MANOJ KUMAR, VGUNASRI, REDDI2018-08-082018-08-082017http://krishikosh.egranth.ac.in/handle/1/5810063750D5445Investigations on “Studies on the management of fungal foliar diseases of blackgram [Vigna mungo (L.) Hepper] in Guntur district of Andhra Pradesh” was carried out in the Agricultural College Farm, Bapatla, Guntur district, Andhra Pradesh during rabi, 2016-17. A survey was conducted during rabi, 2016-17 in Guntur district of Andhra Pradesh to record the occurrence and severity of fungal foliar diseases at 30-35, 40-45 and 50-55 DAS. Two mandals were selected based on the preceding year blackgram cultivation statistics, in each mandal two villages and in each village two fields were surveyed. There was no record of any fungal foliar disease at 30-35 DAS. At 45-50 DAS, overall mean PDI of Corynespora leaf spot (Corynespora cassiicola) PDI was 31.89% and at 50-55 DAS it was 67.27%. The overall mean PDI of Cercospora leaf spot (Cercospora canescens) at 40-45 DAS was 28.88% and at 50-55 DAS it was 53.70%. The overall mean PDI of powdery mildew (Erysiphe polygoni) at 40-45 DAS was 22.85% and 63.22% at 50-55 DAS. During rabi, 2016-17, Corynespora leaf spot PDI of six genotypes viz., LBG 752 (r= -0.635), LBG 709 (r=-0.656), KU-15-6 (r= -0.637), LBG 20 (r= -0.640), LBG 791 (r= -0. 648) and LBG 685 (r= -0.654) showed a significant negative correlation with mean minimum temperature. Cercospora leaf spot PDI of three genotypes viz., LBG 752 (r= -0.642), LBG 709 (r=-0.660) and T9 (r= -0.636) showed a significant negative correlation with mean minimum temperature. Powdery mildew PDI of six genotyes LBG 752 (r= -0.654), KU-15-3 (r=-0.655), LBG 709 (r=-0.664), KU-15-6 (r= -0.678), LBG 791 (r= -0.650) and PU 31 (r= -0.633) showed significant negative correlation with minimum temperature. Regression analysis for PDI of Corynespora leaf spot, Cercospora leaf spot and powdery mildew revealed that maximum temperature and minimum temperature influenced the development of the disease in all the genotypes. Out of 16 genotypes (including check) evaluated for their reaction to fungal foliar diseases, two genotypes T9 and LBG 645 were moderately resistant to Corynespora leaf spot. The genotype LBG 645 was rated as moderately resistant to Cercospora leaf spot. Ten genotypes viz., LBG 20, LBG 791, LBG 685, LBG 645, LBG 787, PU31, LBG 790, KU-15-13, LBG 792 and T9 were categorized as moderately resistant to powdery mildew. Studies on the management of fugal foliar diseases with fungicides have revealed that two sprays of Azoxystrobin 23 SC @ 0.05% has recorded significantly lowest severity of Corynespora leaf spot (53.52%). Carbendazim 50 WP @ 0.05% has significantly reduced the Cercospora leaf spot severity (33.75%). Trifloxystrobin 25% WG + Tebuconazole 50% WG @ 0.05% has absolutely controlled (0%) the powdery mildew. Highest seed yield (9.33 q ha-1 ), highest test weight (6.40 g), highest B:C ratio (1.72), lowest per cent seed discolouration and per cent shrivelled seed were recorded with Azoxystrobin 23 SC @ 0.05%.en-USnullThesis