Archives of Current Research International

Aims: To screen soybean genotypes for their field reaction to yellow mosaic disease (YMD) caused by Mungbean yellow mosaic India virus (MYMIV) and to identify stable, field-validated sources of resistance for use in soybean improvement programmes.

Study Design: Field screening of sixteen soybean genotypes using the infector-row technique to ensure uniform, whitefly-mediated disease pressure across entries.

Place and Duration of Study: ICAR-Indian Agricultural Research Institute (IARI), New Delhi, a recognised YMD hotspot, during the kharif season.

Methodology: Disease incidence (DI) was recorded at 30, 45 and 60 days after sowing (DAS) and disease severity (DS) at 45 and 60 DAS, from which the coefficient of infection (CI) and area under the disease progress curve (AUDPC) were derived for each of the sixteen genotypes.

Results: Genotypes varied widely in their reaction, with CI ranging from 0.0 to 95.7 and AUDPC from 0 to 2497 %-days. Four genotypes – DS 3106, KDS 921, KDS 980 and KDS 1045 – remained free of visible symptoms throughout the crop season (CI = 0), while DS 3105 and SL 1104 showed only mild, localised symptoms (CI < 3) and were classed as highly resistant. In contrast, ten genotypes, including MACS-1520, NRC125 and RSC 10-70, developed rapid, severe infection by 45–60 DAS and were classed as highly susceptible (CI ≥ 69).

Conclusion: The clear separation between resistant and susceptible groups, evident in both the CI ranking and the AUDPC-based disease progress curves, indicates that DS 3105, DS 3106 and SL 1104 are promising, field-validated sources of YMD resistance for use in soybean improvement programmes targeting durable resistance to MYMIV.