Tamra Jackson-Ziems, Extension Specialist and Associate Professor, joined the faculty of the Department of Plant Pathology at the University of Nebraska-Lincoln (UNL) in April 2005 after completing her graduate degrees at the University of Arkansas and University of Illinois-Urbana. Her appointment is split between extension, research, and teaching 80/10/10%, respectively, with statewide responsibility for diseases of corn and grain sorghum. Her extension activities encompass educating clientele about disease identification, prevention, and management. And her research projects encompass a broad range of topics, including bacterial leaf streak, Goss’s bacterial wilt and blight, use of fungicides for disease control, and plant parasitic nematodes of corn. During her time at UNL, she has delivered more than 180 invited presentations in 16 states and is the 2016 recipient of both the Nebraska Cooperative Extension Association’s Award for Outstanding Creative Programming (for an individual) and the Nebraska Ag Business Association’s Education and Research Person of 2016 Award.
icon-academic-capEducation
Ph D, University of Illinois-Urbana, 2005
MS, University of Arkansas, 2000
BS, University of Central Arkansas, 1996
icon-bookmark-starAwards & Honors
Outstanding Education and Research Person of 2016, Nebraska Ag Business Association, 2016
Outstanding Award For Creative Programming (Individual) for "Bacterial Leaf Streak of Corn", Nebraska Cooperative Extension Association, 2016
Dinsdale Family Faculty Award, IANR, 2009
Distinguished New Extension Employee Award , UNL Extension, 2009
Bacterial leaf streak was first confirmed in the US in August 2016 when it was identified in Nebraska corn. It has now been confirmed in 51 Nebraska counties and found in corn fields across the Midwest. This article offers information on current status, identification, and management of the disease. Resistance is not currently available in hybrids and standard management measures of bacterial diseases will help mitigate but not eliminate damage.
A review of 2016 growing conditions across Nebraska sheds light on a number of factors that may have contributed to reduced yield in individual fields. An understanding of these factors may be helpful when selecting seed for 2017.
Figures 1a and b. Growth of fungi feeding on dead/decaying tissue and their black spores on corn husks (a) (and other plant parts) may give it a dark, dusty appearance, especially during harvest. The ear itself is usually unaffected by these fungi (b).
Ear rot diseases have been observed and stalk rot diseases are becoming increasingly common. It’s important to scout for stalk rot diseases now to determine which fields are at greatest risk of lodging and should be harvested first. Although it is unknown if ear rot diseases are widespread, it’s also important to scout for ear rot diseases to know how to better handle affected grain at harvest to prevent or minimize impacts on grain quality.
The tops of corn plants that have Anthracnose stalk rot top dieback may break off prior to harvest, but are not always an indicator of stalk and crown rot lower on the plant.
Stalk rot diseases are increasing in corn, causing top die-back in a number of fields, and ear rot diseases are developing in some fields. Scout fields now to help determine the need for any adjustments in your harvest management.
While most of the Nebraska corn crop looks good, there is early evidence of developing stalk and crown rot diseases, including Anthracnose top dieback. Producers are encouraged to scout their fields for disease and prioritize those fields for harvest where lodging may become an issue.
Bacterial leaf streak disease of corn, caused by Xanthomonas vasicola pv. vasculorum, has now been confirmed in multiple Corn Belt states. First identified in Nebraska, the bacterial disease has symptoms similar to other corn diseases, such as gray leaf spot, but is managed differently.
UNL agronomists and educators responding to grower questions surveyed a number of corn fields this week and found a range of corn ear issues: short husks, dumbbell-shaped ears, and multiple ears per node. The article describes and discusses the situation, potential stress agents, and the development of corn. It also encourages growers to check their fields pre-harvest to better assess causes of potential yield loss.
