DEVELOPMENT OF HETERODERA AVENAE BIOTYPE HA 31 ON RESISTANT BARLEY AND OAT CULTIVARS

Abstract

Development of Heterodera avenae biotype Ha 31 was compared on the resistant cultivars barley C 164 and oat Kent and on the susceptible cultivar wheat C 306. Juveniles (J[sub2]) penetrated each of the cultivars but significantly fewer penetrated the roots of oat. Further development ceased in oat and J[sub2] disintegrated except for the few which were able to develop into normal males. Development in barley roots was normal, but the majority of adult females remained small-sized and failed to extrude from the roots and thus were unable to copulate and reproduce; sex ratio was affected in favour of males. Oat cultivars HFO 114, Kent, OS 6 and OS 7 commonly grown in Haryana state of India were resistant to biotype Ha 31 of H. avenae.