981 resultados para Green Vegetable Bug
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Male Nezara viridula produce sex pheromones from many independent single cells, each with a duct that opens onto the ventral abdominal surface. Despite the presence of along duct and an associated end complex (in the form of a cupule and microvillus saccule), the structural organization of the cells that comprise the gland conform to Class 1 epidermal gland cell classification : a single cell surrounds the entire secretory complex. Each cuticular cupule contains a central bed of filaments and opens into a narrow tubular ductule that leads from the base of the cupule through the epidermis to the cuticle to open externally as a pore. The cuticle of the cupule is continuous with that of the ductule and has the appearance of three layers, although the inner (middle) layer may be a gap formed during construction of the complex. In young adult males, just molted, the ultrastructure of the cells and their inclusions indicate that they are not active. The region of the cell that is distal to the abdominal cuticle is reduced and the proximal region, surrounding the duct, is enlarged when compared with sexually mature (3-4 weeks old) adult males. At maturity the pheromone cells are enlarged distally around the cupule, but are reduced to a narrow sleeve proximally, around the ductule. Two characteristic cell profiles are evident, based on the shape of the cupule and the organelle content. Type A shows a broad opening to the cupule, an abundance of mitochondria, and few vesicular bodies. Type B has an elongated, narrow, vase-like opening to the cupule, few mitochondria, and numerous vesicular bodies. Type B cells are smaller and more abundant than Type A. Distribution within the epidermal layer also differs. It is likely that the different types represent cells producing different secretion profiles. However, the secretions retained by the standard fixation protocol within mature cells of both types look similar and appear to collect as crystalline bodies within the lumen. This may represent a common storage mechanism.
Improved understanding of the damage, ecology, and management of mirids and stinkbugs in Bollgard II
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In recent years mirids and stinkbugs have emerged as important sucking pests in cotton. While stinkbugs are causing damage to bolls, mirids are causing damage to seedlings, squares and bolls. With the increasing adoption of Bollgard II and IPM approaches the use of broad-spectrum chemicals to kill Helicoverpa has been reduced and as a result mirids and stinkbugs are building to levels causing damage to bolls later in crop growth stages. Studies on stinkbugs by Dr Moazzem Khan revealed that green vegetable bug (GVB) caused significant boll damage and yield loss. A preliminary study by Dr Khan on mirids revealed that high mirid numbers at later growth stages also caused significant boll damage and that damage caused by mirids and GVB were similar. Mirids and stinkbugs therefore demand greater attention in order to minimise losses caused by these pests and to develop IPM strategies against these pests to enhance gains in IPM that have been made with Bt-transgenic cotton. Progress in this area of research will maintain sustainability and profitability of the Australian cotton industry. Mirid damage at early growth stages of cotton (up to squaring stage) has been studied in detail by Dr Khan. He found that all ages of mirids cause damage to young plants and damage by mirid nymphs is cumulative. Maximum damage occurs when the insect reaches the 4th and 5th nymphal stages. He also found that mirid feeding causes shedding of small and medium squares, and damaged large squares develop as ‘parrot beak’ bolls. Detailed studies at the boll stage, such as which stage of mirids is most damaging or which age boll is most vulnerable to feeding, is lacking. This information is a prerequisite to developing an IPM strategy for the pest in later crop growth stages. Understanding population change of the pest over time in relation to crop development is an important aspect for developing management strategies for the pest which is lacking for mirids in BollgardII. Predators and parasitoids are integral components of any IPM system and play an important part in regulating pest populations. Some generalist predators such as ants, spiders, damsel bugs and assassin bugs are known to predate on mirids. Nothing is known about parasitoids of mirids. Since green mirid (GM), Creontiades dilutus, is indigenous to Australia it is likely that we have one or more parasitoids of this mirid in Australia, but that possibility has not been investigated yet. The impact of the GVB adult parasitoid, Trichopoda giacomelli, has been studied by Dr Khan who found that the fly is established in the released areas and continues to spread. However, to get wider and greater impact, the fly should be released in new locations across the valleys. The insecticides registered for mirids and stinkbugs are mostly non-selective and are extremely disruptive to a wide range of beneficial insects. Use of these insecticides at stage I and II will minimise the impact of existing IPM programs. Therefore less disruptive control tactics including soft chemicals for mirids and stinkbugs are necessary. As with soft chemicals, salt mixtures, biopesticides based on fungal pathogens and attractants based on plant volatiles may be useful tools in managing mirids and stinkbugs with less or no disruption. Dr Khan has investigated salt mixture against mirids and GVB. While salt mixtures are quite effective and less disruptive, they are quite chemical specific. Not all chemicals mixed with salt will give the desired benefit. Therefore further investigation is needed to identify those chemicals that are effective with salt mixture against mirids and 3 of 37 GVB. Dr Caroline Hauxwell of DPI&F is working on fungal pathogen-based biopesticides against mirids and GVB and Drs Peter Gregg and Alice Del Socorro of Australian Cotton CRC are working on plant volatile-based attractants against mirids. Depending on their findings, inclusion of fungal-based biopestcides and plant volatile-based attractants in developing a management system against mirids and stinkbugs in cotton could be an important component of an IPM approach.
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This paper reviews the current research on phytochemical composition and non-Western traditional culinary food preparation and health uses of papaya. Only ripe papaya fruit flesh is normally eaten in Western countries. The orange or red flesh is an excellent source of pro-vitamin A and ascorbic acid. In South-East Asia, both ripe and green fruit are used and additionally leaves are popularly consumed either raw in salad or cooked as a green vegetable. The leaves contain alkaloids as well as quercetin and kaempferol as the main phenolic compounds. In contrast to Western use papaya has a reputation as a medicinal plant in tropical countries where it is grown. Different plant parts such as fruit, leaf, seed, root, bark and flowers have been used as health treatments. These have included use as topical dressings for treating ulcers and dermatitis, gastrointestinal uses such as antihelminthic and antibacterial activity treatments and traditional uses for fertility control. The differences in use for food and health illustrate potential applications and nutritional benefits of the plant which require further research. With better verification the health applications of papaya could be more widely adopted into Western culture.
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随着城市化进程的快速推进,大量蔬菜等食物由农村向城市输送,因此促进了城郊结合部蔬菜基地的发展。然而,城市化发展却导致越来越严重的城市和城郊土壤和大气污染,加上现代化生产中化肥和农用化学品的大量使用等,使得重金属在菜园土中大量积累,并可能通过食物链进入人体,威胁人类身体健康。因此,对重金属在土壤-蔬菜体系间迁移的生物地球化学行为的研究是我们了解和防治蔬菜重金属污染、促进绿色作物生产和保护人类健康的关键。 本文选择世界典型喀斯特地区的贵阳市市郊的菜园土-蔬菜体系为主要研究对象,通过系统地对土壤、主要蔬菜和大气沉降物质的元素分析以及铅同位素分析,对研究区域菜园土的主要理化性质、土壤(以及剖面)和蔬菜样品中重金属Cu、Pb、Zn和Cd的含量变化、菜园土以及土壤剖面重金属的形态分布等特征进行了研究。利用微量元素地球化学以及同位素地球化学理论,并结合土壤学研究理论和方法探讨了重金属在菜园土(石灰土和黄壤)和蔬菜体系间的赋存形态、重金属元素的来源、迁移与转化规律及其中的主要控制因素。 主要研究结果认为:贵阳市郊菜园土重金属元素含量变化与土壤母质显著相关,黄壤类型菜园土处于中度污染水平,石灰土类型菜园土处于轻度污染水平。菜园土中重金属形态以残余态为主,其次为有机结合态,再次为铁锰氧化物结合态和酸可提取态。土壤剖面中,菜园土表层大多数重金属含量高于背景剖面,其余各层吻合度较高。土壤剖面中重金属的形态分布仍以残余态为主,菜园土剖面上各元素的生物可利用态即酸可提取态、氧化物结合态和有机结合态则均要高于背景剖面,Pb和Zn主要受到有机结合态的影响,而Cd则三种形态的含量均高于背景剖面,种种迹象表明人为活动增加了菜园土重金属的活性和生物有效性,且以有机结合态的改变最为显著。 蔬菜中红薯可食部位的各项重金属富集系数均大于其他蔬菜,最容易受到土壤中重金属的影响;在土壤-蔬菜体系中,重金属元素含量的分布总体特征为菜园土>根>茎叶>果实,体系内元素的迁移在土壤/蔬菜根界面上最为关键,起着控制作用,此界面上各元素的迁移系数顺序为Cd>>Cu,Zn>Pb,大多数重金属元素在黄壤类型的菜园土中的迁移系数要小于石灰土类型的;在土壤-红薯和土壤-辣椒体系中,Cd的迁移系数随土壤pH的增加而降低,而其余元素的迁移系数则随土壤pH的增加而增加;土壤主成分与土壤理化性质对重金属形态分布有显著影响,但BCR连续提取法得到的土壤中重金属元素的各生物可利用态的含量与蔬菜根部的含量相关性不大;覆膜种植方式使土壤pH由4.5降低到3.8,并改变了其它物化参数,从而影响重金属的形态分布及其在蔬菜体内的含量分布特征,极可能增加农业系统中重金属的环境风险;铅稳定同位素分析表明,土壤中的铅主要来自于母岩的风化,蔬菜中放射成因铅明显略低于菜园土,菜园土和蔬菜中铅同位素组成在208Pb/206Pb对207Pb/206Pb的分布图上呈直线分布(在菜园土-蔬菜体系中,土壤样品、蔬菜不同部位的样品、以及雨水样品的铅同位素组成的分布也形成了极好的直线),显示明显的两端元混合体系;根据各端元物质铅同位素组成计算,土壤铅对蔬菜根部、茎叶的贡献值由71.8%~77.7%降低到16.0%~45.4%之间,大气铅的贡献则沿根向茎叶和果实逐渐增加,研究结果显示大气污染对蔬菜重金属Pb的贡献不可忽视。
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The stink bugs genus Atopozelus (Hemiptera: Reduviidae) is native in the Americas, with five described species of which only three have been recorded in Brazil. In August 2007, Eucalyptus camaldulensis leaves infested by lerp psyllid were collected and taken to the Forest Pest Biological Control Laboratory situated at São Paulo State University. A small green stink bug, identified as Atopozelus opsimus Elkins (Hemiptera: Reduviidae) that fed on nymphs and adult psyllids, was found on the leaves. These stink bugs presented phytophagy, omnivory and ability in opening the lerp (shell) that protect the psyllid. A. opsimus has demonstrated unusual particularities, different from many biological control agents found in nature; this predator thus deserves more attention for its potential to be evaluated.
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The ability of the stink bug (Nezara viridula) to induce and/or increase production of chemical defenses, i.e., flavonoids, in immature seeds of five genotypes of soybean (BR-16, IAC-100, PI 227687, PI 229358, and PI 274454) was investigated under greenhouse and laboratory conditions. Samples from pods of each genotype damaged by stink bug were analyzed for flavonoid content with high performance liquid chromatography. A dual-choice test was conducted to evaluate the feeding preference of N. viridula comparing BR-16 pods treated with extracts of PI 227687 seeds (with and without stink-bug injury), with water-treated pods. Seeds of PI 227687 damaged by N. viridula presented the highest concentration (352 mug/g) of daidzin (4'-hydroxyisoflavone-7-glucoside). The same trend was observed with genistin (4',5,7-trihydroxyisoflavone-7-glucoside): PI 227687 contained 142.4 mug/g, PI 274454, 31.6 mug/g, and PI 229358, 38.9 mug/g. Seeds damaged by stink bugs had higher isoflavone contents (daidzin and genistin), compared to controls. However, after being damaged, PI 274454 and PI 229358 produced less genistin than the other genotypes and no differences in concentration between damaged and nondamaged plants of this genotypes were observed. The numbers of observations of the insect feeding and the numbers of stylet sheaths left in water-treated BR-16 pods were greater than in those treated with PI 227687 extracts. The insects fed for longer periods on BR-16 pods treated with extract of PI 227687 without injury compared to those that were treated with extract of PI 227687 previously injured by stink bugs. Extracts of PI 227687 pods ( damaged or not) were deterrent to adults of N. viridula, and insect injury increased concentrations of daidzin and genistin in PI 227687 seeds. The deterrence seemed to be more pronounced after pods had suffered stink-bug injury.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Checklist Amer. imprints,
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The use of nitrification inhibitors, in combination with ammonium based fertilisers, has been promoted recently as an effective method to reduce nitrous oxide (N2O) emissions from fertilised agricultural fields, whilst increasing yield and nitrogen use efficiency. Vegetable cropping systems are often characterised by high inputs of nitrogen fertiliser and consequently elevated emissions of nitrous oxide (N2O) can be expected. However, to date only limited data is available on the use of nitrification inhibitors in sub-tropical vegetable systems. A field experiment investigated the effect of the nitrification inhibitors (DMPP & 3MP+TZ) on N2O emissions and yield from a typical vegetable production system in sub-tropical Australia. Soil N2O fluxes were monitored continuously over an entire year with a fully automated system. Measurements were taken from three subplots for each treatment within a randomized complete blocks design. There was a significant inhibition effect of DMPP and 3MP+TZ on N2O emissions and soil mineral N content directly following the application of the fertiliser over the vegetable cropping phase. However this mitigation was offset by elevated N2O emissions from the inhibitor treatments over the post-harvest fallow period. Cumulative annual N2O emissions amounted to 1.22 kg-N/ha, 1.16 kg-N/ha, 1.50 kg-N/ha and 0.86 kg-N/ha in the conventional fertiliser (CONV), the DMPP treatment, the 3MP+TZ treatment and the zero fertiliser (0N) respectively. Corresponding fertiliser induced emission factors (EFs) were low with only 0.09 - 0.20% of the total applied fertiliser lost as N2O. There was no significant effect of the nitrification inhibitors on yield compared to the CONV treatment for the three vegetable crops (green beans, broccoli, lettuce) grown over the experimental period. This study highlights that N2O emissions from such vegetable cropping system are primarily controlled by post-harvest emissions following the incorporation of vegetable crop residues into the soil. It also shows that the use of nitrification inhibitors can lead to elevated N2O emissions by storing N in the soil profile that is available to soil microbes during the decomposition of the vegetable residues over the post-harvest phase. Hence the use of nitrification inhibitors in vegetable systems has to be treated carefully and fertiliser rates need to be adjusted to avoid excess soil nitrogen during the postharvest phase.
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The field bean (Dolichos lab lab ; Tamil name, Mochai ; Kanarese, Avarai) is a legume which is widely cultivated in South India often as a mixed crop with cereals. The kernel of the seed enters into the diet of may South Indian households, and in the Mysore State the seed are used as a delicacy when they are green for over four months in the year. The haulm, husk and pods are commonly used a fodder. As the kernel which is widely used as an article of food and considered to be very nutritious, contains about 24% of protein hitherto uninvestigated and as the quality of protein plays an important role in nutrition, the present work was undertaken.
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The availability and quality of irrigation water has become an issue limiting productivity in many Australian vegetable regions. Production is also under competitive pressure from supply chain forces. Producers look to new technologies, including changing irrigation infrastructure, exploring new water sources, and more complex irrigation management, to survive these stresses. Often there is little objective information investigating which improvements could improve outcomes for vegetable producers, and external communities (e.g. meeting NRM targets). This has led to investment in inappropriate technologies, and costly repetition of errors, as business independently discover the worth of technologies by personal experience. In our project, we investigated technology improvements for vegetable irrigation. Through engagement with industry and other researchers, we identified technologies most applicable to growers, particularly those that addressed priority issues. We developed analytical tools for ‘what if’ scenario testing of technologies. We conducted nine detailed experiments in the Lockyer Valley and Riverina vegetable growing districts, as well as case studies on grower properties in southern Queensland. We investigated root zone monitoring tools (FullStop™ wetting front detectors and Soil Solution Extraction Tubes - SSET), drip system layout, fertigation equipment, and altering planting arrangements. Our project team developed and validated models for broccoli, sweet corn, green beans and lettuce, and spreadsheets for evaluating economic risks associated with new technologies. We presented project outcomes at over 100 extension events, including irrigation showcases, conferences, field days, farm walks and workshops. The FullStops™ were excellent for monitoring root zone conditions (EC, nitrate levels), and managing irrigation with poor quality water. They were easier to interpret than the SSET. The SSET were simpler to install, but required wet soil to be reliable. SSET were an option for monitoring deeper soil zones, unsuitable for FullStop™ installations. Because these root zone tools require expertise, and are labour intensive, we recommend they be used to address specific problems, or as a periodic auditing strategy, not for routine monitoring. In our research, we routinely found high residual N in horticultural soils, with subsequently little crop yield response to additional nitrogen fertiliser. With improved irrigation efficiency (and less leaching), it may be timely to re-examine nitrogen budgets and recommendations for vegetable crops. Where the drip irrigation tube was located close to the crop row (i.e. within 5-8 cm), management of irrigation was easier. It improved nitrogen uptake, water use efficiency, and reduced the risk of poor crop performance through moisture stress, particularly in the early crop establishment phases. Close proximity of the drip tube to the crop row gives the producer more options for managing salty water, and more flexibility in taking risks with forecast rain. In many vegetable crops, proximate drip systems may not be cost-effective. The next best alternative is to push crop rows closer to the drip tube (leading to an asymmetric row structure). The vegetable crop models are good at predicting crop phenology (development stages, time to harvest), input use (water, fertiliser), environmental impacts (nutrient, salt movement) and total yields. The two immediate applications for the models are understanding/predicting/manipulating harvest dates and nitrogen movements in vegetable cropping systems. From the economic tools, the major influences on accumulated profit are price and yield. In doing ‘what if’ analyses, it is very important to be as accurate as possible in ascertaining what the assumed yield and price ranges are. In most vegetable production systems, lowering the required inputs (e.g. irrigation requirement, fertiliser requirement) is unlikely to have a major influence on accumulated profit. However, if a resource is constraining (e.g. available irrigation water), it is usually most profitable to maximise return per unit of that resource.
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This paper is a hybrid starting with an overview and history of biodiesel synthesis and finishing with a description with some of our latest unpublished data. Initially, we examine "green" ways of obtaining biodiesel using ionic liquids, which can have an acidic or basic functionality, and can function both as a solvent and catalyst for the (trans)esterification reaction to obtain biodiesel. Both animal and vegetable resources can be utilized as a resource for (trans)esterification reactions depending on the geographical area. Biodiesel is of great interest because it enables motor vehicle transport using a renewable resource, while reducing the amount of carbon dioxide from fossil fuels being released into the environment.
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Pea-shoots are a new option as ready-to-eat baby-leaf vegetable. However, data about the nutritional composition and the shelf-life stability of these leaves, especially their phytonutrient composition is scarce. In this work, the macronutrient, micronutrient and phytonutrients profile of minimally processed pea shoots were evaluated at the beginning and at the end of a 10-day storage period. Several physicochemical characteristics (color, pH, total soluble solids, and total titratable acidity) were also monitored. Standard AOAC methods were applied in the nutritional value evaluation, while chromatographic methods with UV–vis and mass detection were used to analyze free forms of vitamins (HPLC-DAD-ESI-MS/MS), carotenoids (HPLC-DAD-APCI-MSn) and flavonoid compounds (HPLC-DAD-ESI-MSn). Atomic absorption spectrometry (HR-CS-AAS) was employed to characterize the mineral content of the leaves. As expected, pea leaves had a high water (91.5%) and low fat (0.3%) and carbohydrate (1.9%) contents, being a good source of dietary fiber (2.1%). Pea shoots showed a high content of vitamins C, E and A, potassium and phosphorous compared to other ready-to-eat green leafy vegetables. The carotenoid profile revealed a high content of β-carotene and lutein, typical from green leafy vegetables. The leaves had a mean flavonoid content of 329 mg/100 g of fresh product, mainly composed by glycosylated quercetin and kaempferol derivatives. Pea shoots kept their fresh appearance during the storage being color maintained throughout the shelf-life. The nutritional composition was in general stable during storage, showing some significant (p < 0.05) variation in certain water-soluble vitamins.