Papers by Masratul Hawa Mohd
White spider lily (Hymenocallis littoralis), locally known as Melong Kecil, is a herbaceous and b... more White spider lily (Hymenocallis littoralis), locally known as Melong Kecil, is a herbaceous and bulbous perennial plant, commonly planted in Malaysia due to its medicinal and ornamental properties. Symptoms of leaf blight on H. littoralis were noticed in early September 2015 in Permatang Pauh, Penang with an incidence of up to 35%. The symptoms appeared as irregular reddish-brown lesion with black pycnidia scattered on the leaf . When aged, the lesion enlarged and became darker.
Pineapple (Ananas comosus) is one the important fruit crops planted in Malaysia, and this study w... more Pineapple (Ananas comosus) is one the important fruit crops planted in Malaysia, and this study was conducted to determine Fusarium spp. associated with diseases of the fruit crop as Fusarium is prevalent in tropical countries. Our objective was to identify and characterize Fusarium spp. associated with pineapple fruit rot and leaf spot mainly found on the fruits and leaves in Peninsular Malaysia. Fusarium isolates (n = 108) associated with pineapple fruit rot and leaf spot were characterized by morphological, molecular and phylogenetic analyses, a mating study and pathogenicity testing. TEF-1α sequence analysis identified Fusarium proliferatum, Fusarium verticillioides, Fusarium sacchari and Fusarium sp. Mating was successful only between tester strains of F. pro-liferatum and F. verticillioides. Sexual crosses with standard tester strains showed that 82 isolates of F. proliferatum produced fertile crosses with mating population D (Gibberella intermedia) and three isolates of F. verticillioides were fertile with the tester strain of mating population A (Gibberella moniliformis). All isolates were pathogenic, causing pineapple fruit rot and leaf spot, thus fulfilling Koch's postulates.
Stem rot was recorded as one of serious diseases of red-fleshed dragon fruit, (Hylocereus polyrhi... more Stem rot was recorded as one of serious diseases of red-fleshed dragon fruit, (Hylocereus polyrhizus), in Malaysia. Fusarium fujikuroi was recovered from stem rot lesion of H. polyrhizus and the species was identified using TEF1-í µí»¼ sequence and mating study. From maximum likelihood phylogenetic tree using combined TEF1-í µí»¼ and í µí»½-tubulin sequences, the F. fujikuroi isolates from stem rot were grouped according to three geographical locations, namely Peninsular Malaysia, Sabah and Sarawak. Phylogenetic analysis indicated that F. fujikuroi isolates from stem rot of H. polyrhizus were clustered separately from F. fujikuroi isolates from rice because of intraspecific variation. From amplification of MAT allele-specific primers, 20% of the isolates carried MAT-1 allele while 80% carried MAT-2 allele. From isolates that carried MAT-1 allele, 65% crossed-fertile with MP-C (mating population of F. fujikuroi) tester strain while for MAT-2 allele, 56% crossed-fertile with MP-C. None of the isolates were identified as MP-D (mating population of F. proliferatum). Pathogenicity test conducted on 40 representative isolates showed that the stem rot symptoms were similar with the symptoms observed in the field, and can be categorized as low, moderate and high aggressiveness, which indicated variation in pathogenicity and virulence among the isolates. This study provides novel findings regarding Fusarium species associated with stem rot of H. polyrhizus and indicated that F. fujikuroi as a new causal pathogen of the disease.
Wild mushrooms including Boletus are among edible mushrooms consumed by local populations. Howeve... more Wild mushrooms including Boletus are among edible mushrooms consumed by local populations. However, the species identity for many types of wild edible mushroom in Malaysia is poorly known. The present study was conducted to identify and to determine factors affecting in-vitro growth of an edible Boletus sp. (kulat gelam) commonly found in peat swamp forests in Bachok, Kelantan. Identification was initially done using macroscopic and microscopic characteristics of the fruiting bodies. However, due to overlapping chemical colour reactions, morphological and anatomical characteristics of the fruiting body with other Boletus species, species identity was confirmed using ITS region, and the mushroom was identified as Boletus griseipurpureus. A toxicity test indicated that B. griseipurpureus is an edible mushroom with low toxic levels (LC 50 =4.33 mg/mL). From growth studies, the results suggested that potato dextrose agar (PDA), cassava dextrose agar (CDA) and yeast malt extract (YME) were the most suitable artificial media for mycelial growth of B. griseipurpureus at pH 6.0 and 30°C. To our knowledge, this is the first documented report on wild edible mushroom B. griseipurpureus in Malaysia.
Many species of Fusarium are pathogenic as well toxigenic to a wide variety of plants. The presen... more Many species of Fusarium are pathogenic as well toxigenic to a wide variety of plants. The present study was conducted to determine the ability of four members of Fusarium fujikuroi species complex and F. oxysporum from various crops to produce fumonisin B1 (FB 1). Isolates of Fusarium species from infected parts of asparagus, ginger, oil palm, mango, banana, maize, and rice were identified as F. verticillioides (11 isolates), F. proliferatum (50 isolates), F. fujikuroi (24 isolates), F. andiyazi (six isolates), and F. oxysporum (32 isolates). FUM1, a gene involved in fumonisin biosynthesis, was detected in 94 isolates of F. verticillioides (11 isolates), F. proliferatum (49 isolates), F. fujikuroi (24 isolates), and F. oxysporum (10 isolates) but only 61 were positive for FB 1 when tested using RIDA ® Quick Fumonisin test strip, indicating that the presence of FUM1 was not necessarily associated with FB 1 production. Based on ultra-high performance liquid chromatography, all the 61 isolates were detected to produce FB 1 , at variable levels, with concentrations ranging from 0.60 to 29.2 mg/g. Our results suggested that there is a potential risk of FB 1 contamination in agricultural crops in Malaysia.
Dragon fruit (Hylocereus spp.) is a group of desert plants originated from South and Central Amer... more Dragon fruit (Hylocereus spp.) is a group of desert plants originated from South and Central America. Red-fleshed dragon fruit (H. polyrhizus) is planted worldwide and becoming popular in Southeast Asia including Malaysia. Recently, this exotic crop, especially in Southeast Asia, was heavily infected by several economically important diseases caused by fungi, bacteria, viruses, insects and other pests. This study was carried out to investigate the aethiology of the causal pathogen that caused a new disease on H. polyrhizus in Southeast Asia. The infected stems and fruits of H. polyrhizus were collected and classified into several groups according to the external symptoms. Margins of the symptoms that showed water-soaked and brownish lesions were surface-sterilized, and placed onto half-strength potato dextrose agar (PDA) and peptone pentachloronitrobenzene agar (PPA) plates. Isolates of one of the dominant resulting fungi were single-spored and identified based on morphological char...
CHARACTERIZATIONS, PATHOGENICITY AND CHEMICAL CONTROL OF Fusarium SPECIES FROM STEM ROT OF DRAGON... more CHARACTERIZATIONS, PATHOGENICITY AND CHEMICAL CONTROL OF Fusarium SPECIES FROM STEM ROT OF DRAGON FRUIT (Hylocereus polyrhizus) IN MALAYSIA ABSTRACT A new disease of stem rot was observed in 20 dragon fruit plantations in Malaysia during a disease survey in 2008 and 2009. The symptom observed was brown sunken lesion and the infected stems finally rotted and dried. Therefore, the objectives of the present study were to isolate, identify and characterize the causal pathogen of stem rot of red-fleshed dragon fruit (Hylocereus polyrhizus) based on morphological, molecular, mating study, pathogenicity test, mycotoxin analysis as well as to evaluate the efficacy of fungicides to control the fungal pathogen. A total of 200 isolates of Fusarium were isolated from the stem rot symptoms. Based on morphological characteristics, all isolates were identified as Fusarium proliferatum. Based on translation elongation factor 1-alpha (TEF1-α) and β-tubulin sequences, 83 isolates were identified as F...
IDENTIFICATION, PATHOGENICITY AND MYCOTOXIN PRODUCTION OF Fusarium proliferatum FROM STEM ROT OF ... more IDENTIFICATION, PATHOGENICITY AND MYCOTOXIN PRODUCTION OF Fusarium proliferatum FROM STEM ROT OF RED-FLESHED DRAGON FRUIT (Hylocereus polyrhizus) IN MALAYSIA *Masratul Hawa Mohd, Baharuddin Salleh and Latiffah Zakaria School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia *Corresponding author: [email protected] ABSTRACT During a survey conducted from 2008 to 2009, Fusarium proliferatum was found associated with red-fleshed dragon fruit (Hylocereus polyrhizus) showing symptom of stem rot. The symptom appeared as circular, brown sunken lesion with orange sporodochia and white mycelium formation on the lesion surface. Twenty-two isolates of Fusarium were isolated from stem rot of H. polyrhizus and were morphologically identified as F. proliferatum based on microscopic and macroscopic characteristics. To confirm species identity, DNA sequencing of translation elongation factor 1-alpha (TEF1-α) was carried out. Based on BLAST search of TEF1-α sequence,...
Dragon fruit (Hylocereus polyrhizus) is a recently introduced fruit crop in Southeast Asia, inclu... more Dragon fruit (Hylocereus polyrhizus) is a recently introduced fruit crop in Southeast Asia, including Malaysia. At present, the acreage of dragon fruit in Malaysia is ca 800 ha and increasing due to its economic values and being promoted as a healthy fruit. Like many other crops, however, dragon fruit is also subjected to several economically important diseases caused by fungi, bacteria and viruses. This study was carried out to investigate the identity and pathogenicity of fungi associated with symptoms of anthracnose on dragon fruit in Malaysia. The samples of diseased plants and fruits were collected and classified into several groups according to external symptoms. The margin of the symptoms were surface-sterilized by gently swapping with sterile cotton wools moistened with 70% ethanol (1 min), cut into small pieces (ca 2 x 2 x 2 cm), dipped in 5% clorox (3 min), and rinsed in several changes of sterile distilled water (1 min), and isolated onto potato dextrose agar (PDA) and w...
Dragon fruit belongs to the genus Hylocereus in family Cactacae. The plant is widely cultivated i... more Dragon fruit belongs to the genus Hylocereus in family Cactacae. The plant is widely cultivated in Southeast Asia, including Malaysia. Hylocereus polyrhizus is considered to be new and promising fruit species. However, the fruits and stems of H. polyrhizus were heavily infected by several diseases caused by fungi, bacteria, viruses and insects. Samples of H. polyrhizus showing disease symptom were collected from Penang, Perak, and Negeri Sembilan. Among 100 of fungal isolates obtained from diseased dragon fruit, 19 isolates of Geotrichum candidum were obtained and identified by using morphological characteristics of single-spored cultures on malt extract agar (MEA) and cornmeal agar (CMA) at 25°C e.g. the arthrospore formation, true hyphae, vegetative cells, colony morphology, growth rates and pathogenicity tests. G. candidum is a cosmopolitan fungus with worldwide distribution that can be isolated from soils and plants. G. candidum however, has no conidiophores. The spores were for...
This study was conducted to characterize isolates of Fusarium species based on Translation Elonga... more This study was conducted to characterize isolates of Fusarium species based on Translation Elongation Factor 1-Alpha (TEF1-α) gene and to study the phylogenetic relationships among the isolates using Neighbor-joining (NJ) tree. A total of 20 isolates of each species were subjected to PCR amplification of TEF1-α gene using EF1 and EF2 primers. The purified PCR products were sent to a service provider for DNA sequencing. The DNA sequences were aligned using ClusterW Multiple Alignment in Molecular Evolutionary Genetic Analysis (MEGA 5) and Basic Local Alignment Search Tool (BLAST) was used to perform similarity searches. Multiple sequences alignment based on TEF1-α gene sequence of all isolates were generated and used to construct NJ tree. Jukes-Cantor model was used to construct NJ tree and reliability of the tree was estimated with 1000 replications. Isolates of F. fujikuroi and F. proliferatum from GenBank were included in the analysis and F. solani was used as outgroup. From PCR a...
Pineapple (Ananas comosus) in Peninsular Malaysia is planted for local consumption and for export... more Pineapple (Ananas comosus) in Peninsular Malaysia is planted for local consumption and for export. Symptoms of fruit rot were observed on Moris, Josapine, and Gandul varieties in several farms in December 2010 to November 2011 in the states of Kedah, Penang, Perak, Selangor, Negeri Sembilan, and Johor. The fruits appeared rotten with sunken fruit skin, brown lesions, and mycelia in the lesions of some infected fruits. Diseased tissues (5 × 5 mm) were surface disinfected with 1% sodium hypochlorite, rinsed with sterile distilled water, and plated onto peptone pentachloronitrobenzene agar. All the plates were incubated in 12-h alternate light and dark at 28°C. Single-spore isolates were used for morphological identification which revealed the presence of F. oxysporum and F. solani (Leslie and Summerell 2006). Fusarium oxysporum produced dense, cottony, thick, floccose mycelia with purplish to white pigmentation and abundant pale orange sporodochia. Macroconidia (27.07 to 42.54 × 2.76 to 4.23 μm) were straight to slightly curved, 3 to 5-septa with hook-like apical cell and pointed foot-shaped basal
Fusariosis symptoms were detected on pineapple fruits and leaves in several states in Peninsular ... more Fusariosis symptoms were detected on pineapple fruits and leaves in several states in Peninsular Malaysia. Eight Fusarium fujikuroi isolates were isolated and identified using a partial Translation Elongation Factor-1α (TEF) and β-tubulin sequences. The isolates showed 98–100 % similarity with F. fujikuroi NRRL43610. Phylogenetic analysis of the combined TEF and β-tubulin sequences showed that the eight isolates clustered with F. fujikuroi from rice. Koch's postulates were fulfilled on pineapple fruits and leaves confirming path-ogenicity of the F. fujikuroi isolates.
During a series of sampling in 2008 and 2009, stem rot disease was detected in Hylocereus polyrhi... more During a series of sampling in 2008 and 2009, stem rot disease was detected in Hylocereus polyrhizus plantations in Malaysia, with symptom appeared as circular, brown sunken lesion with orange sporodochia and white mycelium formation on the lesion surface. Eighty-three isolates of Fusarium were isolated from 20 plantations and were morphologically identified as F. proliferatum based on the variability of colony appearance, pigmentation, growth rate, length of chains, production of bluish sclerotia, concentric ring aerial mycelium and sporodochia. Three species-specific primers, namely ITS1/proITS-R, PRO1/2 and Fp3-F/4-R successfully produced PCR products and confirmed that the isolates from stem rot of H. polyrhizus were F. proliferatum isolates. From BLAST search of translation elongation factor 1-alpha (TEF1-α) sequences, the isolates showed 99–100% similarity with F. proliferatum deposited in GenBank which further confirmed that the isolates were F. proliferatum. The results from amplification of MAT-allele specific primers indicated that 14.5% of F. proliferatum isolates carried MAT-1 allele and 85.5% carried MAT-2. Crossing results showed that all 83 F. proliferatum isolates were male fertile showing positive crosses with the tester strains of MATD-1 and MATD-2. Perithecia oozing ascospore were produced. Forty isolates as representative were evaluated for pathogenicity test, produced rot symptoms similar to those observed in the fields which confirmed the isolates as the causal agent of stem rot of H. polyrhizus. To our knowledge, this is the first report of stem rot of H. polyrhizus caused by F. proliferatum in Malaysia.
![Research paper thumbnail of Characterization and intraspecific variation of Fusarium semitectum (Berkeley and Ravenel) associated with red-fleshed dragon fruit (Hylocereus polyrhizus [Weber] Britton and Rose) in Malaysia](https://attachments.academia-assets.com/47683629/thumbnails/1.jpg)
A total of 79 isolates of Fusarium semitectum were characterized by morphological and IGS-RFLP an... more A total of 79 isolates of Fusarium semitectum were characterized by morphological and IGS-RFLP analysis to assess its intraspecific variation. Based on morphological characteristics, the isolates of F. semitectum were classified into 2 distinct groups, morphotypes I and II. Morphotype I was characterized by longer macroconidia (3-septate: 31.03 ± 2.57 µm; 5-septate: 40.17 ± 1.85 µm), 0-7 septate with 5-septate was the most common, absence of chlamydospores, presence of sporodochia, abundant-floccose mycelium, peach colony appearance, peach to orange pigmentations and fast growing. While isolates of morphotype II produced shorter macroconidia (3-septate: 24.98 ± 1.87 µm; 5-septate: 35.24 ± 2.07 µm), 0-5 septate with 3-septate was the most common, with (56%) or without chlamydospores (44%), without sporodochia, abundant-floccose and abundant-powdery mycelium, beige to brown colonies, brown to dark brown pigmentations and slow growing. Corresponding to the morphological characterization, IGS-RFLP analysis indicated that the 79 isolates could be divided into 2 different clusters assigned as RFLP groups I and II. 49 IGS haplotypes were produced by 8 restriction enzymes (AluI, Bsu15I, BsuRI, Eco881, Hin6I, MspI, PstI and TaqI) which indicated a high level of intraspecific variation and polymorphism among the 79 isolates. This is the first report of F. semitectum associated with H. polyrhizus.
Red-fleshed dragon fruit (Hylocereus polyrhizus [Weber] Britton & Rose) is a newly introduced and... more Red-fleshed dragon fruit (Hylocereus polyrhizus [Weber] Britton & Rose) is a newly introduced and potential crop in the Malaysian fruit industry. Besides its nutritious value, the fruit is being promoted as a health crop throughout Southeast Asia. In April of 2007, a new disease was observed in major plantations of H. polyrhizus throughout five states (Kelantan, Melaka, Negeri Sembilan, Penang, and Perak) in Malaysia with 41 and 25% disease incidence and severity, respectively. Stems of H. polyrhizus showed spots or small, circular, faint pink-to-beige necrotic lesions that generally coalesced as symptoms progressed. Symptom margins of diseased stem samples were surface sterilized with a 70% alcohol swab, cut into small blocks (1.5 × 1.5 × 1.5 cm), soaked in 1% sodium hypochlorite (NaOCI) for 3 min, and rinsed in several changes of sterile distilled water (each 1 min). The surface-sterilized tissues were placed onto potato dextrose agar (PDA) and incubated under alternating 12-h daylight and black light for 7 days. A fungus was consistently isolated from the stems of symptomatic H. polyrhizus and identified as Curvularia lunata (Wakker) Beodijn (1–3) that showed pale brown multicelled conidia (phragmoconidia; three to five celled) that formed apically through a pore (poroconidia) in sympodially, elongating, geniculated conidiophores. Conidia are relatively fusiform, cylindrical, or slightly curved, with one of the central cells being larger and darker (26.15 ± 0.05 μm). All 25 isolates of C. lunata obtained from diseased H. polyrhizus are deposited at the Culture Collection Unit, Universiti Sains Malaysia and available on request. Isolates were tested for pathogenicity by injecting conidial suspensions (1 × 10 6 conidia/ml) and pricking colonized toothpicks on 25 healthy H. polyrhizus stems.
During the year 2008 to 2009, a new disease of stem canker was noticed in most red-fleshed dragon... more During the year 2008 to 2009, a new disease of stem canker was noticed in most red-fleshed dragon fruit (Hylocereus polyrhizus) plantations in Malaysia. The symptoms observed were small circular sunken orange spot, black pycnidia and rotted stem. This study was conducted to determine the occurrence of the stem canker on H. polyrhizus in Malaysia, subsequently to isolate, identify and characterize the fungal pathogen based on morphology and molecular characteristics and pathogenicity test. From the surveyed 20 plantations in Malaysia, stem canker was detected in all the plantations. A total of 40 isolates of Scytalidium-like fungus were isolated and identified as Neoscytalidium dimidiatum based on morphological characteristics and ITS region sequences, which showed 99% similarity to N. di-midiatum (FJ648577). From the phylogenetic analysis using maximum-likelihood tree, isolates of N. dimidiatum from stem canker of H. polyrhizus were grouped together and did not show any sequence variation. From pathogenicity test, all 40 isolates of N. dimidiatum were pathogenic causing stem canker on H. polyrhizus. To our knowledge, this is the first report of stem canker of H. polyrhizus caused by N. dimidiatum in Malaysia.
Conference Presentations by Masratul Hawa Mohd
Dragon fruit or pitaya or locally known as 'buah naga' is a nutritious and exotic fruit that has ... more Dragon fruit or pitaya or locally known as 'buah naga' is a nutritious and exotic fruit that has gained a place in Malaysian fruit industry. To be compared with other tropical fruits, this newcomer fruit has been planted in a small scale at the beginning and until to date, Malaysia has over 1200 ha growing areas of pitaya. The suitability of tropical climate, rainfall requirements, light intensity and soil types may contribute to the successful cultivation of dragon fruit in Malaysia. However, like many other fruit crops, pitaya in Malaysia was seriously infected with several complex diseases caused by fungi due to improper agricultural practices and other environmental factors such as temperature and humidity. The identified fungal diseases were anthracnose caused by Colletotrichum gloeosporioides and C. truncatum, stem necrosis by Curvularia lunata, stem canker by Neoscytalidium dimidiatum, stem rot by Fusarium proliferatum and the latest disease found was reddish-brown spot caused by Nigrospora sphaerica. The present report gives inclusive information regarding various aspects on symptomology, pathogenicity, morphological and molecular identification of the causal pathogens and providing recommendation on disease control method of dragon fruit.
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Papers by Masratul Hawa Mohd
Conference Presentations by Masratul Hawa Mohd