Techniques for Successfully Establishing Xiphinema index in Dual Culture with Grape

Abstract

Xiphinema index was successfully established in aseptic dual culture with roots of V. rupestris St. George under the following conditions. Surface sterilization was accomplished by using 150 mL of 250 000 U/L penicillin + 250 mg/L streptomycin + 0.625 mg/L amphotericin B (Sigma antibiotic/antimycotic compound) solution to wash the nematodes as they settled through a Baermann funnel. After three hours in this solution, the nematodes were rinsed three times with filtered sterile tap water and transferred to petri plates containing V. rupestris St. George roots. The culture media that allowed survival, feeding, and reproduction of X. index consisted of x or x Nitsch and Nitsch salts and vitamins with 15 g/L sucrose and 6 g/L agar. The inoculated excised roots were cultured in the dark. Other surface sterilants tested for their effect on X. index survival prior to establishment in dual culture with grape roots included: NaOCl; NaN₃; chlorexidine; and streptomycin sulfate + HgCl₂. Selected combinations of these materials were tested and none allowed the nematodes to survive in culture longer than four days.