Characterization of downy mildew resistant and susceptible genotypes of pearl millet (Pennisetum glaucum L.) using SDS-page and rapd markers

Protein and DNA profiling of five resistant and two susceptible pearl millet genotypes to downy mildew were investigated. Characterization of total seed proteins using SDS-PAGE was performed. The resistant genotypes had more number of bands (9–14) whereas; susceptible genotypes had fewer bands (4–6). Two bands having Rm values 0.27 and 0.36 were specifically present in all the five resistant genotypes, and were absent in both the susceptible genotypes. The PCR amplification was performed using 120 oligonucleotide decamer primers of arbitrary sequence; however only 14 oligonulcleotide primers yielding more than six PCR fragments were selected. Five PCR fragments obtained in resistant genotypes with OPB 18, OPE 12, OPI 1, OPI 14 and OPK 10 reactions respectively showed its possible linkage with downy mildew resistance gene. The result of protein and DNA profiling suggests suitability of this technique for screening of different pearl millet genotypes against S. graminicola. The development of SCAR can aid in rapid and reliable screening.