ISSN 2167-0447
International Journal of Agricultural Sciences ISSN 2167-0447 Vol. 10 (6), pp. 001-010, June, 2020. © International Scholars Journals
Full Length Research Paper
A screening technique for resistance to FUSARIUM root rot of common bean
Clare M. Mukankusi1,2*, Rob J. Melis1, John Derera1, Robin A. Buruchara2 and D. Mark1
1African Centre for Crop Improvement, School of Agricultural Sciences and Agribusiness, University of KwaZulu-Natal, P. Bag X01, Scottsville 3209, Pietermaritzburg, South Africa.
2International Centre for Tropical Agriculture (CIAT), P. O. Box 6247, Kampala, Uganda.
Accepted 25 January, 2020
Abstract
Resistance to FUSARIUM root rot (FRR) in common bean is documented as a quantitative trait and as such is greatly influenced by several environmental factors. A reproducible disease screening technique that considers the selection environment is therefore important in selecting resistant lines. A study was conducted to evaluate soil composition and irrigation frequency on the severity of FRR, using a predominant pathogenic isolate from SW Uganda at the International Centre for Tropical Agriculture (CIAT) in Uganda. Five soil compositions (i) 80% lake sand:20% forest soil, ii) 50% lake sand:50% forest soil, iii) 80% swamp soil:20% forest soil, iv) 50% swamp soil:50% forest soil and v) forest soil alone), and five irrigation frequency levels (once a week, twice a week, three times a week, four times a week, and daily) were evaluated on six common bean varieties with varying levels of resistance to FRR. Forest soil and 50% swamp soil: 50% forest soil (soil composition); daily irrigation and irrigation once a week (irrigation frequency) differentiated test varieties most distinctly, according to their reaction to FRR. In conclusion, a combination of forest soil and daily watering using a pathogenic isolate FSP-3 provided adequate FRR disease levels for disease evaluation and differentiation of bean varieties and was adopted for genetic studies on FRR resistance in beans.
Key words: Common bean, Fusarium root rot, resistance, irrigation frequency, screening technique, soil composition.