The Daffodils Speak (Part 4)

Pests and diseases

Pests include viruses, bacteria, and fungi as well as arthropods and gastropods.

Viruses

The Virus can affect the color and shape of the leaves. Up to twenty-five viruses have been described as being able to infect narcissi. These include the Narcissus mottling-associated virus, virus that causes green mottling near leaf tips, degeneration virus, late-season yellows virus which occurs after flowering, streaking the leaves and stems, etc.

Bacteria

The Bacterial disease is uncommon in Narcissus but includes Pseudomonas (bacterial streak) and Pectobacterium carotovorum sp. carotovorum (bacterial soft rot).

Fungi

More problematic for non-commercial plants is the fungus which causes basal rot (rotting of the bulbs and yellowing of the leaves). This is the most serious disease of Narcissus. Since the fungus can remain in the soil for many years it is necessary to remove infected plants immediately, and to avoid planting further narcissi at that spot for a further five years. Not all species and cultivars are equally susceptible. Relatively resistant forms include N. triandrus, N. tazetta and N. jonquilla.

Animals

Arthropods such as three species of fly that have larvae that attack the plants, narcissus bulb fly Merodon equestris, and two species of hoverflies, the lesser bulb flies Eumerus tuberculatus and Eumerus strigatus. The flies lay their eggs at the end of June in the ground around the narcissi, the hatching larvae then burrow through the soil towards the bulbs and consume their interiors.

Planted bulbs are susceptible to nematodes, the most serious of which is Ditylenchus dipsaci (Narcissus eelworm), the main cause of basal plate disease in which the leaves turn yellow and become misshapen. Infested bulbs have to be destroyed; where the infestation is heavy, planting further narcissi for another five years needs to be avoided.

Gastropods such as snails and slugs also cause damage to growth.

Conservation

Many of the smallest species have become extinct, requiring vigilance in the conservation of the wild species. Narcissi are increasingly under threat by over-collection and threats to their natural habitats by urban development and tourism. N. cyclamineus has been considered to be either extinct or exceedingly rare but is not currently considered endangered, and is protected. The IUCN Red List describes five species as 'Endangered' (Narcissus alcaracensis, Narcissus bujei, Narcissus longispathus, Narcissus nevadensis, Narcissus radinganorum).

A number of species have been granted protected species status and protected areas (meadows) have been established such as the Negraşi Daffodil Meadow in Romania, or Kempley Daffodil Meadow in the UK. These areas often host daffodil festivals in the spring.

Of all the flowering plants, the bulbous has been the most popular for cultivation. Of these, narcissi are one of the most important spring-flowering bulb plants in the world. Indigenous in Europe, the wild populations of the parent species had been known since antiquity. Narcissi have been cultivated from at least as early as the sixteenth century in the Netherlands, when large numbers of bulbs were imported from the field, particularly Narcissus hispanicus, which soon became nearly extinct in its native habitat of France and Spain, though still found in the southern part of that country. The only large-scale production at that time related to the double narcissus "Van Sion" and cultivars of N. tazetta imported in 1557.

Cultivation was also documented in Britain, although contemporary accounts show it was well known as a favorite garden and wildflower long before that and was used in making garlands. This was a period when the development of exotic formal gardens and parks was becoming popular, particularly in what is known as the "Oriental Period" (1560–1620).

While Shakespeare's daffodil is the wild or true English daffodil (N. pseudonarcissus), many other species were introduced, some of which escaped and naturalized, particularly N. biflorus (a hybrid) in Devon and the west of England. In the early seventeenth century, Parkinson ensured the popularity of the daffodil as a cultivated plant by describing a hundred different varieties in his Paradisus Terrestris (1629), and introducing the great double yellow Spanish daffodil (Pseudonarcissus aureus Hispanicus flore pleno or Parkinson's Daffodil) to England.

Daffodils did not achieve the importance of tulips. But daffodils and narcissi have been much celebrated in art and literature. The largest demand for narcissi bulbs were large trumpet daffodils, N. poeticus and N. bulbocodium, and Istanbul became important in the shipping of bulbs to western Europe. By the early baroque period, both tulips and narcissi were an important component of the spring garden. By 1739 a Dutch nursery catalogue listed 50 different varieties.

Narcissi became an important horticultural crop in Western Europe in the latter part of the nineteenth century, beginning in England between 1835 and 1855 and the end of the century in the Netherlands. By the beginning of the twentieth century, 50 million bulbs of N. Tazetta "Paperwhite" were being exported annually from the Netherlands to the United States. With the production of triploids such as "Golden Spur", in the late nineteenth century, and in the beginning of the twentieth century, tetraploids like "King Alfred" (1899), the industry was well established, with trumpet daffodils dominating the market. The Royal Horticultural Society has been an important factor in promoting narcissi, holding the first Daffodil Conference in 1884, while the Daffodil Society, the first organization dedicated to the cultivation of narcissi was founded in Birmingham in 1898. Other countries followed and the American Daffodil Society which was founded in 1954 publishes The Daffodil Journal quarterly, a leading trade publication.

Daffodil trumpets

Narcissi are now popular as ornamental plants for gardens, parks and as cut flowers, providing color from the end of winter to the beginning of summer in temperate regions. They are one of the most popular spring flowers and one of the major ornamental spring flowering bulb crops, being produced both for their bulbs and cut flowers, though cultivation of private and public spaces is greater than the area of commercial production. Over a century of breeding has resulted in thousands of varieties and cultivars being available from both general and specialist suppliers. They are normally sold as dry bulbs to be planted in late summer and autumn. Plant breeders have developed some daffodils with double, triple, or ambiguously multiple rows and layers of segments. Many of the breeding programs have concentrated on the corona (trumpet or cup), in terms of its length, shape, and color, and the surrounding perianth or even as in varieties derived from N. poeticus a very reduced form.