Find in Library

Excessive zinc (Zn) is toxic to plants, but the effect of zinc-stressed plants on herbivorous insects is still unclear. Hence, we assessed the effect of zinc-stressed rice plants on its feeding pest, <i>Nilaparvata lugens</i>. The soil–rice–<i>N. lugens</i> system was treated with Zn²⁺ solution. Sugar content in rice was measured, and the reproduction and trehalose metabolism in <i>N. lugens</i> were assessed. The trehalase activity in rice significantly decreased at 100 mg·kg⁻¹ Zn²⁺, and the trehalose content increased. The glucose and starch content increased at higher Zn²⁺ concentrations. The fecundity and trehalose content of <i>N. lugens</i> decreased after feeding on zinc-stressed rice, and the glucose content in the high Zn²⁺ group was significantly higher than that in the low Zn²⁺ group. In addition, the soluble trehalase activity of <i>N. lugens</i> significantly decreased under the 125 mg·kg⁻¹ treatment, while the activity of membrane-bound trehalase significantly increased under the 150 mg·kg⁻¹ treatment. Quantitative RT-PCR indicated significantly lower expressions of <i>NlTre1-1</i>, <i>NlTre2</i>, and <i>NITps</i> after Zn treatment. In conclusion, Zn²⁺ treatment significantly altered the sugar content in rice plants; it also decreased the fecundity of <i>N. lugens</i>, which may be mediated by alterations in trehalose metabolism.