Evaluation of Cassava Genotypes for Resistance to Cassava Mosaic Disease and Agronomic Traits

Patrick Chiza Chikoti,Paul Shanahan,Rob Melis

doi:10.4236/ajps.2016.77107

Abstract

Sixteen cassava genotypes comprising introductions, local landraces and improved genotypes were evaluated for two seasons in Mansa, Zambia, for their reaction to cassava mosaic disease (CMD). The study was conducted in 2009/10 and 2010/11 seasons to evaluate the reaction of cassava cultivars to CMD and agronomic traits. Cassava mosaic disease severity and leaf retention were scored at 6 months after planting (MAP) and data on yield and yield components were recorded at harvest (7 MAP). Significant genotype x season interaction for CMD, harvest index, fresh root yield, biomass, plant height, root size and leaf retention was recorded. Bangweulu, Kalaba, Chikula, Mwakamoya and Chila-7 were the most susceptible genotypes over the two seasons. Mweru, Kampolombo, TMS190, TMS3001, Tanganyika and Nalumino had low severity scores. Harvest index ranged from 0.36 (Mwakamoya) to 0.55 (Chila-7) for the combined seasons. Chila-7 had the highest fresh root yield with a mean of 0.87 kg plant-1 for the combined seasons. The resistant genotypes might be used to improve the CMD resistance of local cultivars through hybridisation.

Highlights

Cassava forms an integral part of the farming system in Zambia
Root size varied from 3 to 5 while fresh root yield ranged from 0.02 kg plant−1 to 2 kg plant−1
The development of cassava mosaic disease (CMD) was variable in the two seasons, which resulted in different levels of severity scores

Summary

Introduction

Cassava forms an integral part of the farming system in Zambia. A number of cassava landraces are grown byHow to cite this paper: Chikoti, P.C., Shanahan, P. and Melis, R. (2016) Evaluation of Cassava Genotypes for Resistance to Cassava Mosaic Disease and Agronomic Traits. Cassava forms an integral part of the farming system in Zambia. A number of cassava landraces are grown by. (2016) Evaluation of Cassava Genotypes for Resistance to Cassava Mosaic Disease and Agronomic Traits. In most of the communities, the crop is grown for its storage root. The cassava roots have variable uses such as fresh food, animal feed [1], starch extraction and alcohol production [2]. One of the important breeding objectives in many research institutions, for example the International Institute for Tropical Agriculture (IITA) and Centro Internationcional de Agricultura Tropical (CIAT), is producing cultivars which are high yielding, early bulking, resistant to pests and diseases, and with low cyanide glycoside content (HCN). Many of the cultivars grown in Zambia are susceptible to pests and diseases

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Conclusion