Transcriptomics-based analysis using RNA-Seq of the coconut (Cocos nucifera) leaf in response to yellow decline phytoplasma infection

Invasive phytoplasmas wreak havoc on coconut palms worldwide, leading to high loss of income, food insecurity and extreme poverty of farmers in producing countries. Phytoplasmas as strictly biotrophic insect-transmitted bacterial pathogens instigate distinct changes in developmental processes and defence responses of the infected plants and manipulate plants to their own advantage; however, little is known about the cellular and molecular mechanisms underlying host–phytoplasma interactions. Further, phytoplasma-mediated transcriptional alterations in coconut palm genes have not yet been identified. This study evaluated the whole transcriptome profiles of naturally infected leaves of Cocos nucifera ecotype Malayan Red Dwarf in response to yellow decline phytoplasma from group 16SrXIV, using RNA-Seq technique. Transcriptomics-based analysis reported here identified genes involved in coconut innate immunity. The number of down-regulated genes in response to phytoplasma infection exceeded the number of genes up-regulated. Of the 39,873 differentially expressed unigenes, 21,860 unigenes were suppressed and 18,013 were induced following infection. Comparative analysis revealed that genes associated with defence signalling against biotic stimuli were significantly overexpressed in phytoplasma-infected leaves versus healthy coconut leaves. Genes involving cell rescue and defence, cellular transport, oxidative stress, hormone stimulus and metabolism, photosynthesis reduction, transcription and biosynthesis of secondary metabolites were differentially represented. Our transcriptome analysis unveiled a core set of genes associated with defence of coconut in response to phytoplasma attack, although several novel defence response candidate genes with unknown function have also been identified. This study constitutes valuable sequence resource for uncovering the resistance genes and/or susceptibility genes which can be used as genetic tools in disease resistance breeding.

Does firefighting foam affect the growth of some Australian native plants?

Firefighting foams (Class A foams) are an effective and widespread firefighting tool, and are frequently used in environmentally sensitive areas. They are known to be ecologically damaging in aquatic environments; however, their impacts at the plant species or ecosystem level are relatively unknown. Reports of shoot damage to plants, suppressed flowering and changes in plant community composition suggest that the environmental damage caused by their use may be unacceptable. Applications of four levels of foam to seedlings of seven Australian plant species, from five representative and widespread families, showed no detectable impacts on a range of vegetative growth characteristics. The results are encouraging for continued use of firefighting foam in sensitive natural habitats.

CIDB: Chlamydia Interactive Database for cross-querying genomics, transcriptomics and proteomics data

Chlamydiae are important pathogens of humans, birds and a wide range of animals. They are a unique group of bacteria, characterized by their developmental cycle. Chlamydia has been difficult to study because of their obligate intracellular growth habit and lack of a genetic transformation system. However, the past 5 years has seen the full genome sequencing of seven strains of Chlamydia and a rapid expansion of genomic, transcriptomic (RT-PCR, microarray) and proteomic analysis of these pathogens. The Chlamydia Interactive Database (CIDB) described here is the first database of its type that holds genomic, RT-PCR, microarray and proteomics data sets that can be cross-queried by researchers for patterns in the data. Combining the data of many research groups into a single database and cross-querying from different perspectives should enhance our understanding of the complex cell biology of these pathogens. The database is available at: http://www3.it.deakin.edu.au:8080/CIDB/.

Medicinal plants of Malaysia

This article presents information about agricultural news and studies. Pharmacologists know the medicinal properties of the tropical species of Malaysia. Areca catechu is known as a common masticatory drug. An overview of the various medicinal plants, including Andrographis paniculata, Aquilaria malaccenis, and Cassia alata is offered. Malaysian medicinal plants act as strong therapeutic agents for several human diseases.

Medicinal plants of Thailand

This article reveals some common medicinal plants from Thailand.

Surviving suppression : no detectable impacts of Class A foam on soil invertebrates and some Australian native plants

Firefighting foams (Class A foams) are an effective and widespread firefighting tool which are frequently used in environmentally sensitive areas. Firefighting foams are known to be ecologically damaging in aquatic environments, however their impacts at the plant species or ecosystem level are relatively unknown. Reports of shoot damage to plants, suppressed flowering, and changes in plant community composition suggested that the ecological damage caused by their use may be unacceptable. However, applications of foam to seedlings of some Australian plant species from representative and widespread families, showed no detectable impacts on a range of vegetative growth characteristics. Application of 1.0% foam to heathland soils showed no detectable impacts on soil invertebrate Orders sampled over several months. The results are encouraging for the continued use of Class A foam as a fire suppression technique.