Survival of Pratylenchus brachyurus under dry soil conditions

Abstract

Pratylenchus brachyurus, a root-lesion nematode, depends on host plants for growth and survival. Weeds, volunteer plants, and crop root residues may act as reservoirs for the parasite in the field, but little is known about the ability of P. brachyurus to survive in the absence of a host. This study aimed to evaluate P. brachyurus survival and infectivity in artificially and naturally infested soil under dry conditions. Two experiments were conducted, the first using artificially infested soil and the second using naturally infested soil. Soil samples were inoculated with a nematode suspension or infected root fragments. At 0, 30, 60, and 90 days post-inoculation, pots were planted with nematode-susceptible maize and soybean. Fallow pots were also analyzed. Nematode survival, infectivity, and morphology were determined 30 days after planting. P. brachyurus showed enhanced survival in soil in the presence of root fragments. However, inoculation method had no effect on the ability of surviving nematodes to infect host roots. Parasites showed signs of anhydrobiosis (C-shaped or tightly coiled body) after 90 and 120 days under dry conditions.

Keywords

• Anhydrobiotic state
• Glycine max
• Root-lesion nematode
• Zea mays
• Rhizosphere
• Crop production