Investigation on Cacao swollen shoot virus (CSSV) pollen transmission through cross-pollination

Ameyaw, G. A.; Wetten, A.; Dzahini-Obiatey, H.; Domfeh, O.; Allainguillaume, Joel

Abstract

DNA- and RNA-based polymerase chain reaction (PCR) systems were used with Cacao swollen shoot virus (CSSV) primers designed from conserved regions of the six published genomic sequences of CSSV to investigate whether the virus is transmissible from infected trees through cross-pollination to seeds and seedlings. Pollen was harvested from CSSV infected cocoa trees and used to cross-pollinate flowers of healthy cocoa trees (recipient parents) to generate enough cocoa seeds for the PCR screening. Adequate precautions were taken to avoid cross-contamination during duplicated DNA extractions and only PCR results accompanied by effective positive and negative controls were scored. Results from the PCR analyses showed that samples of cocoa pod husk, mesocarp and seed tissues (testa, cotyledon and embryo) from the cross-pollinations were PCR negative for CSSV DNA. Sequential DNA samples from new leaves of seedlings resulting from the cross-pollinated trees were consistently PCR negative for presence of portions of CSSV DNA for over 36months after germination. A reverse transcription-PCR analysis performed on the seedlings showed negative results, indicating absence of functional CSSV RNA transcripts in the seedlings. None of the seedlings exhibited symptoms characteristic of the CSSV disease, and all infectivity tests on the seedlings were also negative. Following these results, the study concluded that although CSSV DNA was detected in pollen from CSSV infected trees, there was no evidence of pollen transmission of the virus through cross-pollination from infected cocoa parents to healthy cocoa trees. © 2012 The Authors. Plant Pathology © 2012 BSPP.

• Journal Article Type: Article
• Publication Date: Apr 1, 2013
• Deposit Date: Oct 3, 2012
• Publicly Available Date: Feb 10, 2016
• Journal: Plant Pathology
• Print ISSN: 0032-0862
• Electronic ISSN: 1365-3059
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 62
• Issue: 2
• Pages: 421-427
• DOI: https://doi.org/10.1111/j.1365-3059.2012.02640.x
• Keywords: badnavirus, CSSV, PCR, pollen, seed transmission, Theobroma cacao
• Public URL: https://uwe-repository.worktribe.com/output/951298
• Publisher URL: http://dx.doi.org/10.1111/j.1365-3059.2012.02640.x
• Additional Information: Additional Information : Article first published online: 28th May, 2012
• Contract Date: Feb 10, 2016