Variety screening identifies potatoes with resistance to zebra chip disease

by Kay Ledbetter, Texas A&M AgriLife

The Texas A&M AgriLife Research plant pathology team in Amarillo intentionally infected potato plants with psyllids positive with the bacterium that causes zebra chip, a deadly disease plaguing the potato industry for the past 15 years.

The outcome is some promising germplasm that will help in the battle against the costly disease, said Dr. Charlie Rush, plant pathologist. Continue reading

New spray guide helps watermelon producers with fungicide decisions

In Southeast Farm Press

South Carolina watermelon producers now have information they need to make their 2017 crops more profitable with the release of the updated Watermelon Spray Guide for 2017, which includes updated recommendations for battling blight.

Released by the Clemson University Cooperative Extension Service, this guide provides growers with a look at some major diseases of watermelon leaves in the southeastern United States as well as a step-by-step guide to spraying. Continue reading

AgriLife Research cotton pathologist pursues a mystery

by Steve Byrnes, Texas A&M AgriLife

Dr. Terry Wheeler and her colleagues are embroiled in a mystery.

Wheeler, a Texas A&M AgriLife Research plant pathologist at Lubbock, and her cohorts Dr. Jason Woodward, Texas A&M AgriLife Extension Service plant pathologist at Lubbock, and Dr. Tom Isakeit, AgriLife Extension plant pathologist, College Station, have been getting calls from cotton growers across the Southern Rolling Plains and High Plains about a problem thought to have been resolved 40 years ago. Continue reading

Spotting and managing target spot

To hear first-hand from an expert about how to manage target spot and some results of research to help, tune in next Monday afternoon at 3 PM for Dr. Austin Hagan’s webinar on target spot. Click here to register.

From an article by Tyson Raper, University of Tennessee, in Cotton Grower

As the cotton specialist for the state of Tennessee, I am constantly on the lookout for potential issues that may impact Mid-South cotton production. Over the past several years, I have occasionally observed several “target spots,” or Corynespora leaf spots, on the lower leaves of rank cotton plants. Although the number of spots and number of affected leaves are typically low, many growers have asked if the disease might be able to cause the 200-400/lb lint per acre yield penalties reported along the Gulf coast. Continue reading

Tune in February 27 to learn how to manage target spot

In a webinar on Monday, February 27, at 3 PM Eastern, Austin Hagan, professor and extension plant pathologist at Auburn University, will discuss ways to recognize target spot in your field as well as management techniques to lower the risk.

Target spot, which is caused by the fungus Corynespora cassiicola, is an emerging disease in cotton in the Lower and Mid-South in the U.S. Phylogenetically, C. cassiicola isolates collected from cotton across the Lower South are distinct from those collected from other crops, particularly vegetables. This suggests that C. cassiicola isolates from cotton are either a recent introduction to the U.S. or has arisen from a mutation. Rainfall patterns along with variety selection and management inputs relating to yield potential influence the target spot risk in cotton. Greatest target spot-attributed defoliation and subsequent yield losses, which may exceed 300 pounds of lint per acre, have been recorded for an intensively managed, susceptible variety having a yield potential above 2.5 to 3 bales per acre. Continue reading

Resistant cotton varieties are best way to control bacterial blight

In Southwest Farm Press

Bacterial blight is like that really bad case of the flu you had one time years ago: It doesn’t happen often — but you never forgot it. In cotton, it can be just that bad.

It is an opportunistic plant disease in cotton, says Jason Woodward, Texas A&M AgriLife Extension pathologist at Lubbock. “The pathogen has been reported in every country where cotton is grown,” he said at the Red River Crops Conference at Childress, Texas. Continue reading

Warm winter temperatures spark fears of potential plant diseases

by Clint Thompson, University of Georgia

A La Nina weather pattern is providing warmer winter temperatures for Georgia residents, sparking farmers’ concerns about potential plant diseases at the start of production season in early spring.

University of Georgia Cooperative Extension plant pathologist Bob Kemerait said that farmers rely on extreme cold and freezing temperatures during the winter for a break from one growing season to the next. Right now, that isn’t happening. Continue reading