A simple, light clip-cage for experiments with aphids

1 Clip-cages are a useful experimental tool for confining small insects to leaves when aiming to study their behaviour and/or other biological parameters. Nonetheless, clip-cages are usually heavy and may damage the leaves, which renders them less useful for numerous research studies. We propose a very simple clip-cage, which is cheap, extremely light, and easy to make and handle, and which has less of the negative, damaging nature of traditional clip-cages. 2 Each clip-cage was prepared using two discs of foam-floating tubes: one for support and one for confining the insects. On the upper surface of the latter, a rectangle of microperforated plastic flower sleeve (8cm(2)) was glued using a nontoxic glue stick. To bind the two parts to the leaf, four staples (23/13) were used. We tested the clip-cages by confining Myzus persicae to Brassica oleracea and Brassica rapa leaves and then compared the results obtained with those acquired using classic clip-cages. 3 Each foam clip-cage was assembled in less than 2 min. Our experiments confirmed the M. persicae escape rate of 6%, which compared favourably with the escape rate of 40% for the classic clip-cage. Furthermore, the clip-cages did not interfere with the growth rate of the aphids. 4 The foam clip-cages are up to 200% cheaper than the classic clip-cages. They are light, durable, easily put together and transported, and have the potential to be easily used in field experiments.