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This article identifies the quality themes of distance learning that arose from the learners' perspective as reflected in the literature. The paper reviews literature through the four themes of 1) Course design, 2) Interaction, 3) Learner support and 4) Technology Use. Key quality indicators in distance learning that appear repeatedly in research on students' point of view are also examined. It is argued that distance learning quality standards must first be focused on the students' perspective in order to develop comprehensive and efficient standards for evaluating distance learning. This review serves as a starting point for distance learning providers specifically and accreditation organizations generally to better inform current quality practices regarding distance learning environments in higher education.

Perennial groundcover (PGC) has promise as a scalable approach to generating natural resource benefits and sustainable biofuel feedstock while preserving the high yields of annual row crop production. Partnering row crops with temporally and spatially complementary low-growing, shallow-rooted perennials, such as Kentucky bluegrass (KBG) (Poa pratensis L.), is one example of an emerging PGC system. PGC's ecosystem benefits can only be fully realized if commercial-scale adoption occurs, which hinges on its economic feasibility. This paper utilizes an enterprise budget framework to detail and compare the expected cost and revenue of establishing and maintaining PGC in row crop systems with standard continuous corn (SCC) (Zea mays L.) production, including stover harvest, but excluding economic incentives for ecosystem services. Optimistic and pessimistic assumptions were used, along with Monte Carlo simulation, to characterize the uncertainty in results. In the optimistic stover market scenario, Year 1 net returns for PGC averaged USD 84/ac less than for SCC; Year 2+ net returns averaged USD 83/ac more, meaning that cost parity with SCC occurs by the second PGC system year. Without stover revenue, parity is achieved after five years. These results affirm that PGC's economic viability is critically impacted by a groundcover's lifespan, the yield parity with SCC, and the availability of a stover market. [ABSTRACT FROM AUTHOR]

Perennial groundcover (PGC) merges scalable soil and water conservation with high-yielding row crops, enhancing ecosystem services of annual grain crop production. However, ineffective groundcover suppression increases competition between the groundcover and row crop, reducing row crop grain yield. The objective of this study was to assess the effectiveness of three Kentucky bluegrass (KBG) groundcover suppression methods each at narrow and wide widths on maize (Zea mays L.) growth and development in evenly spaced PGC, compared to alternating PGC swards and a no-PGC conventional tillage control. Suppression methods for evenly spaced PGC included two different strip tillage implements, completing either shallow or deep soil fracture, for mechanical suppression and a banded sprayer for no-tillage chemical suppression. We measured weekly for maize plant height, phenological stage of development, reflected red:far-red (R:FR) ratio, early vegetative and final plant density, grain and stover yield, yield components of kernel rows ear−1, kernels row−1, kernels ear−1, ear length, kernel weight, grass frequency, and weed community. In 2020, maize grain yield in the alternating PGC swards (11.38 Mg ha−1) was similar to the control (12.78 Mg ha−1) and greater than in the evenly spaced groundcover (9.62 Mg ha−1). Maize grain yield was similar for systems in 2021 (7.41 Mg ha−1), due to drought and high coefficient of variation. Weed community was similar for systems in both years. A maize competition response was observed for both suppression widths across methods. Groundcover dormancy may be needed in conjunction with effective chemical and/or mechanical groundcover suppression to support maize production in PGC. [ABSTRACT FROM AUTHOR]

Perennial groundcover (PGC) has great potential to deliver ecosystem service benefits and control weeds in annual row crop systems. Inadequately suppressed PGC, however, acts as an early-season weed, causing a shade avoidance response (SAR) in maize (Zea mays L.) before the critical period for weed control (CPWC) even with resource abundance. The SAR results from a low red to far-red light shift, impairing early season plant growth and decreasing yield. A field study was conducted in Ames, IA, USA to assess application timing of groundcover suppression chemicals on maize growth and development. Two suppression chemical treatments (paraquat or paraquat + glufosinate) were each applied to "Midnight" Kentucky bluegrass (Poa pratensis L.) PGC once on the day of maize planting (DOP) or consecutive maize stages from VE to V6 in a randomized complete block design with unsuppressed groundcover control. Response variables included maize plant height, maize phenological development stage, reflected red:far-red (R:FR) ratio above the PGC canopy, early vegetative and final maize plant density, maize yield and components, and weed communities. Suppression increased reflected R:FR ratio from the groundcover immediately after application. Where suppression was applied at later stages, low R:FR ratio during early vegetative growth stages triggered a maize SAR and maize plant etiolation. Final maize plant height and yield were greater in PGC suppressed at earlier maize stages, although no suppression treatment provided adequate suppression duration. Paraquat + glufosinate more effectively suppressed groundcover overall and limited groundcover competition, producing 8% greater maize grain yield than paraquat alone in year 1, and 13% greater stover and 8% greater total aboveground biomass (TAB) in year 2. Weather conditions influenced chemical suppression efficacy in year 2, emphasizing the importance of identifying reliable chemical suppression to support grain yield from the day of maize planting. [ABSTRACT FROM AUTHOR]

Removal of crop residue poses negative consequences for soil health, nutrient leaching, and runoff. Perennial groundcovers (PGC) provide a method of maintaining soil health while allowing the sustainable intensification of maize (Zea mays L.) systems for biofuel production by providing groundcover for several years. However, previous studies have only evaluated a few varieties of PGC. We conducted a 2‐yr study to evaluate the compatibility of cool‐season turfgrass PGCs under maize. Maize was interplanted into 20 accessions of Kentucky bluegrass (Poa pratensis L.), Sandberg bluegrass (Poa secunda J. Presl), and red fescue (Festuca rubra L.) in a randomized complete block design in Boone, IA. Data on maize grain yield, maize grain quality, and ground coverage of PGC were collected. There were no differences in maize grain yield across species in 2017. In 2018, maize grain yield under red fescue was 1.0, 1.8, and 2.1 Mg ha–1 less than Kentucky bluegrass, Sandberg bluegrass, or the no‐grass control, respectively. Maize under red fescue produced 2.3, 4.8, and 3.9 g kg–1 more protein than Kentucky bluegrass, Sandberg bluegrass, and the no‐grass control, but produced 878 L ha–1 and 758 L ha–1 less ethanol than the no‐grass control and Sandberg bluegrass, respectively. In both years, Kentucky bluegrass groundcover declined approximately 22%, while Sandberg bluegrass groundcover remained below 10%. Red fescue maintained groundcover over 22% in 2017 and 34% in 2018. These results indicate that maize under Kentucky bluegrass and Sandberg bluegrass can perform similarly to conventional maize. Core Ideas: Perennial groundcovers can provide natural resource benefits in maize production.As species, Kentucky bluegrass and Sandberg bluegrass can be compatible with maize.Maize grown with certain accessions can maintain or increase grain yield.Differences were observed in Kentucky bluegrass and Sandberg bluegrass accessions. [ABSTRACT FROM AUTHOR]

Seed quality of maize (Zea mays L.) can be negatively impacted by a fall frost event. It is important for the seed industry to detect frost damage early and to make marketing decisions before the seed lots are conditioned for sale. This study compared several seed quality tests (standard germination [WG], accelerated aging [AA], saturated cold [SC], and soak tests) for their ability to quantify frost damage. Additionally, these tests were used to predict field emergence under poor and average to good field conditions. Two genotypes (B73 x IRF311 and Mo17 x IRF311) were harvested at three moisture contents (300-350, 400-450, and 500-550 g [H.sub.2]O [kg.sup.-1] fresh weight). An artificial frost treatment was applied to the seed and damage was determined by testing seed after approximately 0, 1.5, 3, 4.5, and 6 mo of storage. The artificial frost treatment significantly decreased viability and vigor of all the seed lots except Mo17 x IRF311 harvested at 300 to 350 g [H.sub.2]O [kg.sup.-1] fresh weight. As seeds matured, the damage associated with frost treatment decreased. Laboratory tests did not accurately predict field emergence of frost-damaged seed under poor field conditions; however, AA at 0 mo, SC at approximately 0, 1.5, and 3 mo, and soak at approximately 0, 1.5, and 3 mo had strong relationships to field emergence under average to good field conditions. These results indicate that frost damage in seed lots is quantifiable using the SC and soak tests during approximately the first 3 mo of storage and both tests accurately predict field emergence.

Pasturelands are inherently variable. It is this variability that makes sampling as well as characterizing an entire pasture difficult. Measurement of plant canopy reflectance with a ground-based radiometer offers an indirect, rapid, and noninvasive characterization of pasture productivity and composition. The objectives of this study were (i) to determine the relationships between easily collected canopy reflectance data and pasture biomass and species composition and (ii) to determine if the use of pasture reflectance data as a covariate improved mapping accuracy of biomass, percentage of grass cover, and percentage of legume cover across three sampling schemes in a central Iowa pasture. Reflectance values for wavebands most highly correlated with biomass, percentage of grass cover, and percentage of legume cover were used as covariates. Cokriging was compared with kriging as a method for estimating these parameters for unsampled sites. The use of canopy reflectance as a covariate improved prediction of grass and legume percentage of cover in all three sampling schemes studied. The prediction of above-ground biomass was not as consistent given that improvement with cokriging was observed with only one of the sampling schemes because of the low amount of spatial continuity of biomass values. An overall improvement in root mean square error (RMSE) for predicting values for unsampled sites was observed when cokriging was implemented. Use of rapid and indirect methods for quantifying pasture variability could provide useful and convenient information for more accurate characterization of time consuming parameters, such as pasture composition., SAMPLING IS THE researcher's best way to learn about a population. When a pasture is considered to be a population, the task is to determine where to sample and how [...]

Seed dormancy is a main factor limiting the use of eastern gamagrass (Tripsacum dactyloides L.) for forage and conservation purposes; however, there is little available information on the seed bank dynamics of eastern gamagrass plantings. Knowledge of the degree and rate of seed dormancy loss would improve decisions concerning eastern gamagrass plantings and provide a better understanding of the seed bank longevity for this species. In this study, cold, moist stratified seed or unstratified seed was planted at 2.5- and 5.0-cm depths on 16 Aug. 1999, 1 Nov. 1999, 14 April 2000, 15 May 2000, and 16 June 2000 for the first year of the study and 15 Aug. 2000, 31 Oct. 2000, 17 April 2001, 15 May 2001, and 15 June 2001 in the second year. Plants and seeds were retrieved at 3, 6, 9, and 12 mo after planting of 50 seeds for each seed treatment and planting depth combination. Intact seeds were germinated for 28 d and the viability of ungerminated seeds was determined with a tetrazolium test. Seed dormancy of both stratified and unstratified eastern gamagrass seed was lost mostly between mid-September and mid-November. No more than 12% dormant seed remained after mid-December and dormancy was completely lost by April and May. Seed dormancy in eastern gamagrass was substantially reduced with several weeks of soil temperatures below 15°C and adequate soil moisture., EASTERN GAMAGRASS is a warm-season, perennial, bunch grass found growing naturally from the northeastern and north central USA and south into Mexico, Central America, the Caribbean, and into Bolivia and [...]

The productivity of grasslands depends in part on their diversity of species and functional composition. Our objective was to examine the effects of three landscape positions (summit, backslope, and toeslope) and three stocking systems (continuous, rotational, and nongrazed) on species diversity and percentage of cover of grass, legume, and weed species functional types in southeastern Iowa pastures. Data were collected in 0.2-[m.sup.2] plots randomly distributed throughout each of four replicate pastures in spring and summer 2000 and 2001. Backslope landscape positions within pastures managed with either continuous or rotational stocking contained the greatest overall diversity of species. Across years, overall species richness under grazing averaged 4.8 on backslopes, 3.5 on summits, and 2.9 on toeslopes. Legume cover was greatest within the rotational stocking system, averaging 21% on backslopes, 10% on summits, and 3% on toeslopes across years. Cool-season grasses dominated summits and toeslopes, consisting of 88 to 94% of the cover. Weed species diversity and cover were greatest on backslopes within the continuous stocking system. Our results showed that rotational stocking had more desirable effects through greater legume cover and less weed cover on backslopes than continuous stocking. This research suggested that spatial components of pastures should be considered to optimize the production and quality of forage for grazing livestock., THE PRODUCTIVITY AND STABILITY of aboveground biomass in grassland ecosystems depends inpart on the functional composition and diversity of plant species. Recent experiments showed that species-rich grasslands have greater productivity [...]

Alfalfa (Medicago sativa L.) adapted to the midwestern USA typically becomes dormant in autumn to survive winter stress. Nondormant alfalfa germplasm produces higher biomass yield during autumn but usually dies during the winter. The objective of this study was to test the hypothesis that recurrent selection could decrease winter injury in nondormant alfalfa populations. Between 1997 and 2000, three cycles of selection were conducted at Ames, IA, in four nondormant cultivars (5939, GT13R+, CUF101, and Magna 8) by recurrently selecting the most vigorous plants in the spring following establishment. In May 2001, the original cultivars and the three cycles of selection (C0, C1, C2, and C3) of each cultivar were transplanted with six check cultivars in the field at Ames, IA, and West Lafayette, IN. Biomass yield was measured in September and November 2001 at both locations. In November 2001, half of the plants in each plot were removed and roots were analyzed for total sugar, starch, and protein concentrations. The remaining plants were scored for winter injury in April 2002. Strong negative linear trends were observed across cycles for both winter injury and autumn plant height. In contrast, forage biomass yields showed little change. Root total sugar concentration in November increased with cycle of selection, but root starch, protein, and amino acid concentrations remained constant. Little change was noted among cycles for forage nutritive value. Selection based solely on winter injury can improve winter hardiness of nondormant populations. A concomitant decrease in autumn plant height may not affect autumn yield., WINTER, AND ITS attendant stresses, represents one of the most limiting factors for growing alfalfa in the midwestern USA. The amount of winter injury a cultivar suffers is related in [...]

Landscape position affects legume establishment in pastures. We conducted this study to (i) determine the role of emergence and survival on establishment of legumes on summit and backslope positions and (ii) examine how competition, as influenced by sward-cutting height and N fertilization, affects legume emergence and survival across these positions. We no-till drilled a mixture composed of red clover (Trifolium pratense L.), alfalfa (Medicago sativa L.), and birds-foot trefoil (Lotus corniculatus L.) into an existing cool-season grass pasture at Rhodes, IA, in 1998 and 1999. Treatments consisted of landscape positions (summit and backslope), N fertilizer rates (0, 22, 44, and 89 kg [ha.sup.-1]), and sward heights (uncut, 5, and 13 cm). Landscape position did not affect legume emergence in swards cut at 5 and 13 cm. At those heights, emergence averaged 1041 and 831 seedlings [m.sup.-2]. In swards cut at 5 cm, 62 plants [m.sup.-2] survived on summits vs. 183 plants [m.sup.-2] on backslopes. Legume emergence and survival generally decreased as sward height and N fertilization increased but interactions with landscape position occurred. Addition of 89 kg [ha.sup.-1] N was required to reduce survival on backslopes to 39 plants [m.sup.-2], a density similar to that on summits. Our results show that seedling survival limits legume establishment on summit positions in pastures. Legume establishment is successful on backslopes because of less competition from grass. We recommend that legumes be seeded on backslope positions in pastures, N fertilizer not be applied, and grass competition be reduced before seeding legumes in pastures., LEGUMES improve the production and nutritional value of forage in cool-season grass pastures. Pastures composed of grasses and legumes produce more dry matter than grass-only pastures (Taylor and Allinson, 1983). [...]

A semihybrid variety development system could capture natural hybrid vigor found between alfalfa (Medicago sativa L.) populations. Medicago sativa subsp, sativa and subsp. falcata represent a heterotic pattern that could be used in a semihybrid breeding system to increase yields, but the forage quality of inter-subspecific crosses in relation to intra-subspecific crosses is unclear. The objective of this study was to compare forage quality of sativa x falcata crosses (SFC), sativa x sativa crosses (SSC), and falcata x falcata crosses (FFC). We used the standard forage quality measures of in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), crude protein (CP), leaf/stem ratio (LSR), hemicellulose, and cellulose to measure stem forage quality of inter- and intra-subspecific sativa and falcata crosses. Forage was sampled in October 1998 and May 1999 at Ames, IA, and May 1999 Nashua, IA. Sativa-falcata hybrids had slightly decreased stem forage quality compared with the expected quality based on the average of the intra-subspecies cross means. For most forage quality traits the decreased quality is equivalent to the level of the poorer performing intra-subspecies parental mean., BRUMMER (1999) suggested increasing yield in alfalfa could be effected by using a semihybrid system to capture natural hybrid vigor found in crosses between populations. By identifying specific heterotic patterns [...]

Tall wheatgrass [Thinopyrum ponticum (Podp.) Liu and Wang] is a cool-season bunchgrass from southern Europe and Asia Minor that is tolerant to saline or alkaline soils. The genetic base of tall wheatgrass cultivars is narrow. The lineages of four of the six cultivars of tall wheatgrass developed and released in the USA and Canada trace to a common accession. PI 98526. The objective of this study was to determine the extent of variation in the USDA collection of tall wheatgrass for forage quality, yield, and other agronomic traits. All available accessions of tall wheatgrass (n = 50) from the USDA Western Regional Plant Introduction Station at Pullman, WA, and two check cultivars. Platte and Jose, were used in the study. Greenhouse grown seedlings were transplanted in 1989 into a replicated field evaluation nursery located about 35 km west of Omaha, NE. An evaluation plot consisted of a single row of 10 plants spaced on 1.1-m centers. The experimental design was a blocks-in-replicates design with two replications. The plots were evaluated for forage yield and quality including in vitro dry matter digestibility (IVDMD). protein content, and other traits in 1990 and 1991. Several of the PI lines had forage yields equivalent to the check cultivars. One accession. PI 98526, had higher first harvest IVDMD than the check cultivars: other accessions had IVDMD values equivalent to the check cultivars. In addition to having high yields and high IVDMD, these accessions also were equivalent to the check cultivars in other agronomic traits as indicated by high leafiness and inflorescence scores. The results indicate that superior germplasm exists in the USDA tall wheatgrass germplasm collection that can be used to develop improved cultivars of tall wheatgrass with improved forage quality as measured by IVDMD., Tall wheatgrass, [Thinopyrum ponticum (Podp.) Liu and Wang] (Asay and Jensen, 1996) or Elytrigia elongata (Host) Nevski (Alderson and Sharp, 1994), is a perennial, decaploid (2n = 70) cool-season bunchgrass [...]

Crops is a global journal of crop science that has been publishing articles for two years. It recently reached a milestone of publishing its 50th article and is now considered an established journal. Crops aims to be inclusive of all plant species grown for various purposes and is committed to open access. The journal's goal is to bring together different disciplines in crop sciences and publish the best research from around the world. Researchers in the field are encouraged to submit their work to Crops for a global audience. [Extracted from the article]

Improved forage yield and quality, which can lead to more efficient livestock production, are important goals in switchgrass (Panicum virgatum L.) breeding. Objectives of this study were to determine the effectiveness of multiple cycles of recurrent restricted phenotypic selection (RRPS) in improving forage yield in switchgrass and in improving in vitro dry matter digestibility (IVDMD), and to compare predicted and realized gains from selection. Six switchgrass populations were developed by selecting a base population for one cycle of low and three cycles of high IVDMD and two cycles for high yield. Half-sib progenies of parents selected from the base population for high and low IVDMD were used to estimate heritability for IVDMD by parent-progeny regression. Realized gains from selection were determined in a seeded sward trial that included the base and six selected populations. Estimated and realized heritabilities for IVDMD were 0.40 and 0.31, respectively. Predicted pins and (in parenthesis) realized gains from selection for I'MD in grams per kilogram per cycle were - 21 (- 15) for the Low IVDMD Cycle 1, 16 (15) for the High IVDMD Cycle 1 (|Trailblazer'), 14 (4) for the High IVDMD Cycle 2, and 19 (18) for the High IVDMD Cycle 3 populations. There was a low but positive genetic correlation between forage yield and RVDMD of 0.10. Forage yield was not improved by RRPS, probably because of lack of genetic variability for forage yield in the base population. It is concluded that RRPS is effective for improving I'MD in switchgrass, but was not effective in improving forage yield in the populations evaluated, and that predicted gains exceeded realized gains from selection for IVDMD due to limited selection for traits other than IVDMD.

Field pennycress (Thlaspi arvense L.) (PC) and winter camelina [Camelina sativa (L.) Crantz] (WC) have the potential to provide ecosystem services and economic incentives when adopted as an oilseed cover crops in corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotations. However, PC and WC establishment and yield in the northern Corn Belt and their subsequent impact on row crops are not well known. This study was conducted to determine the effects of interseeding dates (R4, R5, and R6; and R6, R7, and R8 development stages for corn and soybean, respectively) and cover crop species (PC, WC, and winter rye [Secale cereale L.]) on seed yield and oil content of interseeded oilseeds (PC and WC) and relay soybean, and 3rd‐year corn grain yield and quality. Study sites were initiated near Ames, IA; Morris and Rosemount, MN; and Prosper, ND. Late interseeding of PC and WC resulted in greater oilseed yield. Overall yields of PC (218–880 kg ha–1) and WC (15–770 kg ha–1), averaged across interseeding dates, were low when interseeded in corn and soybean. The PC and WC reduced relay‐soybean grain yield by 13–32% and 13–42%, respectively. Corn grain yield and quality following relay soybean were not affected by the residual effects of oilseed cover crops. Based on the results of our study, we do not recommend relay cropping soybean with PC and WC in the upper Midwest. Core Ideas: Late interseeding of oilseed cover crops produced greater seed yield than early interseeding. Oilseeds yield of pennycress (218–880 kg ha−1) and winter camelina (15–770 kg ha−1) were low. Soybean yield relayed into pennycress and winter camelina was reduced by 13–42%. No residual effect of oilseed cover crops on grain yield or quality of subsequent season corn. [ABSTRACT FROM AUTHOR]

The demand for natural fibers is increasing worldwide as markets respond to the need to replace nonrenewable sources. Kenaf (Hibiscus cannabinus L.) is a promising biorenewable resource for producing natural fibers. Few studies have investigated the crop when grown at latitudes above 40° and in the U.S. Midwest. The objectives of this study were to assess the influence of management practices on fiber (bast and core lignocellulose) composition, carbon (C), nitrogen (N), and total ash concentration. Cultivars 'Tainung 2' and 'Whitten' were planted in Boone County, IA in 2014 and 2015 at 247,000 or 371,000 seed ha−1, in 38‐ or 76‐cm rows, and fertilized with N at 0, 56, 112, 168, or 224 kg ha−1. Treatments were in a factorial design with four replications in 2 yr. Stem bast and core lignocellulose concentrations, total ash, and C/N ratio were determined at harvest. Variety or interactions of variety with management practices influenced most parameters. Increased N fertilization decreased bast cellulose concentration, but increased core cellulose concentration. Hemicellulose concentration in core was greater than in bast. Ash concentration decreased as N fertilization rate increased and interacted with seeding rate and variety. The implications of these observations are directly related to markets and desired kenaf end‐use products. Variety and management interactions influence kenaf fiber quality, and consequently are important considerations for kenaf producers and processors. [ABSTRACT FROM AUTHOR]

Since the 1980s, there has been a growing trend toward accountability in education. Policies such as No Child Left Behind1 and the Race to the Top2 have tied federal education dollars to quantifiable school performance, resulting in the passage of state-mandated assessments of student learning and more stringent evaluation of teachers.3 Responding to these measures, some educators have looked to large-ensemble festivals to provide evidence of student growth in music performance classes, and music associations in several states have renamed their large-ensemble festivals "music performance assessments"4 For example, Kentucky relabeled its festivals in 2013 "to better reflect [their] assessment value" while making no structural changes to the event.5 While festivals are a type of assessment, a full investigation of their nature and development is needed before their use in this context should be deemed appropriate. To date, there have been no such investigations. Because the national band and orchestra contests terminated in the 1930s, determining their evolution afterward must come by examining state festivals.6 The purpose of this historical study was to determine the character and nature of large-ensemble festivals in Michigan, another state that recently considered relabeling festivals as assessments. Primary source material consisted of reports, minutes of meetings, and other publications and documents held in the archives of the Michigan School Band and Orchestra Association, as well as interviews with past Association officers. Data were collected as researcher notes and recorded in a database using standard spreadsheet software to allow organizing, coding of themes, and sorting; this database became a timeline of the festival's development from 1938 to the present. Research questions addressed 1) the historical context regarding large-ensemble festival development; 2) the factors that shaped festival systems after their inception; 3) whether current festivals are, by nature, contests, performance events, academic assessments, or a combination of these; 4) whether or not festivals should be used in conjunction with teacher evaluation. After reviewing the contest/festival historical literature and discussing the influence competition has had on music education, I will closely examine how large-ensemble festivals evolved in Michigan. I will also discuss the implications the current study has for festival practices and music education policy. [ABSTRACT FROM AUTHOR]

Development of perennial biomass cropping systems is focused on maximizing biomass yield with minimum inputs, particularly nitrogen (N) fertilizer. Historical breeding efforts have focused on increasing biomass yield but have ignored N-use efficiency. The purpose of this study was to quantify the increased N demand associated with realized gains in biomass yield from big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) breeding programs. Nitrogen demand was highly variable across locations and years, ranging from − 1.7 to + 6.8 kg N Mg−1 DM, with an average of 2.2 kg N Mg−1 DM. Increases in N demand were closely associated with realized gains in biomass yield and were observed for all types of switchgrass (upland, lowland, and hybrid) as well as for big bluestem. Attenuation of these responses will require alternative breeding schemes that are focused on evaluation of switchgrass genotypes and progeny under low-N conditions and include a high-throughput tissue N analysis as a component of future selection criteria, designed to develop new cultivars with high biomass yield and low tissue N. [ABSTRACT FROM AUTHOR]

Increasing the number of nodes for subsequent pod development by soybean [Glycine max (L.) Merr.] may be an approach to improve yield. Land rolling is a common practice in soybean production to push rocks and corn (Zea mays L.) root balls back to the soil surface to protect combine harvesters. Limited research has been done to determine if land rolling can change plant architecture by breaking the apical dominance of soybean to induce lateral branching and provide greater node and pod numbers. The objective of this experiment was to determine if land rolling soybeans could break apical dominance to induce lateral branching, increase reproductive node number, and improve yield. Field experiments were conducted in 2017 and 2018 in a randomized complete block design with five replications. Treatments consisted of a control that was not rolled, rolling beforeemergence, and rolling at the V2, V3, and V4 stages of development. Data included counts of main stems and branches, nodes on main stems, branches that did or did not have pods, pod numbers on main stems and branches, stand density, and grain yield. Land rolling decreasedmain stemnumbers, and reproductive nodes and pods onmain stems. Land rolling soybean after emergence consistently decreased stand density in 2018 but only decreased stand density on one of three post-emergence timings in 2017. However, land rolling did not influence branch numbers or branch nodes and pods. Land rolling influenced soybean plant architecture but did not influence yield when done before or after emergence. [ABSTRACT FROM AUTHOR]