Growers in Ontario continue to struggle with Thrips parvispinus on tropical crops like mandevilla, anthurium and schefflera. Unfortunately, reports out of Europe also indicate this invasive pest species can also attack poinsettia.
The Issue
Although poinsettia (Euphorbiae pulcherrima) have not previously been reported as a host plant for Thrips parvipsinus (see https://mrec.ifas.ufl.edu/lsolab/thrips/thrips-parvispinus/ for all reported hosts), a grower in Europe was kind enough to reach out to me and send pictures of the damage he’s seen in this crop. Thrips parvispinus was confirmed as the culprit by local entomologists.
The damage looks much like “regular” thrips damage from western flower thrips or Echinothrips (see this photo from U Mass extension.) However, as seen with T. parvspinus feeding damage on other crops, there is also lots of tissue distortion on new leaves.
Thrips parvispinus has been found in many countries at this point (see Fig. 3) and can likely be found in adjacent countries as well, even if it hasn’t been formally detected yet. Many of these countries supply poinsettia cuttings around the world. These include Spain, Guatemala and EL Salavador, as well as Kenya and Ethiopia (which are right next to Tanzania and Uganda, where T. parvispinus has been found).
Read more at onfloriculture.com