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Leaf and Bud Eelworms



P_lfandbdelwrm

Leaf and Bud Eelworms

Usually appear in

Summer to Autumn


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Caused By:-     Various Genus and species of Nematodes

Description

There are several Genus and species of leaf and bud eelworms which are microscopic nematodes and not visible to the naked eye. They causes the foliage to turn yellow in patches between the leaf viens, which then turn brownish-black without the formation of spores.
Most attacks of eelworm are caused by the eelworm Aphelenchoides ritzemabosi, which tends to attack the leaves and another A. fragariae tends to start their attacks in the buds, which often show no sign.
In the early stages of infestation, the affected parts of the leaves appear to yellow in well defined areas between the larger leaf veins. As time goes by the entire leaf is invaded and becomes yellow, then brown and eventually falling off. Older and lower leaves are usually attacked first then spreading up the stems, via wet areas, to attach new leaves.
Ellworm attack is mainly a problem of late summer or early autumn. Susceptible plants are African Violets, Anemone, Begonias, Buddleja, Chrysanthemums, Ornamental Fern and Penstemon. Some plants like Buddleja may not show obvious leaf colour variations, but the flower spikes may be small and contain many aborted flowers.
The Leaf eelworms are difficult plant parasites to detect. These nematodes are found in damp soil and can attack both plants and animals. To detect eelworms, break rather than chop affected leaves into tiny bits, and leave in a glass of water for 30 minutes. Tiny, moving masses of eelworms would then be seen at the bottom of the glass of water.
These Nematodes feed on the leaf cells from between the top and bottom epidermal surfaces. They enter the leaf through natural openings like stomata from the layer of infected water. They also secrete compounds that affected the development of plant tissues. They over-winter in dead infested leaves on the ground or between infected bud scales. The entire life cycle, of the eggs, larval stages, and an adults takes place within the leaf. From egg to adult takes 10-12 days when temperatures are between 18-25C (65-75F). Some species can spend part of its life cycle in the ground when infested leaves fall off or are washed into the soil during periods rain or watering.
See also these other Eelworms CHAFER GRUBS, CHRYSANTHEMUM EELWORM, DIEBACK, EELWORMS, ENCHYTRAEID WORMS, IRIS BORER CATERPILLARS, LEATHERJACKETS, LILY VIRUSES, NUT WEEVIL, ONION EELWORM, NARCISSUS EELWORM, PEA AND LEAF POD SPOT, PHLOX EELWORM, POTATO CYST EELWORM, ROOT KNOT EELWORMS, SLUGS, SNAILS, STEM AND BULB EELWORM, TOMATO CYST EELWORMS, VINE WEEVIL, WILTING, WIREWORM, WORMS.


Control

Keep the leaves and stems of your plants reasonably dry as wet foliage allows the spread of the eelworms.
Remove and destroy all affected leaves and stems, and if the infestation is severe, the whole plant as well.
Propagate new plants from the old by using the hot-water treatment method which should kill any remaining eelworms but does not harm the plant. Take a non-infested part of the plant stool during its dormant period, removing the leaves and soil and totally immerse it in hot water at 45C (115F) water for 5 minutes. Place the stool in cold water to cool it then grow it on in clean compost.
A systemic insecticide may kill some eelworms.
In the UK, broad-leaved dock is a host for the potato eelworm, Ditylenchus destructor therefore keeping the area weed free will help prevent attack from eelworm.
Distortion on phlox could indicate the presence of phlox eelworm.
Eelworms can also be the transmitters of viruses.
Soil sterilants remain effective against soil-dwelling species.



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