A total of 117 wheat genotypes from different zones of India i.e.35 from NEPZ, 34 from CZ, 29 from NWPZ and 19 from PZ were screened for resistance against spot blotch of wheat for three consecutive years (2015-16, 2016-17 and 2017-18) at disease hot spot location, Kalyani, to find out the most suitable varieties for cultivation for this zone. These genotypes were also tested for their stability on disease reactions obtained during three years of testing. The overall analysis of pooled data showed that the genotypes and environment significantly affected the reactions to spot blotch and variation in disease severity was noticed among genotypes and across the environments. The genotype environment interaction was also highly significant for disease severity. This indicated that the spot blotch disease severity in the genotypes has divergent linear responses to environmental changes. Deviation from linear regression has contributed substantially towards differences in stability of disease reactions on genotypes. It was found that both predictable (linear) and unpredictable (non-linear) components contributed to the differences in stability of disease reaction (resistance, moderately resistant/ tolerant) among genotypes. Based on the disease tolerance reaction, out of the 117 tested genotypes, K8027, C306 and Raj4240 from NEPZ; HI8730(d), HI8726(d), MP1259, GW1280(d) and HI1500 from CZ; PBW665 from NWPZ and HI8728(d), HI8725(d), MACS6222, NIDW295(d) and AKAW4731 from PZ could be used to develop improved genotypes with spot blotch resistance which are suitable for Indo-Gangetic plains of India.

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