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Key to Nutrient Deficiencies of Deciduous Fruit and Nuts Reviewed: March 2023 Symptoms generally appear first on older leaves. (When youngest leaves are affected oldest leaves usually are falling.) Element Deficient 1. Marked “islands” of chlorosis or nec ...

Fluorine Toxicity in Plants Reviewed: March 2023 Jay W. Pscheidt, Extension Plant Pathology Specialist, OSU Fluorine (F) occurs in the atmosphere as gaseous molecules (F 2) and in reduced form as particulate fluoride (F-). In water, inorganic fluorides us ...

Fungicide and Pollen Interactions Reviewed: March 2023 J.W. Pscheidt, Extension Plant Pathology Specialist, OSU Do fungicides inhibit pollen? Yes, but mostly in the laboratory. Fungicides do not inhibit fruit set and yield. Several fungicides inhibit poll ...

Limes in Sprays for Disease Control Reviewed: March 2023 Hydrated lime (calcium hydroxide) is the lime recommended for preparing bordeaux mixture. Hydrated lime is sold under several trade names or may be prepared by slaking calcium oxide. Do not use othe ...

Powdery Mildew Diseases Reviewed: March 2023 Dean A. Glawe, Plant Pathologist, Emeritus, WSU Gary G. Grove, Plant Pathologist and Extension Plant Pathologist, WSU Powdery mildews rank among the most important diseases of food and ornamental plants. Damage ...

Damping-off in Vegetable Seedlings Reviewed: March 2023 Damping-off frequently attacks young seedlings of almost all kinds of vegetables. Just after seedlings have emerged from the soil, they are easily killed by fungus organisms likely to be present in a ...

Mycotoxins Reviewed: March 2023 Beneficial and harmful products that fungi produce draw researchers’ attention worldwide. Antibiotics inhibit microbial activity when administered at sublethal doses, providing important tools to manage infections, primaril ...

Verticillium Wilt in the Pacific Northwest Reviewed: March 2023 By Jeremiah K. S. Dung, Oregon State University Jerry Weiland, USDA-ARS-Horticultural Crops Research Lab Introduction Verticillium wilt is a serious disease of many economically important agr ...

Plants Resistant or Susceptible to Verticillium Wilt Reviewed: March 2023 Plants Resistant or Susceptible to Verticillium Wilt Resistant or Immune Susceptible Trees beech hackberry mulberry ash fringe tree Prunus spp. birch hawthorn plane tree black locus ...

Plants Susceptible to Sclerotinia sclerotiorum Reviewed: March 2023 Plants Susceptible to Sclerotinia sclerotiorum Scientific Name Common Name Scientific Name Common Name Herbaceous Ornamentals House Plants Aconitum aconitum, monkshood Epipremnum pothos A ...