Leopard moth larva on the mined trunk of a young pear tree.

Leopard moth larva on the mined trunk of a young pear tree.

With about 12,000 hectares (almost 30,000 acres) of pears and average annual production of about 130,000 metric tons, Portugal ranks last among the top 18 pear-producing countries worldwide. Nonetheless, pears make up about 12 percent of a very diversified fresh fruit industry, which includes a range of crops from citrus and figs to temperate deciduous fruits.

The pear industry of Portugal is made up of many small growers and a few larger growers. The average pear orchard is two hectares, but 80 percent of the total pear production is from only 20 percent of the growers. Whether large or small, most pear growers are diversified, also growing apples, wine grapes, and vegetables.

Many local pear varieties are produced throughout Portugal, but one variety, Rocha (pronounced "roh-shä"), makes up about 97 percent of total production. Rocha is a relatively small pear with light green skin, which changes to light yellow when ripe. It has a distinctive cap of stem-end –russet and prominent lenticels. More extensive surface russet may develop under humid growing conditions. Most often eaten when the flesh is firm, Rocha has a crunchy texture. The flesh is white with moderate sweetness and mild pear flavor. Although Rocha is harvested in mid-August, it is handled as a winter pear, with fruit from –controlled-atmosphere storage being shipped into June. Postharvest challenges include storage decay and –superficial scald.

Chance seedling

Rocha originated in Portugal and is thought to be a chance seedling discovered by Pedro Rocha on the family quinta (estate) near Lisbon in the mid-1800s. Portugal is still the near-exclusive Rocha-producing country with about 99 percent of world production. In recent years, exports have reached up to a third of the annual Rocha production. Five countries, led by the United Kingdom and Brazil, are the destination for 92 percent of exported Rocha pears. Third-party certification programs such as EurepGAP have become the norm for exported fruit.

Portugal has a Mediterranean climate with predominantly cool, wet winters and warm, dry summers. Within Portugal, Rocha production is centered in the region known as Oeste (west), located on the central coast north of the capital city, Lisbon, where the climate is moderated by close proximity to the Atlantic Ocean. Fruit quality is considered to be the best there and is distinguished with a Protected Designation of Origin, or DOP.

Rocha is often planted in single-variety blocks because in the mild spring weather it sets fruit parthenocarpically, and some Rocha clones are considered to be self-fertile. Gibberellic acid is regularly used, however, to enhance fruit set. Older existing orchards are planted on seedling pear rootstocks, resulting in large, spreading trees, similar to those in older Pacific Northwest pear orchards. Newer orchards are commonly planted at higher densities on clonal quince rootstocks. Even with quince rootstock, growth regulators are regularly used to control tree size in these higher density plantings.

Portuguese pear growers face many of the challenges of Pacific Northwest growers.

Leopard moth

During a symposium field trip, we toured European Union-sponsored field research trials addressing many aspects of sustainable production systems, including training systems, irrigation management, and pest and disease management. In addition to shared pests such as codling moth and pear psylla, Portuguese growers contend with pests such as the leopard moth, whose larvae mine tunnels in the trunks of young pear trees, usually requiring replacement or retraining of the affected trees. Fortunately, the percentage of trees infested is low. Pear scab is a concern during wet spring weather, but fireblight has not yet made its way to Portugal.

Portuguese fruit growers are dependent on a dwindling labor supply, in large part due to depopulation of rural areas as inhabitants move to urban centers in search of higher paying jobs and an easier life. In response, newer plantings are configured as pedestrian orchards with most work done from the ground, or they are adapted to mechanical-assist platforms. We saw several harvest platforms, including some with integrated dry bin fillers.

Despite the challenges, the Portuguese have developed a solid, albeit relatively small, export market for Rocha. Is it a potential variety for U.S. pear growers? Rocha was imported to the United States by Brandt’s Fruit Trees under the name Madeira, and was included in the pear cultivar trial at Oregon State University’s Mid-Columbia Agricultural Research and Extension Center in Hood River. Rocha was moderately productive in Hood River. Russet development was variable, and in some years was limited to the stem end and lenticels. In 2005, when the spring was very wet in Hood River, extensive net-like russet developed on the fruit. Rocha did not perform well in consumer preference surveys conducted in Portland, Oregon. With the current emphasis in domestic markets on large fruit with either clean finish or complete russet, it seems unlikely that Rocha could be a mainstream variety here.