1.Colletotrichum spp. associated with agricultural crops in Malaysia, causal pathogens and potential control methods
Malaysian Journal of Microbiology 2020;16(6):530-544
ABSTRACT
Colletotrichum is one of the most significant and common plant pathogens, infecting many economically important crops
worldwide. Colletotrichum is also one of the most studied fungal genera in Malaysia because it contains many species
that infect various types of agricultural crop including fruit, vegetable and industrial crops. Studies on Colletotrichum spp.
are mostly focused on the causal pathogens, the host range and disease management. Among the host crops, most
studies on Colletotrichum spp. have been conducted on infection in chilli (Capsicum spp.), which, in Malaysia, first arose
in the 1980s and still continues to be a problem to this day. Studies have also been conducted on Colletotrichum spp.
associated with anthracnose in fruit crops including dragon fruit, papaya, banana and mango. Disease management of
anthracnose pathogens postharvest has also been conducted to prolong the shelf life of these fruit crops. In this review,
Colletotrichum spp. associated with chilli and several fruit crops as well as their disease management are highlighted.
There have been many changes in Colletotrichum taxonomy and systematics in recent years, affecting the identification
of anthracnose pathogens reported in Malaysia. Colletotrichum species identified solely by morphology or solely via the
internal transcribed spacer (ITS) region should be referred to as sensu lato (in the broad sense) since many species
belong to species complexes. Species within a species complex are closely related, and most are cryptic species
particularly species in the C. gloeosporioides and C. acutatum complexes which are commonly associated with
agricultural crops in Malaysia. Due to the importance of Colletotrichum spp. as plant pathogens, up-to-date identification
methods should be used since accurate species identification of Colletotrichum is crucial for formulating suitable disease
management programmes as well as for plant quarantine and biosecurity purposes. This review provides the current
knowledge on the status of Colletotrichum spp. associated with agricultural crops in Malaysia and potential control
methods on different types of agricultural crops.
Colletotrichum--pathogenicity
2.Selection and Efficacy of Soil Bacteria Inducing Systemic Resistance Against Colletotrichum orbiculare on Cucumber.
Min Sun KWACK ; Seung Gyu PARK ; Yong Chull JEUN ; Ki Deok KIM
Mycobiology 2002;30(1):31-36
Soil bacteria were screened for the ability to control cucumber anthracnose caused by Colletotrichum orbiculare through induced systemic resistance (ISR). Sixty-four bacterial strains having in vitro antifungal activity were used for selecting ISR-inducing strains in cucumber. Cucumber seeds (cv. Baeknokdadagi) were sown in potting mixtures incorporated with the soil bacteria, at a rate of ca. 10(8) cells per gram of the mixture. Two week-old plants were then transplanted into the steam-sterilized soil. Three leaf-stage plants were inoculated with a conidial suspension (5x10(5) conidia/ml) of C. orbiculare. Diseased leaf area (%) and number of lesions per cm2 leaf were evaluated on third leaves of the plants, 5~6 days after inoculation. Among 64 strains tested, nine strains, GC-B19, GC-B35, GK-B18, MM-B22, PK-B14, RC-B41, RC-B64, RC-B65, and RC-B77 significantly (P = 0.05) reduced anthracnose disease compared to the untreated control. In contrast, some bacterial strains promoted susceptibility of cucumber to the disease. From the repeated experiments using the nine bacterial strains, GC-B19, MM-B22, PK-B14, and RC-B65 significantly (P = 0.05) reduced both diseased leaf area (%) and number of lesions per cm2 leaf in at lease one experiment. These strains with control efficacy of 37~80% were determined to be effective ISR-inducing strains.
Bacteria*
;
Colletotrichum*
;
Soil*
3.A new phenolic acid ester from solid culture of Colletotrichum capsici, an endophytic fungus from Paeonia lactiflora.
Yan-Bin SUN ; Gui-Yang XIA ; Huan XIA ; Yu-Zhuo WU ; Ling-Yan WANG ; Sheng LIN
China Journal of Chinese Materia Medica 2021;46(11):2837-2842
A new phenolic acid ester, 4'-hydroxyphenylethyl 4,8(R)-dihydroxyphenylpropionate(1), was isolated from an endophytic fungus Colletotrichum capsici of Paeonia lactiflora roots, along with eight known phenolic derivatives, tyrosol(2), 2-(4-hydroxyphenyl) ethyl acetate(3), methyl p-hydroxyphenylacetate(4), methyl m-hydroxyphenylacetate(5), 4-(4-hydroxyphene-thoxy)-4-oxobutanoic acid(6), 4-hydroxyphenethyl methyl succinate(7), trichodenol B(8) and 4-hydroxyphenethyl 2-(4-hydroxyphenyl) acetate(9). Their structures were identified by a combination of high-resolution electrospray ionization mass spectrometry(HR-ESI-MS), nuclear magnetic resonance(NMR) spectroscopy, ultraviolet(UV) spectroscopy and electronic circular dichroism(ECD) spectroscopy. Compounds 2-9 were isolated from this fungus for the first time.
Colletotrichum
;
Esters
;
Hydroxybenzoates
;
Paeonia
4.Occurrence of Anthracnose on English Ivy Caused by Colletotrichum trichellum in Korea.
Wan Gyu KIM ; Sung Kee HONG ; Weon Dae CHO
Mycobiology 2001;29(2):107-109
Anthracnose symptoms severely occurred up to 50% on leaves of English ivy growing in greenhouses in Cheongwon area of Korea during disease survey in April, 2000. The symptoms developed as concentric spots with dot-like acervuli on leaves of the plant. A total of 24 isolates of Colletotrichum sp. were obtained from the spotted lesions and identified as Colletotrichum trichellum based on the morphological and cultural characteristics. Leaf spots similar to the original anthracnose symptoms were induced on the host leaves by artificial inoculation with the isolates of the fungus. This is the first record of C. trichellum causing anthracnose of English ivy in Korea.
Colletotrichum*
;
Cultural Characteristics
;
Fungi
;
Hedera*
;
Korea*
;
Plants
5.Spot Anthracnose Disease Caused by Colletotrichum gloeosporioides on Tulip Tree in Korea.
Okryun CHOI ; Okhee CHOI ; Youn Sig KWAK ; Jinwoo KIM ; Jin Hyeuk KWON
Mycobiology 2012;40(1):82-84
The tulip tree (Liriodendron chinense) has been widely cultivated in Korea as a street or garden tree for its large flowers, which have a superficial resemblance to tulips. Occurrence of anthracnose disease on the leaves of tulip trees growing on the campus of Gyeongsang National University, Jinju, Korea, has been observed. Based on mycological characteristics, pathogenicity, and internal transcribed spacer sequence, the causal fungus was identified as Colletotrichum gloeosporioides. This is the first report on anthracnose disease caused by C. gloeosporioides on tulip trees in Korea.
Colletotrichum
;
Flowers
;
Fungi
;
Korea
;
Liriodendron
;
Trees
;
Tulipa
6.Anthracnose of May Lily Caused by Colletotrichum liliacearum.
Wan Gyu KIM ; Sung Kee HONG ; Weon Dae CHO
Mycobiology 2002;30(1):57-59
Anthracnose symptoms severely occurred up to 100% on leaves of May lily grown in four locations in Korea during a disease survey in 2001. The symptoms appeared as circular to irregular spots with brown to dark brown discoloration on leaves of the plant, and severely infected leaves blighted. A total of 35 isolates of Colletotrichum sp. was obtained from the spotted lesions and identified as Colletotrichum liliacearum based on the morphological and cultural characteristics. Leaf spots similar to the original anthracnose symptoms were induced on the host leaves by artificial inoculation with the isolates of the fungus. This is the first report that C. liliacearum causes anthracnose of May lily.
Colletotrichum*
;
Cultural Characteristics
;
Fungi
;
Korea
;
Lilium*
;
Plants
7.A novel pathogenic Colletotrichum species for rhizome rot disease of Polygonatum kingianum.
Wei-Si MA ; Lan-Ping GUO ; Xin WANG ; Tie-Lin WANG ; Shi-Wu YAN ; Hang JIN ; Zhi-Hui ZHANG ; Bin YANG
China Journal of Chinese Materia Medica 2021;46(21):5606-5613
Rhizome rot disease is one of the main disease of planted Polygonatum kingianum. In this study, six strains of pathogenic fungus was isolated from P. kingianum samples with rhizome rot disease collected from six counties in Yunnan province. Its pathogenicity was confirmed by inoculation to healthy P. kingianum rhizome according to Koch's postulates. The colonies of the isolated fungi on potato dextrose agar(PDA) were orange with abundant crescentic conidia which were eseptate with a mean size of 19. 3-24. 9 μm×5. 2-5. 9 μm and a L/W ratio of 3. 4-4. 5. There was an oil ball in the center of the conidium. It's easy to see setae on PDA colony.The phylogenetic tree based on ITS, GAPDH, CHS-1, HIS3, ACT, and TUB2 sequences by maximum likelihood(ML) method indicated that the pathogenic fungus for P. kingianum rhizome rot disease was clustered into the clade of Colletotrichum spaethianum species complex, and was close to C. spaethianum. However, there were some differences in morphological and genetic characteristics between the pathogenic fungus and C. spaethianum. Therefore, the pathogenic fungus for rhizome rot disease of P. kingianum was identified as a new Colletotrichum species named C. kingianum. The disease spreads primarily due to the plantation of infected seedlings of P. kingianum. It is necessary to choose healthy seedlings and take rigorous disinfection measures for the disease prevention.
China
;
Colletotrichum/genetics*
;
Phylogeny
;
Polygonatum
;
Rhizome
8.Optimization of hydroxylating DHEA to 7alpha,15alpha-diOH-DHEA by compound mutation and fermentation optimization.
Chuanpeng LI ; Hui LI ; Yan WU ; Heng LI ; Rujin ZHANG ; Zhengbin ZHANG ; Jinsong SHI ; Zhenghong XU
Chinese Journal of Biotechnology 2014;30(1):147-156
Combined with method of ketoconazole resistance screening, a 7alpha,15alpha-diOH-DHEA high-producing mutant Colletotrichum lini ST-1 was obtained by compound mutation of NTG and low energy N+ ion beam implantation. With the substrate concentration of 10 g/L DHEA, the molar yield of 7alpha,15alpha-diOH-DHEA reached 34.2%, increased by 46.2% than that of the original strain. Then we optimized the medium. First, Plackett-Burman design was used to evaluate the effects of medium components on molar yield of the product. Results show that glucose, yeast extract and MgSO4 x 7H2O were the important parameters for the biotransformation process. Subsequently, the path of steepest ascent was used to approach the optimal levels. To obtain the optimal levels, central composite design and response surface analysis were carried out. The optimal medium was as follows (g/L): glucose 26.34, yeast extract 12.15, corn flour 3.00, FeSO4 x 7H2O 0.015, MgSO4 x 7H2O 0.14, KH2PO4 0.90. Under the optimal conditions, the molar yield of 7alpha,15alpha-diOH-DHEA reached 49.3%, which was 44.2% higher than that of using the medium before optimization.
Biotransformation
;
Colletotrichum
;
metabolism
;
Dehydroepiandrosterone
;
chemistry
;
Fermentation
;
Hydroxylation
;
Industrial Microbiology
;
Mutation
9.Systemic Resistance and Expression of the Pathogenesis-Related Genes Mediated by the Plant Growth-Promoting Rhizobacterium Bacillus amyloliquefaciens EXTN-1 Against Anthracnose Disease in Cucumber.
Kyungseok PARK ; Il Pyung AHN ; Choong Hoe KIM
Mycobiology 2001;29(1):48-53
Plants have the ability to acquire an enhanced level of resistance to pathogen attack after being exposed to specific biotic stimuli. To obtain plant growth-promoting rhizobacteria inducing resistance against cucumber anthracnose by Colletotrichum orbiculare, more than 800 strains of rhizobacteria were screened in the greenhouse. Among these strains, Bacillus amyloliquefaciens solate EXTN-1 showed significant disease control efficacy on the plants. Induction of pathogenesis-related(PR-la) gene expression by EXTN-1 was assessed using tobacco plants transformed with PR-1a::beta-glucuronidase (GUS) construct. GUS activities of tobacco treated with EXTN-1 and salicylic acid-treated transgenic tobacco were significantly higher than those of tobacco plants with other treatments. Gene expression analyses indicated that EXTN-1 induces the accumulation of defense-related genes of tobacco. The results showed that some defense genes are expressed by the treatment with EXTN-1 suggesting the similar resistance mechanism by salicylic acid.
Bacillus*
;
Colletotrichum
;
Gene Expression
;
Plants*
;
Salicylic Acid
;
Tobacco
10.Effect of Ent-norsecurinine, an Alkaloid, on Spore Germination of Some Fungi.
Mitul GOEL ; S MAURYA ; V B PANDEY ; V P SINGH ; A K SINGH ; U P SINGH
Mycobiology 2002;30(4):225-227
The inhibitory activity of ent-norsecurinine alkaloid was evaluated against spore germination of some plant pathogenic fungi (Curvularia maculans, Curvularia species, C. palliscens, Colletotrichum gloeosporioides, Colletotrichum species, Alternaria solani, A. brassicae, Fusarium udum, Helminthosporium echinoclova and H. penniseti). It inhibited spore germination of all the test fungi. C. maculans, C. species, and C. palliscens were the most sensitive as complete inhibition of spore germination was observed at 1000 ppm. A. solani was not inhibited by this chemical.
Alternaria
;
Brassica
;
Colletotrichum
;
Fungi*
;
Fusarium
;
Germination*
;
Helminthosporium
;
Plants
;
Spores*