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11.
ABSTRACT

Transitioning from trials to pest control tool, the efficacy of controlling wasps Vespula vulgaris and V. germanica using Vespex® wasp bait was tested in 2015. Vespex® is a protein-based bait matrix with 0.1% fipronil. Five sites ranging <300 to >2000 ha and over 5500 ha in total had bait stations placed 300 × 50 m apart and received one application of Vespex®. Wasp nest traffic rates declined 93% in four days at one site, and over 97% after 20–38 days at all other sites. Measured honeydew availability also improved post wasp control. Further demonstrating feasibility, five different agencies worked closely with government leading many programme aspects. Vespex® was made more widely available in New Zealand towards the end of 2015. Web page information showed ~30% of all territorial authorities nationally are engaging in pest wasp problems. This signals a future potential in the way that pest wasps might be managed in a community context for social, economic and biodiversity conservation objectives.  相似文献   
12.
A field study was carried out from April 2014 to August 2014 for two consecutive planting cycles of Zea mays L. on Nyalau Series (Typic Tualemkuts) to determine the short-term effects of co-application of chemical fertilizers, rice straw compost, and clinoptilolite zeolite on (i) ammonium adsorption and desorption, (ii) nitrogen, phosphorus, and potassium uptake and use efficiency, and (iii) yield of Zea mays L. (cobs). Amending urea with rice straw compost and clinoptilolite zeolite improved nitrogen use efficiency because of temporary adsorption and desorption of ammonium on the exchange sites of compost and clinoptilolite zeolite. Combined use of chemical fertilizers, rice straw compost, and clinoptilolite zeolite enhanced uptake of nitrogen, phosphorus, potassium, calcium, and magnesium. Co-application of chemical fertilizers, rice straw compost, and clinoptilolite zeolite can improve the availability of soil nutrients. This approach can also improve nutrient use efficiency and yield of Zea mays L.  相似文献   
13.
Tropical acid soils are highly weathered as they exist under tropical environment with high rainfall and temperature throughout the year, which affects nitrogen availability. Soil organic nitrogen is important in estimating soil nitrogen availability. The combined use of urea and compost in this study was carried out to decrease sole dependence on urea, buffer soil acidification, and reduce nitrogen losses through leaching. Thus, soil buffering capacity, incubation, and organic nitrogen fractionation studies were conducted to determine soil buffering capacity, availability of total nitrogen, organic fractions nitrogen, and inorganic nitrogen in soil after 90 days of incubation following compost. Soil pH, buffering capacity, total nitrogen, organic nitrogen fractions, exchangeable ammonium, and available nitrate were higher in all treatments with compost and combined use of urea and compost. Total hydrolyzable nitrogen, ammonium-nitrogen, (ammonium + amino sugar)-nitrogen, amino sugar-nitrogen, and amino acid-nitrogen were higher in soils with urea and compost suggesting that decomposition of soil organic fractions nitrogen into inorganic nitrogen (ammonium and available nitrate was affected by the addition of urea and compost. Urea can be amended with compost to regulate availability nitrogen in soil for crop use.  相似文献   
14.
Application of urea in lowland rice fields leads to ammonia (NH3) volatilization and environmental pollution, and diminishes nitrogen recovery by rice (Oryza sativa L.). Amending urea with biochar could reduce NH3 loss from urea as well as improve chemical properties of acid soils. An incubation study was conducted using a closed-dynamic air flow system to determine NH3 volatilization from urea and chemical properties of an acid soil (Typic Paleudults). The soil was mixed with three rates of chicken litter biochar (20, 40, and 60 g pot?1) and 1.31 g urea. Mixing an acid soil with biochar (60 g pot?1) in waterlogged to stimulate conditions in paddy condition significantly reduced NH3 loss and total titratable acidity. Biochar application also increased soil pH, total nitrogen, available nitrate, organic matter, total organic carbon, total carbon, available phosphorus, and exchangeable cations. Thus, chicken litter biochar can be used to reduce urea-N loss and ameliorate chemical properties of acid soils. This aspect is being embarked on in our on-going field experiments.  相似文献   
15.
To avoid environmental pollution due to excessive use of inorganic fertilizers, it is essential to increase the availability of nutrients using environmentally friendly resources, such as composts and clinoptilolite zeolite, in soil fertility management. In this study, an attempt was made to use different rates of inorganic fertilizers, compost, and clinoptilolite zeolite to correct the ongoing excessive use of inorganic fertilizers. A pot study using maize (Zea mays L.) as a test crop was carried out to determine the effects of amending inorganic fertilizers with compost and clinoptilolite zeolite on: (i) selected soil chemical properties, and (ii) N, P, and K uptake and use efficiency in maize cultivation. The pot study was conducted for 45 days (tasseling stage of maize). Amending inorganic fertilizers with compost and clinoptilolite zeolite increased soil total N, exchangeable Ca, Mg, K, and available P. Furthermore, P and K uptake and use efficiency of maize were significantly improved upon amending inorganic fertilizers with compost and clinoptilolite zeolite. Soil chemical properties and productivity of maize on acid soils can be improved through co-application of compost and clinoptilolite zeolite. However, field application of the authors’ findings is being evaluated in an on-going field experiment.  相似文献   
16.
Harovinton, a variety of tofu type soybean, and 11 derived null soybean genotypes lacking specific glycinin (11S) and beta-conglycinin (7S) protein subunits were investigated to determine whether changes in protein composition affected the protein recovery in soymilk and its soluble fractions after various centrifugation steps. As both heating and homogenization have a marked effect on the increase in protein solubility, the changes occurring during these processing steps were studied for each soybean genotype. Harovinton and 11S-null genotypes showed significantly higher protein yields than the other genotypes evaluated. Subunits of group I (A(1), A(2)) of glycinin had a negative impact on protein solubility in all treatments, but this effect was the greatest in unheated soymilk samples. Samples containing a high beta-conglycinin to glycinin ratio showed an effect of heating on the solubility of the protein, as beta-conglycinin subunits aggregate with heating. The presence of the alpha' subunit of beta-conglycinin aids in the recovery of protein in the supernatant prepared from lines containing group I (A(1,4) A(2)) glycinin. The results of this study will help determine which specific protein composition will confer an increased stability in soymilk and soymilk-derived products.  相似文献   
17.
This study was conducted to determine the performance of new egg custard formula to replace Artemia sp. on the growth and survival of the giant freshwater prawn, Macrobrachium rosenbergii, larvae. Five experimental diets were tested with triplicate treatments: ART (Artemia sp.), ART‐MIX (Artemia sp. + egg custard MIX: a mixture of shrimp, squid, and bivalve meal‐based egg custard, with palm oil), ART‐PBM (Artemia sp. + PBM, poultry byproduct meal‐based egg custard with fish oil), egg custard MIX only, and egg custard PBM only. All experimental diets were tested after 9 d (stage VI) of feeding Artemia sp. to prawn larvae. The stocking density was set at 100 larvae/L in a clear water tank culture system. Results indicated that the highest survival was recorded in the treatment of ART‐PBM (46.07 ± 0.84%) and the lowest was in the MIX treatment (8.87 ± 0.51%). ART‐PBM and ART‐MIX diets successfully reduced the rearing period and improved survival from larval to postlarval stage by 19 and 65%, respectively, compared with the ART diet. However, the use of MIX and PBM alone increased the rearing period up to 11%. The feeding regime of ART‐PBM and ART‐MIX has provided nutritional advantages and can be successfully practiced in the hatchery of M. rosenbergii larvae. The innovative approach of using PBM and palm oil in the egg custard formulation in this study can provide prawn hatchery operators with more options in terms of dietary ingredients and cost‐effective solutions.  相似文献   
18.
The stability, crystallization, and melting behavior of canola stearin (CaSt) solid lipid nanoparticle dispersions (SLN) and canola oil-in-water emulsions (COE) with 10 wt % Poloxamer 188 (P188) or Tween 20 (T20) with and without 0.1 wt % β-carotene (BC) were investigated. Particles or droplets with diameters in the range of 115 nm were formed and stable for up to 90 days at 4 or 20 °C. Polymorphism was affected by surfactant type; that is, only β versus both β' and β were observed for the P188 and T20 SLN, respectively. According to Cryo-TEM, the emulsions and SLN were spherical versus platelet-like structures, respectively, with differences observed between SLN with P188 or T20. More surfactant was interfacially adsorbed in the SLN versus COE. Incorporation of BC at 0.1 wt % had no impact on SLN or COE size, polymorphism, or melting behavior. Less BC degradation was observed for the SLN versus COE and during storage at 4 versus 20 °C (p < 0.05).  相似文献   
19.
Wilt and root rot disease in plants has been caused mainly by Fusarium species. Previous studies reported that members of the Fusarium oxysporum species complex (FOSC) were usually associated with this disease, but there has been no report of it being caused in rice by specific Fusarium species. However, in this study, Fusarium commune was identified and characterized as a causal agent of wilt and root rot disease of rice. Four Fusarium isolates (BD005R, BD014R, BD019R, and BD020R) were obtained from different parts (root, stem, and seeds) of diseased rice plants. In morphological studies, these isolates produced key characteristics of F. commune, such as long and slender monophialides, polyphialides, and abundant chlamydospores. In molecular studies, the isolates were identified as F. commune based on sequences of the translation elongation factor 1-α (TEF1) gene that had 99.7%–100% sequence identity with the reference strain F. commune NRRL 28058. The phylogenetic tree showed that all four isolates belonged to the F. commune clade. A mating type test determined that three isolates carried MAT1-2. Their teleomorph stage was still unknown. Pathogenicity assays showed that all the isolates produced wilt and root rot symptoms and the isolate BD019R was observed as the most virulent among the isolates. To our knowledge, this is the first report of F. commune causing wilt and root rot disease on rice.  相似文献   
20.
How introduced reptiles cause the loss of endemic reptiles is poorly understood and currently there are no available techniques for dealing with this major conservation issue. We addressed both these problems by investigating the role of the introduced house gecko Hemidactylus frenatus in causing the catastrophic decline and extinction of the endemic night gecko Nactus populations of the Mascarene Islands and how this introduced species can be excluded from habitats on the basis of morphology. Competition for enemy free space was tested in experimental enclosures and showed that H. frenatus displace the endemic Nactus coindemirensis and Nactus durrelli from favoured positions close to and from refugia, thus increasing the risk of predation and exposure to stochastic events. The ability of H. frenatus to grip substrates with their pad-bearing toes was examined, and we demonstrated that naturally occurring substrates with a greater amount of loose surface material of a higher particulate concentration and size excludes H. frenatus, but not Nactus. These findings support the hypothesis that H. frenatus led to the fragmentation and extinction of the endemic Nactus populations and demonstrate that artificial refugia made of a crumbly substrate may be used to limit future disturbances by this gecko and others like it in the Mascarene Islands and elsewhere.  相似文献   
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