L. FURLAN, S. ZANGHERI
Department of Agronomy, Entomology, University of Padova, Agripolis-Via Romea 16-35020 Legnaro PD, Italy
S. BARBIERI
Veneto Agricoltura, Corte Benedettina, via Roma 34, Legnaro PD
S. LESSI, I. DELILLO
A.R.P.A.V., Meteorological Center of Teolo: via Marconi 55, 35037 Padova
F. TOFFANIN
Coldiretti, Venezia
F. BRICHESE
Regione Veneto

Agrotis ipsilon (black cutworm) has caused severe damage to maize and other crops (thousands of hectares were destroyed) in some years; in Italy particularly in 1971, 1983 and 1994.  Anyway almost in each year local outbreaks can cause reductions of corn stand or even the need of replanting. Usually the farmers realize the extent of the damage too late and rescue treatments become ineffective. Therefore a black cutworm alert programme that can inform the farmers about the presence of black cutworm economic populations in time has been tested in Veneto region.

MATERIALS AND METHODS
The procedure suggested by Iowa University and Extension Service has been implemented in Veneto region since 1991. Sex pheromone traps (Hartstack baited with lures prepared by INRA and Plant Protection Institute of Budapest) were placed out in maize fields of Veneto provinces since late February of each year. Air and soil temperatures, information about direction and strength of the winds were supplied by A.R.P.A.V. Degree days (development zero = 10.4 °C) were calculated since the first conspicuous captures recorded by the traps just after strong winds coming from Southern regions. Tens of maize fields, in the area where males had been captured, were investigated every 2 days from late April of each year to observe in open field when really the 4^th instar larvae started damaging the small maize plants.
RESULTS
Moth captures greatly varied between different years. No or very low numbers of moths were observed in years when no or weak Southern winds occurred; in these years no conspicuous black cutworm damage on maize plants was observed. In other years the first captures were recorded 1-2 days after strong Southern winds had occurred. The alert programme gave reliable results by using soil surface temperatures in calculating Degree Days accumulation, while the use of air temperatures underestimated the DDA. The first fourth instars larvae were observed 2-4 days before the date forecast by the model (176 DDA for 50% of 4^th instars larvae in the population); it was possible forecast the period of maximum larval presence with an error of plus or minus 1-2 days making effective the rescue treatments where threshold had been overcome. Information was sprayed through the specific bulletin issued by A.R.P.A.V., Internet, newspapers and television channels.