A reference source for seed technologists part 1 diseases that are seedborne and seed transmitted fungi anthracnose black bundle black kernel rot black mold brown stripe downy mildew crazy top diplodia ear and stalk rot fusarium stalk and ear rot fusarium stalk and root rot horses tooth java downy mildew nigrospora ear rot. Downy mildew has been the most menacing disease of corn in tropical and sub tropical and subtropical regions of the world. It has multiple, fast life cycles in a growing season and can be very hard to control once it is established, so strategies are outlined below to avoid or treat early infection. The present study was aimed at detailed genetic analysis of resistance to two downy mildew pathogens of maize, sorghum downy mildew perenosclerospora sorghi. The main season of maize cultivation is rainy season and hence prone to many diseases and pests. Hence, we employed two molecular marker systems, namely ssr simple sequence repeat and ardra amplified ribosomal dna restriction analysis markers, to study the.
Optimal conditions for corn growth also are optimal for late wilt infection. A variety of dm strains have been reported, and the resistance to them is polygenically controlled. Multiple disease resistance in maize randall wisser 1, rebecca nelson 2, judith kolkman 2, ellie walsh 2, margaret smith 3, junyun yang 4 peter balintkurti1 1 usdaars, dept of plant pathology, north carolina state university, raleigh, nc 276957616, 2 dept. Sorghum downy mildew peronosclerospora sorghi, sdm is a damaging disease of sorghum and maize crops in africa. The distribution and spread of sorghum downy mildew in. Downy mildew disease, caused by peronosclerospora sorghi, is one of the most serious diseases of maize.
Effects of powdery mildew, triadimenol seed treatment, and. Infection of maize or other hosts is only considered where deemed necessary, particularly if information is lacking on a particular aspect for sorghum. Symptom and sign the young head, enclosed in the boot, is usually completely replaced by a large smut gall covered by a thick whitish membrane. Host plants beans, crucifers, cucurbits, maize, potato, tomato, rice, and a wide range of herbaceous and woody plants.
A new race race t of the southern corn leaf blight pathogen cochliobolus heterostrophus emerged in 1969 that was. Drought tolerant gm maize importation and field trials of drought tolerant gm maize into south africa monsanto have been granted permits permit no. The management of important disease and pests are briefly discussed below. Spore masses of maize downy mildew, peronosclerospora sacchari, on the white stripes centre. Use a correct and balanced fertilization program with proper levels of n, p and k. In the early 1990s, scientists in brazil became concerned about the growing spread of unidentified maize diseases in the crops major production areas. Disease and insect pest management in maize agropedia.
Sweet corn is the taste of summer, but if you grow it in your garden, you could lose your crop to pests or disease. Downy mildew on maize tends to cause yellow streaking down the fibrous leaves. Maize zea mays is the most widely produced grain in the united states. Nitrogen not only promotes tiller formation, causing dense stands, but also increases the susceptibility of the crop. Downy mildew dm is a major disease of maize that causes signi. International symposium on downy mildew of maize by hiroshi fuji department of plant pathology and entomology, national institute of agricultural science downy mildew is one of the most impor tant diseases of maize, sugarcane, and sor ghum in tropical and subtropical countries. Unesco eolss sample chapters soils, plant growth and crop production vol. Maize streak virus msv maize stripe maize chlorotic stripe, maize hoja blanca maize stripe virus. Executive summary philippine downy mildew of maize pdm, caused by the oomycete peronosclerospora philippinensis and brown stripe downy mildew bsdm caused by sclerophthora rayssiae var. A good alternative is to use a slowrelease fertilizer. Pdf unraveling the genetic diversity of maize downy. Wheat plots were established in central and eastern north carolina in the yields. Assessment of important plant disease of major crops.
Downy mildew dmresistant maize was selected from five cultivars using a spreader row technique. Infected seed, biological culture, or a small amount of infected crop. Assessment on major diseases of maize, sorghum, coffee haricot bean, mung bean and cow pea was undertaken at south omo zone south ari, and benatsemay woreda and segen peoples zone konsso woreda. Downy mildew dm is one of the most destructive diseases of maize in the humid subtropical and tropical regions of asia. Affected plants become stunted and exhibit bushy appearance due to shortening of internodes. These are two of several downy mildew diseases that occur in china, india, indonesia, nepal, pakistan. If you plant more susceptible varieties, you may need to take control measures. Forming linear or irregular whitish yellow to pale spots, often entirely discolouring the leaves and deforming the host. Epidemiology of downy mildew diseases of maize, sorghum.
Unraveling the genetic diversity of maize downy mildew in. Philippine downy mildew of maize perenosclerospora philippensis and. Nearly 32 million hectares of land were planted to maize in 2005 1. Shaw, an obligate pathogen that cannot be cultured in the laboratory. Bacterial leaf blight of rice kills seedlings and destroys the leaves of older plants. Epidemiology of downy mildew diseases of maize, sorghum and pearl millet based on a paper presented at the international conference on the graminaceous downy mildew diseases 28 november3 december 1979, bellagio, italy bonde, 1980b. Among the various maize diseases, downy mildews assume considerable importance in tropical and subtropical regions of the world. Choose hybrid varieties with known resistance to maize downy mildew. Ten downy mildew diseases are known on maize caused by two genera viz. Serious downy mildews of maize in asia include peronosclerospora sorghi sorghum downy mildew.
The disease is caused by an oomycete or water mould, not a fungus. Brown stripe downy mildew sclerophthora rayssiae var. Basal rot with lower internodes becoming soft and slimy. Maize rough dwarf nanismo ruvido maize rough dwarf virus mrdv maize sterile stunt maize sterile stunt virus strains of barley yellow striate virus maize streak.
It has determinate growth habit and the shoot terminates into the inflorescences bearing staminate or pistillate flowers generally protandrous, that is, the male flower matures earlier than the female flower. Powdery mildew is a fungal disease that affects a wide range of plants. In india, where the brown stripe downy mildew pathogen was first discovered, yield losses from brown stripe downy mildew range from 20 to 90% 3. Sphaerotheca fuliginea being the most commonly reported cause. Nafziger encyclopedia of life support systems eolss 1. Conferring resistance to downy mildew in maize zea mays l. Whether you grow ornamental plants or fruits and vegetables, there are forms of downy mildew which might develop in your garden. Downy mildew on sorghum and corn peronosclerospora spp. The major and economically important maize diseases reported are gray leaf spot, northern leaf blight, southern leaf blight, banded leaf and sheath blight, ear rot, stalk rot, head smut, common rust, downy mildew and brown spot. Amusa and others published control of downy mildew disease of maize in forest agroecologies of southern nigeria. Area under the powdery mildew curve was negatively correlated falls of 1985 and 1986 to determine yield. Powdery mildew is a fungal leaf disease that reduces yield and grain quality in susceptible wheat varieties. Maize and sorghum are the major cereal crops in south omo and segen peoples zone. Genetic analysis of resistance to sorghum downy mildew and.
White stripes of maize downy mildew, caused by peronosclerospora sacchari. Disease and insect pest management in maize maize is one of the most important grain crops in the world. Disease resistance in maize and the role of molecular. Maize tassel abortion maize tassel abortion virus mtav maize vein enation. Sweet corn downy mildew control managing downy mildew on. Effects of powdery mildew, triadimenol seed treatment, and triadimefon foliar sprays on yield of winter wheat in north carolina. Disease can be both stubble borne and carried over on green bridge, and management strategies include. Sclerophthora macrospora is the only downy mildew pathogen on maize under growing conditions in slovenia.
Bisi international, tbk, kedirieast java, indonesia. The temporal and spatial development of local lesions of sdm on sorghum in zimbabwe was investigated by assessing the local lesion. It depends on the type of downy mildew, and there are a lot. Stay informed about pannar products, services and other offerings. Varying effectiveness of metalaxyl fungicides and disease incidences caused by downy mildew to maize in several places in indonesia led to the speculation that genetic variation of peronosclerospora species in indonesia exists. The scientific and technical content of this document is current to the date published and all efforts. The pathogen bsdm is caused bysclerophthora rayssiaevar. November 2008 powdery mildew on vegetables melons, peas, pumpkins, and squash.
The most effective and efficient way of managing losses due to dm is to develop durable hostplant resistance in asian maize across different dm pathogens. Recovery plan for philippine downy mildew and brown stripe. Biological control of downy mildew of maize caused by. Disease resistance in maize and the role of molecular breeding in defending against global threat f farhan ali 1,2 and jianbing yan. Sorghum downy mildew of maize is a disease of great destructive potential because systemically infected plants seldom produce an ear. Out of these, sorghum downy mildew and brown stripe downy mildew are common in our country. Cultural practices plant in sunny areas as much as possible, provide good air circulation, and avoid applying excess fertilizer. In 1959 it has been found in nasice croatia for the first time. Introduction maize zea mays l is the most important and most widely distributed cereal in the world after wheat and rice. Downy mildew on corn, rice, wheat sclerophthora spp. Identification of downy mildew resistance gene candidates by.
Maize downy mildew 227 common name sugarcane downy mildew scientific name peronosclerospora sacchari distribution asia, africa nigeria only, oceania. Do not plant maize close to sugarcane in case of crosscontamination. The disease is extremely serious worldwide and has emerged as a major problem in irrigated crops in the sahel. Powdery mildew thrives where high rates of nitrogen have been used. Brown stripe downy mildew of corn plant management. Jayaraman department of genetics and plant breeding, agricultural engineering college and research institute, tamil nadu agricultural university, kumulur, trichy 621 712, india abstract in the present study diallel analysis was adopted and nine parents were crossed in all.
Thurston slide number 44 date site hosts disease name. Threat specific contingency plan plant health australia. This is a title only record which contains no abstract. Runs analysis was used to study the distribution of systemically infected sorghum and maize plants in nigeria and zimbabwe. Crop loss sorghum downy mildew is particularly destructive be.
Powdery mildew diseases are caused by many different species of fungi in the order erysiphales, with podosphaera xanthii a. Watch for mildew in fields receiving greater than 70 lb n per acre. Sorghum downy mildew sdm of maize is caused by the oomycete peronosclerospora sorghi weston and uppal c. Maize streak, maize stripe and maize mosaic virus diseases.
Yes, i wish to receive product andor promotional communications. If you want to stay informed by email, please let us know by checking the box below. Although this disease is quite common in south africa, plants showing these symptoms are normally fairly sparse. Managing powdery mildew in wheat agriculture and food. Sdm and rajasthan downy mildew perenosclerospora heteropogoni. Research efforts can be targeted to address both yield potential and onfarm yields by reducing the impacts of abiotic and biotic constraints. Chlorotic streaks appear on the leaf and white fungus growth is seen on both the surfaces of leaf. Pacific pests and pathogens fact sheet maize downy mildew 227 common name sugarcane downy mildew scientific name peronosclerospora sacchari distribution.
Therefore, in order to streamline the future direction of maize research in. Knowing how to prevent downy mildew in corn and how to control an infection if you see it in your garden is important. Maize streak, maize stripe and maize mosaic virus diseases qj in the tropics africa and islands h in the indian ocean impact of maize virus diseases and current research vectors and epidemiology maize virus diagnosis and maize streak virus variability maize resistance and breeding dossier prepared by f. Unraveling the genetic diversity of maize downy mildew in indonesia rudy lukman1, ahmad afifuddin1 and thomas lubberstedt2 1biotech department of pt. Downy mildew on sweet corn is one of these diseases, a fungal infection that can stunt plants and reduce or destroy the harvest. Maize is monoecious pistillate ear, the female flower and staminate tassel, the male flower. Downy mildew on grasses and millet sclerospora spp.
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