Impact of the root-lesion nematode Pratylenchus goodeyi and mulch on the East African Highland banana crop performance in Kibuye, Western Rwanda

The effect of nematode root injuries on banana crop yield is very poorly known in higher parts of the East African highlands. This study assessed the impact of the root-lesion nematode, Pratylenchus goodeyi, on growth and yield of three banana cultivars (Musa spp. AAA-EA) in a field experiment involving nematicide and mulch applications at conditions of high altitude (about 1500 m). Plant growth, yield, root damage and nematode population densities were observed over three production cycles. Low to medium levels (<= 50%) of root necrosis were associated with improved plant growth, whilst higher root necrosis (>50%) had no effect on plant growth. No significant reduction in bunch weight was associated with high root necrosis in any cycle and any of the three cultivars. Mulch significantly reduced root necrosis and P. goodeyi population densities. Bunch weight significantly increased in all mulched plots irrespective of root necrosis intensity. These results agree with those of earlier surveys in Rwanda that suggested little impact of P. goodeyi on banana yields. However, they challenge general perceptions and previous findings on the negative impact of root lesion nematodes on banana crop performance.