Marker-trait association in selected Nigerian mini-core pigeonpea [Cajanus cajan (L.) Millsp.] accessions using SCoT markers

Abstract

The pigeonpea [Cajanus cajan (L.) Millsp.] is a popular leguminous plant in the Fabaceae family. Its low yield is a major challenge in Nigeria with no improved varieties developed. The identification of markers linked to agronomical traits will accelerate agronomic yield improvements in pigeonpea. Hence, the study was conducted to identify SCoT markers associated with important agronomic traits within selected Nigerian pigeonpea lines. A total of 52 Nigerian pigeonpea were phenotyped for vegetative and yield traits. DNA was extracted from sampled accessions and evaluated with SCoT markers. Marker performance and association to agronomic traits were evaluated. The coefficient of variation (CoV) varied with agronomical traits, ranging from leaflet length (CoV = 15.77) to tertiary branches (CoV = 155.23). Broad sense heritability was high for all traits (H² > 75%) except for the number of seeds per pod (H² = 9.13%). Genetic advances ranged from 0.65 in leaflet width to 106.65 in pod number. Only seeds per pod showed more environmental variance than the genetic variance. SCoT markers showed 100% polymorphism with average Polymorphic Information Content values > 0.6. The effective marker ratio also ranged between 1.50 in SCoT-3 to 45.38 in SCoT-2. The cumulated phenotypic variance explained by associated markers ranged between 9.11% in 100 seed weight to 44.7% in leaflet width. Some markers were associated with more than one agronomic trait. These markers can be harnessed for their potential application in pigeonpea improvement programmes.