Chemoattraction of Tylenchorhynchus mashhoodi towards Pigeon pea [Cajanus cajan (L.) Mill.] and factors influencing attraction

Attraction of Tylenchorhynchus mashhoodi towards pigeon pea roots was found positive and factors studied affect the attraction in varying degree. Attraction of T. mashhoodi increased significantly from minimum to maximum when the period of observation was increased from 6 to 24 hrs. Maximum attraction was recorded towards elongation zone of pigeon pea root (1-2cm) while, least towards maturation zone (2–3 cm). The positive and significant correlation was found between attraction of T. mashhoodi and incubation periods of root (r = 0.78, PE(r) = 0.197, p < 0.05). Short (6 hrs) and long period of (24 hrs) incubation of root yielded minimum attraction response. Temperature higher than 30ºC inhibited attraction, whereas maximum attraction was found at 30 ºC. T. mashhoodi were attracted maximally at 1% agar concentration and 2 mm thick agar layer, while minimum attraction was recorded at 4–5% concentrations and 10 mm thick agar layer. The attraction decreased with the increase in their distance of inoculation.