Closeup of the head to Solenopsis geminata (fire ant)

Joint Evolution of Asexuality and Queen Number in an Ant

A recent paper in Current Biology by DeWayne Shoemaker and colleagues from the University of Georgia describes a socially polymorphic population of the tropical fire ant, Solenopsis geminata, in which multi-queen colonies produce queens asexually but produce workers sexually via matings with males from the sexually reproducing single-queen social form. Two distinct asexual lineages from multi-queen colonies likely originated from the same sexual single-queen population. Multiple asexual/polygyne genomes are transmitted undiluted in this system, but sterile workers produced with sperm from a sexually-reproducing/monogyne population are necessary for the persistence of these lineages. The intersection of social polymorphism, facultative asexuality, and genetic caste determination marks this population of S. geminata as an embodiment of the diversity of ant reproductive systems and suggests previously…

Tomatoes and peppers in various sizes and colors on display

UTIA Scientists Publish Paper on Role of Citizen Science in Addressing Agricultural Challenges

Dr. Sean Ryan, a postdoctoral researcher in the EPP Department, Dr. DeWayne Shoemaker, and an international team of more than three dozen researchers published a paper highlighting the potential of citizen science to address pressing research challenges in agriculture and food systems. One key to capitalizing on such efforts, the researchers find, may be to build stronger ties between citizen science and agricultural extension efforts. A press article summarizing the article is here and a free copy (open access) of the original paper can be downloaded from the journal web site.

A comparison of the front and backside of a leaf that is infected by grapevine rust

Be on the Lookout for Grapevine Leaf Rust in Tennessee

Dr. Zach Hansen published an article in the November 2018 National Plant Diagnostic Network newsletter. Grapevine leaf rust was observed for the first time in Tennessee in September 2018. The disease was found on grape seedlings at large box stores in several counties in middle and east Tennessee. Dr. Hansen suggests that growers, industry professionals, diagnosticians and extension personnel should be aware of the disease and should be on the lookout for it. For the full article, click here.

David checks behind a cows ears for ticks

Tennessee Tick Survey by Dr. Trout Fryxell and David Theuret

A tick survey study in Tennessee by Dr. Trout Fryxell and graduate student David Theuret highlighted in Entomology Today. The study revealed that one in six cattle and at livestock monitoring locations in all regions of the Tennessee have ticks. For more details, please see summary article Tick Surveillance Project Offers Model for Monitoring Livestock. The original article can be found here.

Close-up of a fire ant; note the large head and mandibles

Recent Article: Sociometry of Solenopsis Geminata Reveals Variation in Colony-Level Phenotypes in Fire Ants

Abstract: In social insects, natural selection operates at the level of the colony, rather than the individual, but our understanding of how colony-level phenotypes arise and vary between species is lacking. Here, we test how colony-level phenotypes vary within the fire ants by measuring the composition of colonies of the tropical fire ant, Solenopsis geminata, over a wide range of sizes at multiple times throughout the year. Similar to the well-studied fire ant species S. invicta, we find that S. geminata colony composition varies strongly with colony size, such that as colonies grow they produce increasingly large workers as well as queens and males. However, major production increases more rapidly with colony size in S. geminata than in S. invicta,…