Characterization of mycosphaerella blight resistance, lodging resistance, and micronutrient concentration in a pea recombinant

Characterization of mycosphaerella blight resistance, lodging resistance, and micronutrient concentration in a pea recombinant

The objective of this study is to determine the genetic control of several traits in field pea including mycosphaerella blight resistance, lodging resistance and micronutrient concentration by genotyping and phenotyping a recombinant inbred line population which is segregating for these traits.

Moderate variation for adult plant resistance to mycosphaerella blight, pre-harvest lodging and micronutrient accumulation were observed in field pea. In order to map the quantitative trait loci (QTLs) associated with these traits, a population of 142 F9 recombinant inbred lines (RILs) derived from a cross between Carrera (susceptible to mycosphaerella blight and lodging) and CDC Striker (moderately resistant to mycosphaerella blight and lodging) was phenotyped in Saskatoon and Rosthern, SK, Canada in 2010 and 2011. Based on phenotypic data collected from both 2010 and 2011, area under the disease progress curve (AUDPC) of mycosphaerella blight ranged from 131 to 205 and 143 to 235 for Saskatoon and Rosthern, respectively. At physiological maturity, lodging ratings of the RILs ranged from 3.3 to 7.5 at Saskatoon and 4.5 to 8 at Rosthern. Micronutrient (Se, Zn and Fe) concentrations in the seeds of each RIL were determined using an atomic absorption spectrophotometer for the 2010 samples. A genetic linkage map was generated using 65 SSR (microsatellite) markers resulting in 13 linkage groups that cover 300 cM of the pea genome. A region between AA491 and AA278 on linkage group 13 was identified as putative QTLs associated with mycosphaerella blight, lodging, plant height, Zn and Fe concentrations. All QTLs were derived from CDC Striker, except the one associated with higher Zn concentration which was derived from Carrera.