%0 Article
%T Lygus bugs as agents of growth disorders in permethrin-treated pine seedlings in regeneration areas.
%A Kytö, Maarit
%D 1992
%J Silva Fennica
%V 26
%N 4
%R doi:10.14214/sf.a15648
%U https://silvafennica.fi/article/5487
%X <p>The ability of <em>Lygus</em> bugs to cause growth disorders in permethrin-treated Scots pine (<em>Pinus sylvestris</em> L.) seedlings after planting was studied in two regeneration areas. There were three treatments: exposure of the seedlings to <em>Lygus</em>, mechanical protection of the seedlings from insects, and control seedlings. There were no significant differences in the rate of growth disorders between the treatments. The permethrin application protected the seedlings against <em>Lygus</em> bugs in the early summer, as well as when the bug abundance was low. The development of these seedlings, as well as the multiple-leadered and bushy seedlings on a third regeneration area, was followed for two years. Multiple leaders reduced height growth and bud number of a seedling, but caused marked losses in growth only when the seedlings still had multiple leaders the following year, or when they formed several, equally developed stems. <br>The PDF includes an abstract in Finnish.</p>