A comparison of the effects of prilled urea, used alone or with a nitrification or urease inhibitor, with those of 'Nitro-Chalk' on winter oil-seed rape.

Rodgers, G. A., Penny, A. and Hewitt, M. V. 1986. A comparison of the effects of prilled urea, used alone or with a nitrification or urease inhibitor, with those of 'Nitro-Chalk' on winter oil-seed rape. The Journal of Agricultural Science. 106 (3), pp. 515-526. https://doi.org/10.1017/S0021859600063401

Related outputs

Symposium: the Broadbalk long-term experiment at Rothamsted: what has it told us about weeds?

A - Papers appearing in refereed journals

Moss, S. R., Storkey, J., Cussans, J. W., Perryman, S. A. M. and Hewitt, M. V. 2004. Symposium: the Broadbalk long-term experiment at Rothamsted: what has it told us about weeds? Weed Science. 52, pp. 864-873. https://doi.org/10.1614/WS-04-012R1

The classic long-term experiments at Rothamsted: what have they told us about weeds?

C2 - Non-edited contributions to conferences

Moss, S. R. and Hewitt, M. V. 2002. The classic long-term experiments at Rothamsted: what have they told us about weeds? Abstracts Annual Meeting of the Weed Science Society of America, Reno, 10-13 February 2002 . pp. Abstract 198

A comparison of management regimes for one-year rotational set-aside within a sequence of winter wheat crops, and of growing wheat without interruption. 1. Effects on soil mineral nitrogen, grain yield and quality

A - Papers appearing in refereed journals

Bacon, E. T. G., Hewitt, M. V. and Shepherd, C. E. 1998. A comparison of management regimes for one-year rotational set-aside within a sequence of winter wheat crops, and of growing wheat without interruption. 1. Effects on soil mineral nitrogen, grain yield and quality. The Journal of Agricultural Science. 130, pp. 377-388. https://doi.org/10.1017/S0021859698005437

Peat - a valuable resource

C1 - Edited contributions to conferences/learned societies

Johnston, A. E., Hewitt, M. V., Poulton, P. R. and Lane, P. W. 1997. Peat - a valuable resource. Wilson, W. S. and Hayes, M. H. B. (ed.) Humic substances in soils, peats and waters: health and environmental aspects . Royal Society of Chemistry (RSC), Cambridge. pp. 368-383

The LINK-IFS Project - the effect of crop rotations and cropping systems on Carabidae

C1 - Edited contributions to conferences/learned societies

Holland, J. M., Drysdale, A., Hewitt, M. V. and Turley, D. 1996. The LINK-IFS Project - the effect of crop rotations and cropping systems on Carabidae. Rotations and Cropping Systems. Aspects of Applied Biology 47 .

Predator populations and the influence of crop type and preliminary impact of integrated farming systems

C1 - Edited contributions to conferences/learned societies

Holland, J. M., Hewitt, M. V. and Drysdale, A. D. 1994. Predator populations and the influence of crop type and preliminary impact of integrated farming systems. Arable Farming under CAP Reform. Aspects of Applied Biology 40 . pp. 217-224

Effects of one to six year old ryegrass-clover leys on soil nitrogen and on the subsequent yields and fertilizer nitrogen requirements of the arable sequence winter wheat, potatoes, winter wheat, winter beans (Vicia faba ) grown on a sandy loam soil

A - Papers appearing in refereed journals

Johnston, A. E., McEwen, J., Lane, P. W., Hewitt, M. V., Poulton, P. R. and Yeoman, D. P. 1994. Effects of one to six year old ryegrass-clover leys on soil nitrogen and on the subsequent yields and fertilizer nitrogen requirements of the arable sequence winter wheat, potatoes, winter wheat, winter beans (Vicia faba ) grown on a sandy loam soil. The Journal of Agricultural Science. 122 (1), pp. 73-89. https://doi.org/10.1017/S0021859600065825

Effects of previous crop, sowing date, and winter and spring applications of nitrogen on the growth, nitrogen uptake and yield of winter wheat

A - Papers appearing in refereed journals

Milford, G. F. J., Penny, A., Prew, R. D., Darby, R. J. and Todd, A. D. 1993. Effects of previous crop, sowing date, and winter and spring applications of nitrogen on the growth, nitrogen uptake and yield of winter wheat. The Journal of Agricultural Science. 121 (1), pp. 1-12. https://doi.org/10.1017/S0021859600076735

The effect of cultivation and plant establishment on nitrogen conservation on set-aside land

C1 - Edited contributions to conferences/learned societies

Hewitt, M. V., Webster, C. P. and Bacon, E. T. G. 1992. The effect of cultivation and plant establishment on nitrogen conservation on set-aside land. Set-aside. British Crop Protection Council Monograph.

A comparison of the effects of single or multiple spring applications of prilled urea or 'Nitro-chalk' to winter oilseed rape (Brassica napus)

A - Papers appearing in refereed journals

Darby, R. J. and Hewitt, M. V. 1990. A comparison of the effects of single or multiple spring applications of prilled urea or 'Nitro-chalk' to winter oilseed rape (Brassica napus). The Journal of Agricultural Science. 115 (3), pp. 363-368. https://doi.org/10.1017/S0021859600075808

Effects of field beans, fallow, lupins, oats, oilseed rape, peas, ryegrass, sunflowers and wheat on nitrogen residues in the soil and on the growth of a subsequent wheat crop.

A - Papers appearing in refereed journals

McEwen, J., Darby, R. J., Hewitt, M. V. and Yeoman, D. P. 1989. Effects of field beans, fallow, lupins, oats, oilseed rape, peas, ryegrass, sunflowers and wheat on nitrogen residues in the soil and on the growth of a subsequent wheat crop. The Journal of Agricultural Science. 115 (2), pp. 209-219. https://doi.org/10.1017/S0021859600075146

Uptake of foliar-applied urea by winter-wheat (Triticum aestivum) the influence of application time and the use of a new 15N technique.

A - Papers appearing in refereed journals

Powlson, D. S., Poulton, P. R., Moller, N. E., Hewitt, M. V., Penny, A. and Jenkinson, D. S. 1989. Uptake of foliar-applied urea by winter-wheat (Triticum aestivum) the influence of application time and the use of a new 15N technique. Journal of the Science of Food and Agriculture. 48 (4), pp. 429-440. https://doi.org/10.1002/jsfa.2740480405

Contrast between sandy and clay soils in the effects of various factors on the growth, nitrogen uptake and yield of winter wheat in three years.

A - Papers appearing in refereed journals

Thorne, G. N., Welbank, P. J., Widdowson, F. V., Penny, A. and Todd, A. D. 1988. Contrast between sandy and clay soils in the effects of various factors on the growth, nitrogen uptake and yield of winter wheat in three years. The Journal of Agricultural Science. 110 (1), pp. 119-140. https://doi.org/10.1017/S0021859600079764

Amounts of NO3-N and NH4-N in soil, from autumn to spring, under winter wheat and their relationship to soil type, sowing date, previous crop and N uptake at Rothamsted, Woburn and Saxmundham, 1979-85.

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A., Darby, R. J., Bird, E. and Hewitt, M. V. 1987. Amounts of NO3-N and NH4-N in soil, from autumn to spring, under winter wheat and their relationship to soil type, sowing date, previous crop and N uptake at Rothamsted, Woburn and Saxmundham, 1979-85. The Journal of Agricultural Science. 108 (1), pp. 73-95. https://doi.org/10.1017/S0021859600064145

Tests of nitrification and of urease inhibitors, when applied with either solid or aqueous urea, on grass grown on a light sandy soil.

A - Papers appearing in refereed journals

Rodgers, G. A., Penny, A., Widdowson, F. V. and Hewitt, M. V. 1987. Tests of nitrification and of urease inhibitors, when applied with either solid or aqueous urea, on grass grown on a light sandy soil. The Journal of Agricultural Science. 108 (1), pp. 109-117. https://doi.org/10.1017/S0021859600064170

Recovery of 15N-labelled urea applied to the foliage of winter wheat.

A - Papers appearing in refereed journals

Powlson, D. S., Poulton, P. R., Penny, A. and Hewitt, M. V. 1987. Recovery of 15N-labelled urea applied to the foliage of winter wheat. Journal of the Science of Food and Agriculture. 41 (3), pp. 195-203. https://doi.org/10.1002/jsfa.2740410302

Biological nitrogen transformations in soil after repeated application of nitrification inhibitors.

A - Papers appearing in refereed journals

Rodgers, G. A. 1987. Biological nitrogen transformations in soil after repeated application of nitrification inhibitors. Zentralblatt fur Mikrobiologie. 142 (5), pp. 343-348. https://doi.org/10.1016/S0232-4393(87)80078-1

Some factors affecting the growth and yield of winter wheat grown as a third cereal with much or negligible take-all

A - Papers appearing in refereed journals

Prew, R. D., Beane, J., Carter, N., Church, B. M., Dewar, A. M., Lacey, J., Penny, A., Plumb, R. T., Thorne, G. N. and Todd, A. D. 1986. Some factors affecting the growth and yield of winter wheat grown as a third cereal with much or negligible take-all. The Journal of Agricultural Science. 107 (3), pp. 639-671. https://doi.org/10.1017/S0021859600069811

The relationship of soil mineral NO3-N with NO3-N concentration, and of fertilizer -N with the amount of nitrogen taken up by winter wheat, in experiments testing nitrogen fertilizer in combination with aphicide and fungicides, from 1980 to 1982.

A - Papers appearing in refereed journals

Darby, R. J., Widdowson, F. V., Bird, E. and Hewitt, M. V. 1986. The relationship of soil mineral NO3-N with NO3-N concentration, and of fertilizer -N with the amount of nitrogen taken up by winter wheat, in experiments testing nitrogen fertilizer in combination with aphicide and fungicides, from 1980 to 1982. The Journal of Agricultural Science. 106, pp. 497-507. https://doi.org/10.1017/S0021859600063383

Potency of nitrification inhibitors following their repeated application to soil.

A - Papers appearing in refereed journals

Rodgers, G. A. 1986. Potency of nitrification inhibitors following their repeated application to soil. Biology And Fertility Of Soils. 2, pp. 105-108. https://doi.org/10.1007/BF00257587

Results from experiments on winter barley measuring the effects of amount and timing of nitrogen and some other factors on the yield and nitrogen content of the grain

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Jenkyn, J. F. 1986. Results from experiments on winter barley measuring the effects of amount and timing of nitrogen and some other factors on the yield and nitrogen content of the grain. The Journal of Agricultural Science. 106 (3), pp. 537-549. https://doi.org/10.1017/S0021859600063425

Effects of soil and fertilizer P on yields of potatoes, sugar beet, barley and winter wheat on a sandy clay loam soil at Saxmundham, Suffolk

A - Papers appearing in refereed journals

Johnston, A. E., Lane, P. W., Mattingly, G. E. G., Poulton, P. R. and Hewitt, M. V. 1986. Effects of soil and fertilizer P on yields of potatoes, sugar beet, barley and winter wheat on a sandy clay loam soil at Saxmundham, Suffolk. The Journal of Agricultural Science. 106 (1), pp. 155-167. https://doi.org/10.1017/S0021859600061864

Nitrification in acid tea soils and a neutral grassland soil: Effects of nitrification inhibitors and inorganic salts

A - Papers appearing in refereed journals

Wickramasinghe, K. N., Rodgers, G. A. and Jenkinson, D. S. 1985. Nitrification in acid tea soils and a neutral grassland soil: Effects of nitrification inhibitors and inorganic salts. Soil Biology and Biochemistry. 17 (2), pp. 249-252. https://doi.org/10.1016/0038-0717(85)90123-3

Some factors limiting the growth and yield of winter-wheat and their variation in 2 seasons

A - Papers appearing in refereed journals

Prew, R. D., Church, B. M., Dewar, A. M., Lacey, J., Magan, N., Penny, A., Plumb, R. T., Thorne, G. N., Todd, A. D. and Williams, T. D. 1985. Some factors limiting the growth and yield of winter-wheat and their variation in 2 seasons. The Journal of Agricultural Science. 104 (1), pp. 135-162. https://doi.org/10.1017/s0021859600043070

Tests of amounts and times of application of nitrogen and of sequential sprays of aphicide and fungicides on winter wheat, following either beans or wheat, and the effects of take-all (Gaeumannomyces graminis var. tritici ), on two varieties at Saxmundham, Suffolk 1980-3

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A., Gutteridge, R. J., Darby, R, J. and Hewitt, M. V. 1985. Tests of amounts and times of application of nitrogen and of sequential sprays of aphicide and fungicides on winter wheat, following either beans or wheat, and the effects of take-all (Gaeumannomyces graminis var. tritici ), on two varieties at Saxmundham, Suffolk 1980-3. The Journal of Agricultural Science. 105, pp. 97-122. https://doi.org/10.1017/S0021859600055775

Effects of nitrification inhibitors on uptakes of mineralised nitrogen and on yields of winter cereals grown on sandy soil after ploughing old grassland

A - Papers appearing in refereed journals

Rogers, G. A., Penny, A. and Hewitt, M. V. 1985. Effects of nitrification inhibitors on uptakes of mineralised nitrogen and on yields of winter cereals grown on sandy soil after ploughing old grassland. Journal of the Science of Food and Agriculture. 36 (10), pp. 915-924. https://doi.org/10.1002/jsfa.2740361003

Mineralization of dicyandiamide, labelled with 15N, in acid soils

A - Papers appearing in refereed journals

Rodgers, G. A., Wickramasinghe, K. N. and Jenkinson, D. S. 1985. Mineralization of dicyandiamide, labelled with 15N, in acid soils. Soil Biology and Biochemistry. 17 (2), pp. 253-254. https://doi.org/10.1016/0038-0717(85)90124-5

The effect of sowing date and of leaching on soil nitrogen supply for winter wheat at Rothamsted and Woburn 1981

B - Book chapters etc edited externally

Widdowson, F. V., Penny, A., Darby, R. J. and Bird, E. 1984. The effect of sowing date and of leaching on soil nitrogen supply for winter wheat at Rothamsted and Woburn 1981. in: In : The nitrogen requirement of cereals : proceedings of a conference organised by ADAS September 1982 London HMSO. pp. 125-128

Inhibition of soil urease activity by aminocresols

A - Papers appearing in refereed journals

Rodgers, G. A. 1984. Inhibition of soil urease activity by aminocresols. Plant and Soil. 79 (1), pp. 155-157. https://doi.org/10.1007/bf02182151

Comparisons between the establishment, growth and yield of winter-wheat on 3 clay soils, in experiments testing nitrogen-fertilizer in combination with aphicide and fungicides, from 1980 to 1982

A - Papers appearing in refereed journals

Darby, R. J., Widdowson, F. V. and Hewitt, M. V. 1984. Comparisons between the establishment, growth and yield of winter-wheat on 3 clay soils, in experiments testing nitrogen-fertilizer in combination with aphicide and fungicides, from 1980 to 1982. The Journal of Agricultural Science. 103 (DEC), pp. 595-611. https://doi.org/10.1017/s0021859600043720

Field estimation of ammonia volatilisation from 15N-labelled urea fertiliser

A - Papers appearing in refereed journals

Rodgers, G. A. and Pruden, G. 1984. Field estimation of ammonia volatilisation from 15N-labelled urea fertiliser. Journal of the Science of Food and Agriculture. 35 (12), pp. 1290-1293. https://doi.org/10.1002/jsfa.2740351204

Comparison of the effects of aqueous and of prilled urea, used alone or with urease or nitrification inhibitors, with those of ''Nitro-Chalk'' on ryegrass leys

A - Papers appearing in refereed journals

Rodgers, G. A., Widdowson, F. V., Penny, A. and Hewitt, M. V. 1984. Comparison of the effects of aqueous and of prilled urea, used alone or with urease or nitrification inhibitors, with those of ''Nitro-Chalk'' on ryegrass leys. The Journal of Agricultural Science. 103 (3), pp. 671-685. https://doi.org/10.1017/S0021859600063401

Assessing the need of maincrop potatoes for late nitrogen by using isobutylidene di-urea by injecting nitrification inhibitors with aqueous N fertilizers and by dividing dressings of "Nitro-chalk"

A - Papers appearing in refereed journals

Penny, A., Addiscott, T. M. and Widdowson, F. V. 1984. Assessing the need of maincrop potatoes for late nitrogen by using isobutylidene di-urea by injecting nitrification inhibitors with aqueous N fertilizers and by dividing dressings of "Nitro-chalk". The Journal of Agricultural Science. 103 (3), pp. 577-585. https://doi.org/10.1017/S0021859600043707

Experiments with solid and liquid N-fertilizers and fungicides on winter wheat at Saxmundham, Suffolk, 1976–9

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Jenkyn, J. F. 1983. Experiments with solid and liquid N-fertilizers and fungicides on winter wheat at Saxmundham, Suffolk, 1976–9. The Journal of Agricultural Science. 100 (1), pp. 163-173. https://doi.org/10.1017/s0021859600032573

Effects of several nitrification inhibitors, when injected with aqueous urea, on yields and nitrogen recoveries of ryegrass leys

A - Papers appearing in refereed journals

Rodgers, G. A., Widdowson, F. V., Penny, A. and Hewitt, M. V. 1983. Effects of several nitrification inhibitors, when injected with aqueous urea, on yields and nitrogen recoveries of ryegrass leys. The Journal of Agricultural Science. 101 (DEC), pp. 637-656. https://doi.org/10.1017/s0021859600038673

Effect of dicyandiamide on ammonia volatilization from urea in soil

A - Papers appearing in refereed journals

Rodgers, G. A. 1983. Effect of dicyandiamide on ammonia volatilization from urea in soil. Fertilizer Research. 4 (4), pp. 361-367. https://doi.org/10.1007/bf01054009

Effects of eight factors on the growth and nutrient-uptake of winter-wheat and on the incidence of pests and diseases

A - Papers appearing in refereed journals

Prew, R. D., Church, B. M., Dewar, A. M., Lacey, J., Penny, A., Plumb, R. T., Thorne, G. N., Todd, A. D. and Williams, T. D. 1983. Effects of eight factors on the growth and nutrient-uptake of winter-wheat and on the incidence of pests and diseases. The Journal of Agricultural Science. 100 (2), pp. 363-382. https://doi.org/10.1017/s0021859600033529

Use of nitrification inhibitors to improve recovery of mineralised nitrogen by winter wheat

A - Papers appearing in refereed journals

Rodgers, G. A. and Ashworth, J. 1982. Use of nitrification inhibitors to improve recovery of mineralised nitrogen by winter wheat. Journal of the Science of Food and Agriculture. 33 (12), pp. 1219-1226. https://doi.org/10.1002/jsfa.2740331208

Results from the Woburn Reference Experiment, III. Yields of the Crops and Recoveries of N, P, K, and Mg from Manures and Soil, 1975-79

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Hewitt, M. V. 1982. Results from the Woburn Reference Experiment, III. Yields of the Crops and Recoveries of N, P, K, and Mg from Manures and Soil, 1975-79. Rothamsted Experimental Station Report. 1981 (2), pp. 5-21.

Use of nitrification inhibitors to improve recovery of mineralized nitrogen by winter-wheat

A - Papers appearing in refereed journals

Rodgers, G. A. and Ashworth, J. 1982. Use of nitrification inhibitors to improve recovery of mineralized nitrogen by winter-wheat. Journal of the Science of Food and Agriculture. 33 (12), pp. 1219-1226. https://doi.org/10.1002/jsfa.2740331208

Results from factorial experiments testing amounts and times of granular N-fertilizer, late sprays of liquid N-fertilizer and fungicides to control mildew and brown rust on two varieties of spring barley at Saxmundham, Suffolk 1975–8

A - Papers appearing in refereed journals

Widdowson, F. V., Jenkyn, J. F. and Penny, A. 1982. Results from factorial experiments testing amounts and times of granular N-fertilizer, late sprays of liquid N-fertilizer and fungicides to control mildew and brown rust on two varieties of spring barley at Saxmundham, Suffolk 1975–8. The Journal of Agricultural Science. 99 (2), pp. 377-390. https://doi.org/10.1017/s0021859600030173

Results from an experiment on permanent grass evaluating the cumulative effects of aqueous urea, injected alone or with a nitrification inhibitor, with those of nitro-chalk

A - Papers appearing in refereed journals

Ashworth, J., Widdowson, F. V., Penny, A., Gibbs, A. J., Hodgkinson, R. A. and Hewitt, M. V. 1982. Results from an experiment on permanent grass evaluating the cumulative effects of aqueous urea, injected alone or with a nitrification inhibitor, with those of nitro-chalk. The Journal of Agricultural Science. 98 (FEB), pp. 141-154. https://doi.org/10.1017/s0021859600041216

Bacteriostatic action of nitrification inhibitors

A - Papers appearing in refereed journals

Rodgers, G. A. and Ashworth, J. 1982. Bacteriostatic action of nitrification inhibitors. Canadian Journal Of Microbiology. 28 (10), pp. 1093-1100. https://doi.org/10.1139/m82-163

The compatibility of the nitrification inhibitor dicyandiamide with injected anhydrous ammonia

A - Papers appearing in refereed journals

Ashworth, J. and Rodgers, G. A. 1981. The compatibility of the nitrification inhibitor dicyandiamide with injected anhydrous ammonia. Canadian journal of soil science. 61 (2), pp. 461-463. https://doi.org/10.4141/cjss81-051

Results from the Rothamsted Reference Experiment II. Yields of the Crops and Recoveries of N, P and K from Manures and Soil, 1971-75

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Bird, E. 1980. Results from the Rothamsted Reference Experiment II. Yields of the Crops and Recoveries of N, P and K from Manures and Soil, 1971-75. Rothamsted Experimental Station Report. 1979 (2), pp. 63-75.

Results from the Rothamsted reference experiment II Yields of the crops and recoveries of N, P and K from manures and soil 1971-1975

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Bird, E. 1980. Results from the Rothamsted reference experiment II Yields of the crops and recoveries of N, P and K from manures and soil 1971-1975. Rothamsted Experimental Station Report. 1979 (2), pp. 63-75.

Recovery of nitrifier populations from inhibition by nitrapyrin or CS2

A - Papers appearing in refereed journals

Rodgers, G. A., Ashworth, J. and Walker, N. 1980. Recovery of nitrifier populations from inhibition by nitrapyrin or CS2. Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrankheiten und Hygiene. Zweite Naturwissenschaftliche Abteilung: Mikrobiologie der Landwirtschaft, der Technologie und des Umweltschutzes. 135 (6), pp. 477-483. https://doi.org/10.1016/S0323-6056(80)80066-8

Multifactorial experimentation on continuous winter-wheat grown in sandy clay soil at Saxmundham, Suffolk

A - Papers appearing in refereed journals

Widdowson, F. V., Johnston, A. E. and Penny, A. 1980. Multifactorial experimentation on continuous winter-wheat grown in sandy clay soil at Saxmundham, Suffolk. The Journal of Agricultural Science. 94 (FEB), pp. 155-170. https://doi.org/10.1017/s002185960002801x

An experiment begun in 1958 measuring effects of n, p and k fertilizers on yield and n, p and k contents of grass .2. Residual effects on arable crops, 1968-76

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Williams, R. J. B. 1980. An experiment begun in 1958 measuring effects of n, p and k fertilizers on yield and n, p and k contents of grass .2. Residual effects on arable crops, 1968-76. The Journal of Agricultural Science. 95 (DEC), pp. 583-595. https://doi.org/10.1017/s0021859600087992

An experiment begun in 1958 measuring effects of n, p and k fertilizers on yield and n, p and k contents of grass .1. Effects during 1964-7

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Williams, R. J. B. 1980. An experiment begun in 1958 measuring effects of n, p and k fertilizers on yield and n, p and k contents of grass .1. Effects during 1964-7. The Journal of Agricultural Science. 95 (DEC), pp. 575-582. https://doi.org/10.1017/s0021859600087980

Evaluation of potential substrates to monitor respiratory nitrate reductase-activity in soils

A - Papers appearing in refereed journals

Rodgers, G. A. 1980. Evaluation of potential substrates to monitor respiratory nitrate reductase-activity in soils. Journal of Soil Science. 31 (2), pp. 387-395. https://doi.org/10.1111/j.1365-2389.1980.tb02088.x

The effects of injecting nitrapyrin (n-serve), carbon disulphide or trithiocarbonates, with aqueous ammonia, on yield and percent-n of grass

A - Papers appearing in refereed journals

Ashworth, J., Penny, A., Widdowson, F. V. and Briggs, G. G. 1980. The effects of injecting nitrapyrin (n-serve), carbon disulphide or trithiocarbonates, with aqueous ammonia, on yield and percent-n of grass. Journal of the Science of Food and Agriculture. 31 (3), pp. 229-237. https://doi.org/10.1002/jsfa.2740310303

Results from the Woburn Reference Experiment II. Yields of the Crops and Recoveries of N, P, K and Mg from Manures and Soil, 1970-74

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1979. Results from the Woburn Reference Experiment II. Yields of the Crops and Recoveries of N, P, K and Mg from Manures and Soil, 1970-74. Rothamsted Experimental Station Report. 1978 (2), pp. 67-82.

Xanthates as inhibitors of fertilizer nitrogen transformation in soil

A - Papers appearing in refereed journals

Ashworth, J., Rodgers, G. A. and Briggs, G. G. 1979. Xanthates as inhibitors of fertilizer nitrogen transformation in soil. Chemistry & Industry. (3), pp. 90-92.

Spring top-dressings of ‘Nitro-Chalk’ and late sprays of a liquid N-fertilizer and a broad spectrum fungicide for consecutive crops of winter wheat at Saxmundham, Suffolk

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Jenkyn, J. F. 1978. Spring top-dressings of ‘Nitro-Chalk’ and late sprays of a liquid N-fertilizer and a broad spectrum fungicide for consecutive crops of winter wheat at Saxmundham, Suffolk. The Journal of Agricultural Science. 90 (3), pp. 509-516. https://doi.org/10.1017/s0021859600056021

Longevity of sodium, potassium and magnesium fertilizer residual effects on yield and composition of ryegrass grown on a sandy soil

A - Papers appearing in refereed journals

Bolton, J. and Penny, A. 1978. Longevity of sodium, potassium and magnesium fertilizer residual effects on yield and composition of ryegrass grown on a sandy soil. The Journal of Agricultural Science. 91 (3), pp. 693-699. https://doi.org/10.1017/s0021859600060093

Dry deposition of atmospheric ammonia at Rothamsted in 1976 and 1977

A - Papers appearing in refereed journals

Rodgers, G. A. 1978. Dry deposition of atmospheric ammonia at Rothamsted in 1976 and 1977. The Journal of Agricultural Science. 90 (3), pp. 537-542. https://doi.org/10.1017/s0021859600056069

Results from an experiment on permanent grass evaluating aqueous ammonia and aqueous urea, injected in bands either 30 or 60 cm apart

A - Papers appearing in refereed journals

Penny, A., Widdowson, F. V. and Ashworth, J. 1977. Results from an experiment on permanent grass evaluating aqueous ammonia and aqueous urea, injected in bands either 30 or 60 cm apart. The Journal of Agricultural Science. 88 (APR), pp. 319-331. https://doi.org/10.1017/s0021859600034821

Results from two sets of experiments with spring barley, first comparing injected with broadcast nitrogen granules, second comparing injected and combine-drilled NPK solutions with broadcast NPK granules

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1977. Results from two sets of experiments with spring barley, first comparing injected with broadcast nitrogen granules, second comparing injected and combine-drilled NPK solutions with broadcast NPK granules. The Journal of Agricultural Science. 88 (FEB), pp. 35-45. https://doi.org/10.1017/s0021859600033748

Nitrogenase activity in nostoc-muscorum - recovery from desiccation

A - Papers appearing in refereed journals

Rodgers, G. A. 1977. Nitrogenase activity in nostoc-muscorum - recovery from desiccation. Plant and Soil. 46 (3), pp. 671-674. https://doi.org/10.1007/bf00015929

Experiments evaluating aqueous ammonia, aqueous urea and a solution of ammonium-nitrate and urea as nitrogenous fertilizers for winter-wheat

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1977. Experiments evaluating aqueous ammonia, aqueous urea and a solution of ammonium-nitrate and urea as nitrogenous fertilizers for winter-wheat. The Journal of Agricultural Science. 89 (OCT), pp. 415-424. https://doi.org/10.1017/s0021859600028343

Results from two barley experiments at Saxmundham, Suffolk, measuring effects of the fungicide benodanil on three varieties, given three amounts of nitrogen at two times 1973–4

A - Papers appearing in refereed journals

Widdowson, F. V., Jenkyn, J. F. and Penny, A. 1976. Results from two barley experiments at Saxmundham, Suffolk, measuring effects of the fungicide benodanil on three varieties, given three amounts of nitrogen at two times 1973–4. The Journal of Agricultural Science. 86 (2), pp. 271-280. https://doi.org/10.1017/s0021859600054721

Results from experiments measuring effects of large amounts of an npk fertilizer on yield, tuber size and n, p and k contents of 3 potato varieties

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1975. Results from experiments measuring effects of large amounts of an npk fertilizer on yield, tuber size and n, p and k contents of 3 potato varieties. The Journal of Agricultural Science. 85 (DEC), pp. 515-525. https://doi.org/10.1017/s0021859600062390

Results from two experiments with winter wheat, comparing top-dressings of a liquid N-fertilizer either alone or with added herbicide or mildew fungicide or both, and of 'Nitro-Chalk' without or with herbicide or fungicide or both

A - Papers appearing in refereed journals

Penny, A. and Jenkyn, J. F. 1975. Results from two experiments with winter wheat, comparing top-dressings of a liquid N-fertilizer either alone or with added herbicide or mildew fungicide or both, and of 'Nitro-Chalk' without or with herbicide or fungicide or both. The Journal of Agricultural Science. 85 (3), pp. 533-539. https://doi.org/10.1017/s0021859600062419

Results from experiments with winter-wheat, spring barley and grass, comparing a liquid N-fertilizer either alone or with added herbicide and top-dressings of nitro-chalk without or with herbicide sprayed alone

A - Papers appearing in refereed journals

Penny, A. and Freeman, S. C. R. 1974. Results from experiments with winter-wheat, spring barley and grass, comparing a liquid N-fertilizer either alone or with added herbicide and top-dressings of nitro-chalk without or with herbicide sprayed alone. The Journal of Agricultural Science. 83 (3), pp. 511-529. https://doi.org/10.1017/s0021859600027003

Results from experiments measuring effects of large amounts of fertilizer and of farmyard manure on main-crop potatoes grown in sandy soil at Woburn, Bedfordshire

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Flint, R. C. 1974. Results from experiments measuring effects of large amounts of fertilizer and of farmyard manure on main-crop potatoes grown in sandy soil at Woburn, Bedfordshire. The Journal of Agricultural Science. 82 (FEB), pp. 117-127. https://doi.org/10.1017/s0021859600050292

Yields and N, P and K Contents of the Crops Grown in the Rothamsted Reference Experiment, 1956-70,

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1973. Yields and N, P and K Contents of the Crops Grown in the Rothamsted Reference Experiment, 1956-70, . Rothamsted Experimental Station Report. 1972 (2), pp. 111-130.

Results from experiments comparing aqueous and anhydrous ammonia with nitrochalk for grass cut for silage

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Flint, R. C. 1973. Results from experiments comparing aqueous and anhydrous ammonia with nitrochalk for grass cut for silage. The Journal of Agricultural Science. 81 (DEC), pp. 465-480. https://doi.org/10.1017/s0021859600086524

Results from the Woburn Reference Experiment, 1960-1969

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1972. Results from the Woburn Reference Experiment, 1960-1969. Rothamsted Experimental Station Report. 1971 (2), pp. 69-94.

Results from an experiment comparing aqueous ammonia with Nitro-Chalk for grazed grass

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Flint, R. C. 1972. Results from an experiment comparing aqueous ammonia with Nitro-Chalk for grazed grass. The Journal of Agricultural Science. 79 (2), pp. 341-348. https://doi.org/10.1017/S0021859600032330

Results from barley experiments comparing aqueous ammonia and aqueous urea with ammonium nitrate, and also liquid with granular NPK fertilizers

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Flint, R. C. 1972. Results from barley experiments comparing aqueous ammonia and aqueous urea with ammonium nitrate, and also liquid with granular NPK fertilizers. The Journal of Agricultural Science. 79 (2), pp. 349-361. https://doi.org/10.1017/S0021859600032342

Evaluation of phosphate fertilizers. III. Immediate and residual values of potassium metaphosphate and magnesium ammonium phosphate for potatoes, radishes, barley and ryegrass

A - Papers appearing in refereed journals

Mattingly, G. E. G., Penny, A. and Blakemore, M. 1971. Evaluation of phosphate fertilizers. III. Immediate and residual values of potassium metaphosphate and magnesium ammonium phosphate for potatoes, radishes, barley and ryegrass. The Journal of Agricultural Science. 76, pp. 131-141. https://doi.org/10.1017/S0021859600015677

The Agdell experiment - Estimates of the P and K accumulated from fertiliser dressings given between 1848-1951 their recovery by grass between 1958 and 1970 and their effect on the response by grass to new dressings of P and K

A - Papers appearing in refereed journals

Johnston, A. E. and Penny, A. 1971. The Agdell experiment - Estimates of the P and K accumulated from fertiliser dressings given between 1848-1951 their recovery by grass between 1958 and 1970 and their effect on the response by grass to new dressings of P and K. Rothamsted Experimental Station Report. 1970 (2), pp. 38-68.

The Effects of Partially Sterilising Agricultural Soils With Formalin, and of Applying Nitrogen Fertilisers, on the Yields and N Contents of Spring and Winter Wheat, of Barley and of Grass

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1970. The Effects of Partially Sterilising Agricultural Soils With Formalin, and of Applying Nitrogen Fertilisers, on the Yields and N Contents of Spring and Winter Wheat, of Barley and of Grass. Rothamsted Experimental Station Report. 1969 (Part 2), pp. 113-134. https://doi.org/10.23637/ERADOC-1-34866

Anhydrous ammonia-yields and recoveries by spring wheat.

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1970. Anhydrous ammonia-yields and recoveries by spring wheat. Anhydrous Ammonia. Proceedings of a Symposium on Aspects of its Technology and Use as a Fertilizer.. pp. 61-66.

The effects of three crops and of the N fertilizer given to them on the yield of following barley

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1970. The effects of three crops and of the N fertilizer given to them on the yield of following barley. The Journal of Agricultural Science. 74 (3), pp. 511-522. https://doi.org/10.1017/S0021859600017639

The value of residues from long-period manuring at Rothamsted and Woburn IV The value to arable crops of residues accumulated from superphosphate

A - Papers appearing in refereed journals

Johnston, A. E., Warren, R. G. and Penny, A. 1970. The value of residues from long-period manuring at Rothamsted and Woburn IV The value to arable crops of residues accumulated from superphosphate. Rothamsted Experimental Station Report. 1969 (Part 2), pp. 39-68. https://doi.org/10.23637/ERADOC-1-34863

The value of residues from long-period manuring at Rothamsted and Woburn V The value to arable crops of residues accumulated from potassium fertilizers

A - Papers appearing in refereed journals

Johnston, A. E., Warren, R. G. and Penny, A. 1970. The value of residues from long-period manuring at Rothamsted and Woburn V The value to arable crops of residues accumulated from potassium fertilizers. Rothamsted Experimental Station Report. 1969 (Part 2), pp. 69-90. https://doi.org/10.23637/ERADOC-1-34864

Effects on barley and kale of NPK fertilizers containing differing proportions of urea and ammonium nitrate, and either triple superphosphate or mono-urea phosphate

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1969. Effects on barley and kale of NPK fertilizers containing differing proportions of urea and ammonium nitrate, and either triple superphosphate or mono-urea phosphate. The Journal of Agricultural Science. 73 (1), pp. 125-132. https://doi.org/10.1017/S0021859600024205

Results of an experiment at Rothamsted testing farmyard manure and N, P and K fertilizers on five arable crops and permanent grass III. Yields 1961–1965

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1968. Results of an experiment at Rothamsted testing farmyard manure and N, P and K fertilizers on five arable crops and permanent grass III. Yields 1961–1965. The Journal of Agricultural Science. 70 (1), pp. 53-58. https://doi.org/10.1017/S0021859600017184

The effects of potassium and magnesium fertilizers on yield and composition of successive crops of ryegrass, clover, sugar beet, potatoes, kale and barley on sandy soil at Woburn

A - Papers appearing in refereed journals

Bolton, J. and Penny, A. 1968. The effects of potassium and magnesium fertilizers on yield and composition of successive crops of ryegrass, clover, sugar beet, potatoes, kale and barley on sandy soil at Woburn. Journal of the Science of Food and Agriculture. 70 (3), pp. 303-311. https://doi.org/10.1017/S0021859600012624

Evaluation of phosphate fertilizers I. Immediate value of dicalcium phosphate, nitrophosphates, Gafsa rock phosphate, basic slag and potassium metaphosphate for barley and ryegrass

A - Papers appearing in refereed journals

Mattingly, G. E. G. and Penny, A. 1968. Evaluation of phosphate fertilizers I. Immediate value of dicalcium phosphate, nitrophosphates, Gafsa rock phosphate, basic slag and potassium metaphosphate for barley and ryegrass. The Journal of Agricultural Science. 70, pp. 131-138.

Results of an experiment at Woburn testing farmyard manure and N, P and K fertilizers on five arable crops and a long ley: I. Yields

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1967. Results of an experiment at Woburn testing farmyard manure and N, P and K fertilizers on five arable crops and a long ley: I. Yields. The Journal of Agricultural Science. 68 (1), pp. 95-102. https://doi.org/10.1017/S0021859600017901

Experiments comparing the effects on yields of potatoes of three methods of applying three amounts of NPK fertilizer and the residual effects on following winter wheat

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1967. Experiments comparing the effects on yields of potatoes of three methods of applying three amounts of NPK fertilizer and the residual effects on following winter wheat. The Journal of Agricultural Science. 69 (2), pp. 247-257. https://doi.org/10.1017/S0021859600018657

Experiments measuring effects of ammonium and nitrate fertilizers, with and without sodium and potassium, on spring barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1967. Experiments measuring effects of ammonium and nitrate fertilizers, with and without sodium and potassium, on spring barley. The Journal of Agricultural Science. 69 (2), pp. 197-207. https://doi.org/10.1017/S0021859600018591

Results of an experiment at Woburn testing farmyard manure and N, P and K fertilizers on five arable crops and on a long ley: II. N, P and K removed by the crops

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1967. Results of an experiment at Woburn testing farmyard manure and N, P and K fertilizers on five arable crops and on a long ley: II. N, P and K removed by the crops. The Journal of Agricultural Science. 68 (2), pp. 293-300. https://doi.org/10.1017/S0021859600016361

The value of urea nitrate and urea phosphate as nitrogen fertilizers for grass and barley

A - Papers appearing in refereed journals

Gasser, J. K. R. and Penny, A. 1967. The value of urea nitrate and urea phosphate as nitrogen fertilizers for grass and barley. The Journal of Agricultural Science. 67 (1), pp. 139-146. https://doi.org/10.1017/S0021859600016555

An experiment measuring effects of N, P and K fertilizers on yield and N, P and K contents of grazed grass

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1966. An experiment measuring effects of N, P and K fertilizers on yield and N, P and K contents of grazed grass. The Journal of Agricultural Science. 67 (1), pp. 121-128. https://doi.org//10.1017/S0021859600067654

Experiments measuring the residual effects of nitrogen fertilizers

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1965. Experiments measuring the residual effects of nitrogen fertilizers. The Journal of Agricultural Science. 65 (2), pp. 195-200. https://doi.org/10.1017/S002185960008391X

An experiment measuring effects of N, P and K fertilizers on yield and N, P and K contents of grass

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1965. An experiment measuring effects of N, P and K fertilizers on yield and N, P and K contents of grass. The Journal of Agricultural Science. 64 (1), pp. 93-100. https://doi.org/10.1017/S0021859600010522

Experiments comparing concentrated and dilute NPK fertilizers and four nitrogen fertilizers on a range of crops

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1965. Experiments comparing concentrated and dilute NPK fertilizers and four nitrogen fertilizers on a range of crops. The Journal of Agricultural Science. 65 (1), pp. 45-55. https://doi.org/10.1017/S002185960008535X

An experiment comparing responses to nitrogen fertilizer of four grass species Part II Residual effects in wheat and barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1964. An experiment comparing responses to nitrogen fertilizer of four grass species Part II Residual effects in wheat and barley. Experimental husbandry. 11, pp. 22-30.

Experiments comparing liquid and solid fertilisers for grass and kale

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1964. Experiments comparing liquid and solid fertilisers for grass and kale. Experimental husbandry. 10, pp. 97-100.

Experiments comparing broadcast and combine drilled dressings of several NPK fertilizers for spring barley

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1964. Experiments comparing broadcast and combine drilled dressings of several NPK fertilizers for spring barley. Experimental husbandry. 14, pp. 83-97.

Experiments testing P and K fertilizers on lucerne 1952-1957

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1964. Experiments testing P and K fertilizers on lucerne 1952-1957. Experimental husbandry. 10, pp. 39-45.

Side-placing urea and other nitrogen fertilizers for spring barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1964. Side-placing urea and other nitrogen fertilizers for spring barley. The Journal of Agricultural Science. 62 (1), pp. 73-82. https://doi.org/10.1017/S0021859600059803

An experiment comparing responses to nitrogen fertilizer of four grass species

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1963. An experiment comparing responses to nitrogen fertilizer of four grass species. Experimental husbandry. 9, pp. 28-36.

Experiments comparing yield, and residual effects on winter wheat, of 1-year clover, rye-grass and clover-rye-grass leys

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1963. Experiments comparing yield, and residual effects on winter wheat, of 1-year clover, rye-grass and clover-rye-grass leys. The Journal of Agricultural Science. 61 (3), pp. 397-408. https://doi.org/10.1017/S0021859600018128

Results of an experiment at Rothamsted testing farmyard manure and N, P and K fertilizers on five arable crops I. Yields

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Cooke, G. W. 1963. Results of an experiment at Rothamsted testing farmyard manure and N, P and K fertilizers on five arable crops I. Yields. The Journal of Agricultural Science. 60 (3), pp. 347-352. https://doi.org/10.1017/S002185960001193X

Experiments with nitrogen and potash on potatoes

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1962. Experiments with nitrogen and potash on potatoes. Experimental husbandry. 8, pp. 30-39.

An experiment comparing urea-formaldehyde fertilizer with nitro-chalk for Italian ryegrass

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1962. An experiment comparing urea-formaldehyde fertilizer with nitro-chalk for Italian ryegrass. The Journal of Agricultural Science. 59 (2), pp. 263-268. https://doi.org/10.1017/S002185960001529X

Applying nitrogen fertilizers for spring barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1961. Applying nitrogen fertilizers for spring barley. The Journal of Agricultural Science. 56 (1), pp. 39-47. https://doi.org/10.1017/S0021859600023789

Autumn nitrogen for winter wheat

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1961. Autumn nitrogen for winter wheat. The Journal of Agricultural Science. 57 (3), pp. 329-334. https://doi.org/10.1017/S0021859600049297

Experiments with nitrogen and potash on barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Williams, R. J. B. 1961. Experiments with nitrogen and potash on barley. The Journal of Agricultural Science. 57 (1), pp. 29-33. https://doi.org/10.1017/S0021859600049972

Experiments with urea on spring barley.

A - Papers appearing in refereed journals

Widdowson, F. V. and Penny, A. 1960. Experiments with urea on spring barley. Experimental husbandry. 5, pp. 22-26.

The value of calcium nitrate and urea for main-crop potatoes and kale

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A., Williams, R. J. B. and Cooke, G. W. 1960. The value of calcium nitrate and urea for main-crop potatoes and kale. The Journal of Agricultural Science. 55 (1), pp. 1-10. https://doi.org/10.1017/S0021859600021560

The value of calcium nitrate and urea for spring-sown cereals

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A., Williams, R. J. B. and Cooke, G. W. 1959. The value of calcium nitrate and urea for spring-sown cereals. The Journal of Agricultural Science. 52 (2), pp. 200-206. https://doi.org/10.1017/S0021859600036698

Comparisons between combine-drilling and broadcasting muriate of potash for spring barley

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A., Williams, R. J. B. and Cooke, G. W. 1959. Comparisons between combine-drilling and broadcasting muriate of potash for spring barley. The Journal of Agricultural Science. 53 (1), pp. 10-16. https://doi.org/10.1017/S0021859600030860

Report on 1956 experiments on winter and spring sown cereals comparing methods of application of nitrogen and potassium fertilizers and forms of nitrogen fertilizers

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Cooke, G. W. 1957. Report on 1956 experiments on winter and spring sown cereals comparing methods of application of nitrogen and potassium fertilizers and forms of nitrogen fertilizers.

Report on 1956 experiments comparing placing and broadcasting of nitrogen, phosphorus and potassium for potatoes, peas, beans, kale and maize

A - Papers appearing in refereed journals

Widdowson, F. V., Penny, A. and Cooke, G. W. 1956. Report on 1956 experiments comparing placing and broadcasting of nitrogen, phosphorus and potassium for potatoes, peas, beans, kale and maize.

Comparisons of ammonium sulphate, calcium nitrate, and urea for potatoes and kale

A - Papers appearing in refereed journals

Cooke, G. W., Penny, A. and Widdowson, F. V. 1956. Comparisons of ammonium sulphate, calcium nitrate, and urea for potatoes and kale. ARC Conference on Fertilisers.