Registration of Pea Germplasm Lines Partially Resistant to Aphanomyces Root Rot for Breeding Fresh or Freezer Pea and Dry Pea Types

Eight germplasm lines of green pea (Pisum sativum L.)-RIL 846-07 (Reg. No. GP-99, PI 660729), RIL 847-08 (Reg. No. GP-100, PI 660730), RIL 847-22 (Reg. No. GP-101, PI 660731), RIL 847-28 (Reg. No. GP-102, PI 660732), RIL 847-45 (Reg. No. GP-103, PI 660733), RIL 847-50 (Reg. No. GP-104, PI 660734), RIL 847-53 (Reg. No. GP-105, PI 660735), and RIL 847-68 (Reg. No. GP-106, PI 660736)-were developed and released jointly by the USDA-ARS, the French National Institute for Agricultural Research (INRA), and North Dakota State University. They were selected from an F-8-derived recombinant inbred line (RIL) population developed from a cross between 'Dark Skin Perfection' and 90-2131. These lines all have high levels of partial resistance to root rot caused by Aphanomyces euteiches Drechs. f. sp. pisi when screened in 12 environments of 10 infested field nurseries across 4 yr and four locations in the USA and France and with two reference isolates in controlled conditions. On the basis of a disease index derived from the 12 environments (location-years), these lines had improved partial resistance compared with either parent. RIL 847-028, RIL 847-050, RIL 847-053, and RIL 847-068 performed better in U.S. field nurseries than in the French nurseries. Conversely, RIL 846-007, RIL 847-008, RIL 847-022, and RIL 847-045 performed better in the French field nurseries than in the U.S. nurseries. The eight lines also have acceptable agronomic characteristics: they have white flowers, straight blunt green pods, and green cotyledons; are clear seeded and semidwarf; and flower at the 14th-16th node in 57-61 d. The release of these germplasms will assist the breeding and development of either smooth-or wrinkle-seeded cultivars for the fresh or freezer pea and dry pea markets, respectively, with improved partial resistance to Aphanomyces root rot.