Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Transmission of Bipolaris sorokiniana from seeds to wheat coleoptile.

Abstract

Seeds of the cv. Anahuac with 16-90.5% natural infection by B. sorokiniana (Cochliobolus sativus) and treated or not with iprodione + thiram (50 + 150 g/100 kg seeds) were sown in sand in the greenhouse or in soil in the field. The transmission index was variable, higher values corresponding to higher seed contamination and/or infection indices. The correlation between incidence on the seeds and transmission to seedling coleoptiles was positive and significant, both in the field (r=0.985**) and greenhouse (r=0.923**). With untreated seeds, the av. transmission was 66% (transmission index 1.54:1) and with treated seeds 32% (1.92:1). A transmission index of 1.1:1 was determined for a seed sample with 90.5% natural infection. At a sowing density of 400 viable seeds/m2 this could mean the establishment of 3 290 909 infection foci/ha.