Author: A.A.M. DAWABAH, A.S. AL-HAZMI AND S. AL-SHAWY

Publishing Date: 2007

E-ISSN: 0255-7576

Volume 25 Issue 2

ABSTRACT:

Cereal cyst nematode, Heterodera avenae Wollenweber, 1924, is the most important pest limiting the productivity of wheat and barley in Saudi Arabia (Al-Hazmi et al., 1999; Ibrahim et al., 1999). Until now, the nematode has not been recorded on any other host plants except for wheat and barley in Saudi Arabia. However, during a routing study of wheat fields in the Hail region, white females and cysts of H. avenae were found on the roots of the Italian rye grass, Lolium multiflorum Lam., (known in Saudi Arabia as Multimo grass and cultivated as a fodder crop), and wild or foxtail barley, Hordeum murinum L., (a tufted annual grass that appears widely in winter) which appeared as new host records in Saudi Arabia. The detected nematode was initially identified as H. avenae using the keys of Mulvey & Golden (1983) and Golden (1986). Identification was then reconfirmed by morphological and morphometric studies based on cyst vulvar cone structures and measurements, as well as morphometric features of second stage juveniles (J2), males and gravid females.