Downy mildew incidence on pearl millet cultivars and pathogenic variability among isolates of Sclerospora graminicola in RajasthanV PRaoauthorR PThakurauthorK NRaiauthorY KSharmaauthor Downy mildew (DM; caused by S. graminicola) incidence was evaluated during the rainy seasons of 2001-04 in 585 pearl millet (Pennisetum glaucum) fields in 16 districts of Rajasthan, India. The virulence of 12 S. graminicola isolates from 4 districts of western Rajasthan (Barmer, Bikaner, Churu and Jodhpur) and 3 controls (Sg 139, Sg 212 and Sg 409 from Jodhpur, Durgapura and Patancheru) on 7 pearl millet lines (IP 18292, IP 18293, P 7-4, P 310-17, 700651, 852B and ICMP 451) was also evaluated under greenhouse conditions. Of the 585 pearl millet fields, 59% were infected by DM. The mean DM incidence varied from low to moderate (1-21%) in 14 districts; DM was not recorded in Alwar and Karauli districts. Of the 26 hybrids encountered during the survey, 6 hybrids (Pusa 23, JKBH 26, Proagro 9444, Pioneer 7688, PAC 931 and HHB 67) were highly resistant (mean DM incidence of less than or equal to 5%) and 13 hybrids were disease-free. Generally, DM incidence was higher in hybrids in Sikar, Churu, Jodhpur and Barmer. In the pathogenicity test, the DM incidence varied from 2 to 100% across isolate x host combinations. Of the 15 isolates evaluated, 7 (Sg 138, Sg 381, Sg 382, Sg 383, Sg 384, Sg 385 and Sg 388) were highly virulent, 2 (Sg 407 and Sg 409) were virulent, 2 (Sg 139 and Sg 145) were moderately virulent and 4 (Sg 144, Sg 148, Sg 212 and Sg 406) were slightly virulent. Sg 384 and Sg 385 from Barmer were the most virulent.Millets2005Article