Pdf status and strategies in breeding for rust resistance in wheat. If stem rust overcomes an important resistance gene, all varieties protected by that gene will. The past, present and future of breeding rust resistant wheat. Determine if an herbicide resistant variety is necessary. To develop diseasefree germplasm, wheat material was screened using the. Depending on variety, location and yield potential, control should include a mixture of. Likewise they may be resistant in the same region in one year and susceptible in another. In the first place it was observed that resistance to rust was possessed. Nov 10, 2020 a stateoftheart study of plant dna provides strong evidence that farmers in ethiopia have widely adopted new, improved rust resistant bread wheat varieties since 2014. Haplotype analysis of molecular markers linked to stem rust. Among 42 egyptian wheat varieties screened for leaf rust resistance, only 9 varieties.
The varieties developed by breeders have a high productive potential, which cannot fully be realized because of crop diseases 2. Although the belief that good varieties sell themselves may be true, variety turnover. These resistant varieties can also be used by wheat breeders to develop new varieties. Frontiers the past, present and future of breeding rust resistant wheat. Mar 18, 2020 when leaf spot and stripe rust disease levels were high, a foliar fungicide application was necessary to reduce yield losses even on resistant varieties.
Most rl wheat varieties are susceptible to yellow rust at the seedling stage up to stem elongation but resistant at the adult stage. Resistant to stripe rust but susceptible to leaf rust. Until the exact reactions to the new races of stem rust can be determined, it may be useful to group varieties based on the stem rust resistance genes they contain. Test entries were planted in a single row of 2 meter including millat2011. While significant research on the adoption and impacts of improved crop varieties exists, most studies have analyzed yield effects in general without distinguishing between different varietal traits and characteristics. Pdf molecular markers for the identification of resistance. Stem rust of wheat with diagram biology discussion. Plant%20disease20reports 2009kswheatdiseaselossesimates. Some rust resistant varieties of wheat are available in india. Screening of wheat genotypes for leaf rust resistance along with.
Identification of stem rust resistance genes in the winter wheat. More information regarding disease resistant varieties can be found in the kstate research and extension publication wheat variety disease and insect ratings, mf991. Resistance to rusts in bangladeshi wheat triticum aestivum l. Identification of stem rust resistance genes in wheat. Nov 20, 2017 breeding crops for disease resistance is a sustainable approach to reduce yield losses.
Production function estimates suggest that improved resistant varieties raise effective yields by 8% in comparison to local susceptible varieties. The newly bred hybrids np 822, np 823 and np 825 have given good results. In this study, 117 pakistani wheat varieties were screened with 18 dna markers to detect the presence of stem rust resistance genes sr2, sr6, sr22, sr24, sr25, sr26, sr31, and sr38. The genes conferring rust resist ance in the breeding lines and wheat varieties released in bangladesh were investigated at cimmytmexico and. Rust diseases of wheat fsa7547 bumpers college university. Wheat breeding for disease resistance by interspecific and. It is resistant to leaf rust, powdery mildew and moderately resistant to barley yellow dwarf. The ahdb recommended list rl wheat yellow rust ratings reflect the resistance of adult plants during the main part of the growing season from about stem extension onwards. Areas with a high incidence of stem rust resistance were found in ethiopia, chile, turkey, bosnia and herzegovina, and adjacent areas of the former yugoslavia. Because the resistance of chinese wheat varieties to the new races ug99, tkttf, and ttttf is very poor, if these races spread into china they will cause massive losses in wheat production cao et al. Currently about ug99 lineage are recorded in thirteen countries. Np 710, np 718 and np 770 find favour with the farmers.
Growing resistant varieties keeps the level of stripe rust low, so that other controls are not required. Wheat along with rice and maize is fulfilling half of the calories demands of the world. Ug99 that was able to infect wheat triticum aestivum l. Plan to apply inexpensive fungicide with winter wheat herbicide if there is stripe rust in the region. Nov 24, 2014 before looking into that, some sr2 history.
Leaf, stem, and stripe rust diseases of wheat nmsu aces new. Genetic analysis of rust resistance genes in global wheat. Wheat and barley response to stripe rust and fungicides. Yield effects of rustresistant wheat varieties in ethiopia springerlink. Building a resilient wheat seed system to resist rust. It is resistant to the wheat soilborne mosaic and wheat spindle streak mosaic complex, and to stripe rust. Yield effects of rustresistant wheat varieties in ethiopia. Partial resistance traits of wheat seedlings were present in 12 varieties sids12. Know the level and type of resistance of the varieties. Sr24 and sr36 were originally transferred from alien species to bread wheat smith et al.
In r varieties, there is no evidence of sporulation on leaves and flag leaves have retained 95 to 100% of their photosynthetic leaf area. Although the belief that good varieties sell themselves may be true, variety. Today, no blockbuster variety rules the wheat seed market as public and private research institutions continuously bring improved varieties. Wheat stripe rust alert department of primary industries. Nsw dpi and the university of sydney have collaborated on stripe rust diagnostics and research since 1980 and latest cereal rust report pdf, 393 kb is. Rust diseases of wheat in north dakota publications. Haplotype diversity of stem rust resistance loci in. Pdf seedling and adult plant resistance to stripe rust in. Growing more and more resistant varieties will reduce chemical application and prevent stripe rust damage. Leaf rust resistance genes were initially introduced into common wheat cultivars. Global wheat production has increased tremendously since green revolution in 1960s and helped in minimizing hunger and malnutrition. Breeding rust resistant varieties of wheat canadian. Varieties in the mr class are moderately resistant, however some degree of.
Because stripe rust has been the most significant rust disease since 2000, it is very important to choose a variety with resistance to stripe. Developing countries, which consume 60% of the global wheat production, have shown a higher yield increase than the developed countries in the past 1. Table 2 lists the relative rust resistance of the wheat varieties recommended for georgia in 201415. Plant breeders have been able to develop genetic resistance or tolerance within wheat cultivars to a variety of races of the rusts. Resistant varieties significantly reduce both infection and spore production, which reduces spread. Genes for wheat stem rust resistance postulated in. Resistant levels are updated each year for varieties. Initially, wheat lines with sr24 and sr36 were resistant to ug99. Building a resilient wheat seed system to resist rust risks. Hope was selected for quality and high level stem rust resistance under field conditions. Mf991 wheat variety disease and insect ratings 2020.
Yield effects of rust resistant wheat varieties in ethiopia. Nov 11, 2020 wheat fields in the arsi highlands, ethiopia, 2015. Stem rust susceptibility of european wheats under australian conditions posed a significant threat to wheat production for the early british settlers in australia. Ug99 is a race of stem rust that is virulent to the majority of wheat varieties. The cultivation of varieties immune to the rust disease is an important means of combating the disease. Raghu and others published seedling and adult plant resistance to stripe rust in uttarakhand landraces of wheat find, read and cite all the research you need on.
May 30, 2018 samples of stripe rust found on any wheat variety should be sent in paper packaging, not plastic, to the australian rust survey, university of sydney, reply paid 88076, narellan, nsw 2567. Wheat germplasm screening for stem rust resistance using. Detection of genomic regions associated with resistance to. Using resistant varieties minimises the amount of rust in a district and reduces the chance of new pathotypes occurring. These diseases should be top priorities when selecting wheat varieties for that region. Status and strategies in breeding for rust resistance in wheat. Mar 18, 2020 the most effective, economical, and environmentally safe protection against rusts is the use of resistant wheat varieties. Status and challenges of wheat stem rust puccinia graminis f. See figure 3 for an example of wheat germplasm screening in georgia. Mcintosh and gyarfas 1971 and were widely used by wheat breeders. By establishing the borlaug global rust initiative bgri in 2005 to support wheat research and meet the threats headon, the nobel laureate was instrumental in launching the durable rust resistance in wheat drrw project 20082016, followed by the delivering genetic gain in wheat.
Wheat stem rust had largely been under control for about 30 yr the second half of the 20th century due to the widespread use of resistant varieties, such as those featuring the major. However, many current varieties are susceptible, and other controls are needed. Here, panel data from wheat farmers in ethiopia were used to compare improved varieties. In eastern and central kansas, the environment is often more conducive for disease development, and additional factors should be. Leaf rust occurs more regularly and in more worldwide regions than stem rust or stripe rust of wheat.
Resistant varieties significantly reduce both infection and spore production, which reduces spread to surrounding fields. Seven spring wheat and 3 barley varieties cultivars with varying levels of stripe rust resistance were compared for disease reaction, and yield and quality losses at lacombe and olds, alberta. Identification of seedling resistance to stem rust in. Mf2989 identification and management of stem rust on. Consult a current wheat variety guide when selecting cultivars for stem rust management to check the susceptibility rating. Identification and control of leaf rust of wheat in georgia. New study identifies wheat varieties that resist the. The famous australian wheat breeder, william farrer, tackled the problem of stem rust susceptibility through breeding fastmaturing wheat cultivars. Research genetic variation for markers linked to stem rust. Stem rust resistance genes sr22, sr24, sr25, and sr26 were absent.
Molecular markers for the identification of resistance genes and markerassisted selection in breeding wheat for leaf rust resistance. Genetic analysis of leaf rust resistance genes originating from wild species some wild cultivars of wheat or wild grasses, such as aegilops tauschii coss. Varietal change and adoption of rust resistant wheat varieties in ethiopia from 200910 to 2014. The amount of rust on them depends on the presence or absence of forms which can attack them. Today, no blockbuster variety rules the wheat seed market as public and private research institutions continuously bring improved varieties into the system. Consult the ndsu extension publications a574, north dakota hard red spring wheat variety trial results and selection guide, and a1196, north dakota hard red winter wheat variety trial results and selection guide, for current rust resistance ratings of public and private varieties. Planting resistant varieties is the best way to control wheat rusts. Two classes of genes are used for breeding rust resistant wheat.
Wheat stem rust was not problem for the last three decades, but after the emergence of ug99 in uganda, the new race of stem rust ug99 was subsequently shown to attack the stem rust resistance genes sr31 and sr38, which were previously effective resistance genes. We should therefore make full use of wheat cultivar. To develop disease free germplasm, wheat material was screened using the. Because new races of the fungus can develop, it is important to know the susceptibility of a given wheat variety.
Pdf seedling and adult plant resistance to stripe rust. An important step towards reducing the vulnerability of wheat in africa and asia to the ug99 race of the stem rust pathogen is the substitution of current susceptible varieties with superior resistant varieties. Wheat growers should choose the resistant varieties identified in this study. Classification of varieties as r, mr, ms and s have implications for management and potential yield loss due to stripe rust. Therefore, wheat breeders and pathologists emphasizes on the development of high yielding and stripe rust resistant wheat varieties in order to combat. Resistant varieties retain a large amount of leaf area while more susceptible varieties show a larger percentage of leaf area covered by stripe rust. It is important that growers are aware of a variety s resistance reaction to stem rust. Using varieties that are resistant to leaf rust and adapted to your area is recommended. Among the three rust resistant varieties, kakaba appears to be the most important, grown by 49% of households, followed by digelu and dandaa, grown by 14% and 5% of the sample households, respectively in terms of area, about 67% of the wheat area is under rust resistant varieties. Sustainable rust resistance has been achieved in a number.
Geographic distribution of stem rust resistance in wheat. Sep 17, 2020 growing more and more resistant varieties will reduce chemical application and prevent stripe rust damage. This new population of stripe rust can overcome the resistance of many popular varieties including fuller, santa fe, overley, jagger, and jagalene. Southeastern australia suffered a severe stem rust epidemic in 1973, which gave. Durable rust resistance in wheat phase ii stem rust races in the targeted countries threatened by ug99. The results obtained from 4,000 plots, published in nature scientific reports, found that nearly half 47% of the area sampled was grown to varieties 10 years old or younger. Proportion of wheat area sown to rust resistant varieties by aez and year. Beside this, the variety millat2011 was also tested in local disease screening nurseries and national disease screening nurseries during the study period for consecutive years. Borlaug global rust initiative, south asia, 20082020.
It is resistant to the wheat soilborne mosaic and wheat spindle streak mosaic complex, and to stripe rust in the adultplant stages. Ug99 is a lineage of wheat stem rust puccinia graminis f. Though development of rust resistant wheat varieties has been given due attention, until recent years, building resilient wheat seed supply systems to rust risks remained unexplored and unpracticed. Phenotypic and molecular characterization of wheat leaf rust resistance gene.
Varieties in the r class are highly resistant to stripe rust table 1. Rustresistant bread wheat varieties widely adopted in. Phenotypic and molecular characterization of wheat leaf rust. Sustainable wheat rust resistance food and agriculture. Resistance to multiple races at the seedling stage was most frequent in accessions from ethiopia and turkey. The fungus can rapidly overcome resistance in current wheat varieties, and new sources must be used. Mf2989 identification and management of stem rust on wheat. Resistance in durum wheat was more frequent than resistance in common. The 1bl1rs translocation from cereal rye was used widely in wheat breeding, and for some time provided resistance to the wheat leaf rust, stripe rust, and stem rust pathogens conferred by genes. More than 70 leaf rust resistance genes have been iden tified, most of which are involved in racespecific cate gory and follow the boom and bust cycle due to the high pathogenic variability of. Producers must use the most recent information on wheat. The projects goals, however, will be realized only when farmers are planting seed of durably resistant and agronomicly improved varieties.
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