Southern Blight

Authors: Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Last Revised: 01/03/2019 X-number: XHT1042   What is Southern blight?  Southern blight is a lethal fungal disease that is most common in the tropics and subtropics.  This disease causes damage in the southern U.S. and can even cause problems in temperate locations like Wisconsin during periods of warm, moist […]

Septoria Leaf Spot

Brian Hudelson, UW-Madison Plant Pathology Revised:  3/10/2012 Item number:  XHT1073 What is Septoria leaf spot?  Septoria leaf spot is one of two common fungal diseases that can devastate tomatoes in both commercial settings and home gardens.  The second common tomato blight, early blight, is detailed in University of Wisconsin Garden Facts XHT1074. What does Septoria […]

White Mold

Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Revised:  4/25/2004 Item number:  XHT1115 What is white mold?  White mold is a serious, and often lethal, fungal disease that affects over 374 types of plants in many plant families.  It causes severe damage in commercial snap, kidney and lima bean production, as well as commercial sunflower […]

Early Blight

Brian Hudelson, UW-Madison Plant Pathology Revised:  3/10/2012 Item number:  XHT1074 What is early blight?  Early blight is one of two common fungal diseases that can devastate tomatoes in both commercial settings and home gardens.  Early blight can also be a serious disease on other popular vegetables including eggplants, peppers, and potatoes.  The second common tomato […]

Dodder

Jennifer Clifford, Amilcar Sanchez, Trenton Stanger, and Brian Hudelson,UW-Madison Plant Pathology Revised:  10/21/2006 Item number:  XHT1156 What is dodder?  Dodder is the name of several species of parasitic plants that are widely distributed in North America and Europe.  Plants parasitized by dodder include alfalfa, carrots, onions, potatoes, cranberries, a variety of herbaceous and woody ornamentals, […]

Cucumber Beetles

Authors: David M. Lowenstein and Russell L. Groves, UW-Madison, Department of Entomology Last Revised: 05/01/2020 X-number: XHT1092 Striped and spotted cucumber beetles are common pests of vine crops (e.g., cucumber, squash, pumpkin, watermelon) that can cause severe damage to roots, leaves, flowers and fruits, as well as interfere with pollination, leading to reduced fruit set.  In Wisconsin, the […]

Tobacco Rattle

Rachel Zwieg* and Brian Hudelson, UW-Madison Plant Pathology *Completed as partial fulfillment of the requirements for the Horticulture track of the Farm and Industry Short Course program at the University of Wisconsin Madison. Revised:  8/19/2010 Item number:  XHT1180 What is tobacco rattle? Tobacco rattle is a common and potentially serious viral disease that affects a […]

Corky Ringspot

Brian Hudelson and Amy Charkowski, UW-Madison Plant Pathology Revised:  8/19/2010 Item number:  XHT1186 What is corky ringspot? Corky ringspot (also known as spraing) is a potentially serious viral disease of potato that has recently been detected in Wisconsin.  The disease can cause severe losses due to the fact that it reduces potato tuber quality, making […]

Blossom End Rot

Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Revised:  4/1/2005 Item number:  XHT1140 What is blossom end rot? Blossom end rot is a physiological disorder of tomato in which the tissue of the blossom end of the fruit (the portion of the fruit opposite the stem) breaks down and rots, thus reducing yield.  Pepper, eggplant […]

Downy Mildew

Jim Olis* and Brian Hudelson, UW-Madison Plant Pathology *Completed as partial fulfillment of the requirements for a BS in Plant Pathology at the University of Wisconsin Madison. Revised:  8/6/2012 Item number:  XHT1077 What is downy mildew? The downy mildews are a group of fungal diseases that cause destruction of the leaves, stems, flowers and fruits […]

Late Blight

Amanda Gevens, Anna Seidl, Brian Hudelson, UW-Madison Plant Pathology Revised:  June 16, 2017 Item number:  XHT1195 What is late blight?  Late blight is a destructive disease of tomatoes and potatoes that can kill mature plants, and make tomato fruits and potato tubers inedible.  This disease also affects, although typically to a lesser extent, eggplants and […]

Black Walnut Toxicity

Ann Joy and Brian Hudelson, UW-Madison Plant Pathology Revised:  5/7/2010 Item number:  XHT1017 What is black walnut toxicity? Black walnut trees (Juglans nigra) produce a toxic substance (called juglone) that prevents many plants from growing under or near them. Related trees like butternut (J. cinerea) and shagbark hickory (Carya ovata) also produce juglone, but in […]

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