Effect of seed treatment with coelomic fluid secreted by Perionyx excavatus on corn seedling and control of Aspergillus flavus

Abstract

Importance of the work: Aspergillus flavus contamination could lower corn seed quality and aflatoxin production. Depending on the concentration, certain chemicals used for fungal control are harmful to the environment; consequently, natural products are increasingly used as alternatives. Coelomic fluid secreted by the blue worm, Perionyx excavatus, has been found to affect plant growth and to inhibit growth of Aspergillus species.Objectives: This work investigated the appropriate coelomic fluid concentration to promote corn seedling and inhibit the growth of A. flavus. Materials & Methods: Corn seeds were treated with 0%, 1%, 2.5%, 5%, 10%, 15%, 20% or 30% coelomic fluid solution. Results: The seeds treated with coelomic fluid solutions had higher shoot lengths (p < 0.01) than the control but there were no significant differences between the concentrations. Mean (± SD) shoot lengths of seeds treated with 0% and 1% coelomic fluid solution were 19.07 ± 0.89 cm and 23.14 ± 1.32 cm, respectively. In the second experiment, corn seeds were contaminated with A. flavus and subsequently soaked in 100% coelomic fluid or fungicide solution and compared with non-contaminated seeds and non-treated seeds. The results indicated that the coelomic fluid had the greatest inhibition on the growth of A. flavus. The level of fungal infection of coelomic fluid solution treatment was 0%, while the mean (± SD) infection levels for the fungicide treatment and non-treated seed were 1.67 ± 1.92% and 27.5 ± 11.34%, respectively. Main finding: This study revealed that coelomic fluid secreted by P. excavatus significantly enhanced seedling growth and inhibited the growth of A. flavus.