Background: Sclerotium rolfsii Sacc. is a destructive soil-borne plant pathogen that infects over 500 plant species and causes significant yield losses in many economically important plant species. Synthetic fungicides used to combat the menace also pollute the environment and cause health hazards. In order to search environmental friendly alternatives from natural resources, in the present study, methanolic extracts of three leguminous tree species namely Acacia nilotica (L.) Willd. ex Delile subsp. indica (Benth.) Brenan, Prosopis juliflora (Sw.) DC. and Albizia lebbeck (L.) Benth. were evaluated for their antifungal activity against S. rolfsii. Materials and Methods: Two hundred grams dried leaf material of each of the three test plant species were extracted with methanol for two weeks. After filtration, methanol was evaporated on a rotary evaporator. Malt extract broth was used to make various concentrations of the crude methanolic extracts and their antifungal potential was determined by comparing the fungal biomass in various treatments with control. Chemical composition of methanolic leaf extract of A. nilotica subsp. indica was determined through GC-MS analysis. Results: Methanolic leaf extract of A. nilotica subsp. indica showed the highest fungicidal activity. Fungal biomass was decreased by 17-55% due to various concentrations of this extract over control. Different concentrations of P. juliflora reduced fungal biomass by 3-52%. Fourteen compounds were identified in methanolic extract of A. nilotica subsp. indica. 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z,)- (16.59%) was the most abundant compound followed by 1-pentanol, 2 methyl-, acetate (14.80%); hexanedioic acid, dimethyl ester (13.10%) and cyclotriaconta- 1, 7, 16, 22-tetraone (10.28%). Conclusion: This study concludes that methanolic leaf extract of A. nilotica subsp. indica can be used for management of S. rolfsii.

-Biopower is a commercial rice biofertilizer comprised of various associative nitrogen fixers. In this present study, a field trial was carried out to assess the effects of Biopower application on the growth of some rice weeds and yield of rice (Oryza sativa). Four common rice weeds namely Cyperus rotundus, Echinochloa colonum, Marsilea minuta, Paspalum paspaloides, and mixed weeds were sown in 1:1 weed crop ratio in soil amended with i) ½ dose of N (nitrogen) + recommended doses of PK (phosphorus, potassium) fertilizers, ii) recommended doses of NPK fertilizers, and iii) farmyard manure (FYM) + ¼NPK fertilizers, with and without Biopower application. Biopower application variably reduced weed biomass in different soil amendment systems. The effect of Biopower on weed biomass was most pronounced in NPK, followed by FYM amendment, resulting in up to 50% and 36% reduction in weed biomass, respectively. Biopower application enhanced shoot N content of rice in all the treatments. The effect of Biopower application on shoot N content was most pronounced in ½N-PK and least in NPK applied plots. The four weeds planted with rice reduced rice grain yield by 12-75% in different soil amendments. Biopower application enhanced grain yield in rice, in weed free control, and in different weeds infested plots by 38-90% in ½N-PK, 6-13% in NPK and 12-150% in FYM applied plots. The present study has come to the conclusion that adverse effect of weeds on grain yield of rice can be managed by the application of Biopower in combination with either ½N-PK or FYM amendment.Keywords: associative nitrogen fixers, biofertilizer, weed suppression. RESUMO -Biopower é um biofertilizante comercial para arroz composto de vários fixadores de nitrogênio associativos. Neste estudo, realizou-se um ensaio de campo para avaliar o efeito da aplicação de Biopower no crescimento de algumas plantas daninhas de arroz e na produção de arroz (Oryza sativa). Foram semeadas quatro espécies de plantas daninhas comuns: Cyperus rotundus, Echinochloa colonum, Marsilea minuta e Paspalum paspaloides; plantas daninhas variadas foram semeadas na proporção de 1:1 em solo ajustado com i) meia dose de N (nitrogênio) + doses recomendadas de adubos PK (fósforo, potássio), ii) doses recomendadas de adubos NPK e iii) estrume de quintal + fertilizantes NPK

Collar rot of chili (Capsicum annuum L.) is a very destructive disease caused by a soil-borne fungal pathogen

Sclerotium rolfsii is a polyphagous soil borne fungus infecting more than 500 plant species across the world that is causing vast losses. Although the fungus is soil and seed borne, soil borne inoculum is most vital in infection-causing and syndrome development. Treating soil borne pathogens with fungicides is not reasonable due to very high costs. Environmental hazards are also involved. Therefore, integrated management of pathogens using biological controlling agents is the paramount alternative. Extracts of higher plants have demonstrated a wide range of activity against plant pathogenic organisms. The present research work was carried out to manage the pathogen and disease in vitro by using plant extracts. The antifungal activity of the methanolic leaf extract of two medicinally important indigenous plants, Alstonia scholaris and Azadirachta indica, against the fungal pathogen S. rolfsii was evaluated. In vitro antifungal bioassay was conducted against the S. rolfsii using different concentrations (0, 1, 2 and 5) of the methanolic leaf extract of A. scholaris and A. indica using malt extract (ME) broth as a culture medium. Different concentrations of A. indica leaf extract appreciably reduced the fungal biomass growth up to 76% as compared to the control. In the same manner, various concentrations of the leaf extract of A. scholaris significantly decreased fungal biomass up to 70% as compared to the control. Higher fungal growth was reduced by a 2% concentration of both plants. The present study concludes that the methanolic extract of A. indica has more active antifungal components and can be effectively used to manage phyto-pathogens.