Nangle E.J.,Chicago District Golf Association |
Gardner D.S.,Dep. of Horticulture and Crop Science |
Metzger J.D.,Dep. of Horticulture and Crop Science |
Rodriguez-Saona L.,Dep. of Food Science and Technology |
And 3 more authors.
Agronomy Journal | Year: 2015
Pigments and phenolics that absorb ultraviolet light (UV) are involved in the protection of the photosynthetic apparatus during periods of high ultraviolet-B (UV-B) radiation and can be of benefit to turfgrasses. This study initiated in October 2010 and repeated in March 2011 aimed to characterize protective pigment responses to elevated UV-B in cool-season turfgrass. Tall fescue (Festuca arundinacea Schreb.), perennial ryegrass (Lolium perenne L.), and creeping bentgrass (Agrostis stolonifera L.) cultivars L93 and Penncross were tested. Turfgrass pigment responses were measured over a 1-wk period during which they were subjected to 16 kJ m-2 d-1 of UV-B in growth chambers. Photoperiod was 14 h and plants were subjected to 26.2 mol m-2 d-1 photosynthetically active radiation (PAR) at 20º C day and 17°C night. Turfgrass samples were collected at Day 0, 1, 3, 5, and 7. Measurements included chlorophyll uorescence, chlorophyll pigmentation, and avonoid, phenolic, anthocyanins, and carot-enoid concentrations. Chlorophyll uorescence increased and chlorophyll quantities decreased signi cantly (P < 0.05) in UV-B conditions compared to control. All species had signi cantly (P < 0.05) higher quantities of total phenolics and avonoids at the top of the tissue canopy relative to roots and shoot tissue near the soil surface. Anthocyanins were only found in creeping bentgrass L93. Carotenoids, zeaxanthin, and β-carotene declined in the UV-B treatment for both creeping bentgrass L-93 and Penncross a er 7 d, but did not decrease for perennial ryegrass or tall fescue. Carotenoids may play a greater role in UV-B tolerance than anthocyanins in cool-season turfgrasses due to their ubiquitous presence. © 2015 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved.
Griess J.K.,Dep. of Agronomy and Horticulture |
Mason S.C.,Dep. of Agronomy and Horticulture |
Jackson D.S.,Dep. of Food Science and Technology |
Galusha T.D.,Dep. of Agronomy and Horticulture |
And 2 more authors.
Crop Science | Year: 2010
Few studies have examined grain quality of food-grade sorghum hybrids. The objective of this study was to determine the effects of environment and hybrid on grain quality of commercially available food-grade sorghums. A randomized complete block experiment with three replications was planted in 12 environments, which included the 2004 and 2005 growing seasons and irrigated and dryland water regimes in eastern, central, and west central Nebraska and a dryland low-N environment in eastern Nebraska. Environment accounted for 5 to 140 times greater variation in measured parameters than hybrid, and the hybrid x environment interaction accounted for less than 2% of the total variation. Grain yield and kernel mass varied, with low yields of 1.4 Mg ha-1 and kernels weighing 9.5 g 1000 kernels-1 in the low-N 2004 environment, high grain yields of 10.5 Mg ha-1 under irrigated conditions in central Nebraska in 2005, and kernels weighing 27.8 g 1000 kernels-1 in the eastern Nebraska dryland 2005 environment. Harder grain was produced in 2005 than in 2004, with the west central and central 2005 environments having the lowest tangential abrasive dehulling device (TADD) removals of 14%. Non-food-grade hybrids produced higher grain yields and kernel mass than food-grade hybrids. Grain hardness was greater for nonfood-grade and medium maturity hybrids when environmental means were lower (i.e., softer) but showed little or no difference in hardness when environmental means were high. Nebraska production environments have the capability to produce high quality food-grade sorghums for specific food uses to benefit both the producer and the food processor. © Crop Science Society of America.