts, scientific rationalists, economic maximisers, and sector defenders. We also collected respondent demographic data from which we could judge the propensities of respondent groups to identify with different discourses. This information can help industry innovators and policymakers identify the attributes, mindsets, and appropriate language metaphors for engaging stakeholders in reducing catchment pollution
Mechanical Performance and Bond Integrity of Finger Jointed High-Density Sub-Tropical Hardwoods for Residential Decking
Get PDFFinger jointing has long been a method of extending the longitudinal span of short-length timber pieces through a tooth-like profile of a nominated length and bonded with adhesive. With the high-density hardwood resource in the sub-tropics, local industries have found it difficult to obtain adequate bond integrity for high moisture areas and outdoor applications, where a good bond is governed by the dry modulus of rupture (MOR) and the percentage of wood fibre present in the separated joint after exposure to water impregnation. This paper presents the finger joint performance in terms of MOR, stiffness (MOE), and wood fiber amount (WFA) under different variables, joint profile (10 and 20 mm long fingers) using two structurally rated adhesives (a single-component polyurethane (1C-PUR) and resorcinol formaldehyde (RF)) on spotted gum (Corymbia citriodora) and Darwin stringybark (Eucalyptus tetrodonta) jointed boards. Dry bending strength or MOR testing indicated the 20 mm joints with the PUR adhesive had the best performance across both tested species compared to the RF adhesive. The measured MOE of the joints showed the RF samples to have higher MOE (7% to 13%) than the PUR samples for both joint sizes and species. Testing of joint durability through water impregnation resulted in MOR and MOE values decreasing by up to 50% for the RF and PUR joints. Conversely, the performance of water-impregnated joints after being allowed to re-condition to a 12% equilibrium moisture content produced a regain of MOR for the PUR joints across both species of 30% to 40%. Furthermore, it was found that the WFA increased for the PUR samples between the water-impregnated samples and the re-conditioned samples