TULIP

The tulip is a Eurasian and North African genus of perennial, bulbous plants in the lily family. It is a herbaceous herb with showy flowers, of which around 75 wild species are currently accepted.

The genus's native range extends west to the Iberian Peninsula, through North Africa to Greece, the Balkans, Turkey, throughout the Levant (Syria, Israel, Palestinian Territories, Lebanon, Jordan) and Iran, north to Ukraine, southern Siberia and Mongolia, and east to the Northwest of China. The tulip's centre of diversity is in the Pamir, Hindu Kush, and Tien Shan mountains. It is a common element of steppe and winter-rain Mediterranean vegetation.

A number of species and many hybrid cultivars are grown in gardens or as potted plants.

Description

Tulips are spring-blooming perennials that grow from bulbs. Depending on the species, tulip plants can be between 4 inches (10 cm) and 28 inches (71 cm) high. The tulip's large flowers usually bloom on scapes with leaves in a rosette at ground level and a single flowering stalk arising from amongst the leaves.Tulip stems have few leaves. Larger species tend to have multiple leaves. Plants typically have two to six leaves, some species up to 12. The tulip's leaf is strap-shaped, with a waxy coating, and the leaves are alternately arranged on the stem; these fleshy blades are often bluish green in color. 

Most tulips produce only one flower per stem, but a few species bear multiple flowers on their scapes (e.g. Tulipa turkestanica). The generally cup or star-shaped tulip flower has three petals and three sepals, which are often termed tepals because they are nearly identical. These six tepals are often marked on the interior surface near the bases with darker colorings. Tulip flowers come in a wide variety of colors, except pure blue (several tulips with "blue" in the name have a faint violet hue).

The flowers have six distinct, basifixed stamens with filaments shorter than the tepals. Each stigma has three distinct lobes, and the ovaries are superior, with three chambers. The tulip's seed is a capsule with a leathery covering and an ellipsoid to globe shape. Each capsule contains numerous flat, disc-shaped seeds in two rows per chamber. These light to dark brown seeds have very thin seed coats and endosperm that does not normally fill the entire seed.

Phytochemistry

Tulipanin is an anthocyanin found in tulips. It is the 3-rutinoside of delphinidin. The chemical compounds named tuliposides and tulipalins can also be found in tulips and are responsible for allergies. Tulipalin A, or α-methylene-γ-butyrolactone, is a common allergen, generated by hydrolysis of the glucoside tuliposide A. It induces a dermatitis that is mostly occupational and affects tulip bulb sorters and florists who cut the stems and leaves. Tulipanin A and B are toxic to horses, cats and dogs.

Growing wild over much of the Near East and Central Asia, tulips had probably been cultivated in Persia from the 10th century. By the 15th century, tulips were among the most prized flowers; becoming the symbol of the later Ottomans. Tulips were cultivated in Byzantine Constantinople as early as 1055 but they did not come to the attention of Northern Europeans until the sixteenth century, when Northern European diplomats to the Ottoman court observed and reported on them. They were rapidly introduced into Northern Europe and became a much-sought-after commodity during tulip mania. 

Tulips were frequently depicted in Dutch Golden Age paintings, and have become associated with the Netherlands, the major producer for world markets, ever since. In the seventeenth century Netherlands, during the time of the tulip mania, an infection of tulip bulbs by the tulip breaking virus created variegated patterns in the tulip flowers that were much admired and valued. While truly broken tulips are not cultivated anymore, the closest available specimens today are part of the group known as the Rembrandts – so named because Rembrandt painted some of the most admired breaks of his time.

Breeding programmes have produced thousands of hybrid and cultivars in addition to the original species (known in horticulture as botanical tulips). They are popular throughout the world, both as ornamental garden plants and as cut flowers.