Manufacturing of Granular Matrix with Diatomacious earth, Lime and Sugarcane Bagasse ash to Encapsulate Entomopathogenic Nematodes (Steinernema glaseri)

Abstract

An alternative for pest control in corn production is the use of biopesticides formulated with entomopathogenic nematodes encapsulated in granular matrices. However, it has been observed that the granular matrices´ lack of resistance to handling and transport causes their deterioration, therefore limiting their use. This study analyzes the use of lime and sugarcane bagasse ash as stabilizer additives in granular matrices made of diatomite earth in order to improve the survival rate of Entomopathogenic Nematodes. Six formulations were prepared and evaluated at 3, 12, 21 and 30 days of age. A total of 192 granular matrices were produced, 144 for axial compressive strength testing and 48 for the estimation of the survival rate of the nematodes. In order to carry out the last test, Steinernema glaseri nematodes were encapsulated. The results indicate that the granular matrices made with the combination of 88% diatomaceous earth plus 6% lime and 6% sugarcane bagasse ash have adequate hardness (mechanical strength) for handling and transportation purposes; in addition, at 30 days of age the survival rate was the highest obtained when compared to the granular matrices of all tested formulations