Supervisory Research Plant Pathologist, USDA/ARS/PWA, Prosser, WA 99350
Plant Pathologist, Oak Park Agricultural Center, Carlow, Ireland
Agronomist, Crop and Food Research, Private Bag 4704, Christchurch, New Zealand
In 1991, 1992, and 1994, 2,936 accessions of Pisum sativum from the USDA Plant Introduction collection were screened under field conditions for resistance to Mycosphaerella pinodes without replication due to seed supply. These trials were conducted at the Oak Park Research Station at Carlow, Ireland, where conditions are highly favorable for disease expression. In 1995, the 157 most resistant accessions were again screened at Carlow and at the Food and Crops Research Station at Gore, New Zealand, in replicated trials. At both locations, disease was severe and ranged from 20 to 100% foliar blight. Five accessions were as resistant as the commercial cultivar Radley at both locations: PI 142441, PI 142442, PI 381132, PI 404221, and PI 413691. No accessions were more resistant than the cultivar Radley.