Seven agricultural gels were tested as potential carriers for the eggs
of 2 predators, Perillus bioculatus (F.) and Podisus maculiventris (S
ay) (Heteroptera: Pentatomidae). Gels were tested for their effects on
egg hatch in petri dishes, covered and uncovered, using 3 viscosities
. Egg hatch in petri dishes was generally higher in polyacrylamide gel
s (Aquastore F and Terra-sort GB) and starch-based gels (SGP 104K and
Waterlock B-100) than in hydroxycellulose-based N-Gel or alginate-base
d Keltose. Egg hatch was lower in covered versus uncovered dishes, and
also lower in high viscosity versus low or medium viscosity gels; how
ever, high viscosities were necessary to stick eggs to plant leaves. F
our gels from the petri dish trials were tested on eggplant (Solanum m
elongena L.) and potato plants (Solanum tuberosum L.) in the greenhous
e using both predators. The polyacrylamide gels (Aquastore F and Terra
-sorb GB) consistently resulted in the highest percentage hatch: hatch
rates using these gels were equivalent to the control for P. maculive
ntris on eggplant, and 19 -46% lower than controls on other predator-p
lant combinations. Hatch data from eggs stored with and without Aquast
ore F or Terra-sorb GB at 5, 10, or 15 degrees C for 5, 10, or 15 d we
re compared with those stored at 25 degrees C, with and without gel. E
ggs stored in gel did not hatch. Percentage hatch of eggs of both pred
ators stored without gel was lowered by increased storage duration, bu
t was less affected by temperature. Gel amendments (H2O2 and spreader/
stickers) decreased hatch rates in gels. Possible explanations for the
varying effects of the gels on egg hatch are discussed. Delivery of p
redator eggs in gels in the future may have practical use in augmentat
ive biological control programs.