Resistance to Spot Blotch in Barley Germplasm

Multilocation evaluation of barley germplasm accessions for resistance to spot blotch was taken up under artificial epiphytotic conditions in four crop seasons at four locations (Varanasi, Faizabad, Kanpur and Karnal). The lines identified as resistant/moderately resistant from the field screening were again screened in poly house for three more years. Disease data was recorded following the double digit system, indicating the percent area covered on the flag leaf and on the next below to flag leaf on 1 to 9 scale. Out of 5458 accessions screened in the field during four crop seasons, only 28 accessions could be termed as resistant. Another group of 58 accessions was observed as moderately resistant and rest of accessions were in susceptible to highly susceptible group. In order to further confirm their reaction the 86 accessions (resistant and moderately resistant) were screened under controlled conditions of temperature and humidity in poly house with artificial screening at Karnal. Out of the 86 accession 68 were observed as resistant and eight as moderately resistant, while rest 10 were either moderately susceptible or susceptible. The genotypes grouped as resistant were able to keep the disease level on the plant at very low level. These accessions may carry diverse resistance genes, making them useful for breeding programme. The study will provide opportunity for increased utilization of genetic resources maintained in active collection.