Useful information

Diseases and pests of gladioli

To prevent the onset of diseases, I spray the plantings of gladioli every 2-3 weeks with a solution of Fundazol (10 g per 10 l of water), a 1% solution of Bordeaux liquid, a solution of manganese-sour potassium (3 g per 10 l of water), 0, 5% solution of copper oxychloride, alternating them. In addition, a couple of times a season I treat plantings with insecticides to combat thrips.

Diseases

Fusarium, or dry rot... This is the most dangerous fungal disease. It affects the corms, leaves and stem of the plant. At first, it does not manifest itself in any way, but in the 5-6 leaf phase, the leaves begin to turn yellow, first the lower ones, from the tips, then the yellowing spreads to the base. On the corm, brown spots appear on the bottom and in the places of attachment of the scales. If the gladiolus is severely affected, then the corm dies during the growing season. If slightly damaged, it may die during winter storage.

Fusarium gladiolus

Control measures:plants,affected during the growing season, it is better to dig up and burn, and treat the hole with a fungicide.

Gray rot. Another common disease is gray rot caused by the fungus Botrytis. Damp cool weather contributes to the development of the disease. Small brown-brown spots appear on the leaves and stem, which, merging, form large areas. With a strong lesion, the infection spreads down the stem to the corm, affecting its core, root system and base of the stem. In this case, the plant breaks in this place and lays down. Discolored watery spots appear on the petals of the flowers, and with severe damage, the buds become brown and do not open. On the corm, dark brown-brown spots can be observed at the points of attachment of the scales. If the lesion is strong, then during storage it dies.

Control measures: in order to prevent the occurrence of fungal diseases, it is necessary to observe crop rotation, carefully remove plant residues from the site; it is necessary to improve the structure of the soil, lime acid; sunny location of plantings, moderate use of nitrogen fertilizers, treatment of corms before planting and preventive treatment of gladioli during the growing season with fungicides. Proper drying and storage of planting material give positive results.

Gladiolus bulbs after preliminary dryingGladiolus bulbs - juvenile and adult, prepared for storage

Gladiolus cancer... Of the bacterial diseases, one of the most common isgladiolus cancer. It can be found when digging plants, when we observe a growth on the replacement corm, which is sometimes larger in size than the corm itself and has a bumpy surface. During the growing season, many leaves from the sprouting baby appear around the stem (with severe damage).

Control measures: the diseased plant is destroyed.

Bacterial gladiolus cancer

Healthy replacement bulbs grown

from sick mother bulbs with scab

Bacteriosis, bacterial scab, gladiolus varnish disease... The first signs of bacterial scab are the appearance of small reddish-brown spots in the lower part of the plant, as well as on the leaves and stem, which gradually merge and turn into longitudinal brownish stripes.

Wet weather contributes to the development of the disease. With a strong spread of scab, the stem in the affected areas may break. Round brown shiny spots appear on the corm. These stains are easy to remove. The presentation of the bulb is deteriorating, but the disease does not spread further and does not affect the development and flowering of plants in the next season.

Under favorable conditions, a completely healthy plant can grow from severely affected bulbs next year.

Control measures: the same as with fusarium.

Bacterial gladiolus scabScab on maternal gladiolus bulbs

Viral diseases. The first group of viral diseases includes mosaics, in which striping, streaking, speckling appear on the leaves, and the flower becomes variegated, intermittent striping appears, there may be white and green spots uncharacteristic of the variety. In affected plants, leaves may die off, the corm becomes smaller and gives weak, non-flowering plants.

The second group of viral diseases includes jaundice, in which the leaves can turn yellow, and the flowers acquire a green color, and grassiness also appears, when instead of a strong sprout, several weak shoots are formed.

Jaundice (grassiness) of gladiolus

Control measures: diseased plants need to be dug up with a clod of earth and destroyed, as well as to fight the carriers of the virus - leafhoppers.

Pests

Thrips... The greatest harm to gladioli causesthrips is a small sucking insect that feeds on plant sap. The activity of thrips leads not only to the weakening of the plant and the loss of decorativeness, it is also a carrier of viral diseases. With a weak lesion, colorless silvery spots appear on the perianth lobes, which reduce the decorative effect of the flower. With severe damage, the buds may not open at all, and if you break such a bud, you can see yellow larvae. In autumn, when the air temperature drops below + 10 ° C, thrips migrates to the corm. If, after digging, the planting material is not treated with insecticides, and then stored in a warm room, you can lose the entire collection, because the thrips will feel very comfortable.

Thrips, an adult insect on a flower

Discolored spots on thrips infested flower

Gladiolus bulbs weakly affected by thripsGladiolus bulbs heavily affected by thrips

Control measures: spraying the plantings of gladioli with insecticides during the growing season at least 3 times per season, and it is also mandatory to treat the corms after digging.

Wireworm... Dangerous for gladiolus and wireworm, the larva of the click beetle. He bites into the corms and eats away its contents. The plant may die. But, even if the damage to the corm is insignificant, pathogens of fungal diseases can get into the wounds inflicted by the wireworm.

Gladiolus bulbs weakly affected by wireworm

Control measures: you should not plant gladioli after carrots and potatoes, but after legumes, tomatoes and garlic, on the contrary, it is good; do not plant gladioli in areas clogged with wheatgrass.

Read also the article Cleaning and storage of gladiolus bulbs

Photo by the author

"Garden for the soul and good rest", No. 7, 2014 (Nizhny Novgorod)

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