Mealworm frass as a potential biofertilizer and abiotic stress tolerance-inductor in plants

13 páginas, 3 tablas y 5 figuras

Frass from the insect Tenebrio molitorcan be applied as an organic fertilizer due to its nutritional content. In this study insects were fed on different types of foodproducing excrement with different compositions. This allowed us to compare the potential effect of the excrement on plant growth promotion and to test its ability to increase tolerance to abiotic stresses such as drought, excess water and salinity. The best results were obtained when the insects were fed a diet low in fat andstarch content. Moreover, a microbiological study using the excrement produced showed that the presence of microorganisms improved plant growth parameters, inthe absence or presence of stress conditions. The analysis of the microbiome through massive parallel sequencing, as well as the analysis of the capacity of severalmicrobial isolates to promote plant growth, showed that several microorganisms present in the excrement are plant growth promoters (PGPs). Ourfindings indicatethat the frass produced by these insects, due to its nutritional content and associated microbiota, can be potentially used as a biofertilizer in organic farming.However, this potential dramatically varies according to the insect's diet. Further analyses should be performed to set the optimal time and amount of application forthe different aimed plant

The Spanish Ministry of Economy and Competitiveness (MINECO) grant PTQ-14-07381 provided the financial support to co-fund the workcarried out by PGF, JPA was co-funded by grant DI-15-07460 and ZSSwas funded by a grant from“Junta de Castilla y Leon (JCYL)”

Peer reviewed