Biological suppression of early blight disease (Alternaria solani Sorauer) in potato (Solanum tuberosum L.) using Bacillus subtilis (Ehrenberg) Cohn, Trichoderma harzianum Rifai and Nano Silica

2026-05-19T12:41:47+00:00

Background: Early blight disease, incited by the soilborne necrotrophic fungus Alternaria solani Sorauer, constitutes a major biotic constraint on potato (Solanum tuberosum L.) cultivation, with potential yield losses exceeding 86%. Repeated application of broad-spectrum synthetic fungicides has raised growing concerns regarding environmental contamination, pathogen resistance development, and agrochemical residues in food commodities.

Methods: A screenhouse experiment was carried out from January to May 2024 at the UPTD Seed Potato Station, Pangalengan, West Java, Indonesia (1,500 m a.s.l.; 18–25 °C). A Randomized Block Design was employed with seven treatments and four replications (28 plots; 12 plants per plot; cv. Granola L.). Treatments comprised: P1 – B. subtilis (10 ml/L; 10⁹ CFU/ml); P2 – B. subtilis + Nano Silica (3,000 ppm); P3 – T. harzianum (20 g/L; 10⁶ spores/ml); P4 – T. harzianum + Nano Silica; P5 – B. subtilis + T. harzianum + Nano Silica; P6 – untreated negative control; P7 – Mancozeb 80 WP (2 g/L). Applications began at 10 weeks after planting (WAP) and were repeated weekly for four consecutive weeks. Disease intensity was assessed using a 0–5 ordinal scale and converted to a disease index percentage. Data were subjected to ANOVA and mean separation by Duncan's Multiple Range Test (DMRT) at the 5% level.

Results: Treatment effects on disease intensity were highly significant at all post-application observation periods (F = 15.82–194.85; p < 0.001; R² = 0.82–0.98). At 13 WAP, the triple combination P5 (5.60%) was statistically equivalent to the Mancozeb standard P7 (5.72%), both being significantly superior to all other treatments, while the negative control P6 reached 23.56%. Tuber yield in P2 (636 g/plot) significantly exceeded P6 (375 g/plot). Plant height was not significantly affected by any treatment.

Conclusion: The combined application of B. subtilis, T. harzianum, and Nano Silica (P5) effectively suppressed A. solani to a level statistically equivalent to the synthetic fungicide standard, representing a viable eco-friendly alternative for integrated early blight management in potato production.

Roost tree ecology and habitat use in shergarh wildlife sanctuary, Kota, Rajasthan

2026-05-21T11:08:40+00:00

A field-based assessment of roost trees was conducted across Barapati, Chota Dungar, Tikli, Amlawda, and Bada Dungar forest blocks of Shergarh Wildlife Sanctuary. A total of 281 roost-tree observations belonging to 56 tree/shrub species were documented. Structural parameters including GBH and height were analyzed along with roosting associations of birds and mammals. IVI analysis identified dominant ecological roost species, while Shannon and Simpson diversity indices revealed high habitat heterogeneity across forest blocks. Statistical analysis indicated significant variation in GBH among blocks (ANOVA F=0.19, p=0.9449). Large canopy species such as Terminalia bellirica, Mitragyna parvifolia, Ficus benghalensis, and Anogeissus pendula emerged as keystone roost trees supporting raptors, owls, hornbills, parakeets, and passerines.

International Journal of Phytology Research

Biological suppression of early blight disease (Alternaria solani Sorauer) in potato (Solanum tuberosum L.) using Bacillus subtilis (Ehrenberg) Cohn, Trichoderma harzianum Rifai and Nano Silica

Roost tree ecology and habitat use in shergarh wildlife sanctuary, Kota, Rajasthan