Symptomatology and range of the blood disease bacterium A2 HR MARDI strain (Ralstonia syzygii subsp. celebensis) on selected hosts

Bacterial wilt disease is one of the major diseases in banana. In Malaysia, banana blood disease (BBD) is caused by the blood disease bacterium (BDB) A2 HR MARDI (Ralstonia syzygii subsp. celebensis). This disease bears similarities in symptomatology with Moko disease which caused by Ralstonia solanacearum and BBD in Indonesia, which caused by BDB R229. To determine the symptoms and host range of BDB, a pathogenicity test and host range study were carried out. In this study, there are four stages of external and internal symptoms which were observed. The pathogenicity of the bacterium cultures was then tested on banana, tomato and heliconia plantlets to determine the host range for BDB. To reconfirm that the banana was infected with BDB, re-isolation of BDB from the infected banana plants and Koch’s postulates test were performed. The results showed that there were symptoms of wilting and yellowing of leaves, which eventually caused plants death in the banana plantlets but no symptoms appeared in tomato and heliconia. The results indicate that BDB A2 HR MARDI is host-specific pathogen, only infecting banana similar to BDB R229 and is not as a broad range pathogen as R. solanacearum

Fractional boundary value problems: Analysis and numerical methods

This is the author's PDF of an article published in Fractional calculus and applied analysis 2011. The original publication is available at www.springerlink.comThis journal article discusses nonlinear boundary value problems.Fundacao para a Ciencia e Tecnologi

Assessment of selected herbicides and chelating agents in water using gas chromatography-electron capture detector (GC-ECD)

Water contamination by herbicides and chelating agents is increasing mainly due to the increasing agricultural activities. Water contamination by these compounds has become a concern due to their adverse effects to the environment and humans. Seven sampling sites of water sources in Selangor and Johor were chosen for the study. Contamination level of Mecoprop (MCCP), Nitrilotriacetic acid (NTA) and Ethylenediaminetetraacetic acid (EDTA) in these water body areas was determined by using Gas Chromatography-Electron Capture Detector (GC-ECD). Our results indicated that water samples of Sungai Melot in Selangor showed the highest presence of EDTA. MCCP was detected at a high level at Sungai Sarang Buaya, Johor while NTA showed similar level of concentration at three different sites, Ladang 10, Ladang Sayur and Mardi, Selangor

Potential of plant's Bowman-Birk protease inhibitor in combating abiotic stresses: a mini review

Bowman-Birk Inhibitor (BBI) is one of the subfamilies of serine protease inhibitors. Numerous studies have shown that in plants, BBI functions as part of their defense mechanism against pathogens and microorganisms. The BBI is also known to have anti-carcinogenic properties. Furthermore, the BBI has been reported to function in controlling abiotic stresses such as salinity and drought stresses. Abiotic stresses are the major problems in agricultural industry. Therefore, numerous researches have been carried out to characterize the BBI and to determine its roles during biotic and abiotic stresses. This paper presents a review regarding the relationship between Bowman-Birk inhibitor and the plant defensive mechanism against abiotic stresses

Alternative strategy in crop protection: protease inhibitors from turmeric

In an effort to meet the increasing demand for food arising from the growing human population, it is important to ensure food security by maintaining the continual supply of crop products and increase their productions. However, crops plantations are often challenged by the presences of pest insects and pathogens that could inflict diseases or feed on the crop plants and lead to massive losses in the crop productions. While chemical pesticides are commonly employed to control pest insects and pathogens problems, it is often associated with numerous negative side effects and excessive usage would cause lasting detrimental effects to the environments and consumers. Alternatively, crop plants with improved traits were produced through the application of biotechnology techniques to provide phytoprotection against pest insects and pathogens. Genes that encode for natural plant defence products, such as protease inhibitors, are genetically engineered into the crop plants and it is reported to be effectively showing insecticidal and anti-pathogenic properties. For this purpose, it is crucial to constantly discover uncharacterized protease inhibitors from novel sources as candidate for phytoprotection as this helps to overcome the adaptation and resistance buildup by the pest insects and pathogens. Turmeric plant is a well-known herbal plant commonly used as traditional medicine and it acts as a suitable novel source for discovery of protease inhibitors. As turmeric’s secondary metabolites are reported to exhibit a wide range of medicinal properties, it could be contributed by protease inhibitors which possessed high anti-pathogenic and inhibitory properties

RNA-sequencing of methyl-jasmonate treated turmeric (Curcuma longa) reveals novel protease inhibitor transcripts

Turmeric (Curcuma longa) has long been known in Southeast Asia as a medicinal plant and been used as folk remedies to treat minor illnesses like diarrhea or skin diseases. Recent studies on turmeric have shown numerous pharmacological properties such as anti-oxidant, anti-inflammatory, anti-pathogenic including anti-viral protease activities. All these beneficial properties make turmeric a suitable candidate for the discovery of novel protease inhibitors (PIs). PIs are commonly found in all organisms to regulate biological processes. In plant, PIs are reported to play important roles in plant defense mechanism. A number of these PIs have been genetically engineered into crop plants to enhance protection against microorganism and pest insects. However over time, the pathogens and pest insects are slowly adapting to the current strategies and overcome the additional defense barrier. Hence, this study was conducted to identify novel PIs genes from methyl jasmonate (MeJA)-treated turmeric plants through the whole transcriptome sequencing approach. From the raw data reads obtained from the RNA-sequencing of MeJA-treated leaf tissues, a single reference transcriptome was assembled de novo using Trinity software. A total of 105,529 contiguous sequences were obtained. Sequence annotation and homology search were performed onto several protein databases such as Uniprot, Pfam, GO and KEGG which resulted in around 50% of the transcripts showed similarity hits to known proteins. The individual expression profile of the transcripts from the control and MeJA-treated turmeric samples were generated and compared in order to identify differential expressed genes. A total of 4274 transcripts had been identified to be differentially expressed where there were 1599 upregulated transcripts and 2715 downregulated transcripts. A total of 21 transcripts showed sequence similarity hits to PIs families and three of the transcripts were identified to be upregulated from the MeJA treatment. These identified PIs transcript can serve as candidate genes for further functional studies and applications

Heterologous Expression of a Membrane-Spanning Auxin Importer: Implications for Functional Analyses of Auxin Transporters

Biochemical studies of plant auxin transporters in vivo are made difficult by the presence of multiple auxin transporters and auxin-interacting proteins. Furthermore, the expression level of most such transporters in plants is likely to be too low for purification and downstream functional analysis. Heterologous expression systems should address both of these issues. We have examined a number of such systems for their efficiency in expressing AUX1 from Arabidopsis thaliana. We find that a eukaryotic system based upon infection of insect cells with recombinant baculovirus provides a high level, easily scalable expression system capable of delivering a functional assay for AUX1. Furthermore, a transient transfection system in mammalian cells enables localization of AUX1 and AUX1-mediated transport of auxin to be investigated. In contrast, we were unable to utilise P. pastoris or L. lactis expression systems to reliably express AUX1

MODEL OF TEACHING MALAY LANGUAGE TO NON-NATIVE AND FOREIGN SPEAKER

Purpose – This study aims to develop a teaching model of the Malay language for non-native and foreign speakers in schools. Implementing this model can assist educators in teaching the Malay language to students who do not use it as their first language in everyday use. Methodology – This study used a qualitative approach to develop teaching models for non-native and foreign Malay speakers. Interviews were conducted with 27 teachers and 23 stakeholders who are experts in teaching the Malay language, especially in teaching non-native speakers. A prototype model was developed thematically as a result of interviews using ATLAS.ti 22. Further, the prototype model was used by ten teachers from primary, secondary, and international schools in their teaching. Findings – This study has succeeded in developing a model for teaching the Malay language to non-native speakers and foreigners that includes five elements: teaching strategies, individual differences, input, social, and motivation. This model strongly emphasises instruction involving interaction, communication, and bilateral relations as a medium for students’ language acquisition and meaningful input. Verbal interaction between teachers and students can stimulate and improve students’ language skills in learning Malay. Significance – This model can help teachers teach the Malay language to non-native speakers and foreigners with a greater focus on achieving learning objectives. This model is expected to expand the usage, cultivate interest, and facilitate teaching the Malay language in educational institutions

Kesan penuaan sesuhu terhadap sifat mikro kekerasan pempaterian Sn-Ag-Cu/CNT/Cu menggunakan pelekukan nano

Kesan penuaan terma terhadap sifat kekerasan sambungan pateri Sn-3.0Ag-0.5Cu (SAC305) yang ditambah dengan partikel karbon tiub nano (CNT) telah dikaji. Sifat kekerasan yang menggambarkan kekuatan sambungan pateri ditentukan melalui pendekatan pelekukan nano. Bahan pateri SAC ditambah dengan 0.03% kandungan berat CNT untuk menghasilkan bahan pes pateri SAC-CNT. Pes pateri yang telah dicetak di atas papan litar bercetak (PCB) berkemasan kuprum (Cu) dikenakan pematerian aliran semula pada suhu puncak 260°C untuk menghasilkan sambungan pateri SAC dan SAC-CNT. Sambungan pateri SAC dan SAC-CNT kemudiannya dikenakan penuaan terma melalui ujian penyimpanan suhu tinggi (HTS) selama 200, 400, 600, 800 dan 1000 j pada suhu tetap iaitu 150°C. Sampel sambungan pateri selepas pematerian dan penuaan terma dianalisis melalui kaedah pelekukan nano untuk menentukan sifat kekerasannya. Untuk analisis mikrostruktur, sampel dipunar dan imej dicerap melalui mikroskop optik. Keputusan menunjukkan nilai kekerasan menurun dengan peningkatan masa penuaan bagi kedua-dua sambungan pateri yang dikaji. Walau bagaimanapun, sambungan pateri SAC-CNT mempunyai kekerasan yang lebih tinggi iaitu sebanyak 10-26% berbanding sambungan pateri SAC. Melalui ujian pelekukan nano, sifat mikro kekerasan bagi sambungan pateri akibat tindakan penuaan terma sesuhu yang bersifat setempat dapat ditentukan. Corak nilai mikro kekerasan yang diperoleh adalah selari dengan corak yang diperoleh menggunakan kaedah ujian kekerasan konvensional