Influence of Incubation Solution on the Rate of Recovery of Pratylenchus brachyurus from Cotton Roots


  • G. W. Bird


The rate of recovery of Pratylenchus brachyurus from cotton roots was enhanced when the tissue was incubated in solutions containing 10 ppm ethoxyethyl mercuric chloride, 50 ppm dihydrostreptomycin sulfate, 50, 100, or 1,000 ppm diisobutylphenoxethyl dimethyl benzyl ammonium chloride, or mixtures of these compounds. Incubation in 10 or 100 ppm zinc sulfate, zinc chloride, or magnesium chloride also enhanced the rate of recovery. Incubation solutions containing 1 or 1,000 ppm zinc chloride or magnesium chloride had no influence on this phenomenon, whereas, 10,000 ppm zinc sulfate, zinc chloride, or magnesium chloride retarded the rate of recovery. A t all incubation intervals during the first 21 days after the roots were removed from soil, the P. brachyurus population consisted of approximately 25% second-stage juveniles, 44% third and fourth-stage juveniles, and 31% females. At least 88% of the second-stage juveniles and 51% of the third and fourth-stage juveniles passed through a single 325-mesh sieve, whereas, 84% of the females collected were retained on a sieve of this mesh. Key Words: Gossypium hirsutum, Extraction, Incubation.