GENOTYPE BY ENVIRONMENT ANALYSIS OF THE PERFORMANCE OF TWO LOW PHYTATE PEA LINES

Abstract

Reducing phytate concentration in crops may result in an increase in the bioavailability of phosphorus and micronutrients and create more environmentally friendly production. Two low-phytate pea lines (1-2347-144 and 1-150-81) were recently developed at the University of Saskatchewan. These lines were grown in field trials at three diverse locations in Saskatchewan in 2009 and 2010 in comparison to CDC Bronco, the parent variety, and two other widely grown varieties (CDC Golden and Cutlass). The low-phytate lines had similar seedling emergence counts, plant height, mycosphaerella blight score and lodging score when compared with CDC Bronco. The low-phytate lines had somewhat later days to flowering and days to maturity, and somewhat lower grain yield and seed weight than CDC Bronco. Harvested seeds of the low-phytate lines had substantially higher inorganic phosphorus (1.21-1.28 mg/g) concentration than CDC Bronco (0.24-0.25 mg/g) and the other normal-phytate varieties. The concentration of phytate phosphorus was reduced in low-phytate lines by about 60% of CDC Bronco. The total phosphorus concentration was similar in all lines and ranged from 3.50-3.80 mg/g. The low-phytate lines had similar Se concentration, but slightly higher Zn and Fe concentration than CDC Bronco. Crude protein concentration was significantly higher than CDC Bronco, while ether extract, acid detergent fibre, neutral detergent fibre and starch concentrations did not differ significantly between the low-phytate lines and CDC Bronco. The low-phytate lines had germination rates similar to CDC Bronco under normal conditions; however, their germination rate was reduced after the seeds had been stressed by accelerated aging or cold treatment.