Chilli Anthracnose Research Articles

Colletotrichum species associated with chili anthracnose in Australia

Phylogenetic relationships were determined for 45 Colletotrichum isolates causing anthracnose disease of chili in Queensland, Australia. Initial screening based on morphology, ITS and TUB2 genes resulted in a subset of 21 isolates being chosen for further taxonomic study. Isolates in the C. acutatum complex were analysed using partial sequences of six gene regions (ITS, GAPDH, ACT, CHS‐1, TUB2 and HIS3), and in the C. gloeosporioides complex were analysed using four gene regions (ITS, TUB2, ApMat and GS). Phylogenetic analysis delineated four Colletotrichum species including C. siamense, C. simmondsii, C. queenslandicum, C. truncatum and a new Colletotrichum species, described here as C. cairnsense sp. nov. This is the first reported association of C. queenslandicum, C. simmondsii and C. siamense with chili anthracnose in Australia; these species were previously associated with anthracnose on papaya and avocado. Furthermore, the dominant species causing anthracnose of chili in Southeast Asia, C. scovillei, was not detected in Australia. Inoculations on chili fruit confirmed the pathogenicity of C. cairnsense and the other four species in the development of chili anthracnose in Australia.

First report of chilli anthracnose caused by Colletotrichum karstii in India

Chilli, Capsicum annum, is an annual herbaceous vegetable and spice grown in almost all the states of India. Anthracnose (fruit rot) of chilli caused by Colletotrichum species results in both pre- and post-harvest fruit decay with yield losses of up to 50% (Pakdeevaraporn et al., 3). The different species of Colletotrichum causing chilli anthracnose reported from India include: Colletotrichum acutatum, C. capsici, C. coccodes, C. dematium, C. gloeosporioides and C. siamense. In August 2014, chilli fruits showing typical anthracnose symptoms of sunken necrotic tissues with concentric brown black rings of acervuli were obtained from a farmer's field in Jalna, Maharashtra, India. Small pieces of necrotic tissue were examined under a microscope and spores inoculated on potato dextrose agar (PDA) containing 50 mg/l streptomycin sulphate. The plates were incubated at 28°C for 5 to 7 days and a pure culture of the Colletotrichum isolate was obtained by subculturing on fresh PDA plates. The colonies had white aerial mycelia with an orange conidial mass (Fig. 1). The colour of the colony on the reverse side was light orange. The mycelial growth rate on the PDA plate at 28°C and a 16/8 h light/dark cycle respectively, was 11 mm per day. Conidia were single celled, cylindrical with rounded base and apex. Mean length and width of conidia was 13.11 ±1.22 μm and 6.2 ±0.34 μm, respectively (Fig. 2). Molecular characterization of the Colletotrichum isolate was based on ITS rDNA and partial β-tubulin gene sequence comparisons. PCR amplification was done using the universal primer pair ITS 4/5 (ITS region of the nuclear ITS1-5.8S - ITS2 rDNA; White et al., 5) and β-tubulin gene Bt2a/b primers (Glass et al., 1). Both sequences were deposited in GenBank (Accession Nos. KX492583 and KX492584, respectively) and aligned with published sequences using MEGA version 6.0 (Tamura et al., 6), and phylogenetic analysis was done (Fig. 3). Blast searches in the NCBI database revealed that the ITS and β-tubulin gene sequences had 98% and 99% identity to Colletotrichum karstii (KT284369 and KC293650, respectively) confirming that the isolate obtained from infected chilli is C. karstii. To confirm pathogenicity, chilli fruits and seedlings were wounded with a sterile syringe and inoculated with 10 μl of a conidial suspension (c. 105 conidia/ml). Sterile water was used as a control. Inoculated fruits and seedlings were kept in a chamber at 28°C with 90% humidity. After seven days typical anthracnose symptoms were observed on chilli fruits and leaves (Fig. 4). This demonstrated that C. karstii re-isolated from symptomatic chilli fruits was able to cause anthracnose, thereby fulfilling Koch's postulates. Colletotrichum karstii as a causal agent of chilli anthracnose has been reported in Brazil (Lima et al., 2) and China (Wang et al., 4). To our knowledge, this is the first report of chilli anthracnose caused by C. karstii in India.

Chilli anthracnose (Colletotrichum spp.) disease and its management approach

Chilli is a widely consumed crop throughout the world. However, chilli anthracnose is a major constraint in chilli production leading to huge economic losses worldwide. Colletotrichum is a large genus of Ascomycete fungi, containing species that cause anthracnose diseases on a wide range of crops of economic value. This review is aimed at critically and accurately examining the taxonomic identification of Colletotrichum species by morphological and molecular approaches as well as assessing their management options. The use of appropriate integrated management practices, such as cultural, mechanical, chemical, and biological control, are important in chilli anthracnose disease prevention and control. Emphasis is laid on the use of biological control because it is cost effective and eco-friendly, and is an appropriate approach for disease management. The use of resistant cultivars is the cheapest, easiest, safest, and most effective means of controlling crop diseases. But, since no resistant cultivars of chilli have been developed and commercialized, it is very important to develop biological management strategies. Further studies leading to integrated disease management strategies need to be carried out.

Selection of entomopathogenic fungus for biological control of chili anthracnose disease caused by Colletotrichum spp.

The literature on the entomopathogenic fungi in the genus Cordyceps describing its use in the agricultural area as a biocontrol agent is limited. In this study, a total of 47 isolates of entomopathogenic fungi were isolated from dead cicada nymphs obtained from various locations in the northeast of Thailand. These isolates were primarily screened for antagonistic activity to inhibit the mycelial growth of one isolate of Colletotrichum gloeosporioides and one isolate of C. capsici. The screen revealed that five isolates of entomopathogenic fungi showed good inhibitory effects on the fungal mycelial growth and were chosen for further confirmation of their antagonistic effects against five isolates of C. gloeosporioides and five isolates of C. capsici by the dual culture method. After investigation, the isolate Cod-NB1302 had the best inhibitory effect. Moreover, the mycelium extract and culture filtrate of isolate Cod-NB1302 also had inhibitory effects on the mycelial growth and conidial germination of all isolates of plant pathogenic Colletotrichum spp. under in vitro conditions. Interestingly, the mycelium extract and culture filtrate effectively reduced the size of the disease lesion and disease severity on chili fruits after inoculation with the plant pathogenic fungi. However, the mycelium extract exhibited greater antifungal activity than the culture filtrate. Finally, the isolate Cod-NB1302 was identified as Ophiocordyceps sobolifera based on the sequence of three ribosomal nuclear DNA genes and two protein-coding genes. These findings suggest that the isolate Cod-NB1302 is a potential candidate, with antagonistic activity, for use as a source of antifungal agents to control anthracnose disease caused by the plant pathogenic Colletotrichum spp.

Tagging SSR Markers Associated with Genomic Regions Controlling Anthracnose Resistance in Chilli (Capsicum baccatum L.)

Tagging SSR Markers Associated with Genomic Regions Controlling Anthracnose Resistance in Chilli (Capsicum baccatum L.) Anthracnose, caused by Colletotrichum spp. is a serious pre- and post-harvest disease in chilli (Capsicum annuum L.) which is a remunerative spice-cum-cash crop of the India. An attempt was made to tag genomic regions controlling anthracnose resistance using reported microsatellite markers.Out of 60 polymorphic SSR markers screened, only four differentiated the individual constituents of resistant and susceptible bulks. Of these four, only one (HpmsE 081) was found associated with genomic regions controlling anthracnose resistance. However, the association was weak as suggested by low contribution of the marker towards the variance of response to anthracnose disease in terms of lesion size...

English

Anthracnose of chilli caused by Colletotrichum capsici is a serious disease affecting the yield and quality of fruits. The efficacy of fish compost against chilli fruit rot was assessed in comparison with other compost. Green house study was conducted to study the disease control by application of fish compost, farm yard manure, neem cake, mahua cake, sheep manure, paddy husk, press mud, poultry manure, coir pith compost and groundnut cake. Application of fish compost of 12.5 ton/ha recorded the maximum disease incidence and increased the fruit yield when compared to control.   Key words: Colletotrichum capsici, Capsicum annuum L., fish compost. &nbsp

Evaluation of Bacillus subtilis (JN032305) biofungicide to control chilli anthracnose in pot controlled conditions

Colletotrichum gloeosporioides (Penz.) causing anthracnose is a potent pathogen of chilli resulting in significant yield loss. The in vitro root colonisation study showed an increase in root bacterial count by 10 × 105 colony forming units/cm root for Bacillus subtilis after 15 days of germination. Population level of the antagonist was stable in talc till the 180th day (30°C – 1.6 × 108; 4°C – 1.9 × 108) and in lignite till the 150th day (30°C – 1.5 × 108; 4°C – 1.3 × 108). Combined application of B. subtilis and carbendazim enhanced all biometric parameters with reduction in disease incidence. Soil, seed, root dip and foliar spray treatment significantly enhanced the growth parameters of chilli in B. subtilis inoculated treatments in comparison to the untreated control. Seed application resulted in highest plant fresh weight (76.84 g) and dry weight (34.17 g) compared to the untreated control (50 g and 21 g fresh and dry weight, respectively). Highest plant height ranging from 70 cm (soil application) to 77 cm (dip treatment) with Bacillus inoculation was comparable with carbendazim treatment (61 cm with soil application) and 78 cm (dip treatment) and significantly higher than the untreated control (58.2 cm with soil and 61 cm with application, respectively). Dip treatment resulted in significant increase in root length with B. subtilis (33 cm) and carbendazim (32.5 cm) in comparison to untreated control (15 cm). Co-inoculation of pathogen with B. subtilis (singly and with carbendazim) not only reduced the disease incidence but also improved all the biometric parameters in comparison to challenge inoculation. Root dip application was effective in promoting growth while seed application was effective in disease control.

Antimicrobial Activity of <i>Ramalina conduplicans</i> Vain. (Ramalinaceae)

The members of the genus Ramalina (Ramalinaceae) are fruticose lichens growing on various types of substrata. The present study was conducted with an aim of determining antimicrobial activity of Ramalina conduplicans Vain. The powdered lichen material was extracted sequentially using petroleum ether, ethyl acetate and ethanol. The solvent extracts were screened for antibacterial activity by Agar well diffusion assay against 15 bacteria which included reference strains and isolates from burn, dental caries and urinary tract infections. Poisoned food technique was performed to determine antifungal effect of solvent extracts against fungal isolates from anthracnose of chilli, foot rot of finger millet and mouldy grains of sorghum. Usnic acid, Salazinic acid and Sekikaic acid were detected in the lichen. The solvent extracts were shown to exhibit dose dependent inhibitory activity against test bacteria. Ethyl acetate extract inhibited reference bacterial strains to higher extent. Among solvent extracts, only ethanol extract inhibited all urinary tract bacteria. S. aureus isolates from burn were inhibited to higher extent when compared to S. mutans isolates from dental caries. The solvent extracts exhibited varied inhibitory activity against test fungi. Ethyl acetate extract inhibited Alternaria sp., Aspergillus flavus and Sclerotium rolfsii to higher extent while Colletotrichum capsici and Helminthosporium sp. were inhibited to higher extent by petroleum ether and ethanol extract respectively. The observed inhibitory potential of solvent extracts of R. conduplicans could be ascribed to the presence of secondary metabolites. The lichen can be used in the treatment of bacterial infections and to manage plant pathogenic fungi.Keywords: i Antimicrobial Agar well diffusion Poisoned food technique

Safety Assessment and Bioefficacy of Fluopyram 20 %+Tebuconazole 20 %-40 SC in Chilli, Capsicum annum L. Against Anthracnose Disease

The present paper reports the in vitro and in vivo bioefficacy of different doses of a combination of fungicide, fluopyram 20 %+tebuconazole 20 %-40 SC against anthracnose disease of chilli (Capsicum annuum L.) and their pre-harvest intervals pertaining to two different application rates. In vitro bioefficacy studies revealed the best control (79.3 %) at 250 mg kg−1 against 68.4 % control under field conditions. A sample preparation method based on ethyl acetate extraction and estimation by LC–MS multiple reaction monitoring was validated in chilli fruits. Residue dissipation studies were conducted in field at single and double doses. The residues of both fluopyram and tebuconazole on all the sampling days were below the maximum residue limit (European Union) and maximum permissible intake estimated on the basis of the prescribed acceptable daily intakes. The combined bioefficacy and residue dynamics information will support label-claim of this combination of fungicide for the management of anthracnose in chilli and facilitate its inclusion in good agricultural package of practices.

English

In the present investigation, four different composts were obtained from Supa Biotech (P) Ltd., Muketshwar and LRC, GBPUAT, Pantnagar, India. The highest actinomycetes community was obtained from CPP compost (67.18%), LRC (15.62%), CM (12.5 %) and VE (4.6%). A total of 48 actinomycetes isolated and examined, exhibited ability to degrade starch, solubilize phosphate, produce catalase and siderophores. Isolated actinomycetes strains were checked for their antagonistic potential against seed and soil borne plant pathogens: Fusarium oxysporum (Wilt), Colletotrichum truncatum (Anthracnose in soyabean), Colletotrichum capsici (Anthracnose in chilli) and Helminthosporium oryzae (Brown spot in rice). It restricted mycelium growth of all four pathogens: H. oryzae (61.53%), F. oxysporum (57.5%), C. truncatum (54.05%) and C. capsici (50%) under in vitro condition. A greenhouse study was performed to evaluate efficiency of CPP-53 for controlling disease incidence by F. oxysporum in tomato plants. Out of the four treatments in this experiment, significantly lowest disease severity and higher plant vigour was recorded when CPP-53 was inoculated as compared to the control plants. Observation proved the potential of strain CPP-53 under in vitro condition and as an amendment in soil leading to suppression of pathogenic effect and efficient biocontrol agent. 23S rDNA region of actinomycetes strains were sequenced and the most potent one, CPP-53 has 98% similarity with Streptomyces flavofuscus.   Key words: Siderophore production, wilt, disease severity, Streptomyces flavofuscus, 23S rDNA, biocontrol.&nbsp

Antimicrobial and Radical Scavenging Activity of <i>Memecylon malabaricum</i (C.B. Clarke) Cogn. and <i>Memecylon talboltianum</i> Brandis

The present study was conducted to determine antimicrobial and radical scavenging potential of extract of two species of the genus Memecylon (Melastomataceae) viz., M. malabaricum (C.B. Clarke) Cogn. and M. talboltianum Brandis. The shade dried leaf materials of both Memecylon species were extracted using methanol. Antibacterial activity of leaf extracts was evaluated against five drug resistant uropathogenic bacteria by Agar well diffusion assay. Antifungal activity of leaf extracts was tested on the basis of mycelial growth inhibition of Colletotrichum capsici (isolated from anthracnose of chilli). Radical scavenging activity of extracts was determined by performing DPPH free radical scavenging activity. Total phenolic content of extracts was estimated by Folin-Ciocalteau reagent method. The extracts were subjected to preliminary phytochemical analysis to detect the presence of phytoconstituents. Among extracts, extract of M. malabaricum inhibited all test bacteria and inhibitory potential was marked against Gram positive bacteria than Gram negative bacteria. C. capsici was highly susceptible to extract of M. malabaricum when compared to extract of M. talboltianum. Overall, extract of M. malabaricum displayed marked antimicrobial activity than extract of M. talboltianum. Extract of M. malabaricum scavenged DPPH radicals more efficiently (IC50 6.26μg/ml) when compared to extract of M. talboltianum (IC50 43.80μg/ml). The content of total phenolics was also high in leaf extract of M. malabaricum (112μg GAE/mg) than that of M. talboltianum (28μg GAE/mg). Preliminary phytochemical analysis of leaf extracts revealed the presence of flavonoids, tannins, saponins and glycosides in both extracts. The antimicrobial and radical scavenging activity of leaf extracts could be ascribed to the presence of phytochemicals mainly phenolic compounds. These plants appear to be potential candidates for control of anthracnose disease of chilli and for development of agents active against drug resistant uropathogens and oxidative damage.Keywords: Memecylon; Antimicrobial; Agar well diffusion; Poisoned food technique; Antioxidant; DPPH

Molecular, phenotypic and pathogenic variability in Colletotrichum isolates of subtropical region in north-eastern India, causing fruit rot of chillies.

To study the genetic variability and population structure of Colletotrichum species found to be associated with anthracnose of chilli in the north-eastern region of India. Twenty-three Colletotrichum isolates were obtained from infected chilli fruits and leaves from the chilli growing regions of north-eastern Uttar Pradesh, India, identified as Colletotrichum capsici and Colletotrichum acutatum using species-specific primers. Genetic variability among the isolates was analysed using RAPD and ISSR markers. The RAPD marker efficiently grouped the isolates at species level, while ISSR marker was effective in separating the isolates based on geographical origin. In vitro pathogenic test revealed the inability of C.acutatum isolates to infect unripe fruits, while C.capsici isolates were found to infect both ripe and unripe fruits at disease severity scale 7-9. Growth rate on different media was recorded to cross-confirm the classification of isolates, which clearly grouped the two species into distinct group on PCA plot. Two species, viz. C.capsici and C.acutatum, prevalent in the region were found to infect the fruits at postripening stage. The present study proposes the implementation of management strategies at postripening stages of the crop to control the spread of disease, thereby leading to increment in production of chilli in the given region.

Inhibitory Effect of Some Plants of Western Ghats of Karnataka against Colletotrichum capsici

Anthracnose is a serious disease of chilli which results in major crop loss. Species of Colletotrichum are the causative agents of chilli anthracnose. In the present study, we investigated the inhibitory effect of a total of 50 extracts from 35 plants (belonging to 23 botanical families) of Western Ghats of Shivamogga district, Karnataka, India. The powdered plant materials were extracted using methanol. The methanol extracts were screened for antifungal activity by Poisoned food technique against Colletotrichum capsici isolated from anthracnose of chilli. All extracts were effective in inhibiting the growth of C. capsici but to a varied extent (16 to 74% inhibition). The mycelial growth of fungus was found to be reduced on poisoned plates when compared to control plate. Marked inhibitory efficacy was observed in case of leaf extract of Maesa indica (74.19%) followed by leaf extract of Pimenta dioica (70.96%). Least inhibition of the fungus was shown by leaf extract of Persea macrantha (16.13%). The extent of inhibition of the fungus by other extracts ranged between 20 to 70%. In conclusion, the plants selected in this study appear promising as natural antifungal agents. Further field studies are to be conducted to determine the possible application of these plants in the control of chilli anthracnose. Keywords : Western Ghats; Antifungal activity; Poisoned food technique; Colletotrichum capsici; Anthracnose of chilli

BIOCONTROL POTENTIAL OF PARMOTREMA SPECIES AGAINST COLLETOTRICHUM CAPSICI ISOLATED FROM ANTHRACNOSE OF CHILLI

Chilli is an important commercial crop and is consumed as spice as well as vegetable. Colletotrichum capsici is an important fungal pathogen causing anthracnose in chilli. The objective of the present study was to determine inhibitory activity against C. capsici of extracts of three foliose macrolichen species of the genus Parmotrema viz ., P. tinctorum , P. grayanum and P. praesorediosum from Western Gh ats of Karnataka, India. The antifungal effect was checked in terms of mycelial growth inhibition by Poisoned food technique. The spore suspension of C. capsici was inoculated on the centre of Potato dextrose agar plates (control and poisoned). The colony diameter of fungus in control and poisoned plates was recorded on 5 th day of incubation. The lichen extracts caused marked inhibition of test fungus as revealed by reduced colony diameter of test fungus in poisoned plates. Among lichens, P. tinctorum showe d potent inhibitory activity and caused > 50 % of inhibition of test fungus. The lichens of the present study appeared promising as bio control agents against C. capsici .

Infra-specific diversity of Colletotrichum truncatum associated with chilli anthracnose in India based on microsatellite marker analysis

Colletotrichum truncatum is a fungal species associated with anthracnose disease in many economically important crops within the plant families Fabaceae and Solanaceae. Understanding the degree of genetic diversity within C. truncatum population will provide insights into the ability of this species to evolve in response to environmental conditions, and thus be helpful in designing effective control strategies for this pathogen. In this study, microsatellite markers from 27 loci were used to investigate the genetic diversity and population structure among 99 isolates of C. truncatum from India. All the loci (100%) were polymorphic and a total of 140 different alleles were amplified. Six distinct groups were obtained based on unweighted pair group method with arithmetical average cluster analysis. The isolates belonging to Group V showed the highest level of genetic diversity and a broad host range. Analysis of molecular variance analysis showed that the variation occurs mostly within groups. Microsatellite markers-based genetic diversity estimation revealed high diversity among C. truncatum isolates from India.

Inhibitory Effect of Cow Urine against <i>Colletotrichum capsici</i> Isolated from Anthracnose of Chilli (<i>Capsicum annuum L.</i>)

Cow urine has got several applications in agriculture. It is shown to possess inhibitory activity against many phytopathogenic fungi and bacteria. Among various diseases of Chilli, anthracnose is the most important disease which results in drastic reduction in yield. The present study was conducted with an aim to determine antifungal efficacy of cow urine against Colletotrichum capsici isolated from anthracnose of chilli (Capsicum annuum L.). Poisoned food technique was employed to determine antifungal activity of different concentrations of cow urine (5, 10 and 15%). Cow urine was found to display concentration dependent inhibitory activity against fungal growth. An inhibition of >50% was observed at 5% concentration. In conclusion, the use of cow urine can be the costeffective and eco-friendly approach for controlling anthracnose in chilli.

Irradiated Oligochitosan against Colletotrichum Gloeosporioides in Chili

This study aimed to prepare oligochitosan by gamma radiation. Irradiated oligochitosan was prepared in solid state in air at room temperature. The molecular weight of irradiated oligochitosan in relation to different irradiation doses were analyzed and assess the efficiency of irradiated oligochitosan on Colletotrichum gloeosporioides (C. gloeosporioides) causing chili anthracnose in Thailand. The viscosity average molecular weight of irradiated oligochitosan was carried out by using Ubbelohde viscosmeter. Gamma irradiation led to significant reduction of the viscosity-average molecular weight (Mv) of chitosan. The apparent Mv of oligochitosan decreased with increasing radiation dose. Lactic acid was used as a solvent instead of acetic acid which is a common solvent due to the inhibition ability of acetic acid against C. gloeosporioides. Potato Dextrose Agar (PDA) incorporated with oligochitosan at different concentrations (0.001, 0.005, 0.01, 0.05, 0.1, 0.5 or 1.0%) was used as treatments for in vitro tests. The result shows that PDA mixed with 0.05 – 1% irradiated oligochitosan were inhibited or retarded the growth of C. gloeosporioides.

Efficacy of Propolis and Cinnamon Oil Coating in Controlling Post-Harvest Anthracnose and Quality of Chilli (Capsicum annuum L.) during Cold Storage

Brazilian green propolis extract (PP) and cinnamon oil (CM) as edible coatings can be used to maximize chilli shelf life due to their antifungal properties. Antifungal effects and quality control of 5 % PP, 0.1 % CM and the combination of PP and CM incorporated with 5 % gum arabic (GA) as base coating were investigated in vitro as well as in vivo. Coated chillies were stored in cold storage of 13 ± 2 °C (80–90 % relative humidity (RH)) for 28 days and 5 days at simulated marketing conditions (25 ± 2 °C, 60–70 % RH). Study revealed that PP and CM alone had fungicidal effect against Colletotrichum capsici, causal organisms of chilli anthracnose. However, combined treatment of PP and CM showed the most promising results against C. capsici with 100 % inhibition on mycelia growth and spore germination. In vivo studies revealed that combined treatment of PP and CM showed a significantly (p < 0.05) lower disease incidence (14 %) and severity score (1.5) after 33 days of storage, as well as a significant delay in the changes of weight loss, firmness, peel colour and soluble solids concentration compared with other treatments. It could be concluded that 5 % PP combined with 0.1 % CM incorporated with 5 % base coating of GA is an effective bio-fungicide for postharvest anthracnose control and retaining the quality of chilli.

Colletotrichum fructicola and C. siamense are involved in chilli anthracnose in India

Chilli anthracnose is a major problem in India and worldwide. In this study, we investigated the phylogenetic relationships of 52 fungal isolates associated with chilli anthracnose in southern India. All the 52 isolates were sequenced for partial ITS/5.8S rRNA and glyceraldehyde-3-phosphate dehydrogenase (gapdh) genes and showed affinities with Colletotrichum siamense and C. fructicola within Colletotrichum. gloeosporioides species complex. Further, a reduced subset of 17 selected isolates was made and in a maximum parsimony analysis of a multigene data-set including partial ITS/5.8S rRNA, actin (act), calmodulin (cal), chitin synthase (chs1), gapdh and β-tubulin (tub2) gene sequence data, these fungal isolates clustered with the type strain of C. fructicola, except for strain MTCC 3439 that showed phylogenetic affinities with C. siamense. The pathogenicity tests involving two representative isolates: UASB-Cg-14 and MTCC 3439, confirmed the involvement of C. fructicola and C. siamense in the development of disease symptoms on fresh chilli fruits. This is the first report of the association of C. fructicola and C. siamense in causing chilli anthracnose in India.

Biological control of anthracnose of chilli with rhizosphere and rhizoplane fungal isolates from grasses

The fungal species from rhizosphere and rhizoplane of perennial grasses of the Western Ghats of India were studied for their pathogenicity, antagonism in vitro, substrate and root colonization abilities, rhizosphere competence, growth in different soil pH and inoculum shelf-life. Out of 138 non-pathogenic fungal isolates tested, 85 were antagonistic in vitro to chilli anthracnose pathogen Colletotrichum capsici. Fifteen isolates with >60% inhibition zone to pathogen culture had saprophytic and root and rhizosphere colonization abilities. The sorghum grain inocula of test antagonistic fungi- Fusarium oxysporum, Chaetomium globosum and Trichoderma harzianum had the shelf-life of 90 days at 20 ± 2 °C and required optimum soil pH of 6.5. The above fungal isolates when tested for biocontrol of anthracnose disease in greenhouse and field caused reduction in seedling mortality and decreased disease incidence and severity at various plant growth stages and significant reduction in chilli fruit and seed infection. The test antagonistic fungi promoted seedling and mature plant growth and increased fruit and seed yield. Populations of these antagonistic fungi were fairly high in chilli rhizosphere at harvest. The present study indicated that antagonistic fungi from grass rhizosphere and rhizoplane could be used to control anthracnose and promote plant growth, and increase yield of chilli in field.