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Simple Summary: Production of small ruminants, specifically hair sheep, has increased in recent years and has resulted in an increased presence of hair sheep in feedlots for finishing. In 2017, the United States banned the use of antibiotic growth promoters. This ban has resulted in an interest in non-medicated feed additives, such as yeast, to aid in growth promotion. While hair lambs tend to take longer to reach an adequate finishing weight, the utilization of a yeast fermentation product may aid as a natural growth promoter in the feedlot. Additionally, interest in grass-based finishing systems has grown, but there are limited data on using stored cool-season forages as the base of the diet. Based on the results of this experiment, the inclusion of a yeast fermentation product can improve the feedlot performance and carcass texture of hair lambs in a feedlot with an annual ryegrass-hay-based diet. Hair sheep production has increased in recent years, which has resulted in an increased presence in feedlots. Additionally, grass-based finishing systems for ruminant animal production have increased. Data are limited for finishing hair lambs on diets based on cool-season hay. The objective was to evaluate a Saccharomyces cerevisiae fermentation product (SCFP) on the feedlot performance and carcass characteristics of Katahdin lambs offered an annual ryegrass (Lolium multiflorum)-hay-based diet. Twenty-four Katahdin lambs (21.5 ± 2.5 kg BW) were assigned to either the control (CON) or the yeast-supplemented group (SCFP) in a completely randomized design. Lambs were offered a 14% crude protein total mixed ration diet based on annual ryegrass hay. The SCFP group also received the yeast supplement in their diet. Lambs in the SCFP group had a higher final body weight (p < 0.01) and ADG (p = 0.01). Less maximum and total energy were required to cut SCFP lamb meat compared to CON lamb meat (p < 0.03). Results from this study indicated that SCFP supplementation may prove to be beneficial in hair lamb finishing diets. Future research will need to specifically evaluate the use of these products in hair lambs with a larger sample size. [ABSTRACT FROM AUTHOR]

Many winter stresses affect the ability of a perennial grass to overwinter in cold, temperate climates. Freezing tolerance is one of the major component traits affecting winterhardiness. Although effective freezing tolerance assessment procedures have long been available for perennial ryegrass ( Lolium perenne L.), no work has been done to characterize plant collections in the United States that may possess novel variation for freezing tolerance and winterhardiness. In this study, 21 accessions sampled from a larger set of 300 accessions with known winterhardiness and 3 check varieties were subjected to environmentally-controlled, low temperature acclimation, followed by controlled freezing using a programmable laboratory freezer. Eight freezing treatments from −2 to −16°C were used to determine survival across the known spectrum of freezing tolerance in perennial ryegrass. LT50 values were estimated based on whole plant survival, as well as tiller survival at each of the temperature treatments in the evaluation. LT50 values for the accessions and checks ranged from −10.31 to −13.95°C, with 3 accessions possessing significantly greater freezing tolerance than the most freeze-tolerant check, ‘NK200’. LT50 values were well correlated with winterhardiness in St. Paul during the winters of 2004–2005 and 2005–2006. Lower LT50 values in this experiment were associated with greater spring growth following the stressful winter of 2004–2005 and upright growth habit. The lack of negative biological association between freezing tolerance and turf quality components indicates that freezing tolerance testing could be a useful tool in breeding and selection with landrace germplasm. [ABSTRACT FROM AUTHOR]

Gray leaf spot caused by Magnaporthe oryzae is a serious disease of perennial ryegrass (Lolium perenne) turf in golf course fairways in the United States and Japan. Genetic relationships among M. oryzae isolates from perennial ryegrass (prg) isolates within and between the two countries were examined using the repetitive DNA elements MGR586, Pot2, and MAGGY as DNA fingerprinting probes. In all, 82 isolates of M. oryzae, including 57 prg isolates from the United States collected from 1995 to 2001, 1 annual ryegrass (Lolium multiflorum) isolate from the United States collected in 1972, and 24 prg isolates from Japan collected from 1996 to 1999 were analyzed in this study. Hybridization with the MGR586 probe resulted in approximately 30 DNA fragments in 75 isolates (designated major MGR586 group) and less than 15 fragments in the remaining 7 isolates (designated minor MGR586 group). Both groups were represented among the 24 isolates from Japan. All isolates from the United States, with the exception of one isolate from Maryland, belonged to the major MGR586 group. Some isolates from Japan exhibited MGR586 fingerprints that were identical to several isolates collected in Pennsylvania. Similarly, fingerprinting analysis with the Pot2 probe also indicated the presence of two distinct groups: isolates in the major MGR586 group showed fingerprinting profiles comprising 20 to 25 bands, whereas the isolates in the minor MGR586 group had less than 10 fragments. When MAGGY was used as a probe, two distinct fingerprint types, one exhibiting more than 30 hybridizing bands (type I) and the other with only 2 to 4 bands (type II), were identified. Although isolates of both types were present in the major MGR586 group, only the type II isolates were identified in the minor MGR586 group. The parsimony tree obtained from combined MGR586 and Pot2 data showed that 71 of the 82 isolates belonged to a single lineage, 5 isolates formed four different lineages, and the remaining 6 (from Japan) formed a separate lineage. This study indicates that the predominant groups of M. oryzae associated with the recent outbreaks of gray leaf spot in Japan and the United States belong to the same genetic lineage. [ABSTRACT FROM AUTHOR]

Bermudagrass [Cynodon dactylon (L.) Pers x C. transvaalensis Burtt-Davy] greens across the southern United States are normally overseeded in the fall to provide a uniform green playing surface and tolerance to wear during winter bermudagrass dormancy. The spring transition from overseed grass back to bermudagrass is a major problem associated with overseeding because there can be a decline in putting green quality and playability. There have been recommendations, but relatively few published reports, on the effect of treatments associated with seedbed preparation and overseeding on bermudagrass spring transition. The objective of this 2-year study was to determine if spring transition of an overseeded 'Tifgreen' bermudagrass green was influenced by fall-applied scalping level, chemical, and seed rate treatments. Treatment factors and levels were designed to reflect the range of practices used by golf course superintendents in the region at the time of the study. The green was located in the Palm Springs, Calif. area, which has relatively mild winters and a low desert, southern Calif. climate. The first year of the study was from September 1996 to July 1997 and the second year was from September 1997 to July 1998. Scalping level treatments included a moderate and severe verticut and scalp; chemical treatments included a check, trinexapac-ethyl at two rates, and diquat; and seed rate treatments included a high and low rate of a mixture of 'Seville' perennial ryegrass (Lolium perenne L.) and 'Sabre' rough bluegrass (Poa trivialis L.). The plot was maintained under golf course conditions and a traffic simulator was used to simulate golfer traffic. Visual ratings of percent green bermudagrass coverage were taken every 3 weeks from 20 Feb. 1997 to 29 July 1997 and from 11 Nov. 1997 to 22 July 1998. Visual turfgrass quality ratings were taken during the second year of the study. Results showed that spring transition was not influenced by fall-applied... [ABSTRACT FROM AUTHOR]

Italian ryegrass (Lolium perenne ssp. multiflorum (Lam) Husnot) is a troublesome weed species in wheat (Triticum aestivum) production in the United States, severely affecting grain yields. Spatial mapping of ryegrass infestation in wheat fields and early prediction of its impact on yield can assist management decision making. In this study, unmanned aerial systems (UAS)-based red, green and blue (RGB) imageries acquired at an early wheat growth stage in two different experimental sites were used for developing predictive models. Deep neural networks (DNNs) coupled with an extensive feature selection method were used to detect ryegrass in wheat and estimate ryegrass canopy coverage. Predictive models were developed by regressing early-season ryegrass canopy coverage (%) with end-of-season (at wheat maturity) biomass and seed yield of ryegrass, as well as biomass and grain yield reduction (%) of wheat. Italian ryegrass was detected with high accuracy (precision = 95.44 ± 4.27%, recall = 95.48 ± 5.05%, F-score = 95.56 ± 4.11%) using the best model which included four features: hue, saturation, excess green index, and visible atmospheric resistant index. End-of-season ryegrass biomass was predicted with high accuracy (R2 = 0.87), whereas the other variables had moderate to high accuracy levels (R2 values of 0.74 for ryegrass seed yield, 0.73 for wheat biomass reduction, and 0.69 for wheat grain yield reduction). The methodology demonstrated in the current study shows great potential for mapping and quantifying ryegrass infestation and predicting its competitive response in wheat, allowing for timely management decisions. [ABSTRACT FROM AUTHOR]

The article focuses on Wisconsin farmer Peter Pitts and his festulolium ryegrass. It cites how Pitts introduced his ryegrass variety to U.S. Dairy Forage Research Center Agricultural Research Service (ARS) geneticist Michael Casler. Pitts received a U.S. Department of Agriculture (USDA) small business grant to determine the superiority of his ryegrass variety with the assistance of Pure-Seed Testing Inc. of Hubbard, Oregon.

Focuses on a report by Lyons and Schwartz, which suggests that rare plant species contribute to the resistance of ecological communities to invasion. Series of experiments in a California grassland ecosystem; Susceptibility to successful invasion by an exotic ryegrass.