Fire blight

Thomson SV (1996) Solarization of pear and apple trees to eradicate bacteria in fire blight cankers. Acta Hort (ISHS) 411 337-340... 

The control of bacterial diseases with the currently available products Is very unsatisfactory. The problem has become urgent with the spread of fire blight (Erwlnla amylovora) In Europe, and the Increased Incidence of bacterial leaf blight of rice (Xanthomonas oryzae) and citrus canker (Xanthomonas cltrl) as well as many other bacterial diseases. The direct control of virus diseases Is cur-... 

Apples, pears fire blight Erwinia amylovora 46-48... 

Even if the use of synthetic plant protection products is required by the authorities (compulsory phytosanitary measures, e.g. in cases of fire blight), the product shall not be labelled as organically produced. 

Cause Fire blight. This bacterial disease causes... 

Pests and disease problems on apple trees are covered in the Apple entry beginning on page 21. Crab apples share many of the same problems, including fire blight, cedar-apple rust, powdery mildew, and apple scab. Ibr-tunately, disease-resistant cultivars are available. Some of the best include Adams , with reddish pink flowers Coral Cascade , with white flowers Prarifire , with purplish red flowers and Professor Sprenger , with white flowers. There are also many other resistant cultivars, so check with your local nursery owner or extension agent to learn about the best ones for your area. 

Leaves suddenly blacken, with tips of growing shoots bent over. Cause Fire blight. Don t confuse this bacterial disease with sooty mold, a black fungus that rubs off easily. Fire blight bacteria enter the tree at the growing tips and may travel down toward the roots and kill the whole tree. 

Cause Fire blight. For more information and controls, see Leaves, flowers, and branches blackened on page 192. 

Blights When plants suffer from blight, leaves or branches suddenly wither, stop growing, and die. Later, plant parts may rot. Common blights include fire blight, Alternaria blight, and bacterial blights. 

About 200 different bacteria are responsible for plant diseases. Warmth and moisture are most conducive to bacterial growth, so bacterial diseases generally are worse in warm. humid climates. Hence, pears, which are subject to the bacterial disease fire blight, are not extensively grown on a commercial scale in the hot, humid Southeast. 

One distinctive symptom of sonre bacterial diseases is the sticky, gummy material secreted by active bacterial cells. If the leaves on your cucumber plant arc wilting and you suspect bacterial wilt disease, cut the stem or leaf stalk with a sharp knife. If you see threads of slime when you pull the stem or stalk apart, this confirms bacterial wilt disease. Active fire blight cankers are covered with a similar bacterial slime. In many cases the bacterial slime has an unpleasant odor. 

Remember that humans also can be vectors of disease. You can carry crown gall from an infected plant to a healthy plant on a shovel you use for planting, or fire blight from one branch to the next on infected pruning shears. Your tomato plants could become infected with tobacco mosaic virus if you handle the plants after touching cigarettes or other tobacco products infected with tobacco mosaic virus. 

One approach in biological control is to make the pathogens sick. Bacteriophages, which are viruses that infect bacteria, have been used experimentally to infecrand weaken the bacteria that cause bacterial wilt of tomatoes and fire blight on pears. 

Stem tips may die back as a result of disease problems, such as fire blight, or from physical damage to the plant. 

Fruit trees infected by fire blight benefit from pruning that removes blighted twigs and disease cankers and stimulates air flow through the branches. 

Protection Offered Bordeaux mix acts as a fungicide with insecticidal and insect repellent properties. Use it to control common plant diseases like anthracnose, bacterial leaf spots and wilts, black spot, fire blight, peach leaf curl, powdery mildew, and rust. 

Photographic reducer and developer reagent for the determination of small quantities of phosphate, dye intermediate stabilizer in paints and varnishes motor fuels and oils antioxidant for fats and oils, and a polymerization inhibitor. Therapeutically used topically for depigmentation to treat skin blemishes, for example, hypermelanosis. Hydroquinone occurs naturally, as a conjugate with jS-o-glucopyranoside, in the leaves, bark, and fruit of a number of plants, and its presence may be an important factor in fire-blight resistance in the pear. It may also play an important part in the defense mechanisms of some insects. 

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