Nematode populations as influenced by Leucaena leucocephala and Flemingia congesta in an alley cropping system

Abstract

study to determine the effect of Flemingia congesta and Leucaena leucocephala hedgerows, as sources of mulch, on the population of nematode species in an alley cropping system was conducted at the Crops Research Institute, Kumasi, Ghana from May 1991 to February 1994. Treatments comprised Leucaena leucocephala and Flemingia congesta hedgerows and a control (no hedgerows), arranged in a randomized complete block design with four replications. Soil samples were taken from both hedgerow and control plots and assessed for nematodes periodically. Plant parasitic nematodes isolated were Meloidogyne spp., Pratylenchus spp., Paratylenchus spp., Helicotylenchus spp., and Rotylenchus spp. Three years after planting of hedgerows, significantly (P<0.05) higher populations of Meloidogyne spp. (367 per 100 g soil), Paratylenchus spp. (92 per 100 g soil), Helicotylenchus spp. (8 per 100 g soil), and Rotylenchus spp. (308 per 100 g soil), were associated with L. leucocephala hedgerows than with Flemingia congesta hedgerows (42, 0, 83, 0 per 100 g soil) and the control (74, 50, 41, 0 per 100 g soil). These results clearly indicate that L. leucocephala is a good host for plant parasitic nematodes. On the other hand, F. congesta has qualities that suppress nematode populations. Thus, in alley cropping, studies on attributes other than improvement of soil fertility should be carried out on the hedgerow plant species before recommendation for adoption.



Ghana Jnl agric. Sci. Vol.31(1) 1998: 21-25