Survival of Steinernema feltiae in different formulation substrates: Improved longevity in a mixture of gel and vermiculite

This study assessed the performance of seven different formulation substrates and two combinations involving vermiculite and gel, to preserve Steinernema feltiae at three temperatures: 15 °C, 25 °C and 35 °C. The first two experiments assessed the survival and mobility of S. feltiae infective juveniles (IJs) in mushroom compost (Hobin Wood Landscaping Products), peat (sphagnum peat moss), Potting mix (Metro Mix®), polyacrylamide gel, diatomaceous earth, vermiculite, and water (control). A third experiment assessed the survival of IJs in combinations of the two best substrates selected from the prior tests: vermiculite, polyacrylamide gel (1.33%), double polyacrylamide gel (2.66%), vermiculite + gel (1.33%), vermiculite + double gel (2.66%), and water (control). The greatest IJ fitness at 35 °C and 25 °C was observed in peat and vermiculite, respectively, and at 15 °C the gel and water treatments were superior. In general, vermiculite and polyacrylamide gel were the two best substrates considering that they provided the best results at 25 °C and 15 °C. The polyacrylamide gel formulation held higher numbers of nematodes in the substrate compared with the solid substrates. The mixture of vermiculite + double polyacrylamide gel provided the best preservation at 35 °C compared to the substrates tested separately. The combination of vermiculite with polyacrylamide gel preserves S. feltiae IJs with viability higher than 80% for at least 30 d...

Source: Biological Control - July 5, 2018 Category: Biology Source Type: research