S. Ramakrishnan ¹, M. Nagesh ²

Affiliations
1 CTRI Research Station, Hunsur, Karnataka, IN
2 National Bureau of Agriculturally Important Insects, Bangalore 560 024, Karnataka, IN

Abstract

FCV tobacco is an important commercial crop grown in Karnataka under rain fed situations. Root-knot nematode is a limiting factor causing yield reduction in both nursery and main field crop to the tune of 59.4% and 52.9%, respectively. As an alternative to nematicides of chemical origin, beneficial fungi such as Paecilomyces lilacinus and Glomus fasciculatum were evaluated along with organic amendments viz., neem cake and vermicompost as individual application and also in rational combinations against Meloidogyne incognita in FCV tobacco nurseries. Results revealed that application of P. lilacinus strain NBAII PLFT5 @ 100g/m² recorded 31.3% increase in healthy transplants compared to check. Combined application of P. lilacinus with neem cake @ 1kg/m² recorded 34.4% increase in healthy transplants count and was on par with P. lilacinus with vermicompost @ 1kg/m². Application of P. lilacinus + neem cake @ 1kg/m² and P. lilacinus + vermicompost @ 1kg/m² significantly reduced ischolar_main-knot index to 1.89 compared to 2.05 in carbofuran @ 50g/m² treated beds (standard chemical check) and 3.86 in untreated check. Similarly, these two treatments were on par with each other in significantly reducing the number of egg masses/g ischolar_main and final soil nematode population.

Keywords

Bio-management, Glomus fasciculatum, Paecilomyces lilacinus, Root-knot Nematode, FCV Tobacco, Neem Cake, Vermicompost.

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M. Seema ¹, S. Ramakrishnan ², S. S. Sreenivas ², N. S. Devaki ¹

Affiliations
1 Department of Molecular Biology, Yuvaraja's College, University of Mysore, Mysore 570 005, Karnataka, IN
2 Central Tobacco Research Institute, Hunsur, Karnataka, IN

Abstract

Studies were conducted during 2009–10 to 2010–11 to evaluate talc and neem cake formulations of Trichoderma viride for controlling sore shin disease in FCV tobacco nurseries incited by Rhizoctonia solani. The pooled data analysis of two years indicated that T. viride in neem cake formulation was more effective than the talc formulation and reduced sore shin disease by 63.53%. This effective bio-intensive module reflected on the better yield of healthy transplants (835 m⁻²) as against untreated (489 m⁻²) check. The schedule gave an Incremental Cost Benefit Ratio (ICBR) of 1:10.27.

Keywords

Rhizoctonia solani, FCV Tobacco, Hore Shin, Trichoderma viride.

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S. Ramakrishnan ¹, G. Rajendran ²

Affiliations
1 Central Tobacco Research Institute, Research Station, Hunsur 571105, Karnataka, IN
2 Department of Plant Nematology, Tamil Nadu Agricultural University, Coimbatore 641003, Tamil Nadu, IN

Abstract

Studies on evaluation of biocontrol agents against Meloidogyne arenaria on groundnut under glasshouse conditions revealed that application of Pseudomonas fluorescens as seed treatment+soil application recorded significant increase in plant growth characters and groundnut pod yield compared to untreated control. Groundnut plants treated with P. fluorescens as both seed treatment+soil application recorded least number of galls/plant, egg mass/plant, eggs/egg-mass and soil population/200 g soil with corresponding reduction of 70.9, 34.4, 20.3 and 68.1 per cent, respectively, over untreated control. It was followed by P. fluorescens as soil application alone and carbofuran in reducing the ischolar_main knot nematode infection in groundnut.

Keywords

Meloidogyne arenaria, Pseudomonas fluorescens, Trichoderma viride, Groundnut, Seed and Soil Treatment.

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J. Jayakumar ¹, S. Ramakrishnan ²

Affiliations
1 Department of Nematology, Tamil Nadu Agricultural University, Coimbatore 641003, Tamil Nadu, IN
2 Central Tobacco Research Institute, Research Station, Hunsur 571105, Karnataka, IN

Abstract

Studies on compatibility of avermectin with carbofuran 3G, Pseudomonas fluorescens and Trichoderma viride for the management of Meloidogyne incognita in tomato revealed that combination of seedling ischolar_main dip with avermectin 75% and soil application of carbofuran 3G @ 1kg a.i ha-1 recorded maximum shoot length of 36.90cm, fresh shoot weight of 16.80 g, dry shoot weight of 5.2g, and fruit yield of 290.50g / plant. It was followed by avermectin + P. fluorescens and avermectin + T. viride. Maximum reduction in number of M. incognita adult females (14.33), number of egg masses/g ischolar_main (6.33), number of eggs per egg mass (105.33), soil nematode population (105.67) and ischolar_main knot index (1.0) was recorded in plants treated with avermectin + carbofuran 3G, followed by combined application of avermectin with P. fluorescens or T. viride.

Keywords

Avermectin, Meloidogyne incognita, Nematicide Combination, Tomato.

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S. Ramakrishnan ¹, S. S. Sreenivas ¹

Affiliations
1 Central Tobacco Research Institute Research Station, Hunsur 571 105, Karnataka, IN

Abstract

Flue Cured Virginia (FCV) tobacco is a major rain-fed crop grown in light soil regions of Karnataka. Fusarium wilt disease complex caused by Fusarium oxysporum f. sp. nicotianae in association with Root-knot nematodes, Meloidogyne incognita is a major threat to the successful production and also for its sustainability in the region. The tobacco crop affected with above malady exhibit stunted growth, severe wilt symptoms, drying of leaves on one side of the plant and with conspicuous galls on the infected ischolar_mains resulted in heavy yield and quality loss. Fungicides and nematicides are being used against this wilt disease complex with limited efficacy. Extensive use of pesticides of chemical origin especially in higher doses for disaese control has to be avoided due to higher costs and associated hazards to the environment. Replicated trials were conducted with antagonistic bacterium, Pseudomonas fluorescens and antagonistic fungi, Aspergillus niger singly and in combinations against fusarium wilt disease complex in FCV tobacco under sick field conditions. Results revealed that application of P. fluorescens @ 1g/plant in combination with A. niger enriched with FYM @ 100 g /plant at the time of planting resulted in 61.0% reduction in fusarium wilt disease incidence at 70 DAT compared to untreated check. There was significant reduction in ischolar_main knot nematode incidence in terms of RKI (Root- Knot Index) to 1.93 and final soil nematode population to 72.5 as compared to RKI of 3.71 and final soil nematode population of 140 in untreated check. Subsequent increase in total cured leaf and bright grade yield was 1311 kg/ha and 926 kg/ha respectively as compared to 1042 kg/ha and 615 kg/ha respectively in untreated check.

Keywords

Pseudomonas fluorescens, Aspergillus niger, FusariumWilt Complex, Meloidogyne incognita, FCV Tobacco.

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S. Ramakrishnan ¹, C. V. Sivakumar ¹, K. Poornima ¹

Affiliations
1 Department of Nematology, Tamil Nadu Agricultural University, Coimbatore 641 003, Tamil Nadu, IN

Abstract

Field experiments were conducted with rice cvs. C043, DT36 and ADT 38 during Kuruvai (June-September); Samba (August- January), and Navarai (January-April) seasons, respectively, to evaluate the efficacy of plant growth promoting rhizobacterium, Pseudomonas fluorescens Migula strain Pf-1 available with Tamil Nadu Agricultural University, Coimbatore, as commercial formulation in the control of the rice ischolar_main nematode Hirschmanniella gracilis (de Man) Luc & Goodey. The biocontrol agent was evaluated as seed treatment and nursery soil application separately and either with or without soil application of carbofuran 3G and compared with soil application of carbofuran 3G @ 1.3 g a. i./m² and an untreated control for the management of the nematode. Application of the biocontrol agent as seed treatment at a dosage of 10 g/kg of seed was superior to all the treatments. Maximum bacterial colonization and nematode suppression was observed in plants treated with P. fluorescens as seed treatment and it increased yield by 13 per cent.

Keywords

Heterodera spp., Hirschmanniella gracilis, Meloidogyne incognita, Rice.

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S. Ramakrishnan ¹, S. S. Sreenivas ¹

Affiliations
1 ICAR-CTRI Research Station, Hunsur-571105, Karnataka, IN

Abstract

Farm yard manure fortified with bio-agents Pseudomonas fluorescens, Trichoderma asperellum and Aspergillus niger either singly or in rational combinations were evaluated against soil- borne fungal pathogens in FCV tobacco nursery. Results of the trial indicated that, application of P. fluorescens and A. niger fortified FYM @ 4 kg/ m2 recorded 40.2 per cent increase in number healthy transplants (640/ m2) and was on par with recommended chemical schedule (627.5/ m2). At 60 DAS, P.fluorescens + A. niger fortified FYM, P. fluorescens + T. viride fortified FYM and chemical check were on par with each other in recording reduced RKI of 1.97, 2.08 and 1.91 respectively compared to 3.80 as RKI in untreated check. Similarly, Bio-agents fortified FYM recorded significant decrease in damping off at 35 DAS (41.1 to 52.4%), damping off + blight at 45 DAS (44.1 to 52.9%) and black shank (45.7 to 58.3 %) compared to untreated check. Though, the chemical schedule was superior in decreasing the damping off by 90.0%, damping off + blight by 93.9% and black shank by 93.4% compared to untreated check the study infers the effectiveness of bio-agents for reducing the chemical use to minimize environmental pollution.

Keywords

Aspergillus niger, FCV Tobacco, Nursery, Pseudomonas fluorescens, Soil-Borne Fungal Diseases, Trichoderma viride.

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