This talk aims to tune up your ability to spot spots on greenhouse and field flowers, foliage and herbaceous perennials. Expect to learn how to recognize bacterial spots such as those seen on poinsettia, zinnia, geranium, ivy, and ornamental kale; fungal leaf spots such as those caused by Cercospora on pansy, measles on peony, Septoria on rudbeckia, Colletotrichum on ivy and pigsqueak, Alternaria on zinnia and Botrytis on many things; downy mildew spots on coleus, geum and digitalis; rust spots on chrysanthemum and snapdragon; and virus spotting from Hosta Virus X on hosta, plus spotting from Tomato spotted wilt virus and Impatiens necrotic spot virus on lots of crops. Fungicides and bactericides helpful for protecting against spots will be presented, explaining their mode of action (FRAC) groups. Cultural techniques for minimizing spots will be emphasized. SPEAKER: MARGERY DAUGHTREY, CORNELL UNIVERSITY
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