Description, Biology, Life Cycle, Damage, Common Names, Images
Host plants include mainly cereals, especially winter rye, spring wheat and barley.
- Nymphal development lasts 3-5 weeks or more according to temperature.
- Apterous males mate with 'pre-pupae' (females).
- There are 2 generations per year.
- These insects overwinter in the adult stage, in tufts of grass along the edge of paths, moss, at the edge of fields, in litter, bark and under stones.
- In the spring (April) colonies develop in cereal fields and egg-laying takes place in the plant tissues.
The 2 active nymphal stages are followed by a 'pre-pupal' stage and 1 or 2 semi-active 'pupal' stages. Nymphs feed on the tissues of leaf sheaths and stems.
- A mild and dry spring climate favours breeding, the most numerous colonies developing after ear emergence and the growth of cereal panicles.
- In September, adults seek for a shelter in which to overwinter in, even sometimes as early as July when there is a drought and thus a lack of host plants such as wild Gramineae.
- Damage is caused to the epidermis of plants, cells having been punctured. The epidermis takes on a silvery-white coloration before turning yellow and brown.
Dark spots of excrement (frass) appear on affected parts of plants.
- Because of the punctures made in glumes, ovaries and ovules, grains form imperfectly.
- Yields are reduced by 15% and sometimes even more.
HYPPZ on line : Species (scientific name), Pests (common names), Glossary, Crops.