Evaluation of Trichoderma and garlic clove extract against Sclerotinia sclerotiorum of Brassica juncea.

摘要

Preliminary laboratory studies were conducted to manage Sclerotinia rot of Indian mustard caused by S. sclerotiorum using Trichoderma spp. and garlic clove extract. Six species of Trichoderma (T. harzianum, T. viride, T. hamatum, T. reesei, T. piluliferum and T. virens) were evaluated for their efficacy against the pathogen on potato dextrose agar (PDA) medium by using dual culture method. T. hamatum, followed by T. harzianum, proved significantly superior in reducing mycelial growth and sclerotial production of the test pathogen, which were recorded after 3, 5, 7 and 10 days of incubation (DOI). The percentage inhibition of mycelial growth of S. sclerotiorum by T. hamatum at 3, 5, 7 and 10 DOI was 59.2, 57.8, 56.7 and 56.1%, respectively. T. harzianum exhibited 47.2, 45.0, 44.4 and 42.8% inhibition of mycelial growth at 3, 5, 7 and 10 DOI, respectively. The inhibition of sclerotial production was maximum in T. harzianum (100%), followed by T. hamatum (83.9%), after 10 days of incubation. The mycelial growth and sclerotial formation of the pathogen on aqueous garlic clove extract (2%)-amended PDA were recorded after 2, 3, 4, 6 and 10 DOI. The aqueous garlic clove extract (2%)-amended PDA provided 100% inhibition of growth of the pathogen up to 2 DOI. The percentage mycelial inhibition was 86.3, 73.9 and 34.6 after 3, 4 and 6 DOI, respectively. The sclerotial formation in garlic clove extract (2%)-amended PDA plates initiated after 6 DOI, whereas in the control it started after 4 DOI.