Background
The authors write that "the grape leafhopper Empoasca vitis is regarded as a major insect pest in many European grapevine growing areas, with an increasing importance realized in recent years, maybe as a result of climatic change."

What was done
In an experiment designed to explore the latter hypothesis, Reineke and Hauck studied the development of larval instars of two leafhopper species, E. vitis and E. rosae on grapevine leaves under different temperature regimes in the laboratory.

What was learned
The two German researchers report that the shortest larval developmental time they observed occurred at night temperatures of 13-15°C and day temperatures of 23-25°C, which they say "was in agreement with predicted optimal temperatures for both species." In addition, they write that "at the temperature regime of 20°C night and 30°C day temperature, either no egg hatch was observed or early development of first-instar larvae was not successful for both species."

What it means
Repeating the final sentence of the abstract of Reineke and Hauck's paper, "these results suggest that warm (18°C) nights and moderately warm (28°C) days are representing the upper thermal threshold for development of both E. vitis and E. rosae embryonic stages on grapevine leaves, questioning current assumptions of an increasing importance of E. vitis as a grapevine pest under future climate change."