Evaluation of botanical extracts and biocontrol agents for the management of leaf spot disease in Aloe vera caused by Alternaria alternata

Abstract

Aloe vera, also known as Gheegwar or Ghritkumari, and scientifically known as Aloe barbadensis, belongs to the Aloeaceae family. During the period of 2013-2024, Aloe vera leaf spot disease was observed in "Crop cafeteria" of ITM University, Gwalior. The present study conducted an investigation on eco-friendly management of leaf spot disease of Aloe vera caused by Alternaria alternata. Five botanical extracts namely Neem, Moringa, Garlic, Akanda and Lantana were tested at three different concentrations viz. 5%, 10%, 15% with three replications each using poison food technique. The results revealed that out of all the five botanical extracts, Neem@15% exhibited the highest inhibition percentage of mycelial growth of A. alternata (49.59%) followed by Garlic@15% (47.43%). Five biocontrol agents namely Trichoderma spp., Trichoderma viride, Trichoderma harzianum, Pseudomonas fluorescens and Bacillus subtilis were used to study the antagonistic activity against A. alternata using dual culture technique. Among the five antagonists, Trichoderma viride (75.94%) exhibited the maximum inhibition percentage of the radial growth of A. alternata followed by Trichoderma sp. (75.47%) and T. harzianum (70.34%).