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Asian Soybean Rust - Frequently Asked Questions III: Control with Fungicides
... to be scouted on a regular basis for signs of infection of new leaf tissue. Which maturity group should I spray first? Crops in vegetative stages should not ... curative fungicide. Protectant fungicides prevent fungi from successfully infecting and/or penetrating host tissue. Protectants include chlorothalonil and the strobilurins (azoxystrobin, pyraclostrobin, trifloxystrobin, etc.). These products ...
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Asian Soybean Rust - Frequently Asked Questions V: Monitoring, Tracking, and Scouting
... a sealable plastic bag. Keep leaf tissue from damage or drying out during transport to a Virginia Cooperative Extension office or plant diagnostic lab. Keep the tissue in a sealable plastic bag ... will be observing forecasting models, tracking rust movement through the United States, and evaluating leaf samples submitted by the Virginia Soybean Aphid and Rust Monitoring Program and other first ...
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Home Hydroponics
... die Calcium Leaf tissue between the veins is lighter in color; yellowed; papery in appearance Zinc Leaf tissue appears yellow, while the veins remain green Iron Leaf edges appear dark green or blue; leaf edges curl ...
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Angular Leaf Spot of Cucumber
... , Virginia Tech Publication Number: 450-700, Posted December 2000 Angular leaf spot of cucurbits is caused by the bacterium Pseudomonas syringae pv ... important on cucumbers in Virginia. Fig. 1. Angular leaf spot sumptoms on a squash leaf. (Photo by R. L. Wick-U. Mass.). ... lesions and dries to form a thin, white crust. Affected leaf tissue often dries and drops out, leaving irregularly shaped holes in ...
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Anthracnose - A Fungal Disease of Shade Trees
... leaf tissue caused by the sycamore anthracnose fungus. (Photo by E. Dutky-U. Md.). Fig. 2. Twig canker caused by the sycamore anthracnose fungus. (Photo by E. Dutky-U. Md.). Fig. 3. Leaf ... it to borer attack and winter injury premature leaf drop, which lessens the shade and ornamental value ... diseases may occur. Symptoms of spot anthracnose include tiny leaf and bract spots, about the size of a ...
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Azalea Leaf and Flower Gall
... (Fig. 1). The swollen plant tissues or "galls" are made up of abnormal plant tissue. Infected leaf tissue is usually pale green in color during the early stages of the disease; infected ... susceptible to this disease. Table 1. Cultivars of azalea exhibiting resistance or susceptibility to azalea leaf and flower gall Highly Susceptible Azalea Cultivars China Seas Hinodeii White Gumpo Copperman Mother' ...
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Rose Black Spot
... upper sides of leaves. Leaf tissue adjacent to the spot turns yellow. Whole leaves eventually turn yellow and fall prematurely. Black spot can be distinguished from other leaf spot diseases of rose ... reduce the amount of overwintering fungus. During the growing season, overhead irrigation, which prolongs leaf wetness, should be avoided. If plants are overhead irrigated, watering should be done in ...
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DETERMINING THE CAUSE OF PLANT PROBLEMS
... flowers? Many diseases can cause spots on plants. Is there discoloration in the vascular tissue (inside the plant)? This was the case with a bacterial wilt problem in a ... leaves. Phosphorus - purple coloration of leaves and plants may be stunted. Potassium - brown leaf margins and leaf curling. Magnesium - interveinal (between the veins) chlorosis (yellowing) Boron - development of lateral growth ...
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Entomosporium Leaf Spot of Photinia
... Indian hawthorn (Rhaphiolepis indica), and mountain ash (Sorbus sitchensis). Fig. 1. Leaf spots on photinia caused by Entomosporium mespili. (Photo by R. C. ... fraseri, the tiny, new, circular leaf spots are a darker red than the surrounding healthy tissue. Older necrotic spots (up to 3- ... (Fig. 3) that are dispersed by splashing water to healthy tissue. Symptoms first appear on the new growth of the ...
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Gray Leaf Spot Disease of Corn
... zeae-maydis, causal agent of gray leaf spot disease. Fig. 2. Characteristic mature gray leaf spot lesions on corn leaf. Note the grayish cast ... blighting caused by gray leaf spot. Fig. 5. Typical gray leaf spot lesion on leaf sheath. In Virginia gray leaf spot disease of corn (Fig. ... soil. It can only overwinter within and on dead corn tissue remaining on or above the soil surface. Disking does not ...
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