Dr Richard Ombui Nyankanga is a senior lecturer in the department of plant science and crop.
He is a horticulturalist by training with Bsc in Horticulture from Egerton University Msc and
PhD in horticulture from Cornell University U.S.A .He is currently serving as a manager field
He teaches course in general agriculture, horticulture, physiology, for both undergraduate and
postgraduate students. He is also actively involved in the supervision of Msc. and PhD student.
His research interests are in Horticultural production and protection, farmer’s knowledge and

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Nyankanga, RO, Wein HC, Olanya OM.  2008.  Relationship Between Incidence of Late Blight Tuber Rot, Foliage Blight Control and the Effect of Weather and Soil Variables. Abstract

The relationship of late blight disease, tuber blight and the effects of weather and soil variables were determined at 2 distinct environments of New York and Kenya during 1999 to 2001. In well replicated field experiments at the two sites where A2 (US8 clone) and A1 (US1 clone) respectively are dominant, foliar and tuber blight development, climatic and soil variables were quantified during three cropping seasons. Variation in tuber blight in New York and Kenya was detected. Stepwise multiple regression and correlation analysis identified combinations of variables associated with tuber blight such as cultivar characteristics, soil temperature and precipitation events. The research results can provide insight into the dynamics of tuber blight infection processes and be useful for tuber blight management strategies.

Nyankanga, RO.  2008.  Effects of Mulch and Potato Hilling. (51):101-111.abstract_3.pdf
Nyankanga, RO.  2008.  Development of Tuber Blight. (5)(43):1501-1508.abstract_2.pdf


Kikuvi, GM, Schwarz S, Mitema ES, Kehrenberg C.  2007.  Streptomycin and chloramphenicol resistance genes in Escherichia coli isolates from cattle, pigs, and chicken in Kenya. AbstractWebsite

The aims of this study were to determine the genetic basis of streptomycin and chloramphenicol resistance in 30 Escherichia coli isolates from food animals in Kenya and the role of plasmids in the spread of the resistance. Seven of the 29 streptomycin-resistant isolates harbored both the strA and strB genes. Twenty-one of isolates had the strA, strB, and aadA1 genes. The strA gene was disrupted by a functional trimethoprim gene, dfrA14 in 10 of the 21 isolates harboring the three streptomycin resistance genes. Physical linkage of intact strA and sul2 genes was found in two different plasmids from four isolates. Linkage of cassette-borne aadA1 and dfrA1 genes in class 1 integrons was found in two of the isolates. Chloramphenicol resistance was due to the gene catA1 in all the chloramphenicol resistant isolates. The strB, strA, and catA1 genes were transferable by conjugation and this points to the significance of conjugative resistance plasmids in the spread and persistence of streptomycin and chloramphenicol resistance in food animals in Kenya.


Nyankanga., RO.  2006.  Dynamics of development of late blight. Dynamics of development of late blight. 28:84-94.abstract_1.pdf


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