Effect of Bio-active Metabolites Secreted by Penicillium crustosum on the Germination and Early Seedling Growth of Parthenium hysterophorus

Abstract

Parthenium hysterophorus, commonly known as Congress grass or Gajar Ghas, is an invasive weed that poses a significant threat to agricultural productivity, livestock health, and native biodiversity. The present study evaluates the herbicidal potential of secondary metabolites secreted by the fungus Penicillium crustosum. The research utilized various concentrations (25%, 50%, 75%, and 100%) of the cell-free culture filtrate (CF) of P. crustosum to observe its impact on the seed germination and early seedling growth of Parthenium. Results indicated a dose-dependent inhibitory effect, where 100% concentration of the filtrate resulted in complete (100%) germination failure. Furthermore, lower concentrations significantly reduced radical and plumule length and induced chlorosis in emerging seedlings. Biochemical analysis suggests that mycotoxins such as Penitrem-A and Roquefortine C, along with various organic acids, are the primary agents responsible for this phytotoxicity. This study concludes that the secretions of P. crustosum hold substantial promise as a natural, bio-based alternative to synthetic herbicides for managing Parthenium infestations.