Resurgence of the brown planthopper, Nilaparvata lugens (Stål) on rice was induced by applications of decamethrin, methyl parathion, and diazinon. Differential mortality of predators and hoppers did not appear to be the primary factor for resurgence. Hoppers appeared to be attracted to methyl parathion and decamethrin treated plants because of plant growth. Improved plant growth, however, did not compensate for the increased feeding of the insecticide-treated hopper population, and plants treated with resurgence-causing insecticides succumbed to feeding injury earlier than untreated plants. Population increases were due in part to stimulation of reproduction of the hopper, either by contact action of the insecticides or through increased plant growth. Reduction in the length of the nymphal stage and increased adult longevity resulting in a shortened life cycle and longer oviposition period, respectively, were additional factors contributing to resurgence.

This paper is a position statement on reproducible research in linguistics, including data citation and attribution, that represents the collective views of some 41 colleagues. Reproducibility can play a key role in increasing verification and accountability in linguistic research, and is a hallmark of social science research that is currently under-represented in our field. We believe that we need to take time as a discipline to clearly articulate our expectations for how linguistic data are managed, cited, and maintained for long-term access.

Resurgence of Nilaparvata lugens (Stål) after insecticide application is a common phenomenon in rice in South and Southeast Asia. Among other insecticides inducing resurgence, carbofuran, decamethrin, and methyl parathion were selected for this study. Of the various methods of carbofuran application tested, foliar sprays were most active in inducing resurgence. Extent of resurgence was highly influenced by time of insecticide application. Sprays of methyl parathion and decamethrin applied 50 and 65 days after transplanting (DT) induced resurgence in the third generation of N. lugens at ca. 90 DT, whereas earlier applications had little effect. The cause(s) for resurgence was not definitely established, but stimulation of N. lugens reproduction appeared to be of more significance than destruction of natural enemies. In the last decade, Nilaparvata lugens (Stål) has risen from the status of a minor pest to a position of major importance in tropical Asia. This pest feeds at the base of the rice plant near the water level, causing direct damage which results in "hopperburn" and the transmission of grassy, ragged (Ling et al. 1978), and wilted stunt viruses (Chen et al. 1978). From 1972 to 1974, major N. lugens outbreaks occurred throughout South and Southeast Asia. The economic threshold is about one N. lugens per tiller or 20 per hill (Dyck and Orlido 1977), but under severe infestations the population may reach 50 times the threshold level.

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