Use of reverse transcription-polymerase chain reaction (RT-PCR) for Cymbidium mosaic virus (CyMV) detection in orchids

The reverse transcription-polymerase chain reaction CRT-PCR) was adapted for detection of Cymbidium mosaic virus CCyMV) in orchids. The oligonucleotide primers used were selected from the predicted homologous coat protein region of CyMV and other Potexviruses which enabled to amplify approximately 313 bp and 227 bp fragments using optimum reaction conditions of 2.5 mM MgCh and 30 cycles of amplification. The RT-PCR allowed the detection of CyMV RNA and virion in purified fonns as well as in crude tissue extracts of orchid. Direct CyMV RNA detection was possible in leaves, shoots, stems, roots and petals. The detection limits of RNA in purified CyMV and virion by RT-PCR described were 10 ng and 2 ng, respectively. The PCR amplified fragments were confinned to be CyMV-specific by dotblot hybridization with DIG-labelled CyMV cDNA probe. The suitability of the RT-PCR in routine testing of CyMV was detennined and compared with those of DAS-ELISA. Thirty samples of leaf tissues representing various genera or hybrids of cultivated local orchid from glasshouse and commercial nurseries were tested for CyMV by RT-PCR and DAS-ELISA. Among 15 samples that tested positive for CyMV infection by DAS-ELISA, only 7 samples gave the expected amplification fragments when subjected in RTPCR assays. The equal detection limit on purified CyMV virion by RT-PCR and DAS-ELISA and lower sensitivity of RT-PCR in detecting CyMV in a field indexing trial suggested that RT-PCR is unsuitable to replace DAS-ELISA for routine testing of CyMV in local orchids

Fuzzy Delphi method for evaluating HyTEE model (hybrid software change management tool with test effort estimation)

When changes are made to a software system during development and maintenance, they need to be tested again i.e. regression test to ensure that changes behave as intended and have not impacted the software quality. This research will produce an automated tool that can help the software manager or a maintainer to search for the coverage artifact before and after a change request. Software quality engineer can determine the test coverage from new changes which can support cost estimation, effort, and schedule estimation. Therefore, this study is intended to look at the views and consensus of the experts on the elements in the proposed model by benefitting the Fuzzy Delphi Method. Through purposive sampling, a total of 12 experts from academic and industrial have participated in the verification of items through 5-point linguistic scales of the questionnaire instrument. Outcome studies show 90% of elements in the proposed model consists of change management, traceability support, test effort estimation support, regression testing support, report and GUI meet, the value threshold (d construct) is less than 0.2 and the percentage of the expert group is above 75%. It is shown that elements of all the items contained in the venue are needed in the HyTEE Model (Hybrid Software Change Management Tool with Test Effort Estimation) based on the consensus of experts

Role of Supply Chain Management on the Job Control and Social Support for Relationship between Work-Family Conflict and Job Satisfaction

Abstract- The present study investigates the relationship between work-family conflict and job satisfaction of Malaysian workers (N = 1125) based on the supply chain management. It examines the direct and moderating effects of job control and social support on work-family conflict and job satisfaction relationship. The current study examines the Job Demand-Control (JDC) [1] and Job Demand-Control-Support (JDCS) [2] models which are under research in the work-family conflict. Hierarchical regression analyses in the study reveal that work to family conflict (WFC), family to work conflict (FWC) and social support have a direct effect on job satisfaction. However, the result reveals that employees’ job control was not the primary predictor of their job satisfaction. Contrary to the prediction of the JDCS model, the moderating effects of job control and social support on the relationship between work-family conflict and job satisfaction are not found. Implications regarding the importance of the main effect of social support and supply chain management on understanding job satisfaction in Malaysian society and other possible moderators are discussed

Immunosensor development for rice tungro bacilliform virus (RTBV) detection using antibody nano-gold conjugate

Rice tungro disease (RTD) causes major losses to rice crop plantation. Hence, a highly sensitive tools need to be developed for the detection of RTD which can be employed in both laboratory and field. An electrochemical immunosensor system for the detection of RTD, based on immobilized specific antibodies conjugated with gold nanoparticle was developed for this purpose. However, this paper focus for RTBV interaction using the conjugated antibodies which is added with polymer and deposited on carbon screen printed working electrodes

Characterisation of cucumber mosaic virus (CMV) in Catharanthus roseus (L.)G. don and its effects on anticancer metabolite production

Natural virus-like disease symptoms such as mosaic and deformation of the leaves and flowers of malformed shape or slight colour-breaking of the petals were observed on Catharanthus roseus plants in Serdang, Selangor, Malaysia. Double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) detected cucumber mosaic virus (CMV) in high concentrations in the leaf extract of naturally-infected C. roseus as well as in the leaf extract of inoculated C. roseus. The purified virions were isometric particles with mean diameter 28.60 ± 0.48 nm and contained a central core. The virus induced systemic leaf mosaic on N. tabacum cv. White Burley, C. sativus, N. benthamiana and N. glutinosa. Local lesions and brown necrotic local lesions were produced on the inoculated leaves of C. amaranticolor and V.sesquipedalis, respectively. A 1000 bp DNA fragment covering the entire coat protein (CP) region of the purified virus was amplified using the primers CMVF1(5’-TAGACAT/ACTGTGACGCGA-3’) and CMVR2 (5’-GTAAGCTGGATGGACAAC-3’). The sequence obtained (GenBank accession number EU726631) revealed a 100% nucleotide and amino acid identities to a CP gene of CMV isolated from C. roseus in India (GenBank accession number EU310928) which is a member of subgroup 1B. Cytopathological study showed that CMV infection disrupted the chloroplast ultrastructure in the C. roseus leaf cells. The presence of large starch grains in the surrounding necrotic zones caused disintegration of the stromatic lamellae and grana, changing the chloroplasts symmetry. Complex membranous structures in the cells vacuoles and phytoferritin macromolecules in the chloroplast stroma were also observed in the leaf cells of CMV-infected C. roseus. Chloroplast was also the most altered organelle following CMV infection in the leaf cells of N. tabacum cv. White Burley, C. sativus and C. amaranticolor. A comparative HPLC analysis on the yields of two anticancer metabolites, vincristine and vinblastine in the C. roseus leaf,stem and root tissues at different growing stages indicated that CMV infection modified the metabolism of the metabolites. Following CMV infection, the peak production period of vincristine and vinblastine in leaves was delayed from four months old uninfected C. roseus plants to six months old CMV-infected plants. CMV infection also delayed the peak production period of vincristine in roots from five months old uninfected plants to seven months old infected ones. As for vinblastine, the peak production period was delayed from five months old uninfected plants to eight months old infected plants. Another remarkable alteration after CMV infection is that significant increases in the contents of vincristine in the infected root tissues, particularly at six to nine months old. The concentration of vinblastine which increased about two, four and seven-folds in the roots of six, seven and eight months old CMV-infected plants, respectively, could be another interesting finding of CMV modification, particularly in these anticancer compounds biosynthesis pathway in C. roseus plants

INCREASING YIELD OF SUSCEPTIBLE AND RESISTANT RICE BLAST CULTIVARS USING SILICON FERTILIZATION

Rice blast is one of the most critical limiting factors for rice plant growth performance. Silicon has been shown to have positive effects in controlling several plant diseases. The study aimed to investigate the impact of silicon levels on rice yield, silicon content, and panicle blast in rice plants. The study was set up as a 2 x 5 factorial experiment with three replications and arranged in a randomized complete block design. The first factors were two rice cultivars, MARDI Siraj 297 (resistant) and MR 263 (susceptible). The second factors were five levels of calcium silicate (0 g, 4 g, 8 g, 12 g, and 16 g) applied to 40 kg soil per pot. The standard fertilizers, i.e., N, P2 O5, and K2 O, were applied four times at the recommended dosage. High virulent of Pyricularia oryzae conidia (4 x 104 conidia ml-1) was sprayed using a hand sprayer (30 ml pot-1) at the time of fully completed panicle development (65 days after planting). Observed parameters were plant growth (height and culm length), yields (spikelets per panicle, grain filling percentage, and harvest index), panicle blast severity, and silica content in leaf, stem, and panicle. The results showed that silicon application reduced panicle blast severity, leading to higher yield per plant. The increase of the rice yield was a result of a significant increae in panicle per m2 , spikelet per m2 , and percentage of filled grain. Panicle blast greatly affected the performance of spikelet number per m2 , percentage of filled grain, grain weight, and yield per plant for the susceptible cultivar. Application of calcium silicate 10 g 40 kg-1 soil per pot at panicle initiation is recommended to reduce panicle blast severity hereby improve grain yield

A review for improving software change using traceability model with test effort estimation

Maintaining a software system includes tasks such as fixing defects, adding new features, or modifying the software (software changes) to accommodate different environments. Then, the modified software system needs to be tested, to ensure the changes will not having any adverse effects on the previously validated code. Regression testing is one of the approaches which software tester used to test the software system. The traditional regression testing strategy was to repeat all the previous tests and retesting all the features of the program even for small modifications. For programming with thousand lines of codes (LOC), the cost of retesting the entire system is expensive if attempted after every change. This practice is becoming increasingly difficult because of the demand for testing the new functionalities and correcting errors with limited resources. Numerous techniques and tools have been proposed and developed to reduce the costs of regression testing and to aid regression testing processes, such as test suite reduction, test case prioritization, and test case done on the thresholds and weightings used in regression testing. However, there is still need to study on the software traceability model of coverage analysis in software changes during regression testing and test effort estimation on regression testing. Hence, this paper describes the proposal for improving software changes with hybrid traceability model and test effort estimation during regression testing. We will explain our proposed work including the problem background, the intended research objectives, literature review and plan for future implementation. This study is expected to contribute in developing hybrid traceability model for large software development project to support software changes during regression testing with test estimation approach and expected to reduce operational cost during the implementation on software maintenance. Also, it is hoped that an efficient and improve solution to regression testing can be realized, thus, gives the benefits to software testers and project manager manage the software maintenance task since it is a critical part in software project development

The effect and possible mitigation of UV radiation on baculoviruses as bioinsecticides

The effect and possible mitigation of UV radiation on baculoviruses as bioinsecticides. Biodiversitas 23: 3721-3735. Indiscriminate use of pesticides has raised concerns over environmental and human health issues. A more environmentally-friendly biological approach to control insect pests is gaining importance. For decades, bioinsecticides based on viruses have been used to protect crops and forests. The viruses belonging to the Baculoviridae family are known to infect insect pests, and hence can be used as biopesticides. Baculoviruses are mostly specific to the host and are not lethal to the non-target organism. However, their usage is limited for field application due to a slow kill speed and sensitivity towards UV irradiation. This review paper discusses the life cycle of baculoviruses, their mode of infection and transmission as well as the influence of UV radiation on the effectiveness of baculoviral insecticides for field application

Variants in the mitochondrial genome sequence of Oryctes rhinoceros (Coleoptera: Scarabaeidae) infected with Oryctes rhinoceros nudivirus in oil palm and coconut plantations

Abstract The CRB (coconut rhinoceros beetle) haplotype was classified into CRB-S and CRB-G, based on the presence of single nucleotide polymorphisms (SNPs) in the mitochondrial cox1 gene. Mitochondrial genomes (mitogenomes) are the most widely used genetic resources for molecular evolution, phylogenetics, and population genetics in relation to insects. This study presents the mitogenome CRB-G and CRB-S which were collected in Johor, Malaysia. The mitogenome of CRB-G collected from oil palm plantations in 2020 and 2021, and wild coconut palms in 2021 was 15,315 bp, 15,475 bp, and 17,275 bp, respectively. The CRB-S was discovered in coconut and oil palms in 2021, and its mitogenome was 15,484 bp and 17,142 bp, respectively. All the mitogenomes have 37 genes with more than 99% nucleotide sequence homology, except the CRB-G haplotype collected from oil palm in 2021 with 89.24% nucleotide sequence homology. The mitogenome of Johor CRBs was variable in the natural population due to its elevated mutation rate. Substitutions and indels in cox1, cox2, nad2 and atp6 genes were able to distinguish the Johor CRBs into two haplotypes. The mitogenome data generated in the present study may provide baseline information to study the infection and relationship between the two haplotypes of Johor CRB and OrNV in the field. This study is the first report on the mitogenomes of mixed haplotypes of CRB in the field