Integrated Tactics for Managing the Mexican Rice Borer (Lepidoptera: Crambidae) in Sugarcane

Abstract

A 2-yr field study conducted in Texas to evaluate the effect of several management strategies on the Mexican rice borer, Eoreuma loftini (Dyar), in sugarcane, Saccharum spp. hybrids, showed that irrigation reduced injury in both susceptible (LCP 85–384) and resistant (HoCP 85–845) cultivars by 2.5-fold. Cultivar LCP 85–384 was more susceptible than HoCP 85–845 based both on injury and moth production. Irrigation, host plant resistance, and insecticide applications of tebufenozide decreased injury from 70% bored internodes to <10% during both years. The use of multiple control tactics was substantially better at suppressing E. loftini in sugarcane than solely relying on insecticide applications. In addition to accumulations of proline, several free amino acids (histidine and isoleucine) essential for insect growth and development were increased in sugarcane leaves by drought stressed conditions, which exacerbated E. loftini infestations. Modifying the suitability of the crop by reducing water deficit stress makes rational irrigation input a key component in the integrated pest management of E. loftini, in addition to other tactics such as cultivar resistance and insecticide application.