Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Development of sampling designs for egg and larval populations of the wheat midge, Sitodiplosis mosellana (GĂ©hin) (Diptera: Cecidomyiidae), in wheat.

Abstract

The distribution of eggs and larvae of Sitodiplosis mosellana on wheat was investigated in north-eastern Saskatchewan in July and August 1984 and 1985. The highest number of each stage occurred in the top third of the head and the lowest number in the bottom third. The entire wheat head was considered an adequate sampling unit for density estimates of these 2 life stages. Sample sizes required to estimate egg and larval populations with given levels of precision were determined. A sequential sampling plan for larval populations was derived using Green's and Iwao's methods. Both methods gave similar results, but more samples were required with the former.