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Fulltext Chitosan Nanoparticles as Carriers for the Delivery of ΦKAZ14 Bacteriophage for Oral Biological Control of Colibacillosis in Chickens

Adamu Ahmad K, Sabo Mohammed A, Abas F

Molecules, 2016 Mar 14;21(3):256.
PMID: 26985885 DOI: 10.3390/molecules21030256

The use of chitosan as a delivery carrier has attracted much attention in recent years. In this study, chitosan nanoparticles (CS-NP) and chitosan-ΦKAZ14 bacteriophage-loaded nanoparticles (C-ΦKAZ14 NP) were prepared by a simple coercavation method and characterized. The objective was to achieve an effective protection of bacteriophage from gastric acids and enzymes in the chicken gastrointestinal tract. The average particle sizes for CS-NP and C-ΦKAZ14 NP were 188 ± 7.4 and 176 ± 3.2 nm, respectively. The zeta potentials for CS-NP and C-ΦKAZ14 NP were 50 and 60 mV, respectively. Differential scanning calorimetry (DSC) of C-ΦKAZ14 NP gave an onset temperature of -17.17 °C with a peak at 17.32 °C and final end set of 17.41 °C, while blank chitosan NP had an onset of -20.00 °C with a peak at -19.78 °C and final end set at -20.47. FT-IR spectroscopy data of both CS-NP and C-ΦKAZ14 NP were the same. Chitosan nanoparticles showed considerable protection of ΦKAZ14 bacteriophage against degradation by enzymes as evidenced in gel electrophoresis, whereby ΦKAZ14 bacteriophage encapsulated in chitosan nanoparticles were protected whereas the naked ΦKAZ14 bacteriophage were degraded. C-ΦKAZ14 NP was non-toxic as shown by a chorioallantoic membrane (CAM) toxicity assay. It was concluded that chitosan nanoparticles could be a potent carrier of ΦKAZ14 bacteriophage for oral therapy against colibacillosis in poultry.
Arabic phoneme-grapheme correspondence by non-native, deaf children with cochlear implants and normal hearing children

Anis FN, Umat C, Ahmad K, Abdul Hamid B

Cochlear Implants Int, 2022 Nov;23(6):347-357.
PMID: 36005236 DOI: 10.1080/14670100.2022.2114583

OBJECTIVE: This study aimed to compare the error patterns of Arabic phoneme-grapheme correspondence by a group of Malay children with cochlear implants (CIs) and normal hearing (NH) and the effects of the visual graphical features of Arabic graphemes (no-dot, single-dot, and multiple-dots) on the phoneme-grapheme correspondence.
METHODS: Participants were matched for hearing age (Mean, M = 7 ± 1.03 years) and duration of exposure to Arabic sounds (M = 2.7 ± 1.2 years). All 28 Arabic phonemes were presented through a loudspeaker and participants pointed to the graphemes associated with the presented phonemes.
RESULTS: A total of 336 and 616 tokens were collected for six children with CI and 11 NH children for each task, i.e., phonemes repetition and phoneme-grapheme correspondence. Both groups found it easier to repeat phonemes than the phoneme-grapheme correspondence. The children with CIs showed more confusion ([ظ, ز, ذ, ض, خ, ب, ه, س, ع, & ث] >10% correct scores) in phoneme-grapheme correspondence than the NH children ([ظ:14%] and [ث: 27%]). There was a significant interaction (p = 0.001) among the three visual graphical features and hearing status (CI and NH).
CONCLUSION: Our results infer that non-native Malay children with CIs and NH use different strategies to process the Arabic graphemes' visual features for phoneme-grapheme correspondence.
Early Detection of Ganoderma Basal Stem Rot of Oil Palms Using Artificial Neural Network Spectral Analysis

Ahmadi P, Muharam FM, Ahmad K, Mansor S, Abu Seman I

Plant Dis, 2017 Jun;101(6):1009-1016.
PMID: 30682927 DOI: 10.1094/PDIS-12-16-1699-RE

Ganoderma boninense is a causal agent of basal stem rot (BSR) and is responsible for a significant portion of oil palm (Elaeis guineensis) losses, which can reach US$500 million a year in Southeast Asia. At the early stage of this disease, infected palms are symptomless, which imposes difficulties in detecting the disease. In spite of the availability of tissue and DNA sampling techniques, there is a particular need for replacing costly field data collection methods for detecting Ganoderma in its early stage with a technique derived from spectroscopic and imagery data. Therefore, this study was carried out to apply the artificial neural network (ANN) analysis technique for discriminating and classifying fungal infections in oil palm trees at an early stage using raw, first, and second derivative spectroradiometer datasets. These were acquired from 1,016 spectral signatures of foliar samples in four disease levels (T1: healthy, T2: mildly-infected, T3: moderately infected, and T4: severely infected). Most of the satisfactory results occurred in the visible range, especially in the green wavelength. The healthy oil palms and those which were infected by Ganoderma at an early stage (T2) were classified satisfactorily with an accuracy of 83.3%, and 100.0% in 540 to 550 nm, respectively, by ANN using first derivative spectral data. The results further indicated that the sensitive frond number modeled by ANN provided the highest accuracy of 100.0% for frond number 9 compared with frond 17. This study showed evidence that employment of ANN can predict the early infection of BSR disease on oil palm with a high degree of accuracy.
Understanding the Perception of Islamic Medicine Among the Malaysian Muslim Community

Ahmad K, Ariffin MFM, Deraman F, Ariffin S, Abdullah M, Razzak MMA, et al.

J Relig Health, 2018 Oct;57(5):1649-1663.
PMID: 29075949 DOI: 10.1007/s10943-017-0507-9

This study was conducted to identify and describe the patients' perceptions of Islamic medicine based on gender, age, marital, educational level and working status among the Malaysian Muslim population. A nationwide interviewer-administered questionnaire survey was conducted in 2013. An open-ended questionnaire pertaining to Islamic medicine was used to increase the probability of capturing maximum data. This survey implemented a multistage design, stratified by state, proportionate to the size of the state population and was representative of the Malaysian population. Post-survey classification of results was performed accordingly. Complex data analysis was carried out using SPSS 16.0. The discussion was identified and categorised into various sections. The paper concludes that Islamic medicine has a major influence in the Malaysian Muslim community compared to other alternatives. Further, its potential for growth and importance especially for treating spiritual ailments cannot be denied. The respondents indicated that two factors motivate Islamic medicine in Malaysia: (1) the Muslim community opts for alternative healing because of their dissatisfaction with conventional methods; (2) Islamic medicine focuses only on healing spiritual-related problems. The average perception of respondents is that the function of Islamic medicine in healing physical diseases is undervalued and that it is not suitable to replace the functions of modern health institutions.
Discharging patients: A perspective from speech-language pathologists working in public hospitals in Malaysia

Ahmad K

Int J Speech Lang Pathol, 2010 Aug;12(4):317-9; discussion 329-32.
PMID: 20590514 DOI: 10.3109/17549507.2010.483017

Speech-language pathologists (SLPs) practising in Malaysia face similar dilemmas as their counterparts in more developed countries when it comes to deciding on discharge/termination of services for their patients. Furthermore, discharge dilemmas appear to be a frequent and inevitable part of their everyday practice. In an interview conducted for the purpose of this paper, it was clear that many SLPs found it difficult to articulate or justify the process they took to reach a decision on whether or not to terminate their services or discharge their patients. Much of the difficulty is anchored on the need to be realistic and function within the confines of limited resources. Malaysian SLPs were aware of the ideals that had to be abandoned along the way but had not allowed guilt to dissuade or discourage them from providing what they perceived as the next best available service. The not-so ideal decisions made by these SLPs may be frowned upon by international standards but must be examined within the local historical perspective of the development of the SLP profession in Malaysia. The dilemma will continue until the country produces SLPs in sufficient numbers but the profession is reminded that less-than-ideal practices may perpetuate over time into unhealthy traditions that will require major efforts to be undone.
Electrokinetic Behavior of Palm Oil Emulsions in Dilute Electrolyte Solutions

Ho CC, Ahmad K

J Colloid Interface Sci, 1999 Aug 1;216(1):25-33.
PMID: 10395758

The effect of metal cations, both nonhydrolyzable and hydrolyzable, on the zeta potential of palm olein emulsions stabilized by the nonionic emulsifier, polyoxyethylene nonyl phenyl ether, was investigated as a function of pH and cation concentrations, respectively. The oil drops were found to be negatively charged in the presence of simple mono- and divalent cations. Charge reversal of the oil drops was observed when hydrolyzable cations (Zn2+, Cu2+, Fe3+, and Al3+) were used and the behavior is strongly dependent on the type of cation, its concentration, and the pH of the dispersion. The results are discussed in terms of current theories of electrophoresis and adsorption-precipitation at interfaces. The chemical free energies of adsorption of the cations were calculated. Copyright 1999 Academic Press.
Malaysia culls pigs as Nipah virus strikes again

Ahmad K

Lancet, 2000 Jul 15;356(9225):230.
PMID: 10963210
Fulltext Foreign bodies in the laryngotracheobronchial tree

Razi Hadi A, Said H, Ahmad K

Med J Malaysia, 1988 Mar;43(1):74-83.
PMID: 3244325

Foreign bodies in the laryngotracheobronchial tree are not uncommon. Their clinical presentations, the radiological and endoscopic findings in sixteen cases that presented to the Department of Otorhinolaryngology, Universiti Kebangsaan Malaysia were reviewed. The technique of removal is also discussed.
Study site: Hospital Kuala Lumpur, Malaysia (UKM unit)
Fulltext Current strategies and perspectives in detection and control of basal stem rot of oil palm

Siddiqui Y, Surendran A, Paterson RRM, Ali A, Ahmad K

Saudi J Biol Sci, 2021 May;28(5):2840-2849.
PMID: 34012325 DOI: 10.1016/j.sjbs.2021.02.016

The rapid expansion of oil palm (OP) has led to its emergence as a commodity of strategic global importance. Palm oil is used extensively in food and as a precursor for biodiesel. The oil generates export earnings and bolsters the economy of many countries, particularly Indonesia and Malaysia. However, oil palms are prone to basal stem rot (BSR) caused by Ganoderma boninense which is the most threatening disease of OP. The current control measures for BSR management including cultural practices, mechanical and chemical treatment have not proved satisfactory. Alternative control measures to overcome the G. boninense problem are focused on the use of biological control agents and many potential bioagents were identified with little proven practical application. Planting OP varieties resistant to G. boninense could provide the ideal long-term solution to basal stem rot. The total resistance of palms to G. boninense has not yet been reported, and few examples of partial resistances have been observed. Importantly, basidiospores are now recognized as the method by which the disease is spread, and control methods require to be revaluated because of this phenomenon. Many methods developed to prevent the spread of the disease effectively are only tested at nursery levels and are only reported in national journals inhibiting the development of useful techniques globally. The initial procedures employed by the fungus to infect the OP require consideration in terms of the physiology of the growth of the fungus and its possible control. This review assesses critically the progress that has been made in BSR development and management in OP.
Prevalence of Fusarium Wilt Disease of Cucumber (Cucumis sativus Linn) in Peninsular Malaysia Caused by Fusarium oxysporum and F. solani

Din HM, Rashed O, Ahmad K

Trop Life Sci Res, 2020 Oct;31(3):29-45.
PMID: 33214854 DOI: 10.21315/tlsr2020.31.3.3

Fusarium wilt disease is one of the most problematic and destructive disease in cucumber production. The causative agents are Fusarium oxysporum and F. solani. These pathogens are soil borne and transmitted through infested soil and water. A field survey was conducted to study the disease prevalence in the major growing areas of cucumber in Peninsular Malaysia. Field study revealed that the disease was highly prevalence in the field with the disease incidence was in the range of 10%-60%. The morphological properties of F. oxysporum are microconidia (3.8-15.7 μm × 2.9-4.9 μm), macroconidia (14.8-38.5 μm × 2.4-5.7 μm) and number of septate was 1-4. While for F. solani are microconidia (3.39-14.63 μm × 2.36-4.44 μm), macroconidia (7.22-50.46 μm × 2.43-6.14 μm) and number of septate was 1-5. Based on molecular identification had confirmed that the disease is caused by F. oxysporum and F. solani with similarity index of 99%-100% based on internal transcribed spacer (ITS) gene sequences. The pathogenicity test showed that the symptoms of Fusarium wilt disease was firstly appeared as yellowing of old leaves. Progressively, the infected plant will be wilted and finally died. The outputs of this study are highly important to establish an effective disease management programme to reduce disease prevalence and yield loss in the field.
Phytobezoar: a case report

Chellappa M, Ahmad K

Med J Malaysia, 1978 Mar;32(3):245-6.
PMID: 683051
Fulltext Kaempferol ameliorates palmitate-induced lipid accumulation in HepG2 cells through activation of the Nrf2 signaling pathway

Zhao L, Yang L, Ahmad K

Hum Exp Toxicol, 2023;42:9603271221146780.
PMID: 36607234 DOI: 10.1177/09603271221146780

OBJECTIVES: Kaempferol (KMF), has beneficial effects against hepatic lipid accumulation. In this study, we aimed to investigate molecular mechanism underlying the protective effect of KMF on lipid accumulation.
METHODS: HepG2 cells were treated with different concentrations of KMF and 0.5 mM palmitate (PA) for 24 h. The mRNA and protein levels of genes involved in lipid metabolism were evaluated using real-time PCR and western blot. The expression of Nrf2 was silenced using siRNA.
RESULTS: Data indicated that KMF (20 μM) reversed PA-induced increased triglyceride (TG) levels and total lipid content. These effects were accompanied by down-regulation of the mRNA and protein levels of lipogenic genes (FAS, ACC and SREBP1), and up-regulation of genes related to fatty acid oxidation (CPT-1, HADHα and PPARα). Kaempferol significantly decreased the levels of the oxidative stress markers (ROS and MDA) and enhanced the activities of antioxidant enzymes SOD and GPx in PA-challenged cells. Luciferase analysis showed that KMF increased the transactivation of Nrf2 in hepatocytes. The results also revealed that KMF-mediated activation of Nrf2 target genes was suppressed by Nrf2 siRNA. Furthermore, Nrf2 siRNA abolished the KMF-induced reduction in ROS and MDA levels in PA treated cells. In addition, the inhibitory effect of KMF on TG levels and the mRNA and protein levels of FAS, ACC and SREPB-1 were significantly abolished by Nrf2 inhibition. Nrf2 inhibition also suppressed the KMF-induced activation of genes involved in β oxidation (CPT-1 and PPAR-α).
CONCLUSION: The results suggest that KMF protects HepG2 cells from PA-induced lipid accumulation via activation of the Nrf2 signaling pathway.
Zingiber officinale Roscoe Essential Oils-Loaded Chitosan Nanoparticles with Enhanced Bactericidal Efficacy against Burkholderia glumae in Rice

Tiran Gunasena M, Hussein MZ, Ali A, Wahab MAA, Bashir Kutawa A, Rafif A, et al.

Chem Biodivers, 2023 Dec;20(12):e202300686.
PMID: 37905394 DOI: 10.1002/cbdv.202300686

Ginger essential oils (GEO) shows exceptional antimicrobial properties against plant pathogens. Due to its high volatility and low stability, it requires encapsulation to retain its effective properties. The GEO-Chitosan (GEO-CS) nanobactericide was developed using the ionic gelation method. The nanobactericides show particle diameters of 465, 28, 35, 48 and 500 nm when sodium tripolyphosphate (TPP) concentrations used in the preparation were 0.0, 0.5, 1.0, 2.0 and 4.0 %, respectively. The X-ray diffraction and the UV-vis studies revealed that the GEO was encapsulated into the chitosan nanoparticles with an encapsulation efficiency of around 46 % and a loading capacity of 27-34 %. The antibacterial activity of GEO-chitosan nanobactericide against Burkholderia glumae (Bg) was found to be 7.5-11.8 mm, with minimum inhibitory concentration and minimum bactericidal concentration values of 15.6 μl/mL and 31.25 μl/mL, respectively. Hence, these findings indicate that the prepared GEO-CS nanobactericides were found to be effective against Bg. This preliminary study is toward the development of new agronanobactericides using a natural product to control Bg.
Fulltext Turbulence Model Selection for Low Reynolds Number Flows

Aftab SM, Mohd Rafie AS, Razak NA, Ahmad KA

PLoS One, 2016;11(4):e0153755.
PMID: 27104354 DOI: 10.1371/journal.pone.0153755

One of the major flow phenomena associated with low Reynolds number flow is the formation of separation bubbles on an airfoil's surface. NACA4415 airfoil is commonly used in wind turbines and UAV applications. The stall characteristics are gradual compared to thin airfoils. The primary criterion set for this work is the capture of laminar separation bubble. Flow is simulated for a Reynolds number of 120,000. The numerical analysis carried out shows the advantages and disadvantages of a few turbulence models. The turbulence models tested were: one equation Spallart Allmars (S-A), two equation SST K-ω, three equation Intermittency (γ) SST, k-kl-ω and finally, the four equation transition γ-Reθ SST. However, the variation in flow physics differs between these turbulence models. Procedure to establish the accuracy of the simulation, in accord with previous experimental results, has been discussed in detail.
Fulltext CFD study on NACA 4415 airfoil implementing spherical and sinusoidal Tubercle Leading Edge

Aftab SMA, Ahmad KA

PLoS One, 2017;12(8):e0183456.
PMID: 28850622 DOI: 10.1371/journal.pone.0183456

The Humpback whale tubercles have been studied for more than a decade. Tubercle Leading Edge (TLE) effectively reduces the separation bubble size and helps in delaying stall. They are very effective in case of low Reynolds number flows. The current Computational Fluid Dynamics (CFD) study is on NACA 4415 airfoil, at a Reynolds number 120,000. Two TLE shapes are tested on NACA 4415 airfoil. The tubercle designs implemented on the airfoil are sinusoidal and spherical. A parametric study is also carried out considering three amplitudes (0.025c, 0.05c and 0.075c), the wavelength (0.25c) is fixed. Structured mesh is utilized to generate grid and Transition SST turbulence model is used to capture the flow physics. Results clearly show spherical tubercles outperform sinusoidal tubercles. Furthermore experimental study considering spherical TLE is carried out at Reynolds number 200,000. The experimental results show that spherical TLE improve performance compared to clean airfoil.
Fulltext A secure and dependable trust assessment (SDTS) scheme for industrial communication networks

Khan T, Singh K, Ahmad K, Ahmad KAB

Sci Rep, 2023 Feb 02;13(1):1910.
PMID: 36732583 DOI: 10.1038/s41598-023-28721-x

Due to tamper-resistant sensor nodes and wireless media, Industrial Wireless Sensor Networks (WSNs) are susceptible to various security threats that severely affect industrial/business applications. The survival of sensor networks is highly dependent on the flourishing collaboration of sensor nodes. Trust management schemes seem to be realistic and promising techniques to improve security as well as cooperation (dependability) among sensor nodes by estimating the trust level (score) of individual sensor nodes. This research paper presents a well-organized and motivating secure, dependable trust assessment (SDTS) scheme for industrial WSNs to cope with unexpected behavior such as an on-off attack, bad-mouthing attack, garnished attack, etc., by employing robust trust evaluation components based on success ratio and node misbehaviour. SDTS incorporates an interesting trust evaluation function in which the trust range can be adjusted in accordance with the application requirement. SDTS include direct communication trust, indirect communication trust, data trust, and misbehavior-based trust to defend the multiple internal attacks. SDTS works according to the behavior of nodes, i.e., whether the sensor nodes are interacting frequently or not. Moreover, abnormal attenuation and dynamic slide lengths are incorporated in the proposed model (SDTS) to deal with various natural calamities and internal attacks. SDTS is compared against three recent state-of-the-art methods and found efficient in terms of ease of trust assessment, false-positive rate (2.5%), false-negative rate (2%), attack detection rate (90%), detection accuracy (91%), average energy consumption (0.40 J), and throughput (108 Kbps) under the load of 500 sensor nodes with 50% malicious nodes. Investigational results exhibit the potency of the proposed scheme.
The prevalence of hypersensitivity reactions to snake antivenoms administered in sultanah nur zahirah hospital from 2013 to 2016

Nur AS, Hamid F, Mohd Shahezwan AW, Mohd Zaki FS, Ahmad KI

Med J Malaysia, 2020 05;75(3):216-220.
PMID: 32467535

INTRODUCTION: Snakebite is an important medical emergency. Antivenoms remain the only proven treatment for snake envenoming. However, the use of antivenom is associated with hypersensitivity reactions. The aims of this study were to determine the prevalence and types of hypersensitivity reactions and types and outcomes of pharmacological and non-pharmacological treatments for antivenom reactions among snakebite patients that received antivenoms.
METHODS: This was a 4-year cross-sectional study of snakebite patients from January 2013 to December 2016 in Hospital Sultanah Nur Zahirah (HSNZ), Terengganu. Data was extracted from the Pharmacy Record on the usage of antivenom and patients of snakebites treated with antivenom were identified. Data of patients were then obtained from the electronic medical records.' Demographic details, clinical features and characteristics of antivenom reactions of patients were recorded in standardized data collection forms and analyzed using chi-square or Mann- Whitney U tests.
RESULTS: Of the 44 patients who received antivenom, 24 (54.5%) developed hypersensitivity reaction. All patients developed reaction early. No patient developed delayed (serum-sickness) reaction. Of the 24 patients, 14 (58.3%) had moderate to severe hypersensitivity reaction and 9 (37.5%) patients had mild reactions. Only one (4.2%) patient presented with bradycardia.
CONCLUSION: The prevalence of early hypersensitivity reaction to snake antivenom in HSNZ was relatively high. Healthcare providers should be aware of the appropriate method of preparing and administering antivenom, and the management for acute hypersensitivity reactions. This will optimize the management of snakebite and ensure patient safety.
Fulltext Comet Lulin

Othman, M., Ahmad, K.

ASM Science Journal, 2008;2(2):183-183.
MyJurnal

Comet Lulin was discovered by Lin Chi-Sheng and Ye Quanzhi using the 16-inch telescope at Lulin Observatory in Nantou, Taiwan in 2007. According to Brian Marsden of the Smithsonian Astrophysical Observatory, it reached its perihelion on 10 January 2009 at a distance of 113 million
km from the Sun. It moves in a very nearly parabolic retrograde (‘backwards’ compared to the movement of the planets) orbit at an inclination of 1.6 degrees from the ecliptic (“Newfound Comet Lulin to Grace Night Skies”). http://www.space.com/spacewatch/090206-ns-cometlulin.html). It passed nearest to the Earth at a distance of 61 million km on 23 February 2009.
Fulltext Comet 17P/Holmes

Othman, M., Ahmad, K.

ASM Science Journal, 2007;1(2):181-182.
MyJurnal

Comet 17P/Holmes was discovered by Edwin Holmes on 6 November 1892 while he was conducting regular observations of the Andromeda Galaxy (M31). Calculations using observation of its orbits established the perihelion date as 13 June and the orbital period as 6.9 years. The 1899 and 1906 appearances were observed, but the comet was only seen again in 1964. The comet has since been
observed on every subsequent return.
Fulltext First report of postharvest stem end rot disease on MD2 pineapple fruits caused by Neoscytalidium dimidiatum in Malaysia

Kuruppu M, Siddiqui Y, Ahmad K, Ali A

Plant Dis, 2020 Dec 29.
PMID: 33373283 DOI: 10.1094/PDIS-10-20-2318-PDN

Repeated sampling conducted from December 2019 to March 2020, and fruit of pineapple (Ananas comosus) var MD2 showing early stem end rot symptoms including brown and rotten fruit skin near the stem end region (Fig.1Aa) or darker skin with black discoloration (Fig.1Ab) indicated a consistent fungal infection. The samples (30 fruits from each location) were collected from store houses in three farmer fields with 60% disease incidence in Serdang, (3.0220oN,101.7055oE), Selangor, West Malaysia. The pulp of infected fruits appeared watery with characteristic spoilage odour. Symptomatic necrotic tissues from stem end region and skin were cut in to pieces (1x1cm), surface sterilized and plated onto potato dextrose agar amended aseptically with 0.5 g L-1 streptomycin sulphate. The plates were incubated at room temperature (28±2oC) in natural light conditions. Five days old cultures were light grey in colour and gradually turned dark brown to black with dense deeply tufted, mycelium as the culture aged (Fig.1B, C). Conidial morphology was observed using compound microscope (Olympus model BX-50F4, Tokyo, Japan) equipped with Dino-Eye. Branched mycelia with 0-1 septate arthospores were evident in 14 days old cultures (Fig.1D). Measured arthroconidia (5 to10x3 to 4.5µm) were ellipsoid to ovoid or round shaped, hyaline with an acutely rounded apex, truncate base, initially aseptate (Fig.1E) and arranged as chain at maturity (Fig.1F). The pathogen was identified through PCR amplification of the internal transcribed spacer (ITS) region using ITS1 and ITS4 primers (White et al., 1990) and BLASTn homology search as Neoscytalidium dimidiatum based on 100% similarity to a reference sequence (accession number KJ648577) that was previously deposited (Mohd et al.,2013). The sequence was deposited in Gen Bank ( accession number MW082810). Pathogenicity test was performed using the mycelial plug inoculation method and repeated twice with five replicates. Healthy MD2 pineapple fruits were surface sterilized with 1% NaOCl solution for15 min. followed by washing with sterilized distilled water. One centimeter diameter PDA plug at the margin of actively growing seven days old cultures were inserted in each of two inoculation wounds made on the skin and stem end of each fruit then the wounds were wrapped with moist cotton wool. Non-colonized PDA plugs were used to inoculate the control fruits. Fruits were incubated under 85% RH at room temperature. Five days after inoculation, the fruits showed similar dark necrotic discoloration and confirmed as N.dimidiatum by PCR (Fig.1G). The Koch postulates were fulfilled by inoculation and re-isolation of the fungal pathogen. This pathogen has also been reported previously to cause economic losses on a number of other hosts, such as pitayah fruits in Israel and Malaysia (Erza et al., 2013; Mohd et al., 2013)) and almond in California (Mohomed et al., 2018). To our knowledge this is the first report of N. dimidiatum causing postharvest stem end rot on MD2 pineapple in Malaysia. It may have the possibility to develop postharvest economic losses to pineapple industry, if severely affected fruits with high population of the pathogen left unattended in store houses.

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