Anthracnose Disease Incidence Research Articles

Studies on the Incidence of Anthracnose Disease in Different Varieties of Mango (Mangifera Indica L.) and it's in Vitro Biocontrol Measures

Anthracnose of mango caused by Colletotrichum gloeosporioides) is a very serious disease. Leaves, panicles, immature and mature fruits of mango are infected and damaged by this disease. The symptoms of this disease on infected parts were noted. The incidence of disease on leaves was studied on fourteen varieties of mango viz. Himsagar, Dashehari, Vanraj, Farnandin, Mulgoa, Bombai, Kishanbhog, Bangalora, Alphanso, Langra, Mallika, Zardalu, Chausa and Suvarnrekha. In all the varieties the incidence of anthracnose ranged from 1 - 15 per cent. The disease incidence was maximum (15.00 per cent) in Kishanbhog followed by Bombai (12.00 per cent), Himsagar (9.00 per cent) and Bangalora (8.00 per cent). In contrast, the disease incidence was recorded minimum in Alphanso (1.00 per cent). Trichoderma viride and Beauveria bassiana were applied against Colletotrichum gloeosporioides in vitro and their antagonistic activity were recorded.

Identification and characterization of a new Bacillus atrophaeus strain B5 as biocontrol agent of postharvest anthracnose disease in soursop (Annona muricata) and avocado (Persea americana)

Anthracnose is a fungal disease caused by Colletotrichum species that is detrimental to numerous fruit, including soursop and avocado. The use of fungicides to maintain the high quality of fruit creates a potential health risk. One alternative to this problem is the biological control, which has been applied successfully during postharvest. The Bacillus species are one of the most studied biological agents against postharvest pathogens because accomplish their biocontrol performance by producing a variety of metabolites. In this study, we evaluated the activity of metabolites contained in the cell free supernatant, obtained from Bacillus strain B5 culture, against micelial growth and spore germination of two virulent strains of C. gloeosporioides isolated from soursop and avocado. On the basis of 16S rDNA gene sequence analysis, this strain was identified as Bacillus atrophaeus. A preventive treatment using cell free supernatant, reduced severity and incidence of anthracnose disease on harvested soursop and avocado fruit. B. atrophaeus strain B5 harbors genes involved in the production of antibiotics such as surfactin, bacillomycin and iturin, which could be contributing to the efficiency of the preventive treatment during postharvest. The antagonistic role of metabolites contained in the cell free supernatant against anthracnose disease, provide a new approach by which to attack this problem and can help reduce the use of chemical pesticides, environmental pollution, leading to the safer fruit preservation.

Control of anthracnose disease via increased activity of defence related enzymes in ‘Hass’ avocado fruit treated with methyl jasmonate and methyl salicylate

Development of anthracnose disease caused by Colletotrichum gloeosporioides Penz. is one of the major issues within the avocado supply chain. Exposure to methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours at 10 and 100µmoll−1 was investigated as an alternative solution to commercial fungicide – prochloraz® that is currently being used by the industry. The incidence of anthracnose disease was found to be significantly reduced in ‘Hass’ avocado fruit treated with MeJA or MeSA vapours, especially at 100μmoll−1. The mechanism involved enhanced activity of defence related enzymes, i.e. chitinase, β-1,3-glucanase and PAL, and higher content of epicatechin.

PERFORMANCE EVALUATION OF SOME CHILI PEPPER (CAPSICUM SPP) GENOTYPES FOR ANTHRACNOSE (COLLETOTRICHUM CAPSICI (SYD)) RESISTANCE IN SNNP REGION OF ETHIOPIA

Ten chili (Capsicum spp) varieties were screened for resistance to anthracnose (Colletotrichum capsici) in field experiments at two locations, Alaba and Maraqo. Starting seven days after transplanting, plants in each plot were monitored for diseases symptoms and infections. Data on incidence and severity of anthracnose were collected. Besides, the disease progress curve (AUDPC) and yield components were recorded before and after harvest. The data showed that the incidence of anthracnose disease and yield parameters such as dry fruit weight per plant, number of fruit per plant, pulp weight per plant, unmarketable fruits weight per plant, fruit length and days to 50 percent maturity, differed significantly among the tested genotypes at both locations. The majority of the genotypes were rated as moderate resistant to susceptible ones and none of the genotypes was free from the disease at both locations. Total yield per plant was higher at Alaba than Maraqo. This variation is related to the level of disease intensity, which was higher at Maraqo. After thorough multi-location researches, the identified sources of resistance were recommended to be utilized in future pepper breeding programs.

English

  Mango is a highly perishable fruit and high post-harvest losses occur in Africa. In order to address this problem, 4 concentrations of Aloe vera gel (AG) (0, 25, 50 and 75%) and chitosan (1%) were tested at two temperature levels (room temperature 15-22°C and 13°C) to determine their effect on the postharvest life of mango (var.’Ngowe’). The experimental design was a 5 by 2 factorial experiment embedded in a complete randomized design with three replications. Data were recorded on titratable acidity, fruit colour, ascorbic acid and anthracnose disease incidence. The results showed that at both temperatures 50 and 75% Aloe concentrations significantly increased the shelf life evidenced by reduced decrease in titratable acidity. Fruit colour and ascorbic acid were also maintained for longer periods in these treatments. Findings of this study demonstrate the potential of using Aloe vera gel at 50% as a coating for improved postharvest shelf life and maintaining quality of mango fruits hence reduced postharvest losses.   Key words: Aloe vera gel, postharvest shelf life, mango.

Antimicrobial activity of chitosan enriched with lemongrass oil against anthracnose of bell pepper

Abstract Essential oils have been investigated as potential additives for polysaccharide based coatings. In this study the effectiveness of combining lemongrass essential oil with chitosan as an edible coating for bell pepper was examined. Lemongrass essential oil at concentrations of 0.5% and 1.0% was incorporated into 0.5% and 1.0% chitosan solution and evaluated as a means of controlling anthracnose of bell pepper in vitro and in vivo. Fungal growth was effectively controlled by 0.5% and 1.0% EO in vitro. The application of 1.0% chitosan was determined as an effective concentration, and was used in subsequent in vivo analysis as a base coating for maintaining the safety and quality of fresh bell peppers stored at room temperature for 21 days. EO was found to be less effective in vivo, however the combination of EO with CH did enhance the antimicrobial activity of the coating. Quality of the fruits, as determined by weight loss, firmness, colour, SSC and TA, was maintained throughout the storage by the chitosan coating solely and in combination with EO. The in vivo results demonstrated that, as an edible coating, the application of 1.0CH + 0.5 EO was significantly better at maintaining the fruit quality, however, with the anthracnose disease incidence results in consideration, chitosan individually was more effective in the extension of fruit shelf life.

Anthracnose of betel vine and its in vitro management

The incidence of anthracnose disease was observed lowest in December (10.87%) and highest in July (80.50%) at the three selected betel vine fields of Shalon village in Moulvibazar district. The young stems were found more prone to attack than the old ones. Pathogenicity test showed Colletotrichum dematium and C. gloeosporioides produced characteristic disease symptoms on betel stems. Among them C. dematium is a new document as a pathogen of anthracnose of betel vine. Out of five fungicides, complete inhibition of both the pathogens in vitro occurred with corozole EC (25% propiconazole), folicur EC (25% tebuconazole) and trooper WP (75% tricyclazole). Among the four antagonistic fungi, Penicillium sp. showed more antagonistic potentiality against the pathogens. DOI: http://dx.doi.org/10.3329/dujbs.v23i2.20092 Dhaka Univ. J. Biol. Sci. 23(2): 127-133, 2014

TECHNOLOGY OF ANTHRACNOSE CONTROL ON INCREASING STRAWBERRY PLANTLETS

Strawberry anthracnose is caused by several species of fungi and C. gloeosporioides is the major fungus in Zhejiang province of China. It is difficult to raise strawberry plantlets at the main rain season. In this paper we describe a useful technology to raise strawberry plantlets in high temperature and humidity environments. (1) Use of disease-free planting material. Disinfectants like Cabrio and Mancozeb also can be used to sterilize the mother plants. (2) Soil disinfection and sterilization. Solar soil disinfection technology is a cost-effective method. Soil disinfectants such as chlorine dioxide and trichloroisocyanuric acid can also be used in the course of solarization. (3) Rain-shelter and shading cultivation. This measure can keep the plantlets free of rain. The most suitable sunshade net provides 80% shade. Under this cultivation, anthracnose disease incidence was reduced to 6.2% while the control was 61.7%. (4) Use of fungicide combinations. The intensified fungicides reduced the disease incidence to 8.7%, significantly lower than those of a single fungicide treatment. It's better to use plant growth retardants in order to grow fine plantlets by early July. Plantlet quality was increased significantly compared with the control.

Cerebroside mediated elicitation of defense response in chilli (Capsicum annuum L.) against Colletotrichum capsici infection

Enhancing the host resistance by using naturally occurring elicitors derived from pathogenic organisms is emerging as an ecofriendly approach in plant disease management. Cerebrosides, categorized as glycosphingolipids, were isolated and partially purified from the wilt causing fungus (Fusarium oxysporum f. sp. lycopersici). Cerebroside treatment significantly reduced the anthracnose disease incidence under greenhouse conditions. Cerebroside elicitors were found to stimulate the early H2O2 accumulation followed by the production of plant defense-related enzymes such as Phenylalanine ammonia lyase (PAL), Peroxidase (POX), Polyphenol oxidase (PPO), and Lipoxygenase (LOX) when applied to chilli (Capsicum annuum L.) plants by spray treatment and also induced the accumulation of capsidiol. Defense-related enzyme activities were increased by the elicitor treatment and an high level in activity was maintained during the experimental period. Under greenhouse conditions, the cerebroside elicitors effectively protected chilli plants against infection by anthracnose causing organism, Colletotrichum capsici.

Mechanisms governing the responses to anthracnose pathogen in Juglans spp.

Juglans nigra and Juglans regia are two highly economically important species for wood and fruit production that are susceptible to anthracnose caused by Gnomonia leptostyla. The identification of genotypes resistant to anthracnose could represent a valid alternative to agronomic and chemical management. In this study, we analyzed 72 walnut genotypes that showed a variety of resistance phenotypes in response to natural infection. According to the disease severity rating and microsatellite fingerprinting analysis, these genotypes were divided into three main groups: (40) J. nigra resistant, (1) J. nigra susceptible, and (31) J. regia susceptible. Data on leaf emergence rates and analysis of in vivo pathogenicity indicated that the incidence of anthracnose disease in the field might be partially conditioned by two key factors: the age and/or availability of susceptible leaves during the primary infection of fungus (avoidance by late flushing) and partial host resistance. NBS profiling approach, based on PCR amplification with an adapter primer for an adapter matching a restriction enzyme site and a degenerate primer targeting the conserved motifs present in the NBS domain of NBS-LRR genes, was applied. The results revealed the presence of a candidate marker that correlated to a reduction in anthracnose incidence in 72 walnut genotypes.

BIOLOGICAL CONTROL OF ANTHRACNOSE WITH TRICHODERMA IN STRAWBERRY FIELDS

Experiments were conducted in a strawberry farm located in Moguer (Huelva, SW Spain) from October to May for three consecutive growing seasons. The objective of this research was to evaluate the use of Trichoderma spp. for biocontrol of anthracnose in large-scale strawberry field experiments. Trichoderma spp. were applied via drip irrigation and dip, by addition to the soil 7-days before planting (10 conidia/m 2 ) , and by dipping strawberry roots in a suspension of Trichoderma (10 6 conidia/ml) prior to planting. A randomised complete block design with four replications was used. Each plot was 12.5 × 3.3 m and had three raised beds. Plants from the nursery were examined during October to detect latent infections of Colletotrichum spp. The highest percentage of anthracnose-infected transplants was detected in the second year. Crown infections were initiated in the nursery but were not apparent until after plants were set in production fields. The fungus continued to grow in infected plants, which later died suddenly following warm weather in the fall and the following spring. Trichoderma applications reduced anthracnose disease incidence and, consequently, plant mortality. This work contributes to the development and optimization of biocontrol with Trichoderma as alternatives to the traditional use of chemicals in strawberry production.

Effects of Calcium and Chitosan Treatments on Controlling Anthracnose and Postharvest Quality of Papaya (Carica papaya L.)

This study was conducted to evaluate the in vitro fungicidal effects of calcium and chitosan on Colletotrichum gloeosporioides and to as well determine their effects on storage life and quality of papaya. Potato Dextrose Agar (PDA) incorporated with calcium at different concentrations (1.5, 2.5 or 3.5%) or in combination with chitosan at 0.75% or chitosan alone were used as treatments for in vitro tests. Uncorporated treatments with PDA and untreated fruits as control used on papaya fruits for storage life and quality evolutions. Chitosan had the greatest effect against Colletotrichum gloeosporioides in both in vitro and in disease incidence (%) on papaya fruits compared to calcium treatment and as well as control. Calcium reduced spores germination significantly as calcium concentrations increased from 2.5 to 3.5%, compared to the 1.5% and control treatments. However, it did not show any fungicidal effects on mycelial growth. The combination of 2.5% calcium with chitosan 0.75% completely inhibited spore germinations and significantly inhibited mycelia growth compared to calcium individual treatments and as well as control. Anthracnose disease incidence (%) was significantly controlled (5.6%) using calcium at 2.5% combined with chitosan compared with the other treatments. This demonstrated the best effect on controlling anthracnose disease incidence for papaya fruits. Moreover, this treatment proved able to extend the storage life of papaya fruits up to 33 days of storage life while maintaining valuable attributes of quality.

Management, Survival Strategies, and Host Range of Colletotrichum acutatum on Strawberry

Colletotrichum spp. are broad-range pathogens, meaning that many species can infect a single host and a single species can infect diverse hosts. For example, Colletotrichum acutatum J.H. Simmonds affects a wide range of crops, causing disease symptoms on apple, almond, anemone, citrus, lupin, peach, pecan, strawberry, and others, whereas Colletotrichum gloeosporioides Penz. (Penz. & Sacc.) can affect many of the previous hosts as well. Anthracnose is one of the major fungal diseases of strawberry occurring worldwide. In Israel, the disease is caused primarily by the species C. acutatum. The pathogen causes irregular leaf spot, bud rot, petiole and stolon necrosis, and black spot on fruit. The pathogen is most destructive when it causes root necrosis and crown rot, which usually kill the plants in nurseries and transplants in the field. To maintain a disease-free crop, nuclear and foundation stock material, as well as field nurseries, must be routinely monitored and tested for presence of the pathogen. Strawberry cultivation using plasticulture as an overhead cover of the crop can significantly control anthracnose disease incidence by reducing inoculum spread and infection, both in nurseries and in production fields. C. acutatum from strawberry can survive on several cultivated plant species, such as pepper, eggplant, tomato, bean, and weed species, without causing disease symptoms. This indicated that they may serve as a potential inoculum reservoir for strawberry infection between seasons. Although C. acutatum survives in soil under certain conditions, no specific resting structures have been observed indicating that the pathogen does not behave as a typical soilborne fungus.

Effect of Fertilizers on the Incidence of Anthracnose Disease, Yield and Quality of Mango

Effect of different fertilizers on the control of anthracnose disease, yield and quality of mango cv Amrapali was investigated. Application of combined fertilizers gave the highest fruit set, fruit retention and fresh fruits, therefore, produced the highest yield per plant and per hectare. The highest number of healthy fruits was found from 2nd year crop and the lowest was obtained from 1st year. The highest (8.47 t/ha) yield was obtained from 2nd year and the lowest (4.58 t/ha) was obtained from 1st year crop. Among the treatments, combined application of NPK, ZnSo4, Gypsum and Cowdung gave the highest (50.67) number of healthy fruits and the lowest (16) was obtained from untreated plant. The highest (12.41 t/ha) yield was obtained from combined application of NPK, ZnSo4, Gypsum and Cowdung and the lowest (3.88 t/ha) was obtained from untreated plant. In respect of combined effect, the highest (15.22 t/ha) yield was obtained from 2nd year x T9 treated plant and the lowest (2.95 t/ha) was found in untreated 1st year plant. Key words: Mango, fertilizers, anthracnose, yield. DOI = 10.3329/jard.v5i1.1461 J Agric Rural Dev 5(1&2), 70-78, June 2007