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Plant NameTypeDescription 
Basal rotNarcissus (Daffodil)DiseaseBasal rot of narcissus is caused by a soilborne fungus. Bulbs usually develop the rot during storage. The infection begins at wound sites or at the base of the bulb in the root plate and progresses into the bulb. The affected tissue turns brown to purplish-red in color. The fungus is present between bulb scales as a growth of whitish to pink mold. Plants grown from infected bulbs are stunted and yellowed, and develop few roots.
FireNarcissus (Daffodil)DiseaseNarcissus fire is a fungal disease which affects the petals and leaves, but does not affect the bulb. It is favored by warm, humid weather and can spread very quickly under these conditions. Flowers are attacked first, with watersoaked spots appearing at the margins and enlarging rapidly. The spots later turn brown and wither. Leaf infections follow flower infections. Initial leaf symptoms include development of yellow, elongate spots near leaf tips. The centers of the spots turn grayish or brown as the spots enlarge. The leaf above the infection point dies and droops. The fungus survives in infected plant tissues and on plant debris in the soil.
Leaf scorchNarcissus (Daffodil)DiseaseLeaf scorch is caused by a fungus that survives in the necks of the bulbs (thus infecting emerging leaves) and also in infected foliage. Leaf tips develop yellow-brown to reddish elongate spots or blotches soon after they emerge from the bulb. The spots become raised and scabby, with tiny brown fruiting bodies of the fungus in the scabby area. This disease can also cause bud distortion and brown spotting of flowers.
Stem and bulb nematodeNarcissus (Daffodil)DiseaseNematodes are tiny (often microscopic), parasitic worms that live in the soil and in infected plant parts. The stem and bulb nematode of narcissus feeds mainly on aboveground portions of the plant. The initial symptom is the presence of small swellings or "spikkels" on the leaves. Foliage is distorted and turns yellow or brown in affected areas. Flowers may be delayed or absent. The nematodes may move into the bulb, causing brownish areas in the bulb tissue and sometimes causing softening or rotting of stored bulbs. Plantings infested with nematodes often show circular areas of stunted or prematurely yellow plants. These patches expand gradually.
Virus diseasesNarcissus (Daffodil)DiseaseWhile many viruses infect narcissus, two virus diseases (Yellow Stripe and White Streak) are common in the Pacific Northwest. Yellow Stripe is characterized by the white mottling or streaking of the flower and streaking of the upper 2/3 of the foliage with pale green to yellow stripes. The affected foliage also develops a rough texture and may be stunted or distorted. Yellow Stripe Virus is transmitted by aphids. White Streak is characterized by the appearance of very narrow dark green to purplish stripes on the foliage and flower stems. These later turn white and necrotic. Affected leaves die. White Streak Virus is transmitted by aphids and often appears after periods of high temperature and strong sunlight.
Narcissus bulb flyNarcissus (Daffodil)InsectThe adult narcissus bulb fly is about 1/2" long and closely resembles a small bumblebee. The female lays eggs near the bulbs in early summer. The hatching maggots burrow into the bulbs near the basal plate and feed inside the bulbs, destroying bulb scales and flower parts. Infested bulbs may develop a few, grassy-looking leaves if the bulb is not too badly damaged. Severely damaged bulbs are soft, brown, and decayed, with a 3/4", yellowish white larva inside.