Tall fescue salt rooting bench study
Salt is a major environmental stressor that can damage plants and inhibit their growth. Turfgrasses are particularly sensitive to salt, as they have a high water content and a relatively shallow root system. When salt levels in the soil or water become
too high, turfgrasses can experience several problems, including: wilting; stunted growth; chlorosis (yellowing of leaves); and death.
At Pure-Seed Testing, we are conducting salinity resistance screening through a salt bench that holds sand tubes 3 feet (91 centimeters) long and drips salt water onto the plant over three months. The sand in these tubes provides adequate draining of
the salt water. The total sodium chloride concentration in the water is 20 ppt. We then increase the salt throughout the study to the point where some varieties die completely, and others remain 40% to 60% green. We rate each plant every two weeks
until all the varieties have died. In this study, tall fescue varieties are being tested.
Salt tolerance in turf-type tall fescues (TTTF) continues to be extremely important as temperatures continue to rise and climates become drier. In Southern California, sod farms have saline water for irrigation. Historically, they have not been able to
establish TTTF in the hot and dry summer due to their poor water quality. With PST-improved salt-tolerant varieties, they have been able to establish and survive, all while using less inputs. As we continue to see the world around us change, at PST
and Pure Seed we strive to research and develop more sustainable turfgrasses that reduce required inputs and meet the needs of professionals around the world.
— McKayla Fricker (firstname.lastname@example.org), communications director, Pure Seed, Canby, Ore.
Tuber production and viability of yellow nutsedge in response to postemergence herbicides
Yellow nutsedge (Cyperus esculentus L.) is one of the most problematic turfgrass weeds due to its fast growth rate and high tuber production. Effective long-term control relies on translocation of systemic herbicides to underground tubers. Research was
conducted at the Athens Turfgrass Research and Education Center in Athens, Ga., in 2022 to evaluate postemergence herbicides on tuber production and viability.
Tubers were planted into 33.8-ounce (1-liter) pots containing a 2:1 mixture of Cecil clay loam soil and Wakulla sand. Plants matured in the greenhouse for six weeks before initial herbicide treatments were applied on Jan. 13, with sequential applications
made Feb. 4. Pots were arranged in a randomized complete block design with five replications. Treatments were pyrimisulfan (Vexis, PBI-Gordon) at 1 ounce active ingredient per acre (73 grams active ingredient per hectare) once or 0.7 ounces active
ingredient per acre (49 grams active ingredient per hectare) twice; imazosulfuron (Celero, Nufarm) at 10.5 ounces active ingredient per acre (736 grams active ingredient per hectare) once or 6 ounces active ingredient per acre (420 grams active ingredient
per hectare) twice; sulfentrazone + carfentrazone (Dismiss NXT, FMC) at 3 ounces active ingredient per acre (220 grams active ingredient per hectare) once or 2 ounces active ingredient per acre (141 grams active ingredient per hectare) twice; and
halosulfuron (Sedgehammer+, Gowan) at 62 pounds active ingredient per acre (70 kilograms active ingredient per hectare) once or 31 pounds active ingredient per acre (35 kilograms active ingredient per hectare) twice. A nonionic surfactant was added
to Celero at 0.25% v/v. At 8 and 11 weeks after initial treatment (WAIT), shoot dry biomass (grams), tuber dry biomass (grams), tuber number and tuber viability (%) were measured.
Dismiss NXT exhibited the quickest phytotoxicity. Two applications of Celero resulted in the greatest reduction in tuber number (81%) and tuber weight (85%), while one application of Dismiss NXT resulted in the greatest reduction in shoot biomass (71%).
Viability of tubers that were recovered from each pot was reduced 48% to 70%, with the greatest reduction in response to Dismiss NXT. Although two applications of Vexis only resulted in tuber number and shoot biomass reductions of 66% and 38%, respectively,
tuber weight reduction was 80%.
— Julie Wang (ChihJulie.Wang@uga.edu), Erick Begitschke, Kevin Tucker and Gerald M. Henry, University of Georgia-Athens
Darrell J. Pehr (email@example.com) is GCM’s science editor.