Strategie di lotta contro le virosi del ranuncolo in Liguria.

Due to the increasing damage caused by virus infections to Ranunculus sp. crops in the Italian Riviera, research work on viruses and disease control experiments in both protected and filed crops were conducted. Different potyviruses were identified as the most important etiological agents, and studies on their aphid vectors showed that they accomplish consistent flight movements from September to December, with pronounced picks in October and November. This temporal period was thus identified as the most important for the spreading of virus in crops and then the one requiring the most careful control means. Experiments to control virus spreading were carried out by removing manually early infected plants in crops (infection foci) and by using white plastic nets of the shadowing type as both physical and chromatic 'barriers' to keep aphids out of crops. Both such techniques, when employed properly, as described in the many cases reported, supplied satisfactory results and were also relatively cheap, easy to practice and fully ecological.