Articles
PROFILING CSSV-RESISTANCE OF SOME COCOA CULTIVARS IN GHANA
Article number
1007_80
Pages
691 – 698
Language
English
Abstract
Breeding for CSSV resistance is considered the most effective way of controlling cocoa swollen shoot virus disease (CSSVD) in the field.
However, breeding for CSSV resistance in Ghana has since its inception, had challenges such as the length of time it takes to screen each germplasm accession and the enormous volume of materials that have to be screened.
Measuring viral load for building CSSV-resistant profiles of cocoa cultivars gives an added opportunity to rapidly screen the cultivars for CSSV resistance.
The results showed that quantitative PCR (qPCR) can be used to accurately measure CSSV in cocoa cultivars inoculated with the virus just 5 days post inoculation (dpi), and the resulting data was used to determine the resistance or tolerance status of the cultivar as well as building their profiles.
Other results from the studies also confirmed the field experimental data that the Inter-Amazon and Amazon-Amelonado hybrids are more resistant than Amelonado (selfed). The hybrid T63/967 X T17/524 was also found to be highly resistant this result corroborates previous field data, which had consistently shown hybrids of T17 (particularly, T17/524) and T63 parentages to be highly resistant.
The statistical test aimed at determining whether Inter-Amazon hybrids, Amazon-Amelonado hybrids and Amelonado (selfed) can be categorised into highly resistant, moderately resistant and susceptible groupings, was inconclusive while the 5 dpi samples found the groupings to be significant (F pr=0.008), the 12 dpi samples showed otherwise (F pr=0.112). The importance of these findings on the screening of germplasm materials against CSSV and on the building of CSSV-resistant profiles of the cultivars is discussed.
However, breeding for CSSV resistance in Ghana has since its inception, had challenges such as the length of time it takes to screen each germplasm accession and the enormous volume of materials that have to be screened.
Measuring viral load for building CSSV-resistant profiles of cocoa cultivars gives an added opportunity to rapidly screen the cultivars for CSSV resistance.
The results showed that quantitative PCR (qPCR) can be used to accurately measure CSSV in cocoa cultivars inoculated with the virus just 5 days post inoculation (dpi), and the resulting data was used to determine the resistance or tolerance status of the cultivar as well as building their profiles.
Other results from the studies also confirmed the field experimental data that the Inter-Amazon and Amazon-Amelonado hybrids are more resistant than Amelonado (selfed). The hybrid T63/967 X T17/524 was also found to be highly resistant this result corroborates previous field data, which had consistently shown hybrids of T17 (particularly, T17/524) and T63 parentages to be highly resistant.
The statistical test aimed at determining whether Inter-Amazon hybrids, Amazon-Amelonado hybrids and Amelonado (selfed) can be categorised into highly resistant, moderately resistant and susceptible groupings, was inconclusive while the 5 dpi samples found the groupings to be significant (F pr=0.008), the 12 dpi samples showed otherwise (F pr=0.112). The importance of these findings on the screening of germplasm materials against CSSV and on the building of CSSV-resistant profiles of the cultivars is discussed.
Publication
Authors
H. Dzahini-Obiatey, R.T.V. Fox, B. Adomako, P.C. Aculey, G.A. Ameyaw, O. Domfeh
Keywords
CSSV, resistance, qPCR, breeding, screening, cocoa cultivars
Online Articles (119)