Carl J. Rosen

Research perspective on nitrogen bmp development for potato

Nutrient best management practices (BMPs) are developed to optimize tuber yield and quality, and also to reduce environmental losses of nutrients. Nitrogen (N) management is important both in controlling potato growth and development and in minimizing the risks of groundwater contamination by nitrate and emissions of nitrous oxide, a greenhouse gas. Development of BMPs for N management must consider variation in the magnitude and timing of both N supply and crop N demand. Consequently, these BMPs must reflect differences among potato cultivars, soil properties, cropping systems, water management, and climatic conditions. Despite decades of research, selection of the appropriate rate and timing of fertilizer N application remains a challenging task. A greater understanding of soil N cycling, the development of test-based N recommendation systems, improvements in controlled-release fertilizer technology, and opportunities for spatially variable N management may provide new answers to the old question of “How much N do I apply to my potato crop, at what growth stage, and in what form?”ResumenSe desarrollaron las mejores prácticas de manejo (BMPs) para mejorar el rendimiento y calidad de los tubérculos y también para reducir la pérdida de nutrientes. El manejo del nitrógeno (N) es importante para controlar el crecimiento y desarrollo de la planta y reduce la contaminación del agua del suelo por nitratos y emisiones de ácido nitroso o gas de invernadero. El desarrollo de BMPs para el manejo del N debe considerar la variacián en magnitud y tiempo, tanto del suministro de N como de la demanda de N por el cultivo. Por consiguiente, estos BMPs deben reflejar diferencias entre cultivares de papa, propiedades del suelo, sistemas de cultivo, manejo del agua y condiciones climáticas. A pesar de décadas de investigatión, la selectión de un grado apropiado y momento de aplicación de fertilizante nitrogenado permanecen como tarea discutible. Un mejor entendimiento del ciclo del N, desarrollo de sistemas de recomendación basados en pruebas de N, mejoras en la tecnología de liberatión de fertilizantes controlados y oportunidades para el manejo espacialmente variable del N, puede proporcionar nuevas respuestas a preguntas viejas de “¿Cuanto N debo aplicar a mi cultivo de papa, en que estado de desarrollo y en que forma?”

Antibiotic uptake by vegetable crops from manure-applied soils.

This study quantified the uptake of five antibiotics (chlortetracycline, monensin, sulfamethazine, tylosin, and virginiamycin) by 11 vegetable crops in two different soils that were fertilized with raw versus composted turkey and hog manures or inorganic fertilizer. Almost all vegetables showed some uptake of antibiotics from manure treatments. However, statistical testing showed that except for a few isolated treatments the concentrations of all antibiotics in vegetable tissues were generally less than the limits of quantification. Further testing of the significant treatments showed that antibiotic concentrations in vegetables from many of these treatments were not significantly different than the corresponding concentrations from the fertilizer treatment (matrix effect). All five antibiotic concentrations in the studied vegetables were <10 μg kg(-1). On the basis of the standards for maximum residue levels in animal tissues and suggested maximum daily intake based on body weight, this concentration would not pose any health risk unless one is allergic to that particular antibiotic.

Evaluation of Tuber-Bearing Solanum Species for Nitrogen Use Efficiency and Biomass Partitioning

Modern potato cultivars (Solanum tuberosum L.) require high rates of fertilizer nitrogen (N). This practice is costly and can pose a serious threat to surface and groundwater. Previous evaluation of wild potato germplasm demonstrated the existence of species capable of producing high total biomass under low N conditions, with the ability to make maximum use of added N. Therefore, a two-year field experiment was conducted in 1994 and 1995 to investigate the response of selected wild potato accessions and their hybrids with the haploid USW551 (USW) to low and high N environments. The haploid USW and cultivars Russet Burbank, Red Norland, and Russet Norkotah were also included in the study. Uniform propagules and seedlings from the variousSolanum species were transplanted to a Hubbard loamy sand (Udic Haploboroll) at Becker, Minn. and were subjected to two N treatments: 0 and 225 kg N ha-1. At harvest, total dry biomass of wild and hybrid potato germplasm was equal to or higher than that of the cultivars. However, cultivar biomass partitioning was 1% to roots, 15% to shoots, 0% to fruits, and 84% to tubers, whereas wild potato species partitioned 18% to roots plus nontuberized stolons, 52% to shoots, 23% to fruits, and only 7% to tubers. Hybrids were intermediate, allocating 9% of their biomass to roots plus nontuberized stolons, 39% to shoots, 14% to fruits, and 38% to tubers. Nitrogen use efficiencies for many of the species and crosses were comparable to that for Russet Burbank and greater than those for Red Norland and Russet Norkotah. Of the wild species tested,S. chacoense accessions had the highest biomass accumulation and N uptake efficiencies and may be the best source of germplasm for improving NUE in a potato breeding program.

Direct measurement of petiole sap nitrate in potato to determine crop nitrogen status.

Abstract Rapid determination of crop nitrogen (N) status in the field would facilitate the use of plant tissue testing as a tool for ? management in potato (Solarium tuberosum L.). The Cardy portable nitrate (NO3) meter may provide the means for on‐site determination of petiole sap NO3 (PSN) concentration. Our objective was to establish the relationship between Cardy meter readings of PSN and laboratory measures of petiole dry matter NO3 (PDMN). In a two‐year replicated field study in western Montana, ‘Russet Burbank1 potatoes were grown under a line‐source sprinkler irrigation system with ? fertilization treatments of 0 ? or a rate of 270 kg N/ha applied in four different timing schemes. This created a wide range in crop ? and water status. Petiole samples were collected at five or six dates each year. Subsamples were analyzed for PSN in expressed sap using the Cardy NO3‐specific electrode or for PDMN with a benchtop NO3‐specific electrode after extraction with a solution of aluminum sulfate [A12(SO4)3]....

Effects of Polymer-coated Urea on Nitrate Leaching and Nitrogen Uptake by Potato

Increasing groundwater nitrate concentrations in potato (Solanum tuberosum L.) production regions have prompted the need to identify alternative nitrogen management practices. A new type of polymer-coated urea (PCU) called Environmentally Smart Nitrogen (Agrium, Inc., Calgary, AB) is significantly lower in cost than comparable PCUs, but its potential to reduce nitrate leaching and improve fertilizer recovery has not been extensively studied in potato. In 2006 and 2007, four rates of PCU applied at emergence were compared with equivalent rates of soluble N split-applied at emergence and post-hilling. Additional treatments included a 0 N control, two PCU timing treatments (applied at preplant or planting), and a soluble N fertigation simulation. Nitrate leaching, fertilizer N recovery, N use efficiency (NUE), and residual soil inorganic N were measured. Both 2006 and 2007 were low leaching years. Nitrate leaching with PCU (21.3 kg NO(3)-N ha(-1) averaged over N rates) was significantly lower than with split-applied soluble N (26.9 kg NO(3)-N ha(-1)). The soluble N fertigation treatment resulted in similar leaching as PCU at equivalent N rates. Apparent fertilizer N recovery with PCU (65% averaged over four rates) tended to be higher than split-applied soluble N (55%) at equivalent rates (p = 0.059). Residual soil N and NUE were not significantly affected by N source. Under the conditions of this study, PCU significantly reduced leaching and tended to improved N recovery over soluble N applied in two applications and resulted in similar N recovery and nitrate leaching as soluble N applied in six applications.

Enhanced Efficiency Fertilizers for Improved Nutrient Management: Potato ( Solanum tuberosum )

The improvement of fertilizer efficiency is driven by narrow profit margins, environmental concerns, and resource conservation. Fertile soil is the foundation for food production and successful civilizations; it is developed and maintained through the addition of nutrients lost through harvest. However, nutrient uptake by plants is inherently inefficient and the nutrients remaining in the soil after uptake can cause negative air and water resource impacts. In addition, poor fertilizer efficiency is a waste of natural resources and potentially reduces yields, crop quality, and grower profits. Enhancing fertilizer efficiency in potato is particularly important because relatively high rates of fertilizer and water are necessary to compensate for an inefficient rooting system and extreme sensitivity to deficiencies. Several new fertilizer materials have been designed to enhance fertilizer efficiency. The modes of action of these materials include: (i) slow or controlled release to meet plant need in a more timely fashion; (ii) addition of high charge-density materials that isolate nutrients from interfering elements and compounds; (iii) complexation or chelation of the nutrient to enhance solubility; and (iv) modification of the micro-site pH to enhance nutrient solubility.

Calibration of a petiole sap nitrate test for irrigated ‘russet Burbank’ potato

Abstract Portable electrodes for rapid quantitative determination of nitrate‐N (NO3‐N) in plant sap have recently been developed, thus enabling a quick assessment of the crop nitrogen (N) status. The intent of this study was to provide diagnostic criteria necessary for the interpretation of petiole sap NO3‐N concentrations for potato (Solanum tuberosum L.). Specific objectives were to characterize the relationship between potato petiole sap NO3‐N concentration and petiole NO3‐N determined by conventional dry weight analysis, and to establish NO3‐N sufficiency ranges (NSR) for irrigated potatoes based on sap analyses associated with maximum and 85–95% of maximum yield. A four‐year experiment was conducted on a loamy sand soil (Udic haploboroll) at the Sand Plain Research Farm, Becker, Minn. Ten treatments consisting of various rates and times of N application were evaluated. Recently matured leaves were collected every 10 to 14 days, and petioles were split for sap NO3 and dry tissue NO3 analysis. Two port...

Nutrient supply and neutralizing value of alfalfa stem gasification ash

Ash application influences availabilities of plant micronutrients either directly through addition of its miEnergy generation from biomass is an environmentally sound altercronutrients constituents or indirectly through the modinative to other energy producing technologies. Pilot studies have indicated that alfalfa (Medicago sativa L.) is a suitable feedstock for fication of soil pH. Increased availability of B and Mo energy generation via the gasification process. The resulting ash is a has been reported in soils amended with ash from power potential liming agent and a source of plant nutrients. A growth plants (Codling and Wright, 1998; Hammermeister et al., chamber study was conducted with three soils to evaluate the potential 1998). Clapham and Zibilske (1992) reported that wood use of this ash as a soil amendment. Corn (Zea mays L.) received 13 ash application increased acid-extractable (pH 3, 1 M treatments: control, K and/or P fertilizer, seven ash rates (0.6 to 14.6 g ammonium acetate [NH4OAc]) soil Fe, Zn, Cu, and Mn, ash kg 1 soil), and one ash rate with K or P fertilizer. Soil pH increased but in another study, wood ash decreased extractable with ash application on all soils. Ash application increased ammonium Fe and Al (Naylor and Schmidt, 1986). acetate-exchangeable K, Ca, and Mg, and Olsen P in soil and deModification of soil chemical properties by ash applicreased DTPA-extractable soil Fe, Mn, Ni, and Pb. Averaged across cation has resulted in altered elemental composition of the three soils, slopes of the cations recovered in plant and soil vs. cations applied in the ash were 0.48, 0.21, and 0.22 of total ash K, plants. Wood ash increased the K concentration in corn Ca, and Mg, respectively (r 2 0.97). Ash significantly increased plant and winter wheat (Triticum aestivum L.) in greenhouse K and Mo, and decreased Mg, Mn, and Zn concentration. Tissue P studies (Erich, 1991; Etiegni et al., 1991a) and alfalfa in concentrations were not affected by ash, but increased with P fertilizer. field studies (Meyers and Kopecky, 1998). Wood ash at Phosphorus fertilizer increased plant dry mass (DM), but K fertilizer rates below 20 g kg 1 increased P concentration in wheat did not, thus K did not limit yield. Alfalfa stem gasification ash is a (Etiegni et al., 1991a). Other studies have shown that P potential liming agent, a source of K, and would not lead to excessive availability can increase or decrease in ash-amended soils accumulation of trace elements in soil or plants when applied at rates (Erich, 1991; Voundinkana et al., 1998; Moliner and based on lime or K need. Street, 1982; Elseewi et al., 1980). Application of either coal fly ash or wood ash decreased tissue Zn, Fe, and Mn, and increased B and Mo (Elseewi et al., 1980; FranA has been recognized as an excellent soil amendcis et al., 1985; Naylor and Schmidt, 1989). Application ment since well before Jared Eliot wrote in 1748, of wood-fired boiler ash decreased the concentrations “Ashes is allowed on all hands to be some of the best of Mn and Cu in bean (Phaseolus vulgaris L.) plants dressing or manure for land; it enricheth much and lasts (Krejsl and Scanlon, 1996). These effects on plant microlong; but the misery is we can get but little” (Eliot, 1934; nutrient concentration may have implications for human Carman, 1934). Eliot was referring mainly to wood and or animal health. coal ash, which are available today in large amounts from Plant DM production has increased, decreased, or electricity generation. Effects of coal and wood ash on remained unchanged after coal or wood ash application, soil chemical properties, and on plant yield and eledepending on factors such as type and rate of ash applimental composition have been investigated, and recent cation, plant species, and soil properties. Oat (Avena reviews include Hammermeister et al. (1998) on coal sativa L.) grown in soil amended with 30 Mg ha 1 of ash and Mitchell and Black (1997) and Vance (1996) on wood-fired boiler ash produced significantly higher DM wood ash. than plants grown in nonamended soil, but DM declined The major effects of land application of ash are changes at 50 Mg ha 1 ash (Krejsl and Scanlon, 1996). Wood in soil pH and nutrient availability. Ash has been used ash application had no effect on production of spinach historically and primarily as a liming agent or K source. (Spinacia oleracea L.) in a greenhouse study (Clapham The liming potential or calcium carbonate equivalent and Zibliskie, 1992) nor on wheat yield in a field study (CCE) of ash is dependent both on the type of ash and (Huang et al., 1992). soil chemical properties (Clapham and Zibilske, 1992). In recent years, utilization of herbaceous species as Wood ash is generally rich in oxides, hydroxides, and biomass fuel for electricity generation has been viewed carbonates of Ca, K, and Mg, and contains small quantias an environmentally viable option. Preliminary studies ties of micronutrients (Erich and Ohno, 1992; Mitchell have indicated that alfalfa stems are suitable feedstock and Black, 1997). for energy generation via the gasification process (Wilbur et al., 1998). If the ash from alfalfa gasification can M. Mozaffari, C.J. Rosen, and E.A. Nater, Dep. of Soil, Water, and be utilized as a soil amendment, then economic viability Climate, 439 Borlaug Hall, 1991 Upper Buford Circle, Univ. of Minnesota. St. Paul, MN 55108; M.P. Russelle, USDA–ARS U.S. Dairy and public acceptance of this alternative energy source Forage Research Center (Minnesota Cluster) and Dep. of Soil, Water, may increase. Chemical characterization has indicated and Climate, 439 Borlaug Hall, Univ. of Minnesota. St. Paul, MN that alfalfa ash is a potential liming agent, its macronu55108; Joint contribution of the Minnesota Agric. Exp. Stn. and the trient content is equivalent to a 1-1-10 fertilizer, and it USDA-ARS. Received 8 Aug. 2000. *Corresponding author (crosen@ soils.umn.edu). Abbreviations: CCE, calcium carbonate equivalent; DM, dry matter; ICP-AES, inductively coupled plasma atomic emission spectroscopy. Published in Soil Sci. Soc. Am. J. 66:171–178 (2002).

Phosphorus runoff from turfgrass as affected by phosphorus fertilization and clipping management.

Phosphorus enrichment of surface water is a concern in many urban watersheds. A 3-yr study on a silt loam soil with 5% slope and high soil test P (27 mg kg(-1) Bray P1) was conducted to evaluate P fertilization and clipping management effects on P runoff from turfgrass (Poa pratensis L.) under frozen and nonfrozen conditions. Four fertilizer treatments were compared: (i) no fertilizer, (ii) nitrogen (N)+potassium (K)+0xP, (iii) N+K+1xP, and (iv) N+K+3xP. Phosphorus rates were 21.3 and 63.9 kg ha(-1) yr(-1) the first year and 7.1 and 21.3 kg ha(-1) yr(-1) the following 2 yr. Each fertilizer treatment was evaluated with clippings removed or clippings recycled back to the turf. In the first year, P runoff increased with increasing P rate and P losses were greater in runoff from frozen than nonfrozen soil. In year 2, total P runoff from the no fertilizer treatment was greater than from treatments receiving fertilizer. This was because reduced turf quality resulted in greater runoff depth from the no fertilizer treatment. In year 3, total P runoff from frozen soil and cumulative total P runoff increased with increasing P rate. Clipping management was not an important factor in any year, indicating that returning clippings does not significantly increase P runoff from turf. In the presence of N and K, P fertilization did not improve turf growth or quality in any year. Phosphorus runoff can be reduced by not applying P to high testing soils and avoiding fall applications when P is needed.

Response of russet norkotah clonal selections to nitrogen fertilization

The low vine vigor and high N requirement of Russet Norkotah may lead to N loss and groundwater contamination on coarse-textured soils. Recent clonal selections from Texas have produced strains that have larger and stronger vines, which may alter N requirements. This twoyear study examined the N use efficiency (NUE), yield, and quality of Russet Norkotah strain selections fertilized with different N levels on a Hubbard loamy sand in central Minnesota. The selections, Texas Norkotah Strain (TXNS) 112, TXNS 223, and TXNS 278 were grown with standard Russet Norkotah under irrigated conditions and received total N levels of 28, 112, 224, or 336 kg ha-1. Total, marketable, and large (>340 g) tuber yields increased linearly (P>0.05) with rate of N application in 1998 but not in 1997. The genotype main effect was not significant for any of the tuber yield parameters measured based on fresh weight. Vine, tuber, and total dry biomass yields were 116%, 5.8%, and 13.2%, respectively, higher with the selections than Russet Norkotah. Harvest index (HI), or the proportion of total dry matter partitioned to tubers, was 7% greater for Russet Norkotah than the TXNS selections, reflecting the larger vine growth of the selections. The selections accumulated significantly higher N in the vines (0.113 kg kg-1 N) than the standard clone (0.053 kg kg-1 N) as N rate increased from 28 to 336 kg ha-1, and the difference between the selections and the standard clone was larger at higher N rates than at lower N rates. Russet Norkotah partitioned 10% more N to tubers than did the TXNS selections, reflecting the difference in HI between the standard cultivar and its clones. Nitrogen recovered from fertilizer N applied in addition to the 28 kg ha-1 starter N (NUE28) averaged 36% and varied little with genotype, N rate, or cropping year. Biomass accumulation from similar N additions (AUE), however, was significantly higher for the selections than Russet Norkotah at 112 kg N ha-1 in 1997 only. At low N rate (112 kg ha-1), the selections had higher physiological use efficiency (PUE28) (mean 45.9 g g1) than Russet Norkotah (25.9 g g1). Results from this study demonstrate that, although N recovery was similar for the four genotypes, the Texas Norkotah strains produced greater biomass than Russet Norkotah per kg N applied at low rate in 1997 and per kg of fertilizer N absorbed by the plant in both years. However, under the conditions of this study, higher biomass of the selections did not translate into a marketable yield advantage over the standard cultivar.ResumenEl poco vigor del follaje y los altos requerimientos de N de “Russet Norkotah” pueden conducir a una pérdida de N y a contaminación por agua subterránea en suelos de textura gruesa. Recientes selecciones clonales de Texas han producido razas con un follaje más numeroso y vigoroso, el cual puede alterar los requerimientos de N. Durante dos años de estudios se examinó la eficiencia en el uso de N (EUN), los rendimientos y la calidad de la selección de razas de Russet Norkotah fertilizadas con diferentes niveles de N en un suelo franco arenoso de Hubbard en Minnesota central. Las selecciones, Texas Norkotah Strain (TXNS) 112, TXNS 223, y TXNS 278, crecieron con Russet Norkotah estándar bajo condiciones de irrigación y recibieron niveles totales de N de 28, 112, 224 o 336 kg ha-1. Los rendimientos comerciales totales y el largo (>340 g) de los tubérculos se incrementó linealmente (P<0.05) con las tasas de N aplicadas en 1998 pero no con las de 1997. El efecto princpipal en el genotipo no fue significativo en ninguno de los parámetros de rendimiento del tubérculo medidos en base al peso en fresco. Los rendimientos totales de follaje, tubérculo y biomasa seca fueron 116%, 5.8% y 13.2% respectivamente, más altos que las selecciones de Russet Norkotah. El índice de cosecha (IC), o la proporción de cantidad total de materia seca dividida entre los tubérculos fue 7% mayor para Russet Norkotah que para las selecciones TXNS, reflejando el mayor crecimiento de follaje de las selecciones. Las selecciones acumularon N en cantidad significativamente mayor en los follajes (0.113 kg kg-1 N) que en el clon estándar (0.053 kg kg-1 N) a medida que la tasa de N fue incrementándose de 28 a 336 kg ha-1, y la diferencia entre las selecciones y el clon estándar fue más grande a tasas más altas de N que a bajas tasas de N. Russet Norkotah repartió 10% más N a los tubérculos que las selecciones TXNS, reflejando la diferencia en el IC entre el cultivar estándar y sus clones. El nitrógeno recuperado del fertilizante de N aplicado en adición a los 28 kg ha-1 iniciales de N (EUN28) promedió 36% y varió en pequeña cantidad con genotipo, tasa de N o año agrícola. La acumulación de biomasa de adiciones similares de N (EAN) fue, sin embargo, significativamente mayor en el caso de las selecciones que en Russet Norkotah a 112 kg N ha-1 solamente en 1997. A bajas tasas de N (112 kg ha-1), las selecciones presentaron mayor eficiencia fisiológica de uso (EFU28) (lo que significa 45.9 g g-1) que la Russet Norkotah (25.9 g g-1). Los resultados de este estudio demuestran que, aunque la recuperación de N fue similar en los 4 genotipos, la raza Texas Norkotah prodigo una mayor biomasa que Russet Norkotah por Kg N aplicado a bajas tasas en 1997 y por kg de fertilizante de N absorbido por la planta en ambos años. Sin embargo, bajo las condiciones de este estudio, una mayor biomasa de las selecciones no se tradujo en un rendimiento comercial más ventajoso sobre el cultivar estándar.