M. Nagesh ¹, P. Parvatha Reddy ¹, N. Rama ¹

Affiliations
1 Division of Entomology and Nematology Indian Institute of Horticultural Research Hessaraghatta Lake P.O., Bangalore 560089, Karnataka, IN

Abstract

Four indigenous antagonistic fungi belonging to 3 species, Gliocladium virens Miller Giddens & Foster, Paecilomyces lilacinus (Thon) Samson, Trichoderina harzianum Rifai and T. viride Pers. Ex S. F. Gray evaluated for their pathogenicity to eggs and egg masses of Meloidogyne incognita, in vitro through the Petri-dish assay and in vivo under glasshouse conditions were found pathogenic. Under both the conditions, maximum egg mass and egg parasitization was observed to be by P. lilacinus followed by T. viride, G. virens and T. harizianum. There was a general decline in parasitization by these fungi, under in vivo conditions compared to that under in vitro conditions. Fungal colonization in galled ischolar_mains was higher than in healthy ischolar_mains. Comparatively T. viride and G. virens recorded higher ischolar_main colonization closely followed by P. lilacinus. Among the four fungi, P. lilacinus recorded consistently higher pathogenicity against ischolar_main-knot nematodes both in vitro and in vivo conditions, indicating that P. lilacinus was more efficient against ischolar_main-knot nematodes compared to other species.

Keywords

Antagonistic Fungi, Meloidogyne incognita, Pathogenicity.

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M. Nagesh ¹, P. Parvatha Reddy ¹, N. Rama ¹

Affiliations
1 Division of Entomology and Nematology Indian Institute of Horticultural Research, Hessaraghatta Lake P.O., Bangalore 560089, Karnataka, IN

Abstract

A laboratory experiment was carried out to identify optimum formulation medium and temperature for storage of Paecilomyces lilacinus based on spore viability. Paecilomyces lilacinus spores were produced on PDA, paddy grain, sorghum grain and tapioca broth, formulated on coconut coir pith, talc and vermiculite and stored at 0, 15 and 27 ± 1°C for 150 days, with P. lilacinus spores stored at -20°C on sterile silica grain as control. In general, the spore viability in grain based formulations (paddy and sorgbum) declined more rapidly than on tapioca broth based formulations. The spores stored at -20°C on sterile silica grain recorded 98 per cent viability even at 150^th day of storage. Spores formulated on tapioca broth with talc, vermiculite or coir pith as inert base, and on paddy grain with talc as inert base, exhibited more tban 80 per cent viability at 150 days of storage at ooe temperature which declined to ≥60 per cent at 27 ± 1°C after 150 days of storage.

Keywords

Formulations, Paecilomyces lilacinus, Spore Viability, Storage Temperatures.

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M. Nagesh ¹, P. Parvatha Reddy ¹

Affiliations
1 Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessaraghatta Lake P.O., Bangalore 560089, Karnataka, IN

Abstract

A simple method to mass multiply Pasteuria penetrans (Thorne) Sayre&Starr an obligate parasite of plant parasitic nematodes, was worked out by modifying the method defined by Stirling and Wachtel (1980). With the increase in seed rate/pot, there was an increase in ischolar_main content/pot and number of Meloidogyne incognita (Kofoide&White) Chitwood females which in turn contributed to an increase in number of infected females and spore number/g ischolar_main. This method not only enhanced spore production efficiency/pot but also reduced the inherent disadvantage of maintaining and handling a large number of plants under individual pot (in vivo) conditions.

Keywords

Eggplant, Mass Multiplication, Meloidogyne incognita, Pasteuria penetrans.

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M. Nagesh ¹, P. Parvatha Reddy ¹

Affiliations
1 Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessaraghatta Lake P.O., Bangalore-560 089, IN

Abstract

Investigations were conducted on the management of the ischolar_main-knot nematode, Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949 infecting crossandra, by integrating the use of two biocontrol agents viz., Paecilomyces lilacinus (Thom.) Samson and Verticillium lecanii (A. Zimmerman) Viegas with leaf extracts of castor and neem (5% each) as bare ischolar_main dip and soil drench. Combinations of V. lecanii and P. lilacinus (2 × 10⁴ spores/ml each) with 5% neem leaf extract resulted in significantly higher plant growth parameters and flower yield. Root gall index was least under V. lecanii plus neem leaf extract (5%) combination followed by V. lecanii plus castor leaf extract (5%). The per cent egg and egg mass parasitization were higher in P. lilacinus than in V. lecanii when they were employed singly without any leaf extract combinations. However, integration with castor leaf extract enhanced the fungal parasitization by P. lilacinus more than that by V. lecanii. Integration with neem leaf extract improved the parasitization by V. lecanii more than that by P. lilacinus.

Keywords

Bare Root Dip, Castor, Crossandra, Leaf Extracts, Meloidogyne incognita, Neem, Paecilomyces lilacinus, Soil Drench, Verticillium lecanii.

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