The incidence and distribution of seed-transmitted viruses in pea and lentil seed lots in Ethiopia

Abstract

The incidence of seed-transmitted viruses was determined in 270 lentil and 219 pea seed samples collected in 1998 and 1999 from farmers' seed lots in Ethiopia. Seedlings obtained from 400 seeds from each sample were serologically tested for infection with six viruses. In lentil, 43.7% of the samples had at least one virus. Pea seed-borne mosaic virus (PSbMV, genus Potyvirus, family Potyviridae) was detected in 31.1% of the samples, whereas bean yellow mosaic virus (BYMV, genus Potyvirus, family Potyviridae), broad bean stain virus (BBSV, genus Comovirus, family Comoviridae), alfalfa mosaic virus (AMV, genus Alfamovirus, family Bromoviridae), and cucumber mosaic virus (CMV, genus Cucumovirus, family Bromoviridae) were detected at very low rates. The highest incidence in a single lentil seed sample was 16.8% for PSbMV. Seventy two out of the 158 samples from central Ethiopia (45.6%) were infected with PSbMV, whereas only 12 out of 112 from northern Ethiopia (10.7%) were infected. Of 219 pea seed samples tested for PSbMV, BYMV, CMV, AMV and pea early browning virus (PEBV, genus Tobravirus), only five were infected with PEBV and two with BYMV at a very low rate and none was infected with PSbMV, AMV and CMV. Testing of 40 lentil and 228 pea germplasm accessions from the National Pulse Improvement Program for PSbMV revealed that 15 lentil and 4 pea lines were contaminated.