19th Century

In the second half of the 19th Century, the vine was attacked by pests and diseases responsible for a reduction in wine production.

By 1851, the vines were attacked by powdery mildew, a disease characterised by a white powder on the berries, which ends up making them fall. This represented significant reductions in production. It was later discovered that this disease could be fought spraying the grapevines with sulphur.
1853 was the year downy mildew attacked the vines. Luckily, the treatment for this disease had already been discovered (to cover the vines with copper sulphate and lime), so consequences in Portugal were not very serious.

Phylloxera entered Portugal through the Douro region, in 1867, and quickly devastated vines all over the country. This insect attacks the grapevine’s root to feed from its juice, resulting in the death of the plant. Colares was the only region to escape from this pest, since the phylloxera insect doesn’t develop on sandy soils. When it was found that American grapevines were resistant to this disease, European vines started to be grafted with American roots, in order to prevent the pest. This is still done today.

In 1866 a commission was created to evaluate wine regions and their response to diseases. This commission was formed by António Augusto de Aguiar, João Inácio Ferreira Lapa and the Viscount of Vila Maior.

In 1874, António Augusto de Aguiar was nominated Royal Commissioner at the London Wine Exhibition. He then travelled through other European countries where he gained the necessary experience to evaluate the Portuguese wine sector. In 1875, António Augusto de Aguiar was responsible for the Conferências sobre Vinhos (free translation: Conferences on Wine), at the D.Maria and Trindade Theatres.