Incidence and control of viruses in Gladiolus in the Netherlands

The control situation of virus diseases in Dutch-grown gladioli was studied. Bean yellow mosiac virus (BYMV), narcissus latent virus (NLV), tobacco rattle virus (TRV), cucumber mosaic virus (CMV), and an unidentified corky pit viruslike agent (UCPVA) were found apart from tobacco mosaic virus (TMV) only found once and from the ca. 20 viruses reported in the literature. Symptoms are extensively described as these affect the mode of control to discard undesirably diseased plants and cultivars. The conn yield reduction by BYMV was little. The virus detection by visual means is considered much more important than the ELISA-testing used for diagnostics only. The BYMV-tested culture of a series of cultivars was unsuccessfull because of the rapid BYMV-spread inefficiently controllable by mineral-oil sprays, and the harmful effect of current-season infection on the quality of cut flowers. The incidence of other viruses, e.g., NLV, CMV, TRV, and the UCPVA is considered effectively reducible by the roguing of plants and the rejection of lots for further use, apart from the soil disinfestation to limit TRV-infection. The general control situation of all viruses apart from BYMV, and the perspectives of virus-tested culture are discussed.