A Review of the Breeding of Clonally Propagated Sweetpotato Genotypes for Acquired Resistance to Sweetpotato Pathogen Complex

Abstract:

The vegetative propagation of sweetpotato crop by farmers involves taking of vine cuttings, from a previous year's crop which increases the risk of a buildup of viruses and other pathogens. The importance of virus diseases and their buildup in farmers’ planting materials has been shown convincingly to drastically reduce yield of sweetpotato varieties. This has contributed to slow sweetpotato breeding process as a result of genotype decline, flower abortion and malformation of leaves. Chemical control measures to prevent virus insect vectors are no longer useful as chemical sprays destroy insects' pollinators. However, resistant sweetpotato varieties have made considerable contribution to plant breeding in terms of yield and provision of planting material. As a result of the merits of disease resistant sweetpotato varieties, this review discussed the ''Breeding of clonally propagated sweetpotato genotypes for acquired resistance to sweetpotato pathogen complex". The review indicated that sweetpotato plants that failed to inherit resistance genes could be made to acquire defense mechanisms in field evaluation in hotspot fields and agro-ecologies through adaptation breeding to incorporate resistance to pathogens in the clonally bred sweetpotato genotypes. This enable the sweetpotato genotypes acquires natural resistance to major diseases attacking the sweetpotato crop in the field. Resistance sweetpotato genotypes eliminates losses from diseases and are environmentally friendly.