Potential of intercropping napier grass with maize during the establishment phase of napier grass

Abstract

Napier grass (Pennisetum purpureum) serves a variety of functions, which include provision of fodder. However, small scale farmers in East Africa need both food and fooder crops. Hence, research to determne the potential of intercropping napier with maize (Zea mays) is relevant. This was done using a range of spatial arrangements. In a relatively drought season (1999b), when measurements were limited to the rows closest to napier-in order to determine its competition on maize, double napier rows alternating with single maize rows resulted in 55-68% reduction in maize dry matter (DM) production. The reduction in DM production was only 14% for the additive mixture. The reduction in napier biomass yield for the row closest to maize row(s) was significantly greater, 67-73%, in mixures in which 2 maize rows alternated with single napier grass rows. In a better growing season (2000a), maize DM production during the grain filling period was 19-76% lower in mixtures (depending on spatial row arrangement) compared to the pure stands, and the additive mixture did not exhibit reduction in maize DM production until the dough stage. Maize grain yield and yield components in the additive mixture and the 1:3 napier:maize row arrangement were not significantly lower than the sole maize, and maize was the dominant species in the mixtures. It was concluded that during the first phase of napier growth (before regular cutting back for fodder commences) it is possible to superimpose a maize row between the pure stand napier without much reduction in maize yield (only 5%). The reduction in maize yield in the 1:3 napier: maize rows arrangement was also negligible (6%). However, zero-grazing farmers who are more interested in napier biomass and a bonus of maize yield would take the 3:1 row arrangement. The higher maize yield for the additive mixture and the 1:3 mixture compared to the others, during the first phase of napier growth, was attributed to the higher population of maize plants in these mixtures. However, maize in these mixtures was competitive against the young napier plants and reduced its biomass production.