Tackling black leaf streak disease and soil fertility constraints to enable the expansion of plantain production to grassland in the humid tropics

Abstract

In Central Africa, plantain is traditionally grown after a forest fallow. Given increasing urban demand and a lack of forest fallows near urban centres, as well as poor roads and environmental concerns to reduce pressure on forests, research is needed to identify suitable shade, fertility management and cultivars to shift production of plantain to grasslands and to reduce losses to diseases such as black leaf streak disease (BLSD). Effects of light level (full, 67%, 33% light), and nitrogen (N)-amendment on BLSD-tolerant (FHIA-21) and BLSD-susceptible (Batard) cultivars planted on soil from paired grassland and forest sites were determined. BLSD and growth were monitored until 5 months after planting. Three months after planting, leaf area attacked on cultivar FHIA-21 was less than half that on Batard. Plants grown under 33% and 67% light had less leaf area attacked (2.9% and 4.6%, respectively) than those grown in full light (7.3%). Leaf area and dry matter (DM) were higher under shade and when grown on forest soils. Compared to growing BLSD-susceptible plantain on forested land under shade, a shift onto grasslands and a reduction in shade use is predicted to reduce yields. Using cultivar FHIA-21 may limit, but not eliminate, yield loss.

Keywords:

• Black leaf streak disease
• black sigatoka
• FHIA-21
• Musa spp. AAB
• Mycosphaerella fijiensis
• plantain
• shade

Acknowledgements

Thank you to the farmers and chiefs who permitted us to excavate the soil. Thanks to D. Essimi, J. Essah, S. Ndameda, E. Nanga, and X. Nkada for assistance, R. Ndango (IITA) for soil analyses and S. Hauser (IITA) for rainfall data. Special thanks to C. Owono Owono, who helped with growth assessments and to staff of IITA Mbalmayo. Fieldwork was funded by the Robert Bosch Stiftung, Stuttgart, Germany through grant 32.5.8041.0008.0 to L. Norgrove. Some of these data were presented in a preliminary form (written abstract and powerpoint presentation) at the International Conference of Biological Invasions in 2009 with support from CABI and the CABI development fund. Thank you to two anonymous reviewers and the editor who made very helpful comments on an earlier version of this paper. Views expressed are those of the authors and not of their institutes.

Additional information

Notes on contributors

Kim S. Jacobsen

**Current address: Royal Museum for Central Africa, Department of Zoology, Leuvensesteenweg 13, 3080 Tervuren, Belgium

Alphonse Nkakwa Attey

***Current address: 6834 New Hampshire Avenue, Takoma Park, MD 20912, USA.