Screening faba beans for resistance to ascochyta fabae by. Molecular breeding for ascochyta blight resistance in. Studies on the biology and control of ascochyta fabae on fa ba bean v. Ascochyta leaf blight results in the rapid development of large irregularly shaped, strawcolored patches on kentucky bluegrass, and occasionally tall rescue and perennial ryegrass during the summer. The major ones include ascochyta blight ascochyta fabae speg. Ascochyta fabaethe causative agent of ascochyta blight and.
Ascochyta blight is currently is the most common disease of lentils in the northern hemisphere. Manual weeding is useful just to avoid spreading of the. However, lentil production is constrained by many factors including biotic stresses, majority of which are fungal diseases such as ascochyta blight ab, fusarium wilt, rust, stemphylium blight, anthracnose. Seedlings of different cultivars were tested and results compared with available field data. In this paper, attempts have been made to summarize the progress made in identifying resistance. Ascochyta blight ascochyta fabae occurs in all faba bean growing areas of western australia.
Ascochyta leaf blight symptoms of kentucky bluegrass leaf blades. You can positively identify an ascochyta leaf blight infection by examining damaged grass blades with a hand magnifying glass. The primary inoculum source that initiates disease epidemics is airborne ascospores released from fungal fruiting bodies pycnidia and perithecia on infested crop debris. Transmission of ascochyta blight from infected seed to foliar tissues is favored by cool, moist soil. High titres were obtained in shake culture but not in still culture unless the surface to volume ratio was large. A field was only considered positive for ascochyta blight if the causal pathogen was isolated from symptomatic lentil tissues collected in that field. Identification of a polyketide synthase gene responsible. It is considered that other primary sources of inoculum, sucli as host material buried in the soil, are of minor significance in the establishment of the disease. Ascochyta blight, caused by ascochyta rabiei, is a serious disease of chickpea cicer arietinum and fungicide applications are used to manage the disease in the north central plains 4. Ascochyta blight is a seedborne or residueborne disease of faba beans in western canada. Systematic mycology and microbiology laboratory invasive.
It is an important source of protein in many parts of central asia and africa. Ascochyta rabiei michael wunsch, plant pathologist north dakota state university carrington research extension center 9. It may be beneficial to utilize an integrated weed management strategy, combining both herbicides and cultural control methods. Use of metabolomics for the chemotaxonomy of legume. Histopathology of the interaction between ascochyta fabae and vicia faba. Systematic mycology and microbiology laboratory invasive fungi fact sheets ascochyta blight of broad beansdidymella fabaeascochyta fabae ascochyta blight is the most severe disease of coolseason pulses davidson and kimber, 2007. The disease is widespread in southern australia, but its severity varies considerably from crop to crop and between seasons. High resistance to both diseases was very frequently detected in vicia spp.
Ascochyta leaf blight comes on quickly, causing large brown or bleached patches in lawns when the weather is quickly alternating between very wet and very dry, but the exact environmental trigger is unknown. It occurs everywhere faba bean is grown in western canada and can be stubble or seedborne. Ascochyta definition of ascochyta by merriamwebster. The effect of four fungicide seed treatments on the control of seedborne ascochyta blight of lentil, caused by a. Lentil is relatively free from any serious infestation of insect pests except. Studies on the biology and control of ascochyta fabae on. To understand the composition of fungi associated with this disease in zhejiang. A method was developed for screening faba bean seedlings for resistance to ascochyta fabae. Although several fungicides will inhibit ascochyta growth, they can be expensive and difficult to apply. Faba beans are a poor competitor, so good weed control is essential and often the most important consideration for profitable faba bean production. In this work, we aimed to validate across generations the main quantitative trait loci qtls for ascochyta blight resistance identified in the. Turfgrass usually recovers completely after a couple of weeks. Here, we identified a polyketide synthase pks gene. Ascochyta leaf and pod spot is caused by the fungus ascochyta fabae.
While some faba bean diseases may cause little damage, other faba bean diseases can be very damaging and warrant appropriate control. Peas fill an important role as a break crop for new zealand growers, but in some situations it is not a profitable crop option. The sexual state teleomorph was first reported and described by jellis and punithalingam 1991 on overwintering v. Ascochyta leaf and pod spot is caused by ascochyta fabae. Ascochyta blight is known to occur on droughtstressed turf and also during periods of hot weather preceded by wet conditions. Gent, martha mikkelson,and jack riesselman identification and life cycle ascochyta blight is caused by the fungus ascochyta fabae f. To evaluate the effect of new fungicide management on the ascochyta blight field trial was conducted in 20 cropping season on randomized complete blocks design with three replications. Distribution of ascochyta blight in north dakota and eastern montana lentil production fields in 2011. Yield losses can be as high as 90% and losses of 3540% are common. Qtls for ascochyta blight resistance in faba bean vicia. Ascochyta pisi et f8 ascochyta fabae et a30 ascochyta rabiei. An update on genetic resistance of chickpea to ascochyta blight. Response of vicia species to ascochyta fabae and uromyces. Ascochitine was produced in culture by 18 of 19 isolates of ascochyta fabae.
Specific diseases such as leaf and pod spot ascochyta fabae in field beans and pea. Histopathology of the interaction between ascochyta fabae and. Files are available under licenses specified on their description page. Ascochyta leaf and pod spot of faba bean grains, pulses. Because the ascochyta fungus is primarily a foliar pathogen, diseased turfgrass usually recovers relatively quickly. Systematic mycology and microbiology laboratory invasive fungi fact sheets ascochyta blight of broad beansdidymella fabae ascochyta fabae ascochyta blight is the most severe disease of coolseason pulses davidson and kimber, 2007. Two controlled condition experiments were conducted to study the temperature effect on mycelial growth and. An extended period of leaf wetness is required for disease. Ascochyta blight, caused by ascochyta fabae, is an important disease of faba beans in victoria, south australia and new south wales. All structured data from the file and property namespaces is available under the creative commons cc0 license. Ascochitine is structurally similar to the wellknown mycotoxin citrinin and exhibits broadspectrum phytotoxicity and antimicrobial activities. The polyketidederived secondary metabolite ascochitine is produced by species in the didymellaceae family, including but not restricted to ascochyta species pathogens of coolseason food legumes.
Leaves of vicia faba plants naturally or artificially infected with ascochyta fabae. Studies on the control of ascochyta blight in field peas. Ascochyta leaf and pod spot of faba bean grains, pulses and. Ascochyta blight, or leaf and pod spot, of vicia faba is caused by d. Ascochyta leaf blight of lawns horticulture and home pest news. Ascochyta fabae is a major parasite of faba bean causes ascochyta blight disease. A comparison of clean seed left with ascochyta blight infected lentil seed right. It is not the same ascochyta species which infects other pulses and is specific to faba beans. Ascospores germinate and infect pea over a range of tempatures 40 to 95. Fungicides management is essential to control this disease.
Ascochyta leaf blight or spot of turfgrasses is caused by more than 80 different fungi which can cause damage to kentucky bluegrass, bentgrasses, italian and perennial ryegrasses, fescues red, meadow, sheep, and tall, redtop, and many other forage, weed, and wild grasses. Management of ascochyta blight ascochyta r abiei in. Mycosphaerella pinodes causes mycosphaerella blight. Histopathology of the interaction between ascochyta fabae. In recent years this disease has become the most important disease in chickpeas. Isolates of ascochyta fabae from faba bean vicia faba and a. Although there have been a large number of trials looking at fungicide control of ascochyta, they have. Cultural control plant seed free from the aschochyta blight pathogen. It is yield limiting in the medium and high rainfall areas of the central and southern agricultural regions. Faba bean diseases faba beans are subject to a number of diseases that can reduce yield and quality. Diseasefree seed is highly recommended in areas where faba bean is grown commercially. To manage the disease, reduce thatch by core aeration at least once a year to allow better water penetration.
Eliminate crop debris and volunteer lentil by deep tillage to reduce pathogen survival. Ascochyta blight is seedborne and infected seed is an important source of primary inoculum in the field 18, 19. This page was last edited on 17 august 2018, at 03. Clarification on host range of didymella pinodes the causal. Management of ascochyta blight of chickpea causal pathogen. Ascochyta is a genus of ascomycete fungi, containing several species that are pathogenic to plants, particularly cereal crops. Apr 12, 2016 ascochyta blight, an infection caused by a complex of ascochyta pinodes, ascochyta pinodella, ascochyta pisi, andor phoma koolunga, is a destructive disease in many field peas pisum sativum l. Breeding for host resistance is an efficient means to combat this disease. To understand the composition of fungi associated with this disease in zhejiang province, china, a total of 65 single. An update on genetic resistance of chickpea to ascochyta. Pdf etude morphologique et physiologique, lutte chimique. Identification of a polyketide synthase gene responsible for. The reasons for poor yields are not clear and probably vary markedly from site to site.
Ascochyta definition is a form genus of imperfect fungi order sphaeropsidales with hyaline 2celled pycnospores formed in pycnidia located in discolored spots in leaves, stems, or fruits. It is not the same ascochyta species which infects other pulses and is specific to faba. Ascochyta blight is an important disease of faba bean vicia faba l. Use of metabolomics for the chemotaxonomy of legumeassociated ascochyta and allied genera. Use a seed treatment registered for ascochyta control. Maximum transmission from seeds to seedlings occurs when the soil temperature is approximately 46.
With regard to incubation period, xu 46 and xu and robinson 47 noted that the median incubation period was longer at lower and higher temperatures than at intermediate temperature ranges in rose and hawthorn powdery mildew. Galway the optimum temperature for radial growth of ascochyta fabae mycelium on agar and for fungal infection of erfordia faba bean vicia faba was 20c. The fungal pathogen ascochyta lentis that causes ascochyta blight can survive in infected seed, and in previously infected lentil stubble. Pdf occurrence of didymella fabae, the teleomorph of ascochyta. Temperature affected incubation period, lesion expansion, percent leaf damage, audpc and rate of fabaee spot progress on both detached leaf and whole plant tests in faba bean. After 2 weeks of growth, the embedded slide with the fungal colony growing on the thin layer of pda about 2 mm in diameter was removed from the plate and dried for 1 h at 65c for maldi imaging analysis. Controlling ascochyta blight what to do for grass with leaf. Ascochyta fabae attacks vicia faba and can survive and reproduce in and spread from crop debris or be transported in infected seed. Controlling ascochyta blight what to do for grass with. May 10, 2017 planting clean, disease free seed is the safest method of control, although seed with up to 5% ascochyta lentis infection will not significantly affect yield as long as soil and weather conditions favor quick germination and good plant vigor. The primers amplify the internal transcribed spacer its regions of a. Introduction on infected seed occurred in australia and canada in the 1970s, and was probably the means for the pathogens original spread to countries outside southwestern asia. Conidia were collected from colonies grown on v8 agar for 16 d and stained with aniline blue. P22 peas fungicide timing products for ascochyta control.
The genus was first described in 1830 by marieanne libert, who regarded the spores as minute asci and the cell contents as spherical spore. Ascochyta blight is primarily a leaf and not a root or crown disease so it rarely causes plant mortality. Ascochyta damaged turf where spores might have been spread by the mower. The fungus was initially known in the asexual state, spreading by means of conidia produced in pycnidia.
Pdf temperature effects on cultural and morphological. Etude morphologique et physiologique, lutte chimique, polymorphisme. The amplicon from this pcr reaction, when digested with the restriction enzymes nla iv and sau 96i, gives a distinct banding pattern that can be used to. Pisum sativum mycosphaerella pinodes ascochyta pisi phoma medicaginis symptomatologie champi. Studies on the biology and control of ascochyta fabae on fa.
Several factors were investigated, including amount and concentration of inoculum, period of high humidity and age of leaves. Ascochyta blight is favored by cool, moist weather. Inoculation was made on mnpda medium for sporulation evaluation. Biological control strategies have not been developed for ascochyta blight of lentil. Ascochyta blight, an infection caused by a complex of ascochyta pinodes, ascochyta pinodella, ascochyta pisi, andor phoma koolunga, is a destructive disease in many field peas pisum sativum l. Aug 25, 2019 the major ones include ascochyta blight ascochyta fabae speg. As a result, seedlings emerging from infected seeds show severe disease development. Ascochyta blight of lentil grains, pulses and cereals. The fungus can survive on crop debris, selfsown volunteer plants, and infected seed. Older leaves proved to be less susceptible than younger leaves. Three fungi contribute to the ascochyta blight disease complex of pea pisum sativum. Based on comparisons of cultural and morphological traits among isolates of ascochyta fabae the causal agent of ascochyta blight of faba bean and isolates of a. Ascochyta blight ab caused by ascochyta rabiei pass.
Aug 08, 2019 the major ones include ascochyta blight ascochyta fabae speg. Practice a threeyear or longer crop rotation to nonhosts such as small grains or corn. In laboratory tests seed treatment with thiabendazole and benomyl resulted in a significant reduction in the number of seeds giving rise to colonies of a. Ascochyta blight of chickpeas plant management network. Planting clean, disease free seed is the safest method of control, although seed with up to 5% ascochyta lentis infection will not significantly affect yield as long as soil and weather conditions favor quick germination and good plant vigor. Effect of weather conditions on yield and health status of. Ascochyta blights occur throughout the world and can be of significant economic importance. The disease is particularly severe under cool and humid weather conditions. Ascochyta blight of chickpeas is caused by the fungal pathogen phoma rabiei formerly known as ascochyta rabiei which is specific to chickpeas. Furthermore ascochyta leaf blight development is sporadic and rapid. Ascochyta blight is the most severe disease of coolseason pulses davidson and kimber, 2007. Ascochyta fabae is a seedborne pathogen of all types of vicia faba, including broad beans.
Even if disease free seed is used and rotations are long, scout your chickpeas carefully for disease. Under the condition when disease free seed is not available, foliar spray is preferable to prevent spread of the disease. The line 29h is one of the most resistant accessions to the pathogen ascochyta fabae speg. The species didymella fabae anamorph ascochyta fabae that attacks vicia faba can survive and reproduce. The conidial stage is and is especially prevalent in spring on crops grown through the winter in mild climates such as western washington bailey et al. The minor, usually nonyield limiting diseases alternaria and cercospora can both be confused with ascochyta blight. Ascochyta blight of pea bugwood center for invasive. Pdf pseudothecia of didymella fabae, the teleomorph of ascochyta fabae, were first observed on. Variation in the production of ascochitine by ascochyta fabae.
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