University of Arkansas

About: University of Arkansas is a education organization based out in Fayetteville, Arkansas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 17225 authors who have published 33329 publications receiving 941102 citations. The organization is also known as: Arkansas & UA.

Sugarcane Aphid (Hemiptera: Aphididae): A New Pest on Sorghum in North America.

Abstract: In 2013, the sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), a new invasive pest of sorghum species in North America, was confirmed on sorghum in 4 states and 38 counties in the United States. In 2015, the aphid was reported on sorghum in 17 states and over 400 counties as well as all sorghum-producing regions in Mexico. Ability to overwinter on living annual and perennial hosts in southern sorghum-producing areas and wind-aided movement of alate aphids appear to be the main factors in its impressive geographic spread in North America. Morphological characteristics of the sugarcane aphid include dark tarsi, cornicles, and antennae, allowing easy differentiation from other aphids on the crop. Sugarcane aphid damages sorghum by removing sap and covering plants with honeydew, causing general plant decline and yield loss. Honeydew and sooty mold can disrupt harvesting. The aphid's high reproductive rate on susceptible sorghum hybrids has resulted in reports of yield loss ranging from 10% to greater than 50%. In response, a combination of research-based data and field observations has supported development of state extension identification, scouting, and treatment guides that aid in initiating insecticide applications to prevent yield losses. Highly efficacious insecticides have been identified and when complemented by weekly scouting and use of thresholds, economic loss by sugarcane aphid can be minimized. Some commercial sorghum hybrids are partially resistant to the aphid, and plant breeders have identified other lines with sugarcane aphid resistance. A very diverse community of predators and parasitoids of sugarcane aphid has been identified, and their value to limit sugarcane aphid population growth is under investigation.

Inheritance of a gene for resistance to tomato spotted wilt virus (TSWV) from Lycopersicon peruvianum Mill.

Abstract: Inheritance of resistance to tomato spotted wilt virus (TSWV) derived from the cultivar ‘Stevens’ was studied. Five TSWV isolates, which differ in geographic origin and elicit different symptoms on tomato, were used to screen the resistant parent plants. Enzyme-linked immunosorbent assay (ELISA) was used to distinguish healthy and infected plants. Two susceptible advanced breeding lines were crossed with four F4 plants of a ‘Stevens’ × ‘Rodade’ obtained from South Africa (SA). There were no differences in the progeny responses of the four SA parents to TSWV. The inheritance of TSWV resistance was found to be a single dominant gene. The SA, F1, and the backcrosses to the resistant parent were found to have eight out of 612 plants infected four months after the inoculations, which indicates a 98.7% penetrance of the resistance gene.