bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expert System for Planning the Establishment of Turfs
Authors: Liu H. , Fermanian T.W. , Carmer S.G. 
Published: July 2010

AbstractEstablishing or renovating sites are routine events in the management of turfgrasses. Advice from turf experts on the design of the new turf is not always readily available, due to limitations on information about design and utility parameters. Knowledge‐based advisory systems, commonly called expert systems, have shown great potential for planning tasks. TURFPLAN, an expert planning system, was constructed principally for turf managers, Extension staff, educators, contractors, etc. The major design tasks of TURFPLAN are the selection of turfgrass species and their cultivars, establishment procedures, and maintenance procedures during the post‐planting period. Expert System Environment (ESE) was selected as the development platform for TURFPLAN. A portion of the rules covering the selection of turfgrass cultivars was developed from examples using AURORA, an inductive learning system. An evaluation of TURFPLAN's performance was conducted by comparing a set of generated designs to comparable designs developed by turf experts. The TURFPLAN design for a medium maintenance turf (home lawn) was ranked significantly superior to human produced designs. TURFPLAN establishment designs for low maintenance turfs (i.e., highway rights of way) and high maintenance turfs (i.e., golf course greens) were ranked significantly poorer than designs developed by human experts. The TURFPLAN knowledge base currently does not have an adequate quantity of knowledge specifically related to the establishment of low or very high maintenance level turfs. This evaluation indicated that a knowledge‐based planning system may provide turf establishment designs of high quality for home lawns in Illinois. This method of evaluation also establishes a systematic procedure for evaluating knowledge‐based systems.
Interpretive Analysis for Forage Yield Trial Data
Authors: Pedersen J. F. , Moore K. J. , van Santen Edzard 
Published: July 2010

AbstractForage cultivar evaluation is often done in small plots with multiple harvests throughout the growing season. Data is often summarized by presenting a yearly total yield for each cultivar in addition to the mean for each harvest date. Data summarization often becomes burdensome and difficult to interpret. Regressing yield against a growth index associated with harvest dates can be utilized to describe forage perfomrmance in a concise and easily interpreted format. Subsets of data from tall fescue (Festuca arundinacea Schreb.) yield trials conducted in Alabama and Kentucky were used to demonstrate the technique. The analysis involves regressing yield of a cultivar against an index calculated as the mean of all entries at a harvest date minus the grand mean. The resulting regression coefficient (b) describes cultivar yield response over several harvest and is indicative of performance under variable growth conditions.
Productivity and Quality of Bermudagrass in a Cool Temperate Environment
Authors: Belesky D. P. , Perry H. D. , Windham W. R. , Mathias E. L. , Fedders J. M. 
Published: July 2010

AbstractIn temperate environments a warm‐season species is needed to provide forage during summer when the growth rate of cool‐season forages is low. Management data for warm‐season pasture is limited for the Appalachian region. A bermudagrass [Cynodon dactylon (L.) Pers.] selection RS1, has been identified which is capable of growth and persistence in areas where other cultivars of the species winterkill. A field study was conducted to determine RS1 bermudagrass productivity and quality as affected by a split application of 60, 120, 240, or 360 kg N ha−1 and a 2‐, 4‐, or 6‐wk delay of initial harvest on a fine‐loamy, mixed, mesic, Typic Hapludult (Gilpin) soil. Treatments were replicated four times in the field, and the study was conducted for 2 yr. Delaying initial harvest significantly increased yield in both years to more than 8 Mg ha−1 when 360 kg N ha−1 yr−1 was applied. Herbage yields typically ranged between 3 and 6 Mg ha−1 and would contribute substantially to forage requirements in mid‐summer in the region. Increased N resulted in higher herbage yield regardless of harvest delay regime. Herbage yields were about 25% less in 1989 than in 1988 and could be due in part to cool and wet conditions in 1989, compared to a hot, dry 1988 growing season. Bermudagrass in vitro dry matter digestibility and crude protein declined with delayed initial harvest (maturity), increased following the mid‐season N application, and continued to decline into late summer. Season average quality was not affected by initial harvest delay. Bermudagrass (RS1) will persist and respond to N fertilizer and defoliation management in cool, temperate environments and promises to be a useful component in forage‐based animal production systems in the region
Optimum Seeding Date for Winter Wheat in Southwestern Saskatchewan
Authors: McLeod J.G. , Campbell C.A. , Dyck F.B. , Vera C.L. 
Published: July 2010

AbstractWinter wheat (Triticum aestivum L.) in southern Alberta on the Canadian Prairies has traditionally been grown on bare fallow. Recently, the improved winterhardy cultivar Norstar and improved management recommendations, such as seeding directly into stubble or into chemical fallow, have encouraged producers to adapt this crop to the colder climate of southern Saskatchewan. The objective of the experiments reported herein was to determine if the optimum time for seeding winter wheat on stubble and chemical fallow differed from that recommended for seeding on conventional fallow in southern Alberta. A 4‐yr study of stubble‐seeded wheat and 3‐yr study of wheat seeded on chemical fallow were carried out on a medium‐textured soil at Swift Current and on a coarse‐textured soil at Cantuar (only the stubble treatment). The results for stubble‐seeded wheat confirmed that both plant population and yields decreased sharply by 40 to 60% and 30 to 40%, respectively, as seeding was delayed after the first week of September until very late October. The decrease in plant population was less pronounced on the sandy loam soil (40%) than on the silt loam soil (56%). On chemical fallow, there was a gradual decrease in plant population but grain yield did not decrease until seeding was delayed to mid‐October. Test weight was reduced (about 8%) by delayed seeding, and plants took 10 to 13 d dlonger to mature, which facilitated disease (e.g., rust) infestation. Grain protein concentration was not affected by time of seeding. For optimum results in southwestern Saskatchewan, winter wheat can be seeded into chemical fallow until early October but should be seeded in stubble by mid‐September.
Creeping Bentgrass Rooting as Influenced by Dithiopyr
Authors: Dernoeden P. H. , Christians N. E. , Krouse J. M. , Roe R. G. 
Published: July 2010

AbstractDithiopyr [3,5‐pyridinedicarbothioic acid, 2‐(difluoromethyl)‐4(2‐methylpropyl)‐6‐trifluoromethyl)S,S‐dimethyl ester] is a new herbicide, but its foliar safety and potential rooting effects need to be documented before its use on creeping bentgrass (Agrostis palustris Huds.) can be recommended. Field studies were conducted at five separate sites in Iowa and in Maryland, where creeping bentgrass was grown on modified sandy soils and maintained at putting green height. Three dithiopyr formulations (1.0 emulsifiable concentrate, 0.10 granular, 0.25 granular) at rates ranging from 0.28 to 0.84 kg ha−1 were compared with label rates of either bensulide [O,O‐bis (1‐methylethyl) S‐(2‐[(phenylsulfonyl)amino] ethyl] phosphorodithioate] or bensulide + oxadiazon [3‐[2‐4‐dichloro‐5‐(1‐methylethoxy)phenyl]‐5‐(1,1‐dimethylethyl)‐1,3,4‐oxadiazol‐2‐(3H)‐one] or DCPA [dimethyl 2,3,5,6‐tetrachloro‐1, 4‐benzenedicarboxylate] for potential rooting and foliar discoloration effects. Root masses were obtained from washed soil plugs, which were combusted to determine root weight. In Iowa all herbicides reduced total root weight on one of four sampling dates in 2 yr. No rooting differences were observed among herbicide rates or formulations at soil depths partitioned at 0 to 5, 5 to 10, 10 to 15, or 15 to 20 cm. Reduced root weight was observed with all herbicides on at least one of nine sampling dates in Maryland. Root weight reduction in Maryland studies was observed primarily within 29 d of treatment (DAT) in 1990, but not within 57 DAT in 1990 or on six sampling dates in 1991. No foliar discoloration was elicited by dithiopyr applied in either April or May. Discoloration and cover reduction occurred where dithiopyr 1.0 EC (0.84 kg ha−1) and bensulide + oxadiazon (6.7 + 1.7 kg ha−1) were applied in mid‐June in Maryland. Overall, data indicate that dithiopyr (0.28‐0.84 kg ha−1) had an acceptable safety margin for creeping bentgrass foliage and rooting on putting greens when applied preemergence in spring.
Leaf Expansion in Field‐Grown Sunflower in Response to Soil and Leaf Water Status
Authors: Sadras V. O. , Villalobos F. J. , Fereres E. 
Published: July 2010

AbstractLeaf responses to soil water deficits in controlled environments may be mediated by nonhydraulic root signals (RS). The aim of this study was to evaluate in the field the effects of RS and leaf water potential (Ψ1) on leaf expansion rate (LER) of sunflower (Helianthus annuus L.). Two experiments were performed on a deep sandy‐loam soil (Typic Xerofluvent) in a Mediterranean environment under spring (Exp. 1) and summer conditions (Exp. 2). WET and DRY treatments were established at the 16th‐leaf stage in both experiments. WET plots were irrigated daily with an amount of water equal to the reference evapotranspiration of the previous day. DRY plots received no water during the treatment period which was maintained until LER declined to about 30% of the WET controls. A split‐root (SR) treatment with the root zone divided in dry and wet sections was included in Exp. 2. Soil water content (θa), LER and Ψ1 were measured. Responses of LER to soil drying were better described by Ψ1 than by plant available water (PAW); i.e., the response of LER to PAW depended on evaporative demand, whereas a single regression of Ψ1 on LER fitted all the data (P < 0.001). Leaf expansion rate and Ψ1 of DRY plants began to decline with respect to that of WET plants at similar PAW thresholds. The soil water content in the dry soil zone of the SR plots was similar to that in the DRY plots during the first week of treatment whereas θa in the wet zone allowed SR plants to maintain a water status similar to that of WET controls. Split‐rooted plants did not behave as DRY controls, as expected in the case of a significant root signal effect, but maintained LER similar to the WET plants. It is concluded that, under the conditions of the present experiments, hydraulic effects were probably of more importance than nonhydraulic root signals in the regulation of sunflower leaf expansion.
Seed Quality and Yield of Early‐Planted, Short‐Season Soybean Genotypes
Authors: Mayhew W. L. , Caviness C. E. 
Published: July 2010

AbstractA new soybean [Glycine max (L.) Merr.] production system, in which early‐maturing indeterminate cultivars are planted in early April, has been used by some growers in Arkansas and other Southern states. The intent is to escape late‐season moisture deficits. This research was conducted to measure seed yield and seed quality (as determined by seed germination and viability) of Maturity Group (MG) III and IV genotypes planted in early April of 1989 and 1990 under nonirrigated conditions at three locations in Arkansas (approximately 34° to 36° N lat). Yields across the six environments averaged 1816 and 1992 kg ha−1 for four MG III and four MG IV cultivars, respectively. ‘Williams 82’ produced the highest average yield (2072 kg ha−1) in MG III and ‘Competitor’ produced the highest (2110 kg ha−1) in MG IV. Seed germination was 32 and 39% for MG III and IV, respectively (average of six environments). Poor seed germination was associated with infection with Phomopsis longicolla T.W. Hobbs, one of the causal organisms of phomopsis seed decay (PSD). PI 417479 had significantly less PSD‐infected seed than the other genotypes in three environments and averaged only 4% infection when all environments were included. Yield of early‐planted, nonirrigated MG III and IV indeterminate cultivars was = 16% greater than for nonirrigated conventional cultivars, but the seed produced had low germination and viability. Highyielding, early‐maturing cultivars with resistance to PSD need to be developed if this new production system is to be a viable management option for growers in the soybean production region of the U.S. South.
Tillage and Weed Management Affects Winter Wheat Yield in an Integrated Pest Management System
Authors: Young F. L. , Ogg A. G. , Papendick R. I. , Thill D. C. , Alldredge J. R. 
Published: July 2010

AbstractAdoption of conservation practices by U.S. Pacific Northwest growers to meet farm bill legislation for erosion control is limited by the inability to control weeds and other pests in cereal and pulse crops. A 6‐yr, 16‐ha integrated pest management field study was conducted in the subhumid wheat area of the Pacific Northwest from 1985 through 1991 to develop a crop production system that controls weeds effectively and reduces soil erosion. Farm‐size machinery were used to till, plant, and harvest crops grown in either a continuous wheat (Triticum aestivum L.) sequence or a 3‐yr rotation of winter wheat‐spring barley (Hordeum vulgare L.)‒spring pea (Pisum sativum L.) in conservation and conventional tillage systems. Minimum, moderate, and maximum weed management levels were superimposed over each cropping by tillage system. Position of winter wheat within a cropping system influenced yield so that wheat produced more grain following spring pea > spring wheat >> winter wheat. Insects and root diseases were not yield‐limiting factors in either conventionally tilled monoculture wheat or no‐till wheat in the 3‐yr cropping system. Yield of winter wheat in the conventionally tilled, continuous wheat system was similar for all three weed management levels. Yield of winter wheat in conservation tillage systems increased at both the moderate and maximum level of weed management compared with the minimum level. No‐till winter wheat planted after either pea or spring wheat at the moderate and maximum weed management levels yielded a minimum of 605 kg ha−1 more than conventionally tilled wheat at the same management levels.
Water Use by Annual Green Manure Legumes in Dryland Cropping Systems
Authors: Biederbeck V. O. , Bouman O. T. 
Published: July 2010

AbstractData on plant water use and soil water depletion by green manure legumes are needed to develop sustainable cropping systems in a semiarid environment. The objectives of this study were to determine: (i) seasonal water use by legumes, (ii) their water use efficiency (WUE), and (iii) residual soil water contents after legume growth compared with summerfallow and continuous spring wheat (Triticum aestivum L.). Black lentil (Lens culinaris Medikus), Tangier flatpea (Lathyrus tingitanus L.), chickling vetch (Lathyrus sativus L.), and feed pea (Pisum sativum L.), were seeded into wheat stubble with snow trap strips on an Orthic Brown Chernozem soil (Aridic Haploborolls) at Swift Current, SK, from 1984 to 1990. Legume water use exceeded that of fallow at 4 to 6 wk after seeding. When legumes were tilled into the soil at full bloom, differences in water content between cropped treatments and fallow were largest and most consistent in the top 0.6 m, suggesting that the legumes extracted water primarily from this depth. In an extreme drought year, substantial water depletion occurred below 0.6 m. Water use efficiency of legumes was 11 to 29 kg ha−1 mm−1, similar to that of spring wheat. Feed pea and chickling vetch used water more efficiently than the other legumes or N‐fertilized wheat. Significant differences in WUE across years were related to differences in DM production. Soil water contents above the 0.6‐m depth in late fall following green manuring were 62 to 82% that of fallow and increased over winter to 79 to 103% of fallow. Subsoil water was, on average, recharged after wheat to only 68% but following green manure to 81% of fallow. Partial fallow replacement with legumes would reduce the risk of erosion and nutrient leaching and minimize the hazard of salinization and eutrophication of downstream ecosystems.
Influence of Residue Removal Method and Herbicides on Perennial Ryegrass Seed Production: I. Weed Control
Authors: Mueller‐Warrant George W. , Young William C. , Mellbye Mark E. 
Published: July 2010

AbstractGrass seed production in the Pacific Northwest is in transition from reliance on open‐field burning to systems integrating mechanical removal of postharvest crop residues with chemical weed control. Field tests of the ability of these systems to meet current seed certification standards while maintaining normal seed yields were initiated in 1989. Fourteen herbicide treatment sequences plus an untreated check were evaluated under five residue removal systems at two sites during two consecutive growing seasons. Residue removal methods were three nonburn systems varying in thoroughness of residue removal and two methods of burning. Among the nonburn systems, adequate control of volunteer perennial ryegrass (Lolium perenne L.), the most abundant weed in all tests, was most readily achieved in plots where residue was most thoroughly removed. Herbicide treatments providing the best weed control in both years at both sites included preemergence (PRE) metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐1‐methylethyl) acetamide] followed by postemergen (POST) oxyfluorfen [2‐chloro‐1‐(3‐ethoxy‐4‐nitrophenoxy)‐4‐(trifluoromethlyl)benzene)] plus diuron [N'−3, dichlorophenyl)‐N,N‐dimethylurea], PRE metalochlor followed by POST diuron, and PRE pendimethalin [N‐(1‐ethylpropyl)‐3,4‐dimethyl‐2,6‐dinitrobenzenamine] followed by POST oxyfluorfen plus metribuzin] [4‐amino‐6‐(1,1‐dimethylethyl)‐3‐(methylthio)‐1,2,4‐triazin‐5(4H)‐one]. PRE pendimethalin followed by POST oxyfluorfen plus diuron provided adequate weed control in most residue removal systems, but was marginal in the least thorough residue removal system. With properly chosen herbicide treatments, seed certification standards for perennial ryegrass can be met without field burning.
Growth and Development of Soybean Isolines that Differ for Maturity
Authors: Wilcox John A. , Wiebold William J. , Kephart Kenneth D. , Niblack Terry L. 
Published: July 2010

AbstractIsolines for maturity within a common background may be useful in research that attempts to determine the effect of maturity group adaptation on soybean [Glycine max (L.) Merr.] growth or yield. Although the effects of maturity genes on soybean phenology have been studied extensively, little is known about their effects on other soybean characteristics. Field experiments were conducted near Columbia, MO, in 1991 and 1992 to determine the effects of three major maturity genes on growth and development of soybean. Four near‐isogenic strains (isolines) were replicated four times in a completely randomized design: L71‐920 (e1e2e3), Clark (e1E2E3), L74‐441 (E1E2e3), and L67‐1474 (E1E2E3). Vegetative and reproductive characteristics were recorded for five plants within each plot. Late‐maturing isolines were taller and had more leaves than early‐maturing isolines, but stem growth and leaf initiation rates were similar. Late‐maturing isolines produced more flowers and pods because they had more nodes than early‐maturing isolines. Late‐maturing isolines produced more than 25% of total yield on branches, whereas early‐maturing isolines produced approximately 10% of total yield on branches. Because the isolines used in this study had consistent differences for plant phenology, they can be useful components of experiments that include maturity as a factor. However, changes in phenology also changed plant morphology.
Production of Prenuclear Minitubers of Potato with Peat‐Based Arbuscular Mycorrhizal Fungal Inoculum
Authors: Niemira Brendan A. , Safir Gene R. , Hammerschmidt Raymond , Bird George W. 
Published: July 2010

AbstractPrenuclear minitubers of potato (Solanum tuberosum L.) are the source material used to produce field‐grown seed potatoes. Seed potatoes are in turn planted by commercial growers to produce potatoes for fresh packing and processing. Arbuscular mycorrhizae (AM) have been demonslrated to increase yield in low‐input systems. This study was conducted to determine whether and how a commercial AM inoculum influences prenuclear minituber production under high‐input commercial conditions. A peat‐based medium containing the mycorrhizal fungus Glomus intraradix was tested in a commercial minituber greenhouse production facility. This medium increased yields of the most valuable sizes of prenuclear minitubers by 84%, and increased total prenuclear minituber yield by 49% when compared with conventional peat‐vermiculite media under commercial growing conditions. Potato plants grown in this mycorrhizal medium had more uniform stolon development, as well as stolons 39% longer than plants grown in the conventional medium. These yield increases and morphological changes occur in the presence of very low levels of mycorrhizal colonization, and there was no evidence of the enhanced plant P nutrition generally associated with mycorrhizal symbiosis. These effects may indicate the presence of a hormonally mediated plant response to the mycorrhizae that results in more uniform stolon growth and an increase in tuber initiation.
A Portable Electronic Device for Evaluating Root Lodging Resistance in Maize
Authors: Fouéré Alain , Pellerin Sylvain , Duparque Annie 
Published: July 2010

AbstractBecause climatic conditions conducive to natural lodging of maize (Zea mays L.) are sporadic and unreliable, a need exists for methods of evaluating the resistance of genotypes to root lodging. A portable electronic device was built for horizontal pushing resistance measurements on individual plants. The apparatus simultaneously records the angle of inclination and the resistance torque of the plant during an artificial pushing test. The device consists of a support, a force sensor, an angle sensor, and a control head. Data logging is possible by using a microprocessor‐based system. Data may be transferred to a computer using an RS232 serial transfer protocol. The time required for the test in field conditions is approximately 1 min per plant. Preliminary results obtained on 14 maize genotypes grown in three field environments showed that genotypes susceptible to root lodging were characterized by low average values of their maximum resistance torque.