Genetic characterization of Opaque-2 Maize plants derived from the First Backcross Generation

Abstract

Maize has poor nutritional value due to deficiency of two essential amino acids – tryptophan and lysine. Marker assisted selection in combination with conventional breeding can greatly accelerate the introgression of opaque2 gene into normal maize. Parents of a perspective hybrid HKI287 and HKI1126 were undertaken for conversion to develop a QPM hybrid suitable for Central and other parts of India. Plants were selected for the presence of opaque2 using two markers (phi057 and umc1066) as indicated by the amplified products of 140-160 bp. The phi057 marker identified 36 out of 60 BC1F1 HKI1126 plants (60%) and umc1066 marker identified 24 out of 48 BC1F1 HKI287 plants (50%). Microsatellite markers located on different chromosome were used to characterize the effect of first-generation backcrosses by monitoring the level of homozygosity and the parental genomic recovery. The maximum genome recovery for BC1F1 HKI1126 was 75.2% and for BC1F1 HKI287 77.3%.

Keywords

• backcross
• maize
• microsatellite markers
• genome recovery
• genetic variability