Parsnip

The parsnip is a biennial plant with a rosette of roughly hairy leaves that have a pungent odor when crushed. Parsnips are grown for their fleshy, edible, cream-colored taproots. The roots are generally smooth, although lateral roots sometimes form. Most are narrowly conical, but some cultivars have a more bulbous shape, which generally tends to be favored by food processors as it is more resistant to breakage. The plant's apical meristem produces a rosette of pinnate leaves, each with several pairs of leaflets with toothed margins. The lower leaves have short stems, the upper ones are stemless, and the terminal leaves have three lobes. The leaves are once- or twice-pinnate with broad, ovate, sometimes lobed leaflets with toothed margins; they grow up to long. The petioles are grooved and have sheathed bases. The floral stem develops in the second year and can grow to more than tall. It is hairy, grooved, hollow (except at the nodes), and sparsely branched. It has a few stalkless, single-lobed leaves measuring long that are arranged in opposite pairs. The yellow flowers are in a loose, compound umbel measuring in diameter. Six to 25 straight pedicels are present, each measuring that support the umbellets (secondary umbels). The umbels and umbellets usually have no upper or lower bracts. The flowers have tiny sepals or lack them entirely, and measure about . They consist of five yellow petals that are curled inward, five stamens, and one pistil. The fruits, or schizocarps, are oval and flat, with narrow wings and short, spreading styles. They are colored straw to light brown, and measure long. Despite the slight morphological differences between the two, wild parsnip is the same taxon as the cultivated version, and the two readily cross-pollinate. The parsnip has a chromosome number of 2n=22. ==Taxonomy==

's 1796 Deutschlands Flora in Abbildungen Pastinaca sativa was first officially described by Carolus Linnaeus in his 1753 work Species Plantarum. Like most plants of agricultural importance, several subspecies and varieties of P. sativa have been described, but these are mostly no longer recognized as independent taxa, == Distribution and habitat ==

Like carrots, parsnips are native to Eurasia. == Invasivity ==

, Ontario. The parsnip's popularity as a cultivated plant has led to its spread beyond its native range, and wild populations have become established in other parts of the world. A scattered population can be found throughout North America. The plant can form dense stands which outcompete native species and is especially common in abandoned yards, farmland, and along roadsides and other disturbed environments. The increasing abundance of this plant is a concern, particularly due to the plant's toxicity and increasing abundance in populated areas such as parks. Control is often carried out via chemical means, with glyphosate-containing herbicides considered effective. ==Cultivation==

History Zohary and Hopf note that the archaeological evidence for the ancient cultivation of the parsnip is "still rather limited" and that Greek and Roman literary sources are a major source about its early use. Parsnip is used as a food plant by the larvae of some lepidopteran species, including the parsnip swallowtail (Papilio polyxenes), the common swift moth (Korscheltellus lupulina), the garden dart moth (Euxoa nigricans), and the ghost moth (Hepialus humuli). Several fungi are associated with canker, including Phoma complanata, Ilyonectria radicicola, Itersonilia pastinaceae, and I. perplexans. In Europe, Mycocentrospora acerina has been found to cause a black rot that kills the plant early. Watery soft rot, caused by Sclerotinia minor and S. sclerotiorum, causes the taproot to become soft and watery. A white or buff-coloured mould grows on the surface. The pathogen is most common in temperate and subtropical regions with a cool, wet season. Violet root rot caused by the fungus Helicobasidium purpureum sometimes affects the roots, covering them with a purplish mat to which soil particles adhere. The leaves become distorted and discoloured, and the mycelium can spread through the soil between plants. Some weeds can harbour this fungus, and it is more prevalent in wet, acid conditions. Erysiphe heraclei causes a powdery mildew that can cause significant crop loss. Infestation by this causes results in the yellowing of the leaf and loss of foliage. Moderate temperatures and high humidity favor the development of the disease. Several viruses are known to infect the plant, including seed-borne strawberry latent ringspot virus, parsnip yellow fleck virus, parsnip leaf curl virus, parsnip mosaic potyvirus, and potyvirus celery mosaic virus. The latter causes clearing or yellowing of the areas of the leaf immediately beside the veins, the appearance of ochre mosaic spots, and the crinkling of the leaves in infected plants. ==Toxicity==

The shoots and leaves of parsnip must be handled with care, as its sap contains furanocoumarins, phototoxic chemicals that cause blisters on the skin when it is exposed to sunlight, a condition known as phytophotodermatitis. It shares this property with many of its relatives in the carrot family. Symptoms include redness, burning, and blisters; afflicted areas can remain sensitive and discolored for up to two years. Risk can be reduced by wearing long pants and sleeves to avoid exposure, and avoiding sunlight after any suspected exposure. If eyes are exposed to the sap it can cause blindness. The toxic properties of parsnip extracts are resistant to heating and periods of storage lasting several months. Toxic symptoms can also affect livestock and poultry in parts of their bodies where their skin is exposed. Polyynes can be found in Apiaceae vegetables such as parsnip, and they show cytotoxic activities. == Uses ==

Parsnips resemble carrots and can be used in similar ways, but they have a sweeter taste, especially when cooked. They can be baked, boiled, pureed, roasted, fried, grilled, or steamed. When used in stews, soups, and casseroles, they give a rich flavour. In some cases, parsnips are boiled, and the solid portions are removed from the soup or stew, leaving behind a more subtle flavour than the whole root and starch to thicken the dish. Roast parsnip is considered an essential part of Christmas dinner in some parts of the English-speaking world and frequently features in the traditional Sunday roast. Parsnips can also be fried or thinly sliced and made into crisps. They can be made into a wine with a taste similar to Madeira. In Roman times, parsnips were believed to be an aphrodisiac. Nutrition A typical 100 g serving of parsnip provides of food energy. Most parsnip cultivars consist of about 80% water, 5% sugar, 1% protein, 0.3% fat, and 5% dietary fiber. The parsnip is rich in vitamins and minerals and is particularly rich in potassium with 375 mg per 100 g. The consumption of parsnips has potential health benefits. They contain antioxidants such as falcarinol, falcarindiol, panaxydiol, and methyl-falcarindiol, which may potentially have anticancer, anti-inflammatory and antifungal properties. The dietary fiber in parsnips is partly of the soluble and partly the insoluble type and comprises cellulose, hemicellulose, and lignin. The high fiber content of parsnips may help prevent constipation and reduce blood cholesterol levels. == In culture ==

The parsnip was much esteemed in Rome, and Emperor Tiberius accepted part of the tribute payable to Rome by Germania in the form of parsnips. In Europe, the vegetable was used as a source of sugar before cane and beet sugars were available. == See also ==