A5084634989- Wheat and Barley Genetics and Pathology
- Plant Disease Resistance and Genetics
- Genetics and Plant Breeding
- Yeasts and Rust Fungi Studies
- Genetic Mapping and Diversity in Plants and Animals
- Plant Pathogens and Resistance
- Bioenergy crop production and management
- Crop Yield and Soil Fertility
- Agriculture, Plant Science, Crop Management
- Power Systems and Technologies
- Agricultural Productivity and Crop Improvement
- Agricultural economics and policies
- Flowering Plant Growth and Cultivation
- Rice Cultivation and Yield Improvement
- Forest Ecology and Biodiversity Studies
- Plant Pathogenic Bacteria Studies
- Berry genetics and cultivation research
- Horticultural and Viticultural Research
- Plant pathogens and resistance mechanisms
Kenya Agricultural and Livestock Research Organization
2015-2022
International Maize and Wheat Improvement Center
2016-2017
Cereal Disease Laboratory
2016
Agricultural Research Service
2016
Edward T. Schafer Agricultural Research Center
2016
North Dakota State University
2016
University of Minnesota
2016
Aarhus University
2016
Agriculture and Agri-Food Canada
2016
Maricopa Medical Center
2016
Abstract Stem or black rust, caused by Puccinia graminis tritici , has historically severe losses to wheat ( Triticum aestivum ) production worldwide. Successful control of the disease for over three decades through use genetic resistance resulted in a sharp decline research activity recent years. Detection and spread East Africa race TTKS, commonly known as Ug99, is high significance most cultivars currently grown its likely migration path, i.e. North Arabian Peninsula then Middle Asia, are...
Stem rust, caused by Puccinia graminis f. sp. tritici, historically was one of the most destructive diseases wheat and barley. The disease has been under effective control worldwide through widespread use host resistance. A number stem rust resistance genes in have characterized for their reactions to specific races P. tritici. Adult plant responses race TTKS (also known as Ug99) monogenic lines Sr genes, a direct measurement effectiveness given gene, not investigated any extent. This report...
The stem rust resistance gene Sr36 confers a near-immune reaction to many races of Puccinia graminis f. sp. tritici and is highly effective against race TTKSK (syn. Ug99), which possesses unusually broad virulence combinations. Because this widely used in United States soft winter wheat germplasm cultivars, it has been considered be an important source TTKSK. In 2007, moderately susceptible infection responses were observed on lines cultivars carrying field screening nursery for at Njoro,...
Stem rust resistance in wheat cultivars with Sr31 has been effective and durable worldwide for more than 30 years. Isolates of Puccinia graminis f. sp. tritici virulence to were detected Uganda 1999 (1). During 2003 2004, a majority current Kenyan large portion CIMMYT germplasm gene planted Kenya susceptible stem rust. Six isolates collected during 2004 at different locations tested on the 16 North American race differentials following Sr genes: Sr5, 6, 7b, 8a, 9a, 9b, 9d, 9e, 9g, 10, 11,...
Wheat stripe rust (yellow [Yr]), caused by Puccinia striiformis f. sp. tritici, is an economically important disease of wheat worldwide. Virulence information on P. tritici populations to implement effective control with resistant cultivars. In total, 235 isolates from Algeria, Australia, Canada, Chile, China, Hungary, Kenya, Nepal, Pakistan, Russia, Spain, Turkey, and Uzbekistan were tested 20 single Yr-gene lines the genotypes that are used differentiate races in United States. The...
Wheat stem rust (Puccinia graminis f. sp. tritici) race TTKSK (Ug99), with virulence to the majority of world's wheat (Triticum aestivum) cultivars, has spread from Uganda throughout eastern Africa, Yemen, and Iran. The identification variants additional resistance genes reminded breeders pathologists danger deploying major alone. In order protect this rapidly spreading adapting pathogen, multiple are needed, preferably improved germplasm. Preliminary screening over 700 spring breeding lines...
Frequent emergence of new variants in the Puccinia graminis f. sp. tritici Ug99 race group Kenya has made pathogen survey a priority. We analyzed 140 isolates from 78 P. samples collected between 2008 and 2014 identified six races, including three not detected prior to 2013. Genotypic analysis 20 2013 collections showed that races TTHST, TTKTK, TTKTT belong group. International advanced breeding lines were evaluated against an isolate (Sr31, Sr24, SrTmp virulence) at seedling stage. From 169...
The recently identified Puccinia graminis f. sp. tritici (Pgt) race TTKSK (Ug99) poses a severe threat to global wheat production because of its broad virulence on several widely deployed resistance genes. Additional virulences have been detected in the Ug99 group races, and spread this has documented across growing regions Africa, Middle East (Yemen), West Asia (Iran). Other broadly virulent Pgt such as TRTTF TKTTF, present further difficulties maintaining abundant genetic for their...
Stem rust is one of the most devastating diseases wheat. Widely virulent races pathogen in Ug99 lineage (e.g., TTKSK) are threatening wheat production worldwide; therefore, there an urgent need to enhance diversity resistance genes crop. The objectives this study were identify new sources wheat-alien introgression derivatives from Secale cereale, Leymus mollis, L. racemosus, and Thinopyrum junceiforme, postulate conferring resistance, verify postulated by use molecular markers. From seedling...
Genetic resistance against biotic stress is a major goal in many wheat breeding programs. However, modern cultivars have limited genetic variation for disease and pest there always possibility of the evolution new diseases pests to overcome previously identified genes. A total 125 synthetic hexaploid wheats (SHWs; 2n = 6x 42, AABBDD, Triticum aestivum L.) were characterized fungal pathogens that cause rusts (leaf; Puccinia triticina, stem; P. graminis f.sp. tritici, stripe; striiformis...
Wheat landraces provide a source of genetic variability for breeding. The emergence and spread highly virulent races the stem rust pathogen (Ug99 race group Puccinia graminis f. sp. tritici) threaten wheat production globally. Spring were screened resistance in eight field seasons at Kenya Agricultural Research Institute, Njoro, where Ug99 has become endemic. Accessions showing one season retested with molecular markers associated genes Sr2, Sr24, Sr36, Lr34/Yr18; two height-reducing genes;...
Loci conferring resistance to the highly virulent African stem rust race TTKSK were identified in advanced barley breeding germplasm and positioned chromosomes 5H 7H using an association mapping approach. races of pathogen (Puccinia graminis f. sp. tritici) are a serious threat production worldwide because their wide virulence. To discover characterize US germplasm, over 3,000 lines/cultivars assessed for at seedling stage greenhouse also adult plant field Kenya. Only 12 (0.3 %) 64 (2.1...
The emergence of widely virulent pathotypes (e.g., TTKSK in the Ug99 race group) stem rust pathogen (Puccinia graminis f. sp. tritici) Africa threatens wheat production on a global scale. Although intensive research efforts have been advanced to address this threat wheat, few studies conducted barley, even though such as are known attack crop. main objectives study were assess vulnerability barley pathotype and identify possible sources resistance. From seedling evaluations more than 1,924...
The emergence of a new virulent race stem rust (Puccinia graminis f. sp. tritici) wheat (Triticum aestivum), TTKS (Ug99), calls for urgent measures to contain the disease, which is serious threat production in Kenya. Nine commercial fungicides were evaluated control field three locations 2005 and 2006. Ten treatments, including untreated control, applied on plots randomized complete block design with four replications. Assessment severity was done at growth stage (GS) 55 (heading), GS 65...
Abstract Background Transcriptomics is being increasingly applied to generate new insight into the interactions between plants and their pathogens. For wheat yellow (stripe) rust pathogen ( Puccinia striiformis f. sp. tritici , Pst ) RNA-based sequencing (RNA-Seq) has proved particularly valuable, overcoming barriers associated with its obligate biotrophic nature. This includes application of RNA-Seq approaches study gene expression dynamics over time population composition through use a...
Wheat stem rust has reemerged as a serious disease caused by new variants of Puccinia graminis f. sp. tritici. Variants with significant virulence and broad geographic distribution (Africa, Central Asia, Europe) include the Ug99 race group, TTRTF, TKTTF group. Genetic analysis placed isolates representing these critical virulent races into 12 genetic groups that make up clades I to IV. Development molecular diagnostic assays for will be an important component global surveillance efforts. A...