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Root allocation and distribution patterns can influence forage yield during periods of moisture or nitrogen stress, as deep-rooted species access water and nutrients found deeper in the soil profile. In a greenhouse study, we examined rooting characteristics to a depth of 50 cm for 21 cool-season forage species (9 grasses, 6 legumes, and 6 forbs) exposed to drought and low N conditions. The goal of this research was to compare root distribution under uniform growing conditions for common grass, legume and non-leguminous forb species found in humid-temperate pastures of the northeast United States. Nitrogen or water stressed grasses generally had greater root biomass and a greater proportion of roots in the 30 to 40 cm soil layer than did stressed legumes or forbs. Low N significantly reduced root weight, but to a lesser extent than the decrease in shoot weight, resulting in an increase in root/shoot ratio. Drought stress reduced shoot weight but had no effect on root weight, also resulting in a greater root/shoot ratio. Drought stress also increased the proportion of deep roots compared with controls, whereas, N stress did not. Comparisons with previously published field studies suggested that information from container-grown plants could provide insights into field results, and also suggested that inherent species differences in root distribution could explain some, but not all, rooting patterns observed in multi-species forage mixtures. doi: 10.2135/cropsci2009.08.0461

Chicory (Cichorium intybus L.), a deep-rooted forb, has potential for inclusion in pasture mixtures because of its reported drought tolerance and high productivity during summer months. This study examined how adding chicory to pasture mixtures affected forage yield, root growth, and soil moisture extraction under drought. The experiment was planted in August 2002. Movable rainout shelters were used to control water application in the field. Adding chicory to orchardgrass (Dactylis glomerata L.)-white clover (Trifolium repens L.) or perennial ryegrass (Lolium perenne L.)--white clover mixtures increased drought tolerance in 2003 when chicory constituted 24 to 39% of harvested forage biomass. Chicory mortality was high, decreasing from 39% of harvested forage yield under drought stress in early summer 2003 to 9% in late summer 2004. Improved yield under drought stress was not observed in 2004 when chicory constituted only 9 to 16% of the mixture. The three-species mixtures in 2003 had greater root counts than the two-species mixtures at soil depths below about 70 cm under well-watered conditions, but a greater proliferation of roots at depths below 70 cm was observed for the two-species mixture under drought stress. Both mixtures appeared capable of nighttime transfer of soil water from deep to shallow soil layers, thereby improving water availability to shallow roots. However, improved drought tolerance of the three-species mixture was probably related to improved water use efficiency rather than to greater access to and extraction of deep soil moisture.

Abstract: To gain insights into the structure and function of the wheat (Triticum aestivum L.) genomes, we identified 278 ESTs related to abiotic stress (cold, heat, drought, salinity, and aluminum) [...]

Improved cuitivars of narrow leaf plantain (Plantago lanceolata L.) have received increasing attention as possible pasture species for the northeastern USA because of their productivity during drought and high nutritive value. However, the cultivars currently available do not have sufficient freezing tolerance to survive northeastern U.S. winters. This experiment examined the relationship between shout growth rate and root:shoot partitioning during cold-hardening and the freezing tolerance of 'Lancelot' and 'Tonic' plantain compared with 'PG700', an experimental line collected from the eastern USA. I hypothesized that PG700 would exhibit reduced shoot structural growth and increased carbohydrate storage in roots during cold-hardening, resulting in increased freezing tolerance and survival. In growth chamber experiments, seedlings were cold hardened for 21 d and then frozen at -12°C for 3 h. Survival was evaluated after a 21-d recovery period. The experiment was conducted twice. Survival was greatest for PG700 (58%), followed by Lancelot (33%) and Tonic (18%) (P < 0.01). When combined across cuitivars, survival was 59% in Trial 1 compared with 11% in Trial 2 (P < 0.01). None of the measured parameters including overall root and shoot growth or relative partitioning between roots and shoots were related to cultivar differences in freezing tolerance. Reduced survival in Trial 2 was accompanied by high nitrogen uptake and vigorous shoot relative to root growth during the cold-hardening period. Thus, reduced shoot growth was accompanied by increased freezing tolerance when differences in survival were induced by environmental effects but was not related to genetic differences in survival., IMPROVED CULTIVARS of narrow-leaf plantain have received increasing attention as possible forage and pasture species for the northeastern USA because of their reportedly high productivity during periods of drought and [...]

Introduced (nonnative) species account for nearly all of the forage grasses used in northeastern USA forage systems. We evaluated accessions of the native cool-season species, Eastern bottlebrush grass (Elymus hystrix var. hystrix L.), from the northeastern USA for yield, persistence, plant morphological traits, and nutritive value. Thirteen accessions and one commercial ecotype of bottlebrush grass were transplanted into single-row field plots in late summer of 2000 at Beltsville, MD, Rock Springs, PA, and Big Flats, NY. Two orchardgrass (Dactylis glomerata L.) cultivars were included for reference. Yield, persistence, morphology (leaf width, length, mass, area, and tillers per plant), and nutritive value data were collected during 2001 and 2002. Bottlebrush grass was eliminated by the bluegrass billbug (Sphenophorus parvulus Gyllenhal) at Rock Springs in spring of 2001. At Big Flats and Beltsville, the bottlebrush grass accessions produced as much dry matter per plant as the commercial ecotype. Orchardgrass yielded four times as much dry matter as the mean of all bottlebrush grass entries (102 g vs. 26 g per plant averaged for years and locations). The low productivity of bottlebrush grass resulted from reduced tillering especially during regrowth. There was very little regrowth of bottlebrush grass during late summer in all environments. Survival of bottlebrush grass was 36% during 3 yr vs. 84% for orchardgrass. Differences in nutritive value among accessions were due mainly to differences in leaf-to-stem mass ratio. Eastern bottlebrush grass has limited potential for use as a forage grass in the northeastern USA., THE COMMONLY USED cool-season forage grasses in the northeastern USA are introduced species. The native grasses most often used in northeastern forage systems are warm-season perennials such as switchgrass (Panicum [...]

Pasture productivity under harsh environments can be increased by planting more drought-resistant species or by increasing species diversity. This research was conducted under two large (10.2 x 26.8 m) rainout shelters combined with a drip irrigation system to provide deficit, normal, and excessive moisture conditions. A two-species mixture containing the relatively drought-tolerant species, orchardgrass (Dactylis glomerata L.) and red clover (Trifolium pretense L.) and two five-species mixtures were compared with a mixture containing the drought-sensitive species, white clover (Trifolium repens L.) and Kentucky bluegrass (Poa pratensis L.), which are the predominant species in northeastern USA pastures. Plots were clipped from mid-May to early October in 2000 and 2001 on a schedule that mimicked management-intensive grazing practices. The five-species mixture containing chicory (Cichorium intybus L.), orchardgrass, Kentucky bluegrass, perennial ryegrass (Lolium perenne L.), and white clover had the greatest dry matter yield at all moisture levels. Yield in that mixture increased 89% in the dry, 61% in the normal, and 43% (by weight) in the wet treatments compared with the white clover/ Kentucky bluegrass mixture. Increased yield was primarily due to the robust growth of chicory which dominated the mixture, accounting for 71% of harvested biomass by the fall of 2001. In addition, white clover growing in the mixture with chicory had improved leaf water relations and greater relative growth rates than white clover growing in the two-species mixture. Including the functional attribute of a deep-rooted forb appeared to be more important than species richness, per se, in improving forage yield., A PRIMARY GOAL of grazingland managers in the northeastern USA is to improve forage production during summer months when heat and moisture stress limit growth of cool-season forages. Although temperate [...]

Interest in native plant species for conservation and production has increased because of new federal policies. We evaluated accessions of the native cool-season grass Virginia wildrye (Elymus virginicus L.) from the northeastern USA for nutritive value and its association with plant morphological traits. Thirteen accessions, one cultivar (Omaha), and one commercial ecotype of Elymus were transplanted into single-row field plots in late summer of 2000 at Beltsville, MD, Rock Springs, PA, and Big Flats, NY. Two orchardgrass (Dactylis glomerata L.) cultivars were included. Primary growth was harvested in April (Beltsville) or May (Rock Springs and Big Flats) of 2001 and 2002 and analyzed for neutral detergent fiber (NDF), crude protein (CP), and digestible NDF (dNDF). Nutritive value measures were related to plant morphological attributes [leaf width, length, area, and leaf-to-stem mass ratio (LSR)]. Virginia wildrye accessions differed (P < 0.01) in nutritive value and often had lower NDF and higher CP and dNDF than the commercial ecotype, Omaha cultivar, and orchardgrass. The LSR accounted for most of the variation in nutritive value. Orchardgrass was more mature at harvest than Elymus entries and thus lower in nutritive value. Neutral detergent fiber was negatively correlated with LSR (r = -0.26 to -0.74, P < 0.05), whereas CP and dNDF were positively correlated (r = 0.36 to 0.80 for CP and 0.44 to 0.74 for dNDF, P < 0.05). Neutral detergent fiber was also positively correlated (r 0.27 to 0.86, P < 0.05) with leaf length. Virginia wildrye is comparable to other cool-season grasses in nutritive value., MOST FORAGE GRASSES grown in the northeastern USA are introduced species such as orchardgrass, bluegrass (Poa spp.), or tall fescue (Festuca arundinacea Schreb.). Native warm-season perennials, such as switch-grass (Panicum [...]

Most forage grasses grown in the northeastern USA are introduced species. Interest in native plant species for conservation and production has increased because of new federal policies. We evaluated northeastern accessions of the native cool-season grass Virginia wildrye (Elymus virginicus L.) for yield, persistence, and plant morphological traits. Thirteen accessions, one cultivar (Omaha), and one commercial ecotype of Elymus were transplanted into single-row field plots in late summer of 2000 at Beltsville, MD, Rock Springs, PA, and Big Flats, NY. Two orchardgrass (Dactylis glomerata L.) cultivars were the checks. Yield and morphology (leaf width, length, mass, area, and tillers per plant) data were collected during 2001 and 2002. The Elymus accessions produced as much dry matter (28-57 g per plant) as the cultivar and commercial ecotype. Orchardgrass yielded more than twice as much dry matter than the mean of all Elymus entries (94 vs. 34 g per plant averaged fur years and locations). The difference in productivity was related to reduced tillering in Elymus especially during regrowth. Yield per plant was strongly correlated (r = 0.62-0.81, P < 0.01) with the number of tillers per plant. Differences in productivity were also reflected in leaf blade traits, with Elymus having a lower leaf area and mass than orchardgrass. Leaf traits were positively correlated (r = 0.35-0.56, P < 0.05) with plant yield. Some northeastern Elymus accessions would probably perform as well as the commercial sources of Elymus in conservation plantings., INTRODUCED SPECIES, such as orchardgrass, account for nearly all of the highly productive forage grasses grown in the northeastern USA. The most frequently grown native grasses in forage systems arc [...]

Non-alcoholic fatty liver disease and alcoholic liver disease, the two most prevalent liver diseases worldwide, share a common pathology but have largely been considered disparate diseases. Liver diseases are widely underestimated, but their prevalence is increasing worldwide. The Western diet (high-fat, high-sugar) and binge drinking (rapid consumption of alcohol in a short period of time) are two highly prevalent features of standard life in the United States, and both are linked to the development and progression of liver disease. Yet, few studies have been conducted to elucidate their potential interactions. Data shows binge drinking is on the rise in several age groups, and poor dietary trends continue to be prevalent. This review serves to summarize the sparse findings on the hepatic consequences of the combination of binge drinking and consuming a Western diet, while also drawing conclusions on potential future impacts. The data suggest the potential for a looming liver disease epidemic, indicating that more research on its progression as well as its prevention is needed on this critical topic. [ABSTRACT FROM AUTHOR]

`Ceres Tonic' and `Grasslands Lancelot' narrow-leaf plantain (Plantago lanceolata L.) and `Grasslands Puna' chicory (Cichorium intybus L.) have received considerable interest as potential new forages for the northeastern USA because of their reported drought tolerance and high forage quality. However, all three cultivars were developed under New Zealand conditions and may not have sufficient winter hardiness to survive northeastern USA winters. Growth chamber and field studies were conducted to determine the freezing tolerance and winter survival of these new forages under well-watered and drought conditions. Winter survival of chicory in the field ranged from 73% of marked plants in the wet treatment to 93% following summer drought. Likewise, winter survival of plantain in the field increased from 3% in the wet treatment to 41% in the dry treatment. Survival of Lancelot plantain in the growth chamber increased from 4% in the well-watered to 16% in the drought treatment. However, survival of Tonic plantain and Puna chicory in the growth chamber was not affected by drought. Chicory survival was greater than survival of plantain in both controlled and field environments. Puna chicory appears to have sufficient winter hardiness to survive winters in the northeastern United States. Although Lancelot had slightly greater survival than Tonic, neither plantain cultivar had sufficient freezing tolerance to be recommended for use in the northeastern USA. Improved cultivars will need to be developed from populations that have evolved under more severe winter conditions before plantain can become a viable forage for most of this region., IMPROVED CULTIVARS of forage chicory and narrow-leaf plantain have received increasing attention as possible forage and pasture species for the northeastern United States because of their reported high productivity during [...]