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Some plant-parasitic nematodes need to spend a significant part of their life cycles within plants while others have long-lasting biotrophic interactions with their hosts. In each case, these nematodes will need to suppress host defences. Large numbers of candidate effectors - proteins that nematodes introduce into their hosts - have been identified from a variety of nematode species as a result of genome and transcriptome projects. There is now a focus on functional characterization of these proteins. This has led to the identification of nematode proteins that suppress different types of host defence responses. Here we review progress towards understanding how nematodes manipulate host defences and how hormone signalling related to defence responses is targeted by nematodes. [ABSTRACT FROM AUTHOR]

Aphids are economically important pests that cause extensive feeding damage and transmit viruses. While some species have a broad host range and cause damage to a variety of crops, others are restricted to only closely related plant species. While probing and feeding aphids secrete saliva, containing effectors, into their hosts to manipulate host cell processes and promote infestation. Aphid effector discovery studies pointed out parallels between infection and infestation strategies of plant pathogens and aphids. Interestingly, resistance to some aphid species is known to involve plant resistance proteins with a typical NB-LRR domain structure. Whether these resistance proteins indeed recognize aphid effectors to trigger ETI remains to be elucidated. In addition, it was recently shown that unknown aphid derived elicitors can initiate reactive oxygen species (ROS) production and callose deposition and that these responses were dependent on BAK1 (BRASSINOSTERIOD INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1) which is a key component of the plant immune system. In addition, BAK-1 contributes to non-host resistance to aphids pointing to another parallel between plant-pathogen and -- aphid interactions. Understanding the role of plant immunity and non-host resistance to aphids is essential to generate durable and sustainable aphid control strategies. Although insect behavior plays a role in host selection and non-host resistance, an important observation is that aphids interact with non-host plants by probing the leaf surface, but are unable to feed or establish colonization. Therefore, we hypothesize that aphids interact with nonhost plants at the molecular level, but are potentially not successful in suppressing plant defenses and/or releasing nutrients. [ABSTRACT FROM AUTHOR]

The internet is a useful source of information for United Kingdom planners. Organizations can use the internet and gain ideas about how to set up their own sites with no need to take a course on the subject. The best way to begin learning is to start with a small pilot site which can be viewed by a critical, restricted audience. Feedback is useful, as are some technical skills, and a clear business idea. There are a number of useful sites set up by UK organizations such as the Planning Department of Surrey County Council.

Geographic information systems (GIS) can involve a high outlay, and potential users need to establish why they want the system, before committing themselves. They should also be user-friendly, and it is important to invest in training users. Benefits arising from the use of GIS are related to investment in training and choosing the right system. They are especially useful in population analysis, networking and incident analysis, and also have offer advantages for flexible mapping.

The article discusses and proposes some guidelines that should be followed by a publisher in a developing country like Bangladesh to produce a journal that is comparable with international journals. Publishing a high-quality scientific journal in Bangladesh is indeed a laborious, difficult and tremendous job because of the country's weak economic condition. It has been suggested that the purpose of and success in publishing a scholarly peer-reviewed scientific journal can be achieved provided certain processes are systematically followed. Otherwise, in the long run the sustainability of the journal may be at stake. This article also discusses several journal-related issues and problems that warrant immediate attention of the concerned agencies to pave the way for publishing quality journals. It has been noted that in order to earn a good image in journal publishing, integrated efforts of all concerned are necessary. The article puts forward some suggestions that may bring about positive changes, exert positive impact on the total journal-publication process, and help earn considerable revenues for publishers of scientific journals.

The major constraints to the use of new information tech nology in the developing countries are identified and discus ssed, and related to the setting up of a computerised biblio graphic database system. Examples of existing systems are given to provide guidelines as to how new technology can successfully be used in the developing countries despite these constraints. It is concluded that staff training, international cooperation and socio-political aspects (attitudes) are the prior ity areas for attention by the developing countries. New tech nology can be successfully introduced only if there is the political will and all involved are fully committed to the idea. [ABSTRACT FROM PUBLISHER]

Background: Colony growth on solid media is a simple and effective measure for high-throughput genomic experiments such as yeast two-hybrid, synthetic dosage lethality and Synthetic Physical Interaction screens. The development of robotic pinning tools has facilitated the experimental design of these assays, and different imaging software can be used to automatically measure colony sizes on plates. However, comparison to control plates and statistical data analysis is often laborious and pinning issues or plate specific growth effects can lead to the detection of false-positive growth defects. Results: We have developed ScreenGarden, a shinyR application, to enable easy, quick and robust data analysis of plate-based high throughput assays. The code allows comparisons of different formats of data and different sized arrays of colonies. A comparison of ScreenGarden with previous analysis tools shows that it performs, at least, equivalently. The software can be run either via a website or offline via the RStudio program; the code is available and can be modified by expert uses to customise the analysis. Conclusions: ScreenGarden provides a simple, fast and effective tool to analyse colony growth data from genomic experiments. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes constrain global food security. During parasitism, they secrete effectors into the host plant from two types of pharyngeal gland cells. These effectors elicit profound changes in host biology to suppress immunity and establish a unique feeding organ from which the nematode draws nutrition. Despite the importance of effectors in nematode parasitism, there has been no comprehensive identification and characterisation of the effector repertoire of any plant-parasitic nematode. To address this, we advance techniques for gland cell isolation and transcriptional analysis to define a stringent annotation of putative effectors for the cyst nematode Heterodera schachtii at three key life-stages. We define 717 effector gene loci: 269 "known" high-confidence homologs of plant-parasitic nematode effectors, and 448 "novel" effectors with high gland cell expression. In doing so we define the most comprehensive "effectorome" of a plant-parasitic nematode to date. Using this effector definition, we provide the first systems-level understanding of the origin, deployment and evolution of a plant-parasitic nematode effectorome. The robust identification of the effector repertoire of a plant-parasitic nematode will underpin our understanding of nematode pathology, and hence, inform strategies for crop protection. Author summary: Pathogenic organisms deliver so called "effectors", typically proteins, into their host to alter cell structure and function. Identifying and characterising the repertoire of effector-encoding genes is requisite to understanding infection. Here we advance methods and understanding, in combination with an extensive literature survey, to define a stringent annotation of putative effectors for the plant-parasitic cyst nematode, Heterodera schachtii. Using this effector definition, we provide the first systems-level understanding of the origin, deployment, and evolution of a plant-parasitic nematode effectorome. Given that plant-parasitic nematodes are major, and in some cases dominant, threats to global food security, it is widely cited that understanding how they infect their host (i.e. effectors) will deliver routes to alleviate their threat to agriculture. [ABSTRACT FROM AUTHOR]