Introduction

CDC Tollefson is a field pea (Pisum sativum L.) cultivar developed by the Crop Development Centre (CDC), University of Saskatchewan (SK, Canada). It is named after Torvald (Torie) and Margaret (Marg) Tollefson who were strong financial supporters of the College of Agriculture and Bioresources, University of Saskatchewan. During their lives, they established multiple renewable entrance scholarships for students at the college. Torvald received a Diploma in Agriculture in 1936 and a Bachelor of Science in Agriculture degree in 1942. He died in 2009. Margaret Tollesfon’s estate made an additional gift to the college in 2015, which will support these awards in perpetuity. CDC Tollefson was issued registration number 9203 on 12 Feb. 2021 by the Canadian Food Inspection Agency, Variety Registration Office.

Breeding Methods and Pedigree

CDC Tollefson was developed from the cross CDC 2648-21//MP1899/2847-21 made in 2011. CDC 2648-21 was a high yielding F₈ breeding line from the CDC’s pea breeding program. Line 2847-21 was later registered as CDC Inca (Warkentin et al. 2018). MP1899 is from the Agriculture and Agri-Food Canada program in Lacombe and was later registered as AAC Lacombe (Bing et al. 2014).

The objective of this cross was the development of a high yielding cultivar with good lodging resistance and medium seed size. Selection for seed size and shape was conducted in the F₁ and F₂ generations in Saskatoon, SK. The F_2:3 family was evaluated in field trials in Saskatoon in 2013. Preliminary replicated yield trials were conducted in the F₄ in Rosthern and Meath Park, SK, in 2014. An F₄ line, 4947-2, was selected based on good yield and good lodging resistance. This line was evaluated in replicated yield trials in Saskatoon, Rosthern, Scott, Kamsack, and Limerick, SK, and Lacombe, Alberta, in 2015, then in 2016 at the same five Saskatchewan locations plus Lucky Lake and Meath Park, SK, and Vegreville, Namao, and Barrhead, AB. It was then entered as CDC 4947-2, an F_2:7 line, in the Field Pea Co-operative (Co-op) Registration Test-A in 2017 and 2018. The Co-op trials were conducted by the following organizations at the following locations: British Columbia Ministry of Agriculture research site at Fort St. John, British Columbia, Alberta Agriculture and Forestry research sites at Brooks, Barrhead, Morinville, and Vegreville, AB, University of Saskatchewan in Saskatoon, Limerick, and Kamsack, SK, Agriculture and Agri-Food Canada (AAFC) Research Centres located in Indian Head, Scott, Melfort, and Swift Current, SK, Lacombe, AB, and Brandon, Manitoba, with disease evaluation at AAFC Lethbridge, AB and University of Saskatchewan, Saskatoon, SK. Breeder seed of CDC 4947-2, later named CDC Tollefson, was derived by bulking 19 F_6:9 lines in 2019, after discarding phenotypic outliers.

Performance

In 2 yr of testing in the Field Pea Co-operative Test-A (24 site-years), CDC Tollefson had significantly greater yield than the check cultivars CDC Amarillo and AAC Lacombe (Table 1), i.e., 108% of the mean of these two checks. CDC Tollefson was 2 d later maturing on average than the checks, with longer vines than both checks. CDC Tollefson had similar lodging resistance as both checks. CDC Tollefson had intermediate seed weight compared with the checks, and seed shape was similarly round as the checks. Seed protein concentration of CDC Tollefson was similar to CDC Amarillo, slightly greater than AAC Lacombe. CDC Tollefson had lower percent seed coat breakage than both checks. CDC Tollefson is adapted to the field pea growing region of western Canada.

Table 1.

Summary of agronomic, quality, and disease data for CDC Tollefson and yellow cotyledon check cultivars CDC Amarillo and AAC Lacombe for all station-years based on data from Field Pea Co-operative Test-A in western Canada, 2017–2018.

Other Characteristics

CDC Tollefson has a semi-leafless leaf type, white flowers, yellow cotyledons, opaque seed coat and round, smooth seed. CDC Tollefson was evaluated in mist-irrigated field disease nurseries at Lethbridge and Saskatoon as part of the Field Pea Co-operative Registration Test in 2017 and 2018. CDC Tollefson was rated as resistant to powdery mildew (Erysiphe pisi var. pisi), as were CDC Amarillo and AAC Lacombe (Table 1). CDC Tollefson was moderately susceptible to Mycosphaerella blight [Mycosphaerella pinodes (Berk. & Bloxam) Vestergren], but with lower disease score than CDC Amarillo in AB, and lower disease score than both checks in SK (Table 1). CDC Tollefson was moderately susceptible to Fusarium root rot (multiple Fusarium species), similar to the checks (Table 1).

Availability of Propagating Material

Breeder seed of CDC Tollefson is maintained by the Crop Development Centre, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, Canada, S7N 5A8. Distribution rights for CDC Tollefson are held by the Saskatchewan Pulse Growers (207-116 Research Drive, Saskatoon, SK, Canada, S7N 3R3). Breeder seed of CDC Tollefson was first distributed in 2021 to seed growers qualified as Select seed growers by the Canadian Seed Growers’ Association.