Science – Karlsruhe – Expert: Pests cannot be predicted yet – Knowledge

Karlsruhe (dpa/lsw) – With February looking partly like spring, the first insects, including pests, are already beginning to crawl and flee. However, according to Christine Dieckhoff, the forecasts for the current year and the potential damage to agriculture cannot be relied upon. She heads the Department of Biological Plant Protection at the Augustenburg Center for Agricultural Technology (LTZ) in Karlsruhe.

“Those who are awake now are more likely to burn energy than cause damage,” Dyckhoff said, citing stink bugs as an example, which overwinter in buildings. The animals were looking for food, but they did not find anything except greenhouses. Then wetter and cooler phases can come again in the spring, perhaps even with frost. “If you don't get to the bunker in time, you're out of luck,” the expert said. The other animals returned to a resting state.

She explained that short periods of warmth in general are not important for the spread and reproduction of pests. “This won't happen in a few days.” However, if the temperature increases over several years, it can certainly have an impact and affect population dynamics. Species such as the Japanese beetle, which has evolved over two years, may only need one species.

The profiteers of climate change are migrating – but their enemies are missing

There are many climate winners, Dieckhoff said, especially among so-called neozoa — that is, introduced animal species. “They benefit from rising temperatures.” The green rice bug, which comes from East Africa, was discovered in Germany more than 40 years ago. However, it only really spread in mid-2010. According to LTZ information, warmer areas such as those along the Rhine River from the Swiss border to North Rhine-Westphalia and the Central Neckar region are particularly affected.

Scientists in Karlsruhe are conducting research, among other things, on how to combat invasive species. The problem is that there are usually no natural enemies in this country. This means that agricultural pests, which make up only a small portion of all insect species, pass easily and can cause significant damage.

© dpa-infocom, dpa:240221-99-64542/2