BIOLOGICAL AND SEROLOGICAL VARIABILITY OF ZUCCHINI YELLOW MOSAIC-VIRUS IN SUDAN

Zucchini yellow mosaic potyvirus (ZYMV) is prevalent in different cucu rbit growing agro-ecosystems in Sudan. A study of the biological and s erological variability of isolates originating from different regions was conducted to better understand ZYMV epidemiology and to develop ad apted and durable control strategies. Variability was detected among i solates regarding symptomatology, host range and virulence towards the Zym resistance gene in melon (Cucumis melo L.) PI 414723. Serological variability was also revealed using a set of seven differential monoc lonal antibodies (mAbs) raised against a French isolate (ZYMV-E9). Six serotypes were differentiated, but a majority of isolates (88%) react ed with all the mAbs as did the reference strains from Italy and Franc e. All isolates from Sudan were equally well controlled by the resista nce genes described in squash (Cucurbita moschata (Duchesne) Duchesne ex Poir. cvs. Menina and Nigeria) and in cucumber (Cucumis sativus L. cv. TMG), or by cross protection with the mild ZYMV-WK strain. All iso lates were transmitted in a nonpersistent manner by Aphis gossypii Glo ver and Myzus persicae Sulzer.