S. Manju ¹, P. M. M. David ¹

Affiliations
1 Department of Agricultural Entomology, Agricultural College and Research Institute, Killikulam, Vallanad 628252, Tamil Nadu, IN

Abstract

Field experiments were conducted to study the effects of soil and foliar application of certain neem products on the densities of egg masses of the yellow stem borer, Scirpophaga incertulas(Walker) (Lepidoptera: Pyralidae), and on the extent of egg parasitism due to Telenomus dignus (Gahan) and Tetrastichus schoenobii(Ferreira). NPK fertilizers and organophosphate insecticides were included for comparison. The egg mass numbers and their parasitism were assessed at fortnightly interval. The results indicated that the egg masses were more numerous in NPK plots (2.16/m²) than in neem cake plots (1.10/m²), while the parasitism was higher on plants sprayed with neem products+fish oil rosin soap (26.28%) in neem cake plots than on plants with no plant protection in NPK plots (20.92%).

Keywords

Egg Masses, Egg Parasitism, Neem Products, Rice YSB.

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B. Gajendra Babu ¹, P. M. M. David ¹

Affiliations
1 Department of Agricultural Entomology, Agricultural College and Research Institute (TNAU), Killikulam, Vallanad 628 252, Tamil Nadu, IN

Abstract

A simple roping technique that facilitates rapid multiplication of mealybugs even on smooth pumpkins (Cucurbita moschata Poir) devoid of ridges and furrows is described. After 20-40 days of ovisac inoculation, populations of Maconellicoccus hirsutus (Green) were 8-12 times significantly higher on grooveless pumpkins secured vertically across with 4 mm thick ropes at 2-4cm interspacing at the widest girth than that on bare grooveless pumpkins. However, populations increased by only 2-3 times on deep-grooved pumpkins and by 4-5 times on shallow-grooved fruits. Mealybugs were significantly more along 4mm thicker top rope than along 2mm thinner twine running vertically across the fruit surface.

Keywords

Biocontrol, Grooveless Pumpkin, Mealybug Culture, Technique.

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V. Venkadasubramanian ¹, P. M. M. David ¹

Affiliations
1 Department of Agricultural Entomology, Agricultural College and Research Institute, Killikulam, Vallanad 628 252, Tamil Nadu, IN

Abstract

Bioefficacy of commercial Bacillus thuringiensis (B.t.) products namely Delfin (B.t.var.kurstaki), Spicturin (B.t.var.galleriae) and Agree (B.t.var. kurstaki+aizawai) (each at 0.1%) in combination with botanicals viz., neem (Azadirachta indica A. Juss) seed oil (1.5%), mint (Mentha spicata L.) leaf extract (2.5%), sweet flag (Acorus calamus L.) rhizome extract (0.5% ), bracteated birthwort (Aristolochia bracteata Retz.) leaf extract (2.5%), mesquite (Prosopis juliflora DC.) leaf extract (2.5%), Indian aloe (Aloe vira L.) leaf extract (0.5%) and palmarosa plant (Cymbopogan martini Wats.) oil (0.5%) was tested in laboratory against tobacco cutworm, Spodoptera litura (Fabricius) and gram pod borer, Helicoverpa armigera (Hubner). Toxic effects of B.t. products and palmarosa oil in mixture were significantly superior to that of other combinations.

Keywords

Bacillus thuringiensis, Botanicals, Helicoverpa armigera, Spodoptera litura.

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J. Loganathan ¹, P. M. M. David ²

Affiliations
1 E.I.D. Parry (India) Ltd., Agritech Research Centre, 145 Devanahalli Road, Bangalore 560 049, IN
2 Department of Agricultural Entomology, Agricultural College and Research Institute (TNAU), Killikulam, Vallanad 628 252, Tamil Nadu, IN

Abstract

Parasitism in teak defoliator, Hyblaea puera Cramer (Lepidoptera: Hyblaeidae) was studied in an intensively managed teak plantation at Veeravanallur, South Tamil Nadu. Among the recorded parasitoids namely, Sympiesis sp. (Hymenoptera: Eulophidae), Sarcophaga sp. (Diptera: Sarcophagidae) and Palexorista solennis Walker (Diptera: Tachinidae), the latter was most predominant. Parasitism by P. solennis ranged from 8.0 per cent in October when defoliator was in the first generation to a peak of 54.54 per cent in December, suppressing the defoliator larval population in the fourth generation.

Keywords

Hyblaea puera, Intensively Managed Teak Plantation, Natural Parasitism.

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V. Venkadasubramanian ¹, A. Janagarajan ¹, P. M. M. David ¹

Affiliations
1 Department of Agricultural Entomology, Agricultural College and Research Institute, Killikulam 628 252, Tamil Nadu, IN

Abstract

The influence of Electrical Conductivity (EC) - based quality of water, used as spray fluid, on the bioefficacy of commercial formulations of Bacillus thuringiensis (Berliner) (B.t.) was studied in laboratory bioassays against Spodoptera litura (Fabricius) and Helicoverpa armigera (Hiibner). EC quality did not alter the efficacy of B. t. formulations significantly. However, larval mortality decreased with increase in EC.

Keywords

Bacillus thuringiensis, Bioefficacy, Helicoverpa armigera, Spodoptera litura, Water Quality.

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