Open Access Library Journal 2021, Volume 8, e7219 ISSN Online: 2333-9721 ISSN Print: 2333-9705 DOI: 10.4236/oalib.1107219 Mar. 31, 2021 1 Open Access Library Journal Pathological Survey on Early Leaf Blight of Tomato and In Vitro Effect of Culture Media, Temperature and pH on Growth and Sporulation of Alternaria solani I. Parvin 1 , C. Mondal 1 , S. Sultana 1 , N. Sultana 2 , F. M. Aminuzzaman 3* 1 Agrotechnology Discipline, Khulna University, Khulna, Bangladesh 2 Department of Plant Pathology, Bangladesh Agricultural University, Mymensingh, Bangladesh 3 Department of Plant Pathology, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka, Bangladesh Abstract Alternaria solani causing early blight of tomato is a serious disease, causing 50% to 86% losses in fruit yield and 20% to 40% losses in seedling establish- ment. Pathological survey, etiology and physiological characterization of the causal organism are necessary to formulate effective management strategy. Therefore, present study was conducted to determine the incidence and se- verity of early leaf blight of tomato in some selected area of Bangladesh and to evaluate the effect of different culture media on radial mycelial growth and sporulation as well as the effect of pH and temperature on mycelial growth. Survey was conducted in five upazilas of Bogura district and typical early blight disease sample was collected from surveyed field and Germplasm Cen- tre, Agrotechnology Discipline, Khulna University, Khulna. Seven different culture media were used namely Potato Dextrose Agar (PDA), Richard’s Agar (RA), Waskman Agar (WA), Corn meal Agar (CA), Asthana and Hawker’s Agar (AHA), Oat Meal Agar (OMA), V-8 Juice Agar Medium (VJAM) and seven different pH level such as 5.0, 5.5, 6.0, 6.5, 7.0, 7.5 and 8.0 were used and also exercised five distinct temperatures such as 20˚C, 25˚C, 30˚C, 35˚C and 40˚C to appraise cultural characters, mycelial growth and sporulation of A. solani. Cultural characters such as colony color, colony diameter, growth margin, growth surface and margin topography showed distinguished varia- tion in culture media. Among the seven different media V-8 Juice Agar Me- dium gave not only maximum mycelial growth (73.10 mm) but also highest sporulation (2000 spores ml −1 ). The optimum pH for maximum mycelial How to cite this paper: Parvin, I., Mondal, C., Sultana, S., Sultana, N. and Aminuzza- man, F.M. (2021) Pathological Survey on Early Leaf Blight of Tomato and In Vitro Effect of Culture Media, Temperature and pH on Growth and Sporulation of Alternaria solani. Open Access Library Journal, 8: e7219. https://doi.org/10.4236/oalib.1107219 Received: February 9, 2021 Accepted: March 28, 2021 Published: March 31, 2021 Copyright © 2021 by author(s) and Open Access Library Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access