Potential Resistance in Zoysiagrasses to Tawny Mole Crickets (Orthoptera: Gryllotalpidae)

Reduction in growth by tawny mole crickets, Scapteriscus vicinus Scudder, at densities equivalent to 15 adults per 0.09 m2 varied among nine experimental and three commercially available zoysiagrass (Zoysia Willd.) cultivars. Reductions in root dry weights after a four week infestation period were similar among all cultivars, and averaged 27.1% less than non-infested controls. Shoot dry weight reduction was most severe for DALZ 8516, DALZ 9006, and Meyer zoysia. The cultivars that retained the highest percentage of their normal growth were DALZ 8502, DALZ 8514, DALZ 8701, and Emerald zoysia. Crickets fed on cultivars that were least damaged usually produced the least number of eggs. However, when the most severely injured selection (DALZ 8516) served as the host, a similarly low number of eggs was observed. Crickets fed on Meyer zoysia and DALZ 8508 produced the greatest number of eggs.