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. 2018:10:351-368.
doi: 10.1007/s12571-018-0779-2. Epub 2018 Mar 17.

Exchanging and managing in- vitro elite germplasm to combat Cassava Brown Streak Disease (CBSD) and Cassava Mosaic Disease (CMD) in Eastern and Southern Africa

Silver Tumwegamire  1 , Edward Kanju  1 , James Legg  1 , Rudolph Shirima  1 , Salehe Kombo  1 , Geoffrey Mkamilo  2 , Kiddo Mtunda  2 , Karoline Sichalwe  2 , Heneriko Kulembeka  2 , Innocent Ndyetabura  2 , Haji Saleh  3 , Robert Kawuki  4 , Titus Alicai  4 , Gerald Adiga  4 , Ibrahim Benesi  5 , Albert Mhone  5 , Anabela Zacarias  6 , Sofrimento Fenias Matsimbe  6 , Theresia Munga  7 , Elijah Ateka  8 , Lynet Navangi  7 , Midatharahally Narasegowda Maruthi  9 , Francis Mwatuni  10 , George Ngundo  10 , Maureen Mwangangi  10 , Edward Mbugua  11 , Joseph Ndunguru  12 , Cyprian Rajabu  12 , Deogratius Mark  12
Affiliations

Exchanging and managing in- vitro elite germplasm to combat Cassava Brown Streak Disease (CBSD) and Cassava Mosaic Disease (CMD) in Eastern and Southern Africa

Silver Tumwegamire et al. Food Secur. 2018.

Abstract

Cassava varieties resistant to cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) are needed for the food and income security of the rural poor in eastern and southern Africa (ESA). The International Institute of Tropical Agriculture led five national cassava breeding programs (Malawi, Mozambique, Kenya, Tanzania and Uganda) in virus-cleaning and exchanging elite cassava germplasm resistant to both diseases. This paper documents the experiences and lessons learned from the process. Thirty-one clones (25 elite, two standard and four national) were submitted by the five breeding programs to the Natural Resources Institute and Kenya Plant Health Inspectorate Services for virus cleaning and indexing. Subsequently, ca 75 invitro virus-indexed plantlets per clone were sent to Genetic Technologies International Limited (GTIL), a private tissue culture (TC) lab in Kenya, and micro-propagated to produce ≥1500 plantlets. After fulfilling all the formal procedures of germplasm exchange between countries ≥300 plantlets per clone were sent to each partner country. National check clones susceptible to CMD/CBSD were sent only to their countries of origin. In each country, the in-vitro plantlets were acclimatized under screen house conditions and transferred to clean isolated sites for field multiplication. All the clones were cleaned of the viruses, except Tomo. The cleaning process was slow for F19-NL, NASE1, and Kibandameno and TC micro-propagation at GTIL was less efficient for Pwani, Tajirika, NASE1, and Okhumelela than for the other clones. Difficulties in cleaning recalcitrant clones affected the timeline for establishing the multi-site evaluation trials in target countries. The initiative is the one of the kind to successfully clean and exchange elite germplasm as a joint action to combat CBSD in ESA. Adequate preparation in terms of infrastructure and personnel are critical to successfully receiving and adapting the indexed in-vitro plants as new germplasm.

Keywords: CBSD and CMD; Exchange; Germplasm; In-vitro.

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Conflict of interest statement

The authors declare that they have no conflict of interest pertaining with this work.

Figures

Fig. 1
Fig. 1
A map showing partner countries that exchanged elite cassava germplasm and sites for regional trials
Fig. 2
Fig. 2
Schematic flow of the cleaning, multiplication and exchange process of the cassava elite germplasm
Fig. 3
Fig. 3
Timelines for the process of cleaning, multiplication and exchange of the cassava elite germplasm
Photo 1
Photo 1
a micro-propagation at Genetic Technologies International Limited; b acclimitization work at Kibaha; c field multiplication of elite germplasmat Kandiyani,Malawi; and d partners of breeders and virologists in a cassava field in Malawi
Fig. 4
Fig. 4
Variation in in-vitro micro-propagation rates of different cassava clones at GTIL tissue culture lab, Nairobi. Sub-culturing was done after every 3 weeks of growth in-vitro
See this image and copyright information in PMC

References

    1. Acedo Z. V., & Corazon U. L. (2008). Rapid propagation of released Philippine cassava varieties through tissue culture. Journal of Root Crops, 34(2), 108–114.
    1. Adams I. P., Abidrabo P., Miano D. W., Alicai T., Kinyua Z. M., Clarke J., et al. (2013). High throughput real-time RT-PCR assays for specific detection of cassava brown streak disease causal viruses and their application to testing planting material. Plant Pathology, 62, 233–242.
    1. Alicai T., Omongo C.A., Maruthi M. N., et al. (2007). Re-emergence of cassava brown streak virus disease in Uganda. Plant Disease, 91(1), 24–29. - PubMed
    1. Aloyce R. C., Tairo F., Sseruwagi P., Rey M. E. C., & Ndunguru J. (2013). A single-tube duplex and multiplex PCR for simultaneous detection of four cassava mosaic begomovirus species in cassava plants. Journal of Virological Methods, 189, 148–156. - PubMed
    1. FAO (2010). Quality declared planting materials. Protocols and standards for vegetatively propagated crops. ISBN.978-92-5-106425-2 Pp126.

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