R. K. Srivastava ¹, R. K. Singh ¹, R. D. Prasad ²

Affiliations
1 Department of Plant Pathology, Crop Research Station, Bahraich, 271801, Uttar Pradesh, IN
2 Oilseeds Research, Rajendranagar, Hyderabad, 500030, Andhra Pradesh, IN

Abstract

Isolates of Trichoderma viride and T. harzianum were tested for their myco-parasitic ability and relative antagonistic effect that showed all the Trichoderma isolates inhibited significantly the growth of the pathogen and it ranged from 62.73% (T. viride 1) to 45.37% (T. viride PDBC TV 23). Germination per cent ranged from 78.8 (T. viride 3) to 98.9 (T. viride PDBC TV 23) when treated with bio-agents, whereas in pathogen check it was only 73.3%. Maximum vigor index (547.3) was recorded in T. viride (PDBC TV 23), whereas in pathogen check it was 84.7 only. Fungicide treatment exhibited almost equal disease incidence and in pathogen check, it was as high as 68.9%, while minimum (16.7%) plant mortality was recorded in seeds treated with T. viride 1. In fungicidal treatment 33% plant mortality was recorded while in pathogen check it was highest (46.7%). The results obtained clearly indicated that the efficacy of different isolates of the same species also showed variation when tested against the same pathogen. Therefore, it may be concluded that before application in the field the potentiality of every strain of the bioagents should be tested against the target pathogen.

Keywords

Antagonist, Trichoderma Spp, Phytophthora capsici, Bell Pepper.

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R. K. Srivastava ¹, R. K. Singh ¹, N. Kumar ¹, S. Singh ¹

Affiliations
1 N. D. University of Agriculture and Technology, Department of Plant Pathology, Crop Research Station, Bahraich 271801, Uttar Pradesh, IN

Abstract

An experiment was conducted in R.B.D. with seven treatments in four replications with olitorius jute variety JRO524 for five consecutive years (2002-07) at the experimental farm of the Crop Research Station, Bahraich in a plot size of 3X5 m² with a row spacing of 30 cm. Recommended doses of N:P:K @ 60:30:30 kg ha^-1 were applied. The treatment with soil application of Trichoderma viride thrice, i.e., 7, 15, 30 DAS was found best in controlling seedling blight, collor rot, stem rot and ischolar_main rot diseases giving minimum per cent disease incidence (1.45, 3.07, 4.70 and 4.92, respectively) as compared to control (16.12, 9.47, 16.67 and 16.34, respectively). Soil application with T. viride twice (7 and 15 DAS) showed 2.05, 4.42, 6.14 and 6.15% incidence of the same diseases and ranked second. The treatment with carbendazim 50WP @ 2g kg⁻¹, seed showed 8.52% seedling blight 5.24% collor rot, 6.93% stem rot and 8.56% ischolar_main rot incidence. Mean dry fibre yield was highest (25.70q ha⁻¹) in the plots when the soil was treated with T. viride at 7, 15 and 30 DAS, while it was lowest in control (17.76q ha⁻¹) and in carbendazim treatment it was 22.23q ha⁻¹. Variation in yield was due to the variations in plant height and basal diameter.

Keywords

Biological Management, Macrophomina phaseolina, Jute, Trichoderma viride.

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D. Rai ¹, R. Ujagir ¹, R. K. Singh ¹

Affiliations
1 Department of Entomology G.B. Pant University of Agriculture and Technology Pantnagar 263145, Uttaranchal, IN

Abstract

Extent of natural larval parasitization by Campoletis chlorideae on Helicoverpa armigera varied from 5 to 41 per cent during 1999-2000 and 3 to 40 per cent during 2000 2001 on standard week basis. Parasitization recorded during 1999 2000 was 33 per cent, 37.3 per cent and 9 per cent during February, March and April, respectively. During 2000-2001 it was 36 and 5 percent in March and April, respectively.

Keywords

Campoletis Chlorideae, Gram Pod Borer, Larval Parasitization.

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