Effect of rotation of cowpea (Vigna unguiculata) with fonio (Digitaria exilis) and millet (Pennisetum glaucum) on Macrophomina phaseolina densities and cowpea yield

Ndiaye, M. and Termorshuizen, A.J. and Bruggen, A.H.C.van (2008) Effect of rotation of cowpea (Vigna unguiculata) with fonio (Digitaria exilis) and millet (Pennisetum glaucum) on Macrophomina phaseolina densities and cowpea yield. African Journal of Agricultural Research , 3 (1). pp. 37-43.

[img] PDF
Restricted to ICRISAT researchers only

Abstract

Macrophomina phaseolina, the causal agent of charcoal rot, causes great damage to cowpea in the Sahel. One of the few options to manage the disease is by cropping nonhosts that may reduce the soil inoculum below a damage threshold level. To test this, fonio (Digitaria exilis) and millet (Pennisetum glaucum) were cropped continuously for 3 years in plots with a natural infestation of 24-53 microsclerotia g-1 soil at the onset of the experiment. Next, a susceptible cowpea variety was grown to quantify disease incidence and severity on these soils. Fonio and millet both reduced microsclerotial densities in soils from the first year onwards. Reductions under fonio (81% after the 2nd year; 86% after the 3rd year) were significantly stronger than under millet (56 and 66% for the 2nd and 3rd year respectively). Fonio was not infected by M. phaseolina, while the root systems of millet had low densities of microsclerotia. Cowpea yielded significantly more hay and pods after 3 years of fonio than of millet. Cowpea yields and disease incidence (dead plants) could be explained well by pre-planting microsclerotial densities. We conclude that rotation of cowpea with a gramineous crop may lead to a relatively fast decline of inoculum density. In the case of a high inoculum density, fonio can be grown for three years to reduce M. phaseolina densities in soil.

Item Type: Article
Author Affiliation: Centre Régional AGRYMET, Département de Formation et de Recherche, BP. 12625 Niamey, Nigeria
Subjects: Plant Production
Divisions: Millet
Depositing User: Mr B Krishnamurthy
Date Deposited: 20 Dec 2010 17:46
Last Modified: 29 Dec 2010 19:41
Official URL: http://www.academicjournals.org/ajar/PDF/pdf%20200...
URI: http://eprints.icrisat.ac.in/id/eprint/1067

Actions (login required)

View Item View Item