EFFECTS OF Meloidogyne incognita INOCULUM DENSITY AND APPLICATION RATE OF Paecilomyces lilacinus ON BIOCONTROL EFFICACY OF BIOAGENT AGAINST ROOT KNOT OF BRINJAL

Abstract

The experiment was conducted in shade house of Department of Plant Pathology, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh, during the period from October 2011 to May 2013 to study effects of Meloidogyne incognita inoculum density and application rate of Paecilomyces lilacinus on biocontrol efficacy of bioagent against root knot nematode of brinjal. Four doses of Paecilomyces lilacinus, viz., 0 CFU/g soil, 1×10 5 CFU/g soil, 5×10 5 CFU/g soil, 1×10 6 CFU/g soil and five inoculum level of M. incognita, viz., 0 eggs/100 cm 3 of soil, 400 eggs/100 cm of soil, 800 eggs/100 cm 3 of soil, 1600 eggs/100 cm 3 of soil, and 3200 eggs/100 cm of soil were used to conduct this experiment. The experiment was laid out in Randomized Complete Block Design 5 CFU/g soil enhance plant growth parameters. Inoculation of Meloidogyne incognita reduced plant growth and the reduction was increased with the increase of inoculum density of Meloidogyne incognita. Maximum plant growth reduction was recorded when 3200 eggs/100 cm 3 of soil was inoculated. The maximum plant growth was recorded in a combined application of Paecilomyces lilacinus 1×10 5 CFU/g soil with 400 eggs of Meloidogyne incognita/100 cm of soil. Minimum gall index

6 CFU/g soil when crop was challenged with Meloidogyne incognita

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3 3 3 3 @ 400 eggs/100 cm 3 of soil. The highest reproduction factor 3 of soil. Application of 5×10 CFU/g soil of Paecilomyces lilacinus resulted lowest reproduction factor of soil. The application of P. lilacinus @ 1×10 6 CFU per g soil reduced máximum 72% gall index and 84% egg masses when the crop was challenged with 800 eggs/100 cm soil. The dose 5×10 5 CFU/g soil of P. lilacinus showed effectiveness to reduce reproduction factor of M. incognita upto 89.6 and 85% when the crop was challenged with 800 eggs and 3200 eggs of the pest/100 cm 3 soil, respectively. 5 3 3