Person:
Kinyua, M.G.

Profile Picture
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
Kinyua
First Name
M.G.
Name
Kinyua, M.G.

Filters

2006 - 200932010 - 20141
Reset filters

Settings

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Antibiosis mechanism of resistance to Larger Grain Borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) in maize
    (Asian Network for Scientific Information, 2014) Nhamucho, E.; Mugo, S.N.; Kinyua, M.G.; Gohole, L.; Tadele Tefera; Mulima, E.P.
    Publication
  • Thumbnail Image
    Characterization of seedling infection types and adult plant infection responses of monogenic Sr gene lines to race TTKS of Puccinia graminis f. sp. tritici.
    (American Phytopathological Society (APS), 2007) Jin, Y.; Singh, R.P.; Ward, R.W.; Wanyera, R.; Kinyua, M.G.; Njau, P.N.; Fetch, T.; Pretorius, Z.; Yahyaoui, A.
    Stem rust, caused by Puccinia graminis f. sp. tritici, historically was one of the most destructive diseases of wheat and barley. The disease has been under effective control worldwide through the widespread use of host resistance. A number of stem rust resistance genes in wheat have been characterized for their reactions to specific races of P. graminis f. sp. tritici. Adult plant responses to race TTKS (also known as Ug99) of monogenic lines for Sr genes, a direct measurement of the effectiveness for a given gene, have not been investigated to any extent. This report summarizes adult plant infection responses and seedling infection types for monogenic lines of designated Sr genes challenged with race TTKS. High infection types at the seedling stage and susceptible infection responses in adult plants were observed on monogenic lines carrying Sr5, 6, 7a, 7b, 8a, 8b, 9a, 9b, 9d, 9g, 10, 11, 12, 15, 16, 17, 18, 19, 20, 23, 30, 31, 34, 38, and Wld-1. Monogenic lines of resistance genes Sr13, 22, 24, 25, 26, 27, 28, 32, 33, 35, 36, 37, 39, 40, 44, Tmp, and Tt-3 were effective against TTKS both at the seedling and adult plant stages. The low infection types to race TTKS observed for these resistance genes corresponded to the expected low infections of these genes to other incompatible races of P. graminis f. sp. tritici. The level of resistance conferred by these genes at the adult plant stage varied between highly resistant to moderately susceptible. The results from this study were inconclusive for determining the effectiveness of resistance genes Sr9e, 14, 21, and 29 against race TTKS. The understanding of the effectiveness of individual Sr genes against race TTKS will facilitate the utilization of these genes in breeding for stem rust resistance in wheat.
    Publication
  • Thumbnail Image
    Current status, likely migration and strategies to mitigate the threat to wheat production from race Ug99 (TTKS) of stem rust pathogen
    (CABI Publishing, 2006) Singh, R.P.; Hodson, D.P.; Jin, Y.; Huerta-Espino, J.; Kinyua, M.G.; Wanyera, R.; Njau, P.N.; Ward, R.W.
    Stem or black rust, caused by Puccinia graminis tritici, has historically caused severe losses to wheat (Triticum aestivum) production worldwide. Successful control of the disease for over three decades through the use of genetic resistance has resulted in a sharp decline in research activity in recent years. Detection and spread in East Africa of race TTKS, commonly known as Ug99, is of high significance as most wheat cultivars currently grown in its likely migration path, i.e. to North Africa through Arabian Peninsula and then to Middle East and Asia, are highly susceptible to this race and the environment is conducive to disease epidemics. Identifying/developing adapted resistant cultivars in a relatively short time and replacing the susceptible cultivars before rust migrates out of East Africa is the strategy to mitigate potential losses. Although several alien genes will provide resistance to this race, the long-term strategy should focus on rebuilding the ‘Sr2-complex’ (combination of slow rusting gene Sr2 with other unknown additive genes of similar nature) to achieve long-term durability. A Global Rust Initiative has been launched to monitor the further migration of this race, facilitate field testing in Kenya or Ethiopia of wheat cultivars and germplasm developed by wheat breeding programmes worldwide, understand the genetic basis of resistanceespecially the durable type, carry out targeted breeding to incorporate diverse resistance genes into key cultivars and germplasm, and enhance the capacity of national programmes. A few wheat genotypes that combine stem rust resistance with high yield potential and other necessary traits have been identified but need rigorous field testing to determine their adaptation in target areas.
    Publication
  • Thumbnail Image
    The spread of stem rust caused by Puccinia graminis f. sp. tritici, with Virulence on Sr31 in wheat in Eastern Africa
    (American Phytopathological Society (APS), 2006) Wanyera, R.; Kinyua, M.G.; Jin, Y.; Singh, R.P.
    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 with virulence to Sr31 were detected in Uganda in 1999 (1). During 2003 and 2004, a majority of
    Publication