Comparative Host Suitability of Selected Crop Species to Tylenchorhynchus zambiensis

摘要

The host suitability of five genotypes of maize (Zea mays), alfalfa (Medicago sativa cv. Cimarron), red clover (Trifolium pratense cv. Mammoth), soybean (Glycine max cv. Bragg), sunflower (Helianthus annus cv. CCA82-2), wheat (Triticum aestivum cv. Pioneer 2508), and white clover (Trifolium repens cv. Dutch White) to Tylenchorhynchus zambiensis were evaluated in two greenhouse experiments. Plants were inoculated with 5 000 nematodes, and populations and effects on growth were determined 60 days later. The host status was determined by calculating a reproductive factor (R) where R = final population (Pf)/initial population (Pi) and where R 1 = nonhost; R = 1.1-4 = poor host; R = 4.1-10 = fair host; R = 10.1-20 = good host; and R 20 = excellent host. Maize genotypes 'MO17 x A634', 'MM603', 'ZM-1760', 'TGR 1349', and 'Natal 8-Row Flint' were excellent hosts for T. zambiensis. Although plant growth was minimally affected by T zambiensis, highest numbers of nematodes per gram of dry roo