Vol. 12, Issue 9 (2023)

Author(s):
Dr. Geetika Malik, Dr. Ajmer Singh Dhatt and Dr. Vishal Dinkar

Abstract:
The DNA markers play crucial role in economic and rapid development of CGMS lines in onion. One such marker named PsaO is reported to be linked with nuclear male fertility restorer locus (Ms/ms) in onion. This marker was used to screen three North Indian onion cultivars viz., Punjab Naroya, Punjab Selection and Punjab White already genotyped for cytoplasmic type. The PsaO marker effectively identified various alleles of the locus in all the populations, thereby, ascertaining its ability to reveal polymorphism. However, on morphological scoring, considerable deviations in its allelic frequencies from the frequencies divulged by PsaO were observed. The difference in the observed frequencies for msms allele was 0.25, 0.11 and 0.18 in Punjab Naroya, Punjab Selection and Punjab White, respectively. For Msms, it was 0.30 and 0.06 for Punjab Naroya and Punjab White, respectively, however no deviation for Punjab Selection was observed. For MsMs allele the deviations were 0.05, 0.11 and 0.12 for Punjab Naroya, Punjab Selection and Punjab White, respectively. This reveals a lack of strong linkage between the marker and the gene it has been developed for, with respect to North Indian onion populations. Therefore, the study advocates development of more tightly linked, gene-based, or a functional marker for male fertility restorer locus in North Indian onion.