Arugula: A Promising Specialty Leaf Vegetable

INTRODUCTION Arugula is a collective name for a number of species of the Brassicaceae with pungent leaves, but principally Eruca sativa Mill. This species has been known since antiquity and is listed in the Greek herbal of Dioscorides (Materia Medica) written in the first century (Fig. 1) as well as the English herbal of John Gerard (1597). Arugula is a low-growing annual with dull-green, deeply-cut, compound leaves which have a distinct spicy-pungent flavor (Palada and Crossman 1999). Like other Brassicas, it contains glucosides such as allyl sulphonocyanate while the seed oil contains erucic acid (Nuez and Hernandez 1994). In various Mediterranean countries it is cultivated as a salad green or cooked vegetable and is also grown in Asia as an oilseed crop. Three species are used for human consumption: E. sativa and a wild type E. sativa vesicaria (L.) Cav., both annuals; Diplotaxis tenuifolia (L.) DC, a perennial species, and D. muralis (L.) DC, a polyploid perennial (Pignone 1997). Arugula is also known as rocket (English), roquette (French), rucola or rughetta (Italian). Arugula is widely consumed in Italy where its pungent qualities are appreciated, either consumed alone as a green, as part of a salad mix, as a cooked green, and now very popular as a pizza topping. The wild form with thin dentated leaves is increasing in popularity. Arugula has appeared in US markets from California production and can be found in select supermarkets as a specialty green and it is often found in farmer’s markets as part of a mesclun mix. Arugula is a fast growing, cool-season crop and flowers under long days and high temperature. This crop appears well adapted to the Midwest and offers the possibility of a specialty green that could be available over a long period with season extension techniques as it is adapted to greenhouse culture. Our trials indicate it can be harvested after 20 to 27 days and then sequentially harvested from regrowth. European interest in promoting this underutilized crop has prompted the formation of the Rocket Genetic Resources Network, a project of the International Plant Genetic Resources Institute (IPGRI). The proceedings of a 1996 workshop (Rocket: A Mediterranean crop for the world) contains a number of papers on its culture and biology (Padulosi and Pignone 1997).