Induction of defense responses in longkong fruit (Aglaia dookkoo Griff.) against fruit rot fungi by Metarhizium guizhouense

Publication date: Available online 27 May 2017 Source:Biological Control Author(s): Thanunchanok Chairin, Vasun Petcharat The defense responses of longkong fruit were induced by an entomopathogenic fungus, Metarhizium guizhouense. The longkong fruits were dipped in a spore suspension of M. guizhouense PSUM04 at concentration of 104 spore mL -1 for 5 sec, then an enzyme assay, a protein assay and Polyacrylamide Gel Electrophoresis (PAGE) were done. It was found that the longkong fruit presented small necrotic spots on their peels within 24 hours. β-1,3-glucanase and chitinase were detected in peel extracts at 1.33 ± 0.09 and 0.12 ± 0.004 U mL -1, respectively. The sodium dodecyl sulphate (SDS)-PAGE showed protein bands that emerged after the fungal treatment when compared to untreated control. These proteins were a 25-27 kDa group of chitinase isoforms, and β-1,3-glucanase at 43 kDa. From gel diffusion method, crude extracted from the fruit peel inhibited the mycelial growth of Botrytis sp. and Fusarium sp. as 34.9 ± 3.1 and 29.3 ± 5.0%, respectively. Moreover, the observation from Scanning electron microscope (SEM) showed abnormal shapes, twisting and cracking in both fungal mycelia and less dense mycelial growth for Fusarium sp. Thus, M. guizhouense PSUM04 was not only a bio insecticide but it was also be the biotic inducer of plant defense responses against pathogenic fungi.

Source: Biological Control - May 28, 2017 Category: Biology Source Type: research