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PRODUCTION PAPERS

Sugarbeet Growth as Affected by Wheat Residues and Nitrogen Fertilization

^a Soil Sci. Dep., North Dakota State Univ., Fargo, ND 58102
^b Univ. of Minnesota, Northwest Res. and Outreach Cent., 2900 University Ave., Crookston, MN 56716

^* Corresponding author (John.Moraghan{at}ndsu.nodak.edu).

Received for publication October 3, 2002.

	ABSTRACT

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Little is known about how low-N, mature wheat (Triticum aestivum L.) straw and high-N, postharvest volunteer wheat growth from the previous year influence N fertilizer requirements for sugarbeet (Beta vulgaris L.). This 2-yr field study examined how wheat straw (3.36 and 6.72 Mg ha^-1; 3.5 g N kg^-1 in 2000 and 8.0 g N kg^-1 in 2001), preflowering wheat residues (2.1 to 4.2 Mg ha^-1; 29.1 to 44.7 g N kg^-1), and urea (0 to 225 kg N ha^-1), fall-applied and incorporated, affected sugarbeet growth. The previous crop was wheat, and wheat straw was removed from the experimental sites subsequent to the grain harvest. Sugar yields were decreased 10% by application of 3.36 Mg ha^-1 straw and 25% by 6.72 Mg ha^-1 straw in 2000. The corresponding 2001 sugar decreases were 13 and 19%, respectively. Application of 45 kg ha^-1 urea N largely overcame the detrimental effect from 3.36 Mg ha^-1 straw but only partially overcame the detrimental effect from 6.72 Mg ha^-1 straw in both experiments. Plant N, petiole NO₃–N, and soil inorganic N (NH₄–N + NO₃–N) data all indicated that incorporation of low-N mature wheat straw decreased availability of soil N, probably due to net N immobilization associated with straw decomposition. In contrast to mature wheat straw, application and incorporation of high-N, preflowering wheat residues increased recoverable sugar yields in both years. Removal of straw after a wheat crop reduces the N fertilizer requirement for a subsequent sugarbeet crop.

	INTRODUCTION

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THE RED RIVER VALLEY of Minnesota and North Dakota is the main sugarbeet–growing area in North America. Sugarbeet, planted in the spring, often follows spring wheat from the previous year. Wheat straw, which normally contains between 3 and 8 g N kg^-1, is either completely incorporated, partially incorporated using various conservation tillage practices, or removed subsequent to the grain harvest. Removal of straw is becoming a more common practice, a consequence of a commercial market for straw in board manufacture. Fall volunteer wheat growth, depending on fall moisture availability, soil inorganic N level, date of the first killing frost, and lack of tillage, can sometimes accumulate in excess of 100 kg ha^-1 organic N before freeze-up (Wilkinson and Schroer, 1966; Moraghan, 1995). Such volunteer wheat growth may contain in excess of 20 g N kg^-1.

Nitrogen fertilization of sugarbeet in the Red River Valley is based on a soil test for NO₃–N during autumn or spring (Lamb et al., 2001). The fertilizer is generally fall-applied and is usually in close contact with any incorporated residues. Little is known about how wheat straw and volunteer wheat residues influence availability of soil inorganic N and sugarbeet growth. Adequate soil inorganic N is essential for early sugarbeet growth since N deficiency delays leaf canopy development and initiation of sugar accumulation (Moraghan, 1972).

According to Tinker (1983), addition of organic N residues complicates the assessment of soil mineral N in sugarbeet production because their rate of breakdown is difficult to predict and the degree of release of mineral N depends on their composition and on the rate of mineralization. Plowed-in straw sometimes results in sugarbeet plants with symptoms of N deficiency early in the growing season (Draycott, 1972). James et al. (1967) suggested, because of problems associated with N availability, that sugarbeet should not be planted following a wheat crop where heavy straw residues were plowed down. According to Smith et al. (1973), about 7.5 kg of additional fertilizer N per ton (metric) of wheat straw, with N concentrations of 3.6 and 4.7 g kg^-1, was required for sugarbeet in Idaho to compensate for N immobilization during residue decomposition. In one study (Allison et al., 1992), straw incorporation had no effect on sugar yield at the recommended rate of N fertilizer application. However, sugar yield and N uptake were reduced by incorporation of straw when the rate of N fertilizer was low. In a follow-up study (Allison and Hetschkun, 1995), the influence of straw removal from each of five preceding small-grain crops on the N fertilizer requirement of a subsequent sugarbeet crop was determined. The optimal fertilizer rate was reduced from about 120 to 100 kg N ha^-1 as a result of straw removal. The best predictors for N mineralization from cover crops, and presumably volunteer wheat crops, were residue C/N ratios and the reciprocal of residue N concentration (Quemada and Cabrera, 1995).

The objective of our study was to determine the influence of wheat straw and wheat volunteer growth on N fertilizer requirement for sugarbeet. Due to uncertainty about obtaining suitable volunteer growth from farmers' fields, wheat was planted in early August and used instead of volunteer growth.

	MATERIALS AND METHODS

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The influence of urea N; nondried, preflowering, chopped wheat residues; and mature wheat straw on growth of following year sugarbeet crops was studied in separate experiments in 2000 and 2001 at Crookston, MN. Spring wheat was grown on the experimental sites the previous year before sugarbeet. Residual wheat straw was removed from the experimental sites after the grain harvests. The fertilizer and crop residue treatments shown in Table 1 were spread by hand on the soil surface and incorporated in the upper 15 cm of soil with a rototiller on 11 October in both 1999 and 2000. The 12 treatments were replicated six times and arranged in randomized complete blocks. The soil at the experimental sites was a Wheatville loam (coarse silty over clayey, mixed, over smectic, superactive, frigid Aeric Calciaquolls).

Spring wheat was planted in early August of 1999 and 2000 to obtain preflowering residues between Zadok growth stages 32 and 37 (Zadok et al., 1974) for the 2000 and 2001 experiments. The vegetative growth was cut at a height of about 5 cm and chopped into pieces varying between about 6 and 12 cm with a self-propelled forage harvester. Two residues differing in N concentration were included in 2000; one type of residue at two rates of application was used in 2001 (Table 1). The moist, preflowering residues were mixed for homogeneity with pitchforks and subsampled for moisture and N analyses; weighed quantities were applied to relevant field plots within 2 h of harvest. To ensure application rates of about 2 and 4 Mg ha^-1 residue on a dry matter basis, preapplication estimates of residue moisture contents were obtained with a silage moisture meter.

The sugarbeet cultivar VDH 66283 was planted in 2000 on 25 April and in 2001 on 4 May. The plots were 3.3 m wide and 10.5 m long; six sugarbeet rows spaced 56 cm apart were planted in each plot. The plants were thinned to a population of about 88070 plants ha^-1 in early June. Twenty-five of the thinned sugarbeet plants (two- to six-leaf stage) from the 2001 experiment were cut at the cotyledonary node on 8 June, washed, oven-dried, weighed, ground to pass a sieve with 0.5-mm openings, and analyzed for total N. No sampling at thinning was done in 2000.

Tops were harvested in both experiments from 3.7-m lengths of Row 5 in late September. The moist tops were weighed, chopped, and mixed. Subsamples were then taken, weighed, dried, reweighed, ground to pass a sieve with 0.5-mm openings, and analyzed for total N. Storage roots from 10.5 m of both Rows 3 and 4 were mechanically harvested and weighed on 28 September for the 2000 experiment and 27 September for the 2001 experiment. Subsamples of roots were weighed, washed, reweighed, and analyzed by the American Crystal Sugar Company, East Grand Forks, MN, for recoverable sugar by a procedure based on an impurity index approach (Carruthers and Oldfield, 1961). Brei (macerated roots) was retained, frozen with dry ice, freeze-dried, ground, and analyzed for moisture and total N.

Fourteen recently mature leaves were harvested from Row 2 in both experiments at about 14-d intervals after the majority of plots had leaf area indices greater than about 1.5. Petioles were cut into 1-cm pieces, dried, ground to pass a sieve with 0.5-mm openings, redried, and analyzed for NO₃–N.

Check plots were sampled for soil NO₃–N on 28 Oct. 1999 for the 2000 experiment and on 19 Oct. 2000 for the 2001 experiment. Three cores were taken in 15-cm increments to 30 cm and in 30-cm increments between 30 and 180 cm from each check plot. Relevant depth increments from the three cores were composited in the field, placed in polyethylene bags, and transferred on dry ice to the laboratory for storage overnight at 2°C. The soils were then air-dried within 24 h in a greenhouse, ground to pass a sieve with 2-mm openings, and analyzed for NO₃–N.

To determine the effect of 6.72 Mg ha^-1 straw on soil inorganic N in the 0- to 30-cm depth during May and early June, twelve 30-cm cores in 15-cm increments, each 1.3 cm in diameter, were taken between Rows 2 and 3 of the check and the straw-treated plots. Soil cores from a sampled plot were composited and frozen until required for analysis. The thawed samples were mixed for uniformity and subsampled for moisture, NO₃–N, and NH₄–N analyses.

Experimentally determined soil bulk density data were used to convert soil NO₃–N concentration data to a kilogram-per-hectare basis. Six cores, each 3.45 cm in diameter, were taken from the experimental areas in the autumn before planting and used for determination of bulk density in relevant soil depth increments below 15 cm. Bulk density for the 0 to 15 cm depth was determined whenever a plot was sampled for soil NO₃–N. A 15-cm-long metal cylinder, 6.98 cm in diameter, was inserted in triplicate into the surface soil for this measurement.

Plant samples were analyzed for total N by a Kjeldahl procedure with a salicylic acid modification to include NO₃–N (Nelson and Sommers, 1973). Petiole NO₃–N was extracted with 1 M KCl from oven-dried samples and, after suitable dilution, determined by a Cd reduction procedure (USEPA, 1979). Soil NO₃–N and NH₄–N were extracted with 2 M KCl. Soil NH₄–N was determined by a MgO distillation procedure (Bremner, 1965). Soil NO₃–N was determined by the previously described Cd reduction procedure. Sodium bicarbonate extractable P and extractable K for soils at the experimental sites were determined by standard procedures (Anonymous, 1988).

	RESULTS

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Soil Inorganic Nitrogen
Experimental sites with less than 40 kg ha^-1 NO₃–N in the 0- to 60-cm soil depth were needed for this study; this requirement was met (Table 2). Sugarbeet normally responds to N fertilizer in the Red River Valley region when mid- to late-October soil NO₃–N levels are less than about 112 kg ha^-1 in the upper 60 cm of soil (Lamb et al., 2001).

Quantitative data pertaining to growth and N accumulation by plant tops harvested at the two- to six-leaf growth stage are given in Table 4. Mature straw reduced seedling growth at both the 3.36 and 6.72 Mg ha^-1 rates of application. Addition of 45 kg ha^-1 urea N with straw had no effect on the growth suppression with the higher straw rate and had only a small beneficial effect with the low straw rate. The two rates of straw application reduced N accumulation in plant tops. Preflowering wheat residues, unlike the mature straw treatments, did not suppress seedling growth and N accumulation.

Root and Sugar Yields
Root and sugar yields in the 2000 and 2001 experiments were not greatly affected by N fertilization when straw was removed from the research sites (Table 5). In contrast, N fertilization increased root and sugar yields when straw treatments were applied. Mature straw treatments decreased root and sugar yields relative to those of the check (no N applied). Application of 45 kg ha^-1 urea N with 3.36 Mg ha^-1 mature straw largely eliminated root yield decreases. For example, application of 3.36 Mg ha^-1 straw compared with the check treatment decreased sugar yields by 10% in 2000 and 13% in 2001. The yield decreases were only 3% in both years when 45 kg ha^-1 urea N was also added with 3.36 Mg ha^-1 mature straw. Application of 45 kg ha^-1 urea N with 6.72 Mg ha^-1 mature straw was less efficacious in overcoming the pronounced yield reductions with this straw treatment. For instance, compared with the check treatment, application of 6.72 Mg ha^-1 mature straw decreased recoverable sugar yields by 25% in 2000 and by 19% in 2001. With 45 kg ha^-1 urea N, 6.72 Mg ha^-1 mature straw decreased sugar yields by 16% in 2000 and by 7% in 2001.

Plant Nitrogen and Petiole Nitrate
Total N in tops plus storage roots at the September harvests was increased by N fertilizer in the absence of added straw and by the high rate of preflowering wheat residues (Table 6). Application of mature straw resulted in the lowest N accumulation by harvested plants in both years.

	DISCUSSION

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During the spring thaw, surface soils in the region have moisture contents above the field capacity until the frost layer lower in the soil profile disappears. Losses of soil NO₃–N due to denitrification can occur under such conditions (Malhi and Nyborg, 1986). Although low temperatures during thawing would slow denitrification (Bailey and Beauchamp, 1973), incorporation of straw would increase the potential for denitrification losses of soil NO₃–N (Avalakki et al., 1995).

Application of 45 kg ha^-1 urea N did not completely overcome the detrimental effect of 6.72 Mg ha^-1 mature straw on sugar yield. Did this rate of wheat straw, in addition to causing N immobilization, restrict sugarbeet growth due to the presence or production of phytotoxins during decomposition (McCalla and Haskins, 1964)? No definitive answer to this question can be given. According to Kimber (1973), phytotoxicity effects in contrast to N immobilization effects are more pronounced when straw is not incorporated. In contrast, Lovett and Jessop (1982) found phytotoxicity was increased when crop residues were incorporated into soil rather than being left on the surface.

The residual soil NO₃ test in the Red River Valley is especially valuable for identifying farm fields high in soil NO₃–N that are unsuitable for sugarbeet production. Sugarbeet storage roots produced on such soils are generally low in sugar concentration and high in impurities (Draycott, 1972). Applications of N fertilizer is recommended for sugarbeet fields in the region that contain less than about 112 kg ha^-1 NO₃–N in the upper 60 cm of soil (Lamb et al., 2001). However, recommended fertilizer rates are subject to potential error due to N mineralization and immobilization associated with residue decomposition.

Since the two experimental sites contained about 34 kg ha^-1 NO₃–N in the upper 60 cm of soil, about 80 kg ha^-1 urea N should have been required for optimal sugar yields based on the currently used soil test (Lamb et al., 2001). With straw removal, the soil test obviously overestimated N fertilizer requirement. Also, there is a need to consider straw management when making N fertilizer recommendations for sugarbeet. Decomposition of straw left on the soil surface, and presumably partially incorporated straw, is much slower than completely buried straw (Schomberg et al., 1994). Consequently, the cropping year requirement for N fertilizer to overcome N immobilization possibly may be reduced if residues are not fully buried.

The reason why high-N, preflowering wheat residues increased sugar yield is not obvious. These residues increased plant N uptake, apparently the result of increased N mineralization. However, urea N also increased N uptake but was not as efficacious as the preflowering residues for increasing sugar yield. The beneficial effect may simply be due to an increased, relatively continuous supply of mineralized N in the upper 15 cm of soil, a zone particularly important for early-season uptake of N by sugarbeet roots. Alternatively, the sugarbeet plants possibly had access to larger quantities of NH₄–N during the growing season with the high N, preflowering residue treatments than with the urea treatments. Some plants have superior growth with a mixed NH₄–NO₃ inorganic N supply (Cox and Reisenhauer, 1973). The preflowering residue had no effect on P concentration in shoots of the two- to six-leaf seedlings in 2001 (data not presented).

Incorporation of high-N crop residues is known to increase soil N mineralization (Moraghan and Smith, 1996; Sims et al., 2002) and cause an overestimation of N fertilizer requirements based on preplanting levels of soil NO₃–N. However, if appreciable volunteer growth occurs after soil sampling for residual NO₃, the efficacy of the soil NO₃–N test for N fertilizer recommendations may be reduced. All the soil NO₃–N assimilated during volunteer growth is unlikely to be mineralized and available for sugarbeet plants during leaf canopy development early in the growing season.

	ACKNOWLEDGMENTS

 
The authors express their appreciation to Kevin Horsager for technical assistance and to Pam Loose for assistance in preparation of the manuscript.

	REFERENCES

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• Allison, M.F., and H.M. Hetschkun. 1995. Five years of straw incorporation and its effect on growth, yield and nitrogen nutrition of sugarbeet (Beta vulgaris). J. Agric. Sci. 125:61–68.
• Allison, M.F., K.W. Jaggard, and P.J. Last. 1992. Effects of straw incorporation on the yield, nitrogen fertilizer and insecticide requirement of sugar beet (Beta vulgaris). J. Agric. Sci. 118:199–206.
• Anonymous. 1988. Recommended chemical soil test procedures for the north central region. Bull. 499 (rev.). North Dakota Agric. Exp. Stn., Fargo.
• Avalakki, U.K., W.M. Strong, and P.G. Saffigna. 1995. Measurements of gaseous emissions from denitrification of applied nitrogen-15: II. Effects of temperature and added straw. Aust. J. Soil Res. 33:89–99.
• Bailey, L.D., and E.G. Beauchamp. 1973. Effects of temperature on NO₃– and NO₂– reduction, nitrogenous gas production, and redox potential in a saturated soil. Can. J. Soil Sci. 53:213–218.
• Black, A.L., and L.L. Reitz. 1972. Phosphorus and nitrate-nitrogen immobilization by wheat straw. Agron. J. 64:782–785.[Abstract/Free Full Text]
• Bremner, J.M. 1965. Inorganic forms of nitrogen. p. 1179–1237. In C.A. Black et al. (ed.) Methods of soil analysis. Part 2. 1st ed. Agron. Monogr. 9. ASA, Madison, WI.
• Carruthers, A., and J.F.T. Oldfield. 1961. Methods for the assessment of beet quality. Int. Sugar J. 53:137–139.
• Cox, W.J., and H.M. Reisenhauer. 1973. Growth and ion uptake by wheat supplied nitrogen as nitrate, or ammonium, or both. Plant Soil 38:363–380.
• Draycott, A.P. 1972. Sugar-beet nutrition. John Wiley & Sons, New York.
• James, D.W., C.E. Nelson, and A.R. Halvorson. 1967. Soil testing for residual nitrate as a guide for nitrogen fertilization of sugar beets. Circ. 480. Washington Agric. Exp. Stn., Pulman.
• Kimber, R.W.L. 1973. Phytotoxicity from plant residues: III. The relative effects of toxins and nitrogen immobilization on the germination and growth of wheat. Plant Soil 38:543–555.
• Lamb, J.A., A.L. Sims, L.J. Smith, and G.W. Rehm. 2001. Fertilizing sugarbeet in Minnesota and North Dakota. Ext. Bull. FO-07715-C. Univ. of Minnesota, St. Paul.
• Lovett, J.V., and R.S. Jessop. 1982. Effects of residues of crop plants on germination and early growth of wheat. Aust. J. Agric. Res. 33:909–916.
• Malhi, S.S., and M. Nyborg. 1986. Increase in mineral N in soils during winter and loss of mineral N during early spring in north central Alberta. Can. J. Soil Sci. 66:397–409.
• McCalla, T.M., and F.A. Haskins. 1964. Phytotoxic substances from soil microorganisms and crop residues. Bact. Rev. 27:181–207.
• Moraghan, J.T. 1972. Water use by sugarbeets in a semiarid environment as influenced by population and nitrogen fertilizer. Agron. J. 64:759–762.[Abstract/Free Full Text]
• Moraghan, J.T. 1995. Volunteer small-grain growth in 1994. Sugarbeet Res. Ext. Rep. 25:227.
• Moraghan, J.T., and L. Smith. 1996. Nitrogen in sugarbeet tops and the growth of a subsequent wheat crop. Agron. J. 88:521–526.[Abstract/Free Full Text]
• Nelson, D.W., and L.E. Sommers. 1973. Determination of total nitrogen in plant material. Agron. J. 65:109–112.[Abstract/Free Full Text]
• Quemada, M., and M.L. Cabrera. 1995. Carbon and nitrogen mineralized from leaves and stems of four cover crops. Soil Sci. Soc. Am. J. 59:471–477.[Abstract/Free Full Text]
• Schomberg, H.H., J.L. Steiner, and P.W. Unger. 1994. Decomposition and nitrogen dynamics of crop residues: Residue quality and water effects. Soil Sci. Soc. Am. J. 58:372–381.[Abstract/Free Full Text]
• Sims, A.L., J.T. Moraghan, and L.J. Smith. 2002. Spring wheat response to fertilizer nitrogen following a sugar beet crop varying in canopy color. Precis. Agric. 3:283–295.
• Smith, J.H., C.L. Douglas, and M.J. LeBaron. 1973. Influence of straw application rates, plowing dates, and nitrogen application rates on yield and chemical composition of sugarbeets. Agron. J. 65:797–800.[Abstract/Free Full Text]
• Tinker, P.B. 1983. Dynamics of nitrogen in soils suitable for sugar beet. p. 87–97. In Symposium: Nitrogen and sugar-beet, Palais des Congrès, Brussels, Belgium. 16–17 Feb. 1983. Institut International de Recherches Betteravières (IIRB), Brussels, Belgium.
• USEPA. 1979. Methods for chemical analysis of water and wastes. EPA-6004–79–020. USEPA, Cincinnati, OH.
• Wilkinson, G.E., and F.W. Schroer. 1966. Water, nitrogen removal by cover crops on fallow. N.D. Farm Res. 23(6):4–7.
• Zadok, C.J., T.T. Chang, and C.F. Konzak. 1974. A decimal code for the growth stages of cereals. Weed Sci. 14:415–421.

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moraghan, J. T. Articles by Smith, L. J. Search for Related Content PubMed Articles by Moraghan, J. T. Articles by Smith, L. J. Agricola Articles by Moraghan, J. T. Articles by Smith, L. J. Related Collections Crop Rotation Systems Sugarbeet Nitrogen