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1.
Plant Dis ; 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938907

RESUMO

Ceylon ironwood (Mesua ferrea Linn.) or Penaga lilin is one of Asia's most popular tropical herbal plants, including Malaysia (Sharma et al., 2017). The trees are cultivated for their aesthetic value and pharmacological properties, especially as traditional remedies for asthma, dermatopathy, inflammation, and rheumatic conditions (Adib et al., 2019). In August 2022, a disease survey was conducted on Ceylon ironwood trees ranging from 5 to 12 years old in Botanical Park, Putrajaya, Malaysia, with 80% exhibiting shoot dieback disease of the 15 trees exhibiting shoot dieback disease. Symptoms include irregular, water-soaked with brown lesions on young leaves and shoots, where the small lesion coalesced and formed broad necrotic regions, subsequently causing dieback and gradual defoliation. Three infected shoots were collected from each tree, excised into small pieces (10 to 20 mm), immersed with 75% ethanol for 3 min, washed with 2% NaOCl solution for 1 min, and rinsed twice for 1 min in sterilized distilled water. A 10 µl aliquot of the sample suspension was streaked onto nutrient agar (NA) and incubated for 24 h to 48 h at 35 °C. A total of 15 isolates with similar morphology were obtained, and each isolate was re-streaked three times to obtain pure colonies that were round, smooth, with irregular edges, and produced yellow pigment in culture. All isolates were Gram-negative, negative for indole production, and utilized glucose, maltose, trehalose, sucrose, D-lactose, and pectin. Three representative isolates (C001, C002, and C003) with similar morphology were selected for further characterization. The total genomic DNA of all isolates was extracted from overnight cultures using Geneaid™ DNA Isolation Kit (Geneaid Biotech Ltd., Taiwan). PCR amplification of 16S rDNA (Zhou et al., 2015) and species-specific infB (Brady et al., 2008) genes was performed, and each of the ~1500 bp and ~900 bp amplicons were sequenced. BLASTn and phylogenetic analyses revealed all isolates were 100% identical to Pantoea anthophila (P. anthophila) LGM 2558 strains (Accession Nos. NR_116749 and NR_116113) for the 16S rDNA gene. They were 99% identical to P. anthophila CL1 strain (Accession Number CP110473) for infB gene. These sequences were later deposited in the GenBank (Accession Nos. OQ772233, OQ772234, and OQ772235 for 16S rDNA gene, and OQ803527, OQ803528, and OQ803529 for infB gene). For the pathogenicity test, healthy Ceylon ironwood seedlings' shoots were inoculated with 10 mL of each isolate suspension (1 x 108 CFU/ml) by spraying the inoculum on the young shoots using a sterilized spray bottle. Control seedlings were inoculated with sterile water. The inoculated shoots were covered with a sealed plastic bag to maintain the moisture and were kept in the greenhouse with temperatures ranging from 26 to 35 °C. The experiments were repeated twice, with three replicates for each treatment. Inoculated shoots showed dieback symptoms like natural infection, including irregular, water-soaked, and brown lesions on leaves and young shoots at 10 days post-inoculation. Control seedlings remained asymptomatic. The pathogen was re-isolated and identified via sequencing of the 16S rDNA and infB genes, thus fulfilling Koch's postulates. Previously, P. anthophila has been reported to cause soft rot in wampee plants in China (Zhou et al., 2015) and leaf blight of cotton in Pakistan (Tufail et al., 2020). To our knowledge, this is the first report of P. anthophila causing shoot dieback disease of Ceylon ironwood trees in Malaysia. Plant disease management strategies need to be established to reduce losses due to P. anthophila infection since the pathogen could limit Ceylon ironwood tree production in Malaysia.

2.
PLoS One ; 18(5): e0285666, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37216342

RESUMO

Entomopathogenic fungi (EPF) are natural enemies which affect insect population and have long been recognized as biological control agents against many insect pests. Some isolates have also been established as endophytes, benefiting their host plants without causing any symptoms or negative effects. Here we demonstrated two entomopathogenic fungal species, Isariajavanica (Frieder. & Bally) Samson & Hywel-jone 2005 and Purpureocillium lilacinum (Thom) Luangsa-ard, Hou-braken, Hywel-Jones & Samson (2011) as endophytes in tomato plants by using the seed inoculation method and examined their effect on plant growth, B. tabaci mortality, and adult emergence. Our study indicated that tomato seeds treated with a fungal suspension of I. javanica and P. lilacinum enabled their recovery from plant tissues (root, stem and leaf) up to 60 days after inoculation (DAI). Both endophytic isolates also caused significant mortality of adult B. tabaci on seedlings inoculated with, I. javanica (51.92±4.78%), and P. lilacinum (45.32±0.20%) compared to the control treatment (19.29±2.35). Adult emergence rates were significantly high in the control treatments (57.50±2.66%) compared to I. javanica (15.00±1.47%) and P. lilacinum (28.75±4.78%) treatments. This study provides evidence that endophytic isolates of I. javanica and P. lilacinum have a biocontrol potentials for used against whiteflies and could also explored as plant growth promoters.


Assuntos
Hemípteros , Hypocreales , Solanum lycopersicum , Animais , Plântula/microbiologia , Plantas
3.
Plant Dis ; 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35748735

RESUMO

Rice (Oryza sativa) is a staple food for most of the world's populations, particularly in Asia (Gumma et al. 2011). The rice sector provides Malaysians with a food supply, food sufficiency, and income for growers (Man et al. 2009). From January to February 2022, panicle samples showing symptoms of bacterial panicle blight (BPB) disease, including reddish-brown, linear lesions with indistinct margins on flag-leaf sheaths and blighted, upright, grayish straw-colored florets with sterile and aborted grains on panicles were collected in granary areas in Sekinchan, Selangor, Malaysia with 90% disease incidence in fields. Surface-sterilization of infected leaf tissue was performed using 75% ethanol and 1% sodium hypochlorite, followed by rinsing three times in sterilized water. Leaf tissue was macerated in sterilized water and aliquots were spread on King's B agar medium, then cultured for 24 h to 48 h at 35 °C. All isolated bacteria were Gram-negative rods, positive for catalase and gelatinase but negative for indole, oxidase and hydrogen sulfide (H2S), and utilized sucrose, inositol, mannitol, glucose, and citrate. Colonies were circular and smooth-margined, producing a diffusible yellowish-green pigment on King's B agar medium, which are characteristics of Burkholderia species (Keith et al. 2005). Five representative isolates (UPMBG7, UPMBG8, UPMBG9, UPMBG15, UPMBG17) were selected for molecular and pathogenicity tests. PCR using specific primers targeting the gyrB gene for molecular characterization was performed, and the ∼470 bp amplicons were sequenced (Maeda et al. 2006) and deposited in GenBank (OM824438 to OM824442). A BLASTn analysis revealed that the five isolates were 99% identical to the B. gladioli reference strains MAFF 302533, GRBB15041, and LMG19584 in GenBank (AB190628, KX638432, and AB220898). A phylogenetic tree using Maximum-likelihood analysis of the gyrB gene sequences showed that the five isolates were 99% identical to B. gladioli reference strains (AB190628, KX638432, and AB220898). To verify the identification of these isolates, the 16S rDNA gene was amplified using 16SF/16SR primers (Ramachandran et al. 2021), producing ~1,400 bp amplicons. The resulting sequences of the five isolates (OM869953 to OM869957) were 98% identical to the reference strains of B. gladioli (NR113629 and NR117553). To confirm pathogenicity, 10 ml suspensions of the five isolates at of 108 CFU/ml were inoculated into the panicles and crowns of 75-day-old rice seedlings of local rice varieties MR269 and MR219 grown in a glasshouse with temperatures ranging from 37 °C to 41 °C (Nandakumar et al. 2009). Control rice seedlings were inoculated with sterilized water. All isolates produced BPB disease symptoms like those originally found in the rice fields at four weeks after inoculation. Control seedlings remained asymptomatic. To fulfill Koch's postulates, the bacteria were reisolated from symptomatic panicles and were confirmed as B. gladioli by sequence analysis of the gyrB and 16S rDNA genes. To our knowledge, this is the first report of B. gladioli causing BPB disease of rice in Malaysia. Since BPB disease causes a significant threat to the rice industry, it is crucial to investigate the diversity of this destructive pathogen for effective disease management strategies in Malaysia.

4.
Plants (Basel) ; 10(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34685980

RESUMO

Blueberry (Vaccinium spp.) plants are exposed to existing and emerging viruses as a result of expanding acreage of blueberry plantations across the world, primarily in North America. Since blueberry is cultivated in areas where there are wild Vaccinium spp., there is increasing risk of virus movement between wild and cultivated blueberries. This is theoretically possible because viruses can spread from commercial cultivars to native species and vice versa causing the spread of existing and new viruses. The occurrence of these viruses in blueberry can be devastating to the industry considering the cost for cultivation and production of this perennial crop. However, the advent of high-throughput sequencing and bioinformatic sequence analysis have allowed for rapid identification of known and novel viruses in any crop including blueberry, thus facilitating proper intervention in response to serious viral diseases. In this paper, we aim to focus on the current status of known and novel viruses emerging in blueberry worldwide, which may impact the blueberry industry.

5.
Biology (Basel) ; 10(9)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34571739

RESUMO

Colletotrichum falcatum Went causes red rot disease in sugarcane farming in the tropical and sub-tropical regions. This disease causes significant economic loss to the sugarcane production industry. Successful disease management strategies depend on understanding the evolutionary relationship between pathogens, genetic diversity, and population structure, particularly at the intra-specific level. Forty-one isolates of C. falcatum were collected from different sugarcane farms across Bangladesh for molecular identification, phylogeny and genetic diversity study. The four genes namely, ITS-rDNA, ß-tubulin, Actin and GAPDH sequences were conducted. All the 41 C. falcatum isolates showed a 99-100% similarity index to the conserved gene sequences in the GenBank database. The phylogram of the four genes revealed that C. falcatum isolates of Bangladesh clustered in the same clade and no distinct geographical structuring were evident within the clade. The four gene sequences revealed that C. falcatum isolates from Bangladesh differed from other countries´ isolates because of nucleotides substitution at different loci. The genetic structure of C. falcatum isolates were determined using ISSR marker generated 404 polymorphic loci from 10 selected markers. The percentage of polymorphic loci was 99.01. The genetic variability at species level was slightly higher than at population level. Total mean gene diversity at the species level was 0.1732 whereas at population level it was 0.1521. The cluster analysis divided 41 isolates into four main genetic groups and the principal component analysis was consistent with cluster analysis. To the best of our knowledge, this is the first finding on characterizing C. falcatum isolates infesting sugarcane in Bangladesh. The results of this present study provide important baseline information vis a vis C. falcatum phylogeny analysis and genetic diversity study.

6.
Plant Dis ; 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34340562

RESUMO

Watermelon (Citrullus lanatus) accounts for almost 13% of all tropical fresh fruit production in Malaysia. They are grown, mostly in Johor, Kedah, Kelantan, Pahang, and Terengganu areas of Malaysia on 10,406 ha and yielding 172,722 Mt. In 2019, a new fruit rot disease was observed in two major production areas in Peninsular Malaysia. Disease symptoms included water-soaked brown lesions on the fruit surface in contact with the soil. The lesions enlarged gradually and ultimately covered the whole fruit with white mycelium leading to internal fruit decay. Disease surveys were conducted in December 2019 and November 2020 in fields at Kuantan, Pahang and Serdang, Selangor. Disease incidence was 10% in 2019 and 15% in 2020. Infected fruits were collected and washed under running tap water to wash off adhering soil and debris. Fruit tissue sections 1 to 2 cm in length were surface sanitized with 0.6% sodium hypochlorite (NaOCl) for 3 min. and washed twice with sterile distilled water. The disinfected air-dried tissues were then transferred onto potato dextrose agar (PDA) media and incubated at 25±2℃ for 3 days. Fungal colonies with whitish mycelium and pink pigment isolated using single spore culture. The pure cultures were placed onto carnation leaf agar (CLA), and the culture plates were incubated at 25±2℃ for 15 days for morphological characterization. On CLA, macroconidia were produced from monophialides on branched conidiophores in orange sporodochia. Macroconindia were thick-walled, strong dorsiventral curvature, 5 to 7 septate with a tapered whip-liked pointed apical cell and characteristic foot-shaped basal cell, 21.9 to 50.98 µm long and 2.3 to 3.60 µm wide. Typical verrucose thick chlamydospores with rough walls were profuse in chains or clumps, sub-globose or ellipsoidal. Based on morphological characteristics they were identified as Fusarium equiseti (Leslie and Summerell 2006). Molecular identification of both U4-1 and N9-1 pure culture isolates were carried out using two primer pair sets; internal transcribed spacer (ITS) ITS-1/ ITS-4 and translation elongation factor 1 alpha (TEF1-α) (EF-1/EF-2). A Blastn analysis of the ITS gene sequence of U4-1(MW362286) and N9-1 (MW362287) showed >99% similarity index to the reference gene sequence of F. equiseti isolate 19MSr-B3-4 (LC514690). The TEF1-α sequences of U4-1 (accession no. MW839563) and N9-1 (accession no. MW839564) showed 100% identity; with an e-value of zero, to the reference gene sequence of F. equiseti isolate URM: 7561 (accession no. LS398490). Each isolate also had a >99% identity with isolate NRRL 34070 (accession no. GQ505642) in Fusarium MLST database that belongs to the F. incarnatum-equiseti species complex (O'Donnell et al. 2015). Based on phylogenetic analysis of the aligned sequences (TEF1-α) by the maximum likelihood method, the U4-1 and N9-1 isolates were confirmed to be F. equiseti as was reported in Georgia, USA (Li and Ji 2015) and in Harbin, Heilongjiang Province, China (Li et al. 2018). Finally, the two pure culture isolates of U4-1 and N9-1 were used to fulfill Koch's postulates. Stab inoculations of five healthy watermelon fruits (cv. 345-F1 hybrid seedless round watermelon) were performed with a microconidial suspension of individual isolates (4x106 spores/mL). Five control fruits were stabbed with double distilled water. The inoculated fruits were incubated under 95% relative humidity at a temperature of 25±2℃ for 48 h followed by additional incubation inside an incubator at 25±2℃ for 8 days. Ten days post-inoculation, the control fruits showed no disease symptoms. However, inoculated fruits exhibited typical symptoms of fruit rot disease like water-soaked brown lesions, white mycelium on the fruit surface and internal fruit decay, which is similar to the farmer's field infected fruits. The suspected pathogen was successfully re-isolated from the symptomatic portion of inoculated fruit and morphologically identified for verification. To our knowledge, this is the first report of F. equiseti causing fruit rot of watermelon in Malaysia. Malaysia exports watermelon year-round to many countries around the world. The outbreak of this new fruit rot disease could potentially pose a concern to watermelon cultivation in Malaysia.

7.
Viruses ; 13(6)2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207047

RESUMO

Southern highbush blueberry (interspecific hybrids of Vaccinium corymbosum L.) is cultivated near wild V. corymbosum as well as closely related species in Florida, USA. The expansion of blueberry cultivation into new areas in Florida and deployment of new cultivars containing viruses can potentially increase the diversity of viruses in wild and cultivated V. corymbosum. In this study, viral diversity in wild and cultivated blueberries (V. corymbosum) is described using a metagenomic approach. RNA viromes from V. corymbosum plants collected from six locations (two cultivated and four wild) in North Central Florida were generated by high throughput sequencing (HTS) and analyzed using a bioinformatic analysis pipeline. De novo assembled contigs obtained from viromes of both commercial and wild sites produced sequences with similarities to plant virus species from a diverse range of families (Amalgaviridae, Caulimoviridae, Endornaviridae, Ophioviridae, Phenuiviridae, and Virgaviridae). In addition, this study has enabled the identification of blueberry latent virus (BlLV) and blueberry mosaic associated ophiovirus (BlMaV) for the first time in Florida, as well as a tentative novel tepovirus (blueberry virus T) (BlVT) in blueberry. To the best of our knowledge, this is the first study that compares viral diversity in wild and cultivated blueberry using a metagenomic approach.


Assuntos
Mirtilos Azuis (Planta)/virologia , Metagenoma , Metagenômica/métodos , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , Viroma , Florida , Frutas/virologia , Vírus de Plantas/classificação
8.
Plant Dis ; 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34042494

RESUMO

Fusarium wilt disease incited by Fusarium oxysporum f. sp. niveum (FON) is the utmost devastating soil-inhabiting fungal pathogen limiting watermelon (Citrullus lanatus) production in Malaysia and globally. The field disease survey of fusarium wilt was carried out during December 2019 and November 2020, in three major production areas (3 farmer fields per location) in Peninsular Malaysia namely, Mersing, Serdang and Kuantan and disease incidence of 30 and 45%, was recorded for each year, respectively. Infected watermelon plants showed symptoms such as vascular discoloration, brown necrotic lesions to the soil line or the crown, one-sided wilt of a plant, or a runner or the whole plant. Infected root and stem tissues, 1-2 cm pieces were surface sterilized with 0.6% NaOCl for 1 minute followed by double washing with sterile water. The disinfected tissues were air-dried and transferred onto semi-selective Komada's medium (Komada 1975) and incubated for 5 days. The fungal colonies produced were placed on potato dextrose agar (PDA) to attain a pure culture and incubated at 25±2℃ for 15 days. The pure fungal colony was flat, round and light purple in color. Macroconidia were straight to slightly curved, 18.56-42.22 µm in length, 2.69-4.08 µm width, predominantly 3 septate and formed in sporodochia. Microconidia measured 6.16-10.86 µm in length and 2.49-3.83 µm in width, kidney-shaped, aseptate and were formed on short monophialides in false-heads. Chlamydospores were single or in pairs with smooth or rough walls, found both terminally or intercalary. To confirm their pathogenicity, two-week-old watermelon seedlings (cv. NEW BEAUTY) were dipped into spore suspension (1 ˟ 106 spores/ml) of representative isolates of JO20 (Mersing), UPM4 (Serdang) and KU41 (Kuantan) for 30 second and then moved into 10 cm diameter plastic pots containing 300 g sterilized soil mix. Disease symptoms were assessed weekly for one month. Control seedlings were immersed in sterile distilled water before transplanting. The inoculated seedlings showed typical Fusarium wilt symptoms like yellowing, stunted growth, and wilting, which is similar to the farmer field infected plants. However, the seedlings inoculated by sterile distilled water remained asymptomatic. The pathogen was successfully re-isolated from the infected seedlings onto Komada's medium, fulfilling the Koch's postulate. For the PCR amplification, primers EF-1 and EF-2 were used to amplify the tef1-α region. A Blastn analysis of the tef1-α sequences of the isolates JO20 (accession nos. MW315902), UPM4 (MW839560) and KU41 (MW839562) showed 100% similarity; with e-value of zero, to the reference sequences of F. oxysporum isolate FJAT-31690 (MN507110) and F. oxysporum f. sp. niveum isolate FON2 790-2 (MN057702). In Fusarium MLST database, isolates JO20, UPM4 and KU41 revealed 100% identity with the reference isolate of NRRL 22518 (accession no. FJ985265). Though isolate FJ985265 belongs to the f. sp. melonis, earlier findings had revealed Fusarium oxysporum f. sp. are naturally polyphyletic and making clusters with diverse groups of the Fusarium oxysporum species complex (O'Donnell et al. 2015). The isolates JO20, UPM4 and KU41 were identified as F. oxysporum f. sp. niveum based on the aligned sequences of tef1-α and molecular phylogenetic exploration by the maximum likelihood method. To the best of our knowledge, this is the first report of F. oxysporum f. sp. niveum as a causative pathogen of Fusarium wilt disease of watermelon in Malaysia. Malaysia enables to export watermelon all-year-round in different countries like Singapore, Hong-Kong, The United Arab Emirates (UAE), and Netherlands. The outburst of this destructive soil-borne fungal pathogen could cause hindrance to watermelon cultivation in Malaysia. Thus, growers need to choice multiple management tactics such as resistant varieties, cultural practices (soil amendments and solarization), grafting, cover crops and fungicide application to control this new pathogen.

9.
Plant Dis ; 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858187

RESUMO

Plumeria alba L. is a flowering plant in the family Apocynaceae and widely cultivated in Malaysia as a cosmopolitan ornamental plant. In January 2020, anthracnose lesions were observed on leaves of Plumeria alba planted in Agricultural Farm, Universiti Putra Malaysia, in Selangor state, Malaysia. The disease mainly affected the leaves with symptoms occurring with approximately a 60% disease incidence. Ten symptomatic leaves were sampled from 3 different trees in the farm. Symptoms initiated as small circular necrotic spots that rapidly enlarged into black lesions with pale brown borders. Diseased tissues (5×5 mm) were surface-sterilized with 70% ethanol for 1 min, rinsed three times with sterile distilled water, dried on sterile filter papers, plated on PDA and, incubated at 25 °C with a 12-h photoperiod. A total of seven single-spore isolates with similar colony morphologies were obtained from tissue samples. After 7 days, the colonies raised the entire margin and showed white-to-gray aerial mycelium, orange conidial masses in the center and appeared dark brown at the center of the reverse view. The conidia were 1-celled, hyaline, smooth-walled, cylindrical with narrowing at the center, averaged (13-15 µm × 3 - 4 µm) (n=40) in size. Morphological characteristics of the isolates were similar to those detailed in taxonomic description of Colletotrichum sp. (Prihastuti et al. 2009). For molecular identification, genomic DNA of two representative isolates, PL3 and PL4 was extracted from fresh mycelium using DNeasy Plant Mini Kit (Qiagen, USA). The internal transcribed spacer (ITS) region, actin (ACT) and calmodulin (CAL) genes were amplified using ITS5/ITS4 (White et al. 1990), ACT-512F/783R (Carbone and Kohn 1999) and CL1C/CL2C primer sets (Weir et al. 2012). A BLAST nucleotide search of GenBank using ITS sequences showed 100% identity to Colletotrichum siamense ex-type culture ICMP 18578 (GenBank accession no. JX010171). ACT and CAL sequences showed 100% identity with C. siamense ex-type isolate BPD-I2 (GenBank accession no. FJ907423 and FJ917505). The sequences were deposited in GenBank (ITS: accession nos. MW335128, MT912574), ACT: accession nos. MW341257, MW341256, CAL: accession nos. MW341255 and MT919260). Based on these morphological and molecular characteristics, the fungus was identified as C. siamense. Pathogenicity of PL3 and PL4 isolates was verified using four healthy detached leaves of Plumeria alba. The leaves were surface-sterilized using 70% ethanol and rinsed twice with sterile water before inoculation. The leaves (three inoculation sites/leaf) were wounded by puncturing with a sterile needle through the leaf cuticle and inoculated in the wound site with 10-µl of conidial suspension (1×106 conidia/ml) from 7-days-old culture on PDA. Four leaves were used as a control and were inoculated only with 10-µl of sterile distilled water. Inoculated leaves were kept in humid chambers for 2 weeks at 25 °C with 98% relative humidity on a 12-h fluorescent light/dark period. The experiment was repeated three times. Anthracnose symptoms were observed on all inoculated leaves after 3 days, whereas controls showed no symptoms. Fungal isolates from the diseased leaves showed the same morphological characteristics as isolates PL3 and PL4, confirming Koch's postulates. C. siamense has been reported causing anthracnose on rose (Rosa chinensis) in China (Feng et al. 2019), Coffea arabica in Thailand (Prihastuti et al. 2009) and mango leaf anthracnose in Vietnam (Li et al. 2020). To our knowledge, this is the first report of Colletrotrichum siamense causing leaf anthracnose on Plumeria alba in Malaysia. Accurate identification of this pathogen provides a foundation in controlling anthracnose disease on Plumeria alba.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33376497

RESUMO

Polypores are mushrooms which are rich in bioactivities and for generations, they have been widely used as herbal remedies. Despite their significant importance in treatments of various health issues, only a few local species have been reported for their pharmacological potentials. The present study was carried out to establish cytotoxicity potentials of Donkioporiella mellea, a local polypore species collected from forested areas in Malaysia at cellular levels on normal human lung (MRC5) and human lung carcinoma (A549) cell lines. Survival and inhibition rates were analyzed by 3-(4, 5)-dimethylthiahiazo (-z-y-l)-2,5-diphenyltetrazoliumbromide (MTT) while monitoring changes on cellular shapes by inverted phase contrast microscopy. Survival rates of MRC5 cells were observed to be significantly higher than A549 after treatments with various concentrations of polypore extracts. MRC5 cells showed excellence in survival performance when treated with hot and cold aqueous extracts. Cold aqueous extract showed higher cytotoxicity activities compared to hot aqueous extract (p < 0.0001) with inhibitory concentration (IC50) values of 414.29 µg/ml and >1000 µg/ml, respectively. Treatments with tamoxifen as a control exhibited necrotic features in both cell lines. The results suggest that D. mellea possesses pharmacological potentials that can be utilized for human consumption as a new bioresource alternative, thus encouraging research advancement in mycological and nutraceutical studies.

11.
Insects ; 11(9)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927701

RESUMO

Whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), consists of genetically diverse species known to cause significant destruction in several crops around the world. Nymphs and adults of B. tabaci cause damage to plants during feeding, and they can act as a virus vector, thus causing significant yield loss to crops in the tropical and subtropical regions. Chemical pesticides are widely used to control B. tabaci due to their immediate action, but this approach has several drawbacks including food safety issues, insecticide resistance, environmental pollution, and the effect on non-target organisms. A biological control agent using entomopathogenic fungi (EPF) has therefore been developed as an alternative against the conventional use of chemical pesticides in an integrated pest management (IPM) system to effectively control B. tabaci. It is apparent from this review that species of hyphomycetes fungi are the most common EPF used to effectively control B. tabaci, with the second instar being the most susceptible stage of infection. Therefore, this review article focuses specifically on the control of B. tabaci with special emphasis on the use of EPF as biological control agents and their integration in IPM.

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