bluuebunny/crossref_metadata_2025_split huggingface dataset:
Germination and Emergence Response of Common and Tepary Beans to Controlled Temperature1
Authors: Scully B. , Waines J. G. 
Published: July 2010

AbstractSoil temperature strongly influences the germination and emergence of common beans (Phaseolus vulgaris L.) and tepary beans (Phaseolus acutifolius A. Gray). The purpose of this investigation was to identify accessions of both species that could potentially germinate and emerge under cool soil conditions, and to determine an optimum germination temperature for tepary beans. Germination of 129 common and 18 tepary bean accessions was initially evaluated at 10°C. The 10 earliest common and the five earliest tepary beans to germinate were entered into an emergence test at three temperatures (12, 14, and 16°C). The common beans emerged 1 day earlier than the teparies at 12 and 14°C, while the teparies emerged 1 day earlier at 16°C. The most cold‐tolerant common bean at emergence was PI 165‐426, while accessions G40034 and PI 319‐443 displayed the highest cold tolerance among the tepary beans. Subsequently, tepary beans were compared to common beans for germination response over six temperatures from 10 to 35°C. In general, tepary and common beans took approximately the same time to germinate except at 35°C where teparies germinated faster. A scarification experiment was undertaken with the same six temperatures as above to determine any effects of the seedcoat on tepary bean germination. Scarification generally resulted in an earlier germination response, but the effect was small. Both germination experiments indicate that the optimum temperature range for teparies is 25 to 35°C, whereas it is lower, 20 to 30°C, for common beans.
Induction of Tobacco Seed Germination Synchrony through Dark Preincubation1
Authors: Mohapatra S. C. , Arcila J. , Johnson W. H. , Nelson L. A. 
Published: July 2010

AbstractNicotiana tabacum cv. Speight G‐28, a popular cultivar of bright leaf tobacco, has a high percentage of seed germination but it takes a long time (nearly a week under laboratory conditions and several weeks under field conditions) to give maximum germination. This study was undertaken to develop a laboratory seed treatment to improve germination synchrony. Twenty‐three seed treatments, including the control, were developed through the use of dark‐preincubation (DPI), polyethylene glycol (PEG) or chilling alone, or in various combinations thereof. An index of synchrony (IS) was calculated from the formula,

urn:x-wiley:00021962:agj2agronj198700021962007900030012x:equation:agj2agronj198700021962007900030012x-math-0001 The theoretical highest value of the IS for a given seed lot would be 1.0. In absence of an absolute synchrony, the practical objective of a given seed treatment would be to raise the IS as close to 1.0 as possible. All the 23 seed treatments tested were ranked on the basis of this consideration. Treatments giving 0.8 or greater IS are, indecreasing order: DPI at 23°C for 1 week followed by DPI for 1 week under chilling (0.95); DPI under chilling for 1 week followed by DPI at 23°C for 1 week (0.93); DPI at 23°C for 1 week followed by chilling under light for 1 week (0.90); and DPI at 23°C for 1 week (0.81). As compared to these treatments, the IS of the control was 0.52. Possible physiological mechanisms involved in DPI‐induced germination synchrony and the potential for practical application of this treatment are discussed.
Potassium, Boron, Nitrogen, and Lime Effects on Corn Yield and Earleaf Nutrient Concentrations1
Authors: Woodruff J. R. , Moore F. W. , Musen H. L. 
Published: July 2010

AbstractIntensified production practices have included irrigation and higher‐than‐traditional rates of N and K to reach high yield goals for corn (Zea mays L.). Previous studies have shown that B is low in southeastern Coastal Plain soils and that additions of high rates of N, K, and lime to soils low in B may decrease B availability. This 3‐yr factorial experiment was conducted on a Dothan loamy sand (Plinthic Paleudults) to examine the effects and interactions of B, K, N, and lime on corn yield and earleaf nutrient concentrations with the objective of better defining B needs of intensive corn production. Two levels of B (0 and 2.24 kg ha−1), K (131 and 317 kg ha−1), N (202 and 426 kg ha−1), and lime (0 and 1120 kg ha−1) were employed. Corn yields showed a positive response to N in 1982, a negative response to lime in 1983, and no response to individual factors in 1984. There was a trend in 1982 and 1984 toward less yield (average 18.2% less) where high K was added with no B, compared to where low K was added with no B. There was a significant B ✕ K interaction effect (P≤0.05) on yield in 1984, and the same effect (P≤0.01) appeared for the 3‐yr combined analysis of variance. Earleaf B was influenced by N ✕ B interaction in 1982 and lime ✕ K interaction in 1984. The results showed that B fertilization was necessary to prevent yield reduction where high K fertilization was used.
Purpling in Maize Hybrids as Influenced by Temperature and Soil Phosphorus1
Authors: Cobbina J. , Miller M. H. 
Published: July 2010

AbstractPurpling in maize (Zea mays L.), which has been prevalent in Ontario in recent years, has been attributed to combinations of P deficiency, low temperature, and genotype. The intensity of purpling in maize hybrid seedlings grown in growth rooms in an Aqnic Hapludalf soil at three P levels (4,22,100 mg L−1 NaHCO3‐extractable P) and two air temperatures (15/10 and 25/20°C, light/dark) was studied to determine the extent to which differential purpling at low temperature could be attributed to variable shoot P concentration. All hybrids tested (Pioneer 3720, 3732, 3780A, 3949, PAG SX111, Pride 1169) showed some purpling at very low soil P and 15/10°C temperatures. At 25/20°C and very low soil P, Pioneer 3732 and Pride 1169 were severely purpled, Pioneer 3780A and PAG SX111 were intermediate, and Pioneer 3720 and 3949 had the least purpling. Although intensity of purpling decreased with increasing P concentration in shoots, at 15/10°C some hybrids showed purpling even with 5 g P kg−1 DM in shoot. Hybrids differed markedly in intensity of purpling at similar P concentration. Anthocyanin content decreased with increasing shoot P concentration, but there were marked differences among hybrids in anthocyanin content at a given shoot P concentration. There were also marked differences in degree of purpling among hybrids with similar anthocyanin contents. The effects of genotype and temperature on degree of purpling may be due to: (i) reduced shoot P concentration; (ii) higher anthocyanin content regardless of shoot P concentration; or (iii) greater purpling at similar anthocyanin contents. The appearance of purple color in maize seedlings is not necessarily due to inadequate P concentration in the plant.
Root Growth Rate of Soybean as Affected by Drought Stress1
Authors: Hoogenboom Gerrit , Huck M. G. , Peterson Curt M. 
Published: July 2010

AbstractRoots play an important role in plant survival during periods of drought. A 3‐yr study was performed to investigate the effect of drought stress on daily root growth rates of soybean [Glycine max (L.) Merr. ‘Braxton’] plants grown in a Marvyn loamy sand (fineloamy, siliceous, thermic Plinthic Paleudult) at the Auburn rhizotron. During each growing season, plants received either rainfall (NI) or rainfall and supplemental irrigation (IR) controlled by tensiometers installed at a 0.4‐m depth. Root growth was estimated by measuring the length of new roots visible at the glass viewing surface at regular intervals throughout the growing season. Bins were excavated at the end of the 1983 growing season to estimate total root biomass. Roots of both IR and NI plants grew in the upper soil regions (above 0.4 m) during early vegetative growth (V1–V4) and then gradually penetrated into deeper layers, at a rate of 0.5 to 1 m/(m2 day). A large increase in root growth [up to 6 m/(m2 day)] was observed when drought stress occurred during later stages of vegetative growth or early reproductive development (R1–R2). Root growth was less affected by drought [<1 m/(m2 day)] after plants had reached the pod development stage (R4) and finally ceased during seed fill (R5). The IR plants mainly produced roots in soil layers above 0.6 m, while roots of NI plants penetrated deeper soil layers (>0.6 m), especially during drought periods. After rainfall, root growth rates decreased in both treatments. At the end of the season, NI plants had significantly larger root systems (total root length) than IR plants, but total root mass (tap roots and secondary roots) between the two treatments was similar
Midseason Soil Water Recharge for Corn in the Northwestern Corn Belt1
Authors: Johnson Bradley S. , Blake George R. , Nelson Wallace W. 
Published: July 2010

AbstractIncomplete soil water recharge between fall harvest and spring planting, and insufficient growing‐season precipitation limit plant growth in southwestern Minnesota. Our objectives in this study were to test the hypotheses that (i) corn (Zea mays L.) production on a fine‐textured soil of high water‐holding capacity may be increased with irrigation, and (ii) that a single application of water at midseason to partially recharge the soil water reservoir would be as beneficial to the crop as more frequent, smaller additions. Treatments consisting of irrigation timing and amounts were established in field studies conducted from 1979 to 1983 on Nicollet clay loam (Aquic Hapludoll). Soil water depletion to 0.9 m was evident during only 2 yr (1980 and 1981). A shallow water table was present in 1979 and 1980 but was not detected within 2.0 m of the soil surface from 1981 to 1983. Despite wet soil conditions and above‐normal precipitation, positive and significant grain yield responses to the addition of supplemental water were observed each year except 1982. Grain yields with a single application of 76 mm at midseason exceeded those with natural precipitation by 1.57, 2.73, and 0.72 Mg ha−1 in 1979, 1980, and 1983, respectively. No difference in grain production was noted between single midseason applications of 76 mm of water and optimum irrigation (application of 38 mm at 50% depletion of plant‐available water to a soil depth of 0.9 m). The economic feasibility of irrigation on Nicollet clay loam appears to be questionable based on yield responses to supplemental water from 1979 to 1983.
No‐Tillage Intercropped Corn Production in Tall Fescue Sod as Affected by Sod‐Control and Nitrogen Fertilization1
Authors: Wilkinson S. R. , Devine O. J. , Belesky D. P. , Dobson J. W. , Dawson R. N. 
Published: July 2010

AbstractConservation tillage methods are needed for grain production on the sloping, erodible soils of the southern Appalachian mountains. The purpose of this study was to determine rainfed no‐till corn (Zea mays L.) production in viable tall fescue (Festuca arundinacea Schreb.) sods relative to conventional tillage and complete kill no‐tillage systems. Main plot treatments were: (i) conventional tillage of fescue sod in the first year followed by no‐till planted rye in the second and third years (CT); (ii) no‐till planting in completely killed tall fescue, then in killed no‐till planted rye (NT100); (iii) no‐till planting in a 0.41‐m wide killed strip of tall fescue (NT40); and (iv) no‐till planting in a 0.20‐m wide killed strip of tall fescue (NT20). Subplot treatments consisted of 145 or 290 kg N ha−1yr−1. Adequacy of mineral nutrition for corn was evaluated by plant analysis. The experiment was conducted on a Tate loam soil (fine‐loamy, mixed, mesic Typic Hapludult) with a 5 to 15% slope. No‐till corn production (NT100) was highly successful at both N levels and yielded comparable to conventional tillage. Winter‐spring forage production was comparable whether the forage was no‐till planted rye or the remaining viable tall fescue. Competitive effects of a corn crop at 290 kg N ha−1 resulted in less summer forage for fall utilization. NT40 resulted in slightly reduced corn and forage production and soil erosion control at 290 kg N ha−1yr−1. Competition for water, N, and K limited the effectiveness of the NT20 treatment for no‐till corn production under southern Appalachian conditions.
Effects of Vegetation on Spectral Irradiance at the Soil Surface1
Authors: Heilman J. L. , Kress M. R. 
Published: July 2010

AbstractSpectral discrimination of vegetation is affected by changes in irradiance at the soil surface produced by the overlying canopy. This study was conducted to quantify effects of vegetation on spectral and spatial variations of irradiance at the soil surface. Direct and diffuse spectral irradiance were measured beneath cotton (Gossypium hirsutum L.) with a spectroradiometer for three soils differing in reflectance. At intermediate and high canopy cover, the cotton altered the spectral composition of diffuse irradiance at the soil surface in a manner that reflected the optical properties of the canopy. At shaded locations, irradiance at visible wavelengths was low due to the high absorptance of the canopy, while the near infrared irradiance was high (nearly 40% of that measured above the canopy) because of the high degree of transmission and scattering by the canopy. At sunlit locations between rows, the total irradiance (direct beam and diffuse) was lower in visible wavelengths and higher in the near infrared than that incident at the top of the canopy. Midway between rows, visible diffuse irradiance was higher and the near infrared diffuse irradiance was lower than beneath the plants. At less than 40% cover, insufficient vegetation was present to significantly affect soil irradiance. The results demonstrate that at intermediate and high canopy cover, irradiance at the soil surface contains spectral contributions from the overlying canopy. The canopy produces significant spectral and spatial variations in diffuse irradiance that should be considered in the analysis of spectral measurements.
Genotypic Variability in Response of Oat to Delayed Sowing1
Authors: Baltenberger D. C. Colville , Frey K. J. 
Published: July 2010

AbstractA classification of oat (Avena sativa L.) genotypes for reaction to delayed sowing could be used for developing cultivars that either escape the effects of or tolerate high temperatures. The effects of delayed sowing on duration of growth of nine genotypes of oat were studied in field experiments grown on a Coland loam (Cumulic Haplaquoll) soil at the Hinds Experiment Farm near Ames, IA. Sowing dates were 18 March, 2 April, 17 April, and 30 April in 1981; and 14 April, 28 April and 11 May in 1982. Number of growing degree days (GDD) and number of days to reach emergence, tiller initiation, fourth‐, fifth‐, and flag‐leaf stages, heading, and 80% panicle ripe were recorded. Plant height, biological and grain yields, and test weight were measured, and straw yield was calculated. Days and GDD required to reach each developmental stage varied significantly among genotypes. Genotypic differences occurred for plant height, biological and grain yields, harvest index, and test weight, but the differences were not associated with maturity differences. Significant variation occurred across sowing dates for plant height, grain yield, and test weight for most genotypes. Number of GDD required to reach any developmental stage across sowing dates generally was less variable than was number of days for all genotypes, indicating that GDD is a better predictor of oat cultivar development than is number of days. Thus, GDD for oat would be used much as corn heat units (CHU) are used in maize (Zea mays L.).
Aerial Parts of Hard Red Spring Wheat. II. Nitrogen and Phosphorus Concentration and Content by Plant Development Stage1
Authors: Bauer Armand , Frank A. B. , Black A. L. 
Published: July 2010

AbstractInformation is lacking on N and P concentration and content in the aerial components of hard red spring wheat (Triticum aestivum L.) at definitive development stages over its life cycle. Such information would enhance nutrient management strategies and provide algorithms for crop development/yield modelers. The concentration and content of N and P were measured in aerial components of three cultivars field‐grown 2 yr on a Williams loam (fine‐loamy, mixed Typic ArgiboroIIs) under three water and three fertilizer N levels, sampled weekly from about the three‐leaf to kernel‐hard stage.From a maximum of about 70 g kg−1, leaf N decreased linearly about 2.93 g kg−1 with each development stage, while stem N decreased curvilinearly, most rapidly between the three‐leaf and flag leaf extension stage, to a minimum of 5.0 g kg−1 at kernel‐hard stage. Spike N concentration increased linearly about 3 g kg−1 from anthesis to kernel‐hard stage. Maximum leaf and stem P concentrations were about 12 and 14 g kg−1, respectively, then decreased curvilinearly to about 2.0 and 0.5 g ka−1, respectively, at kernel‐hard stage. Spike P concentration increased linearly about 0.5 g kg−1 from anthesis to kernel‐hard stage. Leaf peak N content occurred at flag‐leaf‐extension through boot stage and in stems at anthesis. Leaf peak P content occurred at flag leaf through heading and in stems at anthesis. About 71% of the N and 57% of the P in spikes at kernel‐hard stage was translocated from leaves and stems.
Vesicular‐Arbuscular Mycorrhizal Fungus Infestation and Phosphorus Fertigation to Overcome Pepper Stunting after Methyl Bromide Fumigation1
Authors: Haas Jerry H. , Bar‐Yosef B. , Krikun James , Barak R. , Markovitz T. , Kramer S. 
Published: July 2010

AbstractFumigation with methyl bromide (MB) is practiced to control pepper (Capsicum annuum L.) collapse disease, but in P‐sorbing soils the plants grow poorly after fumigation. A field trial was conducted on a high P‐sorbing soil (fossiliferous Typic Torriorthents) to compare P‐fertigation effects on plants grown on fumigated soil subsequently inoculated with Glomus macrocarpum Tul. & Tul. [MB plus vesicular‐arbuscular mycorrhizal fungus (MB+VAMF)] and not inoculated (MB), and on nonfumigated soil (NF). Pepper plants in MB+VAMF were most mycorrhizal, and MB plants the least. Both VAMF inoculation and P fertigation controlled early season stunting. Plants fertigated with 1.3 mmol P L−1 weighed the most 9 weeks after seeding, and among them the MB+VAMF plants were the heaviest. After 9 weeks, all plots were fertigated with 0.6 mmol P L−1. Yields were high (61 to 65 Mg ha−1) where 0.4 mmol P L−1 and more was supplied early in the season, and highest (73 to 74 Mg ha−1) where both P fertigation and VAMF inoculation were used. The presence of significant quantities of mycorrhiza early in the growth season induced the highest percentage of large‐size fruit, thus making P fertilization with VAMF inoculation most beneficial. Phosphorus fertilization recommendations may have to be adjusted when used in conjunction with soil treatments that significantly reduce VAMF populations in the soil. High sorption made it impossible to raise the P concentration in the soil solution to a level that would support maximum nonmycorrhizal‐pepper growth, unless large quantities of P were supplied frequently in the irrigation water.
Phomopsis Seed Decay and Nutrient Accumulation in Soybean under Two Soil Moisture Levels1
Authors: Thomison P. R. , Jeffers D. L. , Schmitthenner A. F. 
Published: July 2010

AbstractInfection of soybean [Glycine max (L.) Merr.] by Phomopsis longicolla Hobbs is associated with physiological changes that occur during senescence. The purpose of this research was to determine the relationship of carbohydrate and mineral nutrient composition of pod tissue to seed infection by P. longicolla during senescence and maturity. Soybean pod nutrient levels were altered by N deficiency and water stress by growing nodulating and non‐nodulating isolines of soybean on a Typic Fragiudalf soil at high and low soil moisture (approximately 100 and 1500 kPa tension, respectively) and with high and low N (75 kg ha−1 and 0 kg ha−1, respectively). Nitrogen fertilizer‐isoline treatments affected plant growth and yield but not seed infection by P. longicolla or seed quality. Physiological maturity occurred 1 to 2 weeks earlier in plants grown under low compared to high soil moisture. Seed produced under low soil moisture exhibited less infection by P. longicolla (18 vs. 58% maximum) and greater germinability (66 vs. 47% minimum) than seed from high moisture soil. Total nonstructural carbohydrates (TNC), N, and P were greater in pod walls from plants grown on high compared to low moisture soil. A lower incidence of P. longicolla in upper nodes (3–32%) compared to lower nodes (13–58%) of plants was associated with higher germination levels, lower K, and greater Ca and TNC levels in pod walls. Decreases in seed germination of 14%, 20 weeks after harvest maturity in 1981, and 7%, 8 weeks after harvest maturity in 1982, were only associated with increased seed infection by P. longicolla (10–15%) in 1982. This difference in P. longicolla between years due to harvest delay was associated with higher levels of TNC in pod walls from high soil moisture treatments in 1982 (86–145 vs. 55–58 g kg−1 dry weight). Reducing seed infection by P. longicolla might be achieved by preventing pod wall accumulation of TNC, N, and P, increasing pod wall accumulation of Ca, and shortening the time from physiological maturity to harvest maturity.
Periodic Shading and the Location and Timing of Branches in Soybean1
Authors: Acock Basil , Acock Mary C. 
Published: July 2010

AbstractAn understanding of the environmental influences on branch initiation and growth is essential for developing mechanistic models that simulate crop behavior. In this study shading was used to determine how limited C availability affects the timing and location of branches in soybean [Glycine max (L.) Merr.] plants grown outdoors. Carbon availability was limited by covering the plants with 66% shade cloth (34% light transmittance) for up to 3 weeks at various times during the seedling stage. Treatments were designated as 000, 100, 110, 111, 011, and 001, where 0 indicates the absence and 1 the presence of shade during each of the 3 weeks from the VC to the V6 stages. The number of branches and the number of nodes on branches were counted at each mainstem node on three observation dates. The total number of nodes on the branches was inversely proportional to the number of weeks in shade. In addition, both timing and location of branch growth on the plant were affected by when the shade treatments were imposed. The cotyledonary node was the preferred site for branch initiation prior to the V2 stage. The unifoliolate node was the preferred site between the V2 and the V6 stages. The number of nodes on trifoliolate branches was affected by the number of branch nodes already present at the cotyledonary and unifoliolate sites. Active branch growth at the lower nodes tended to suppress branch growth at the trifoliolate nodes.