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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
- G. N. Thorne, P. J. Welbank, F. V. Widdowson, A. Penny, A. D. Todd, A. H. Weir
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- Journal:
- The Journal of Agricultural Science / Volume 110 / Issue 1 / February 1988
- Published online by Cambridge University Press:
- 27 March 2009, pp. 119-140
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Winter wheat grown following potatoes on a sandy loam at Woburn in 1978–9, 1980–1 and 1981–2 was compared with that on a clay loam at Rothamsted in 1978–9 and 1980–1, and on a silty clay (alluvium) at Woburn in 1981–2. The cultivar was Hustler in the harvest years 1979 and 1981 and Avalon in 1982. On each soil in each year multifactorial experiments tested effects of combinations of six factors, each at two levels.
The best 4-plot mean grain yield ranged from 89 to 11·1 t/ha during the 3 years; it was smaller on the sandy soil than on the clay soil in 1979, but larger on sand than on the clay in 1981 and 1982. Until anthesis the number of shoots, dry weight and N content of the wheat giving these best yields were less on sand than on clay. Unlike grain weight, straw weight was always less on sand.
Sowing in mid-September instead of mid-October increased grain yield on clay in each year (by 0·4·0·7 t/ha) and increased yield on sand only in 1981 (by 1·6 t/ha). Early sowing always increased dry weight, leaf area, number of shoots and N uptake until May. The benefits were always greater on clay than on sand immediately before N fertilizer was applied in the spring and usually lessened later on both soils.
Aldicarb as an autumn pesticide increased grain yield of early-sown wheat on both soils in 1981 by lessening infection with barley yellow dwarf virus. Aldicarb increased yield on clay in 1982; it also decreased the number of plant parasitic nematodes.
Wheat on sand was more responsive to nitrogen in division, timing and amount than was wheat on clay. In 1979 yield of wheat on sand was increased by dividing spring N between March, April and May, instead of giving it all in April, and in 1982 by giving winter N early in February. In 1981 division and timing on sand interacted with sowing date. Yield of early-sown wheat given N late, i.e. in March, April and May, exceeded that given N early, i.e. in February, March and May, by 1·4 t/ha; single dressings given all in March or all in April also yielded less than the late divided dressing. Yield of later-sown wheat given all the N in April was at least 1·2 t/ha less than with all N given in March or with divided N. In all years treatments that increased yield usually also increased N uptake. Grain yield on clay was never affected by division or timing of spring N or by application of winter N. This was despite the fact that all treatments that involved a delay in the application of N depressed growth and N uptake in spring on both sand and clay. The mean advantage in N uptake following early application of spring N eventually reversed on both soils, so that uptake at maturity was greater from late than from early application. Increasing the amount of N given in spring from the estimated requirement for 9 t/ha grain yield to that for 12 t/ha increased yield in 1982, especially on sand. The larger amount of N always increased the number of ears but often decreased the number of grains per ear and the size of individual grains.
Irrigation increased grain yield only on the sandy soil, by 1·1 t/ha in 1979 and by 07 t/ha in 1981 and 1982. The component responsible was dry weight per grain in 1979 and 1982, when soil moisture deficits reaching maximum values of 136 and 110 mm respectively in the 2 years developed after anthesis; the component responsible was number of ears/m2 in 1982 when the maximum deficit of 76 mm occurred earlier, in late May.
Variation between years in growth and nutrient uptake after anthesis of winter wheat on Broadbalk field at Rothamsted, 1969–84
- G. N. Thorne, R. J. Darby, W. Day, P. W. Lane, P. J. Welbank, F. V. Widdowson
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- Journal:
- The Journal of Agricultural Science / Volume 110 / Issue 3 / June 1988
- Published online by Cambridge University Press:
- 27 March 2009, pp. 543-559
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Dry weight, nutrient content and other properties of winter wheat were measured from anthesis to maturity between 1969 and 1984. From 1969 to 1978 the cultivar Capelle- Desprez was grown either as a first wheat, in the rotation potatoes, beans, wheat, or as a second wheat, in the rotation fallow, wheat, wheat. From 1979 to 1984 the cv. Flanders was grown in the rotation fallow, potatoes, wheat and in this period the wheat was given fungicide sprays. Grain yield of Cappelle-Desprez grown as a first wheat was greater with 96 than with 144 kg N/ha in spring. First wheats yielded much more than second wheats with 96, but not with 144 kg N/ha. Second wheats had more eyespot and take-all, but less mildew, than first wheats. Mildew was more severe with the larger amount of N. Grain yield of Flanders as a first wheat was greater than that of Cappelle-Desprez. Yield of Flanders was greater with 144 than with 96 kg N/ha and it was greater still on plots given 96 kg Nha plus 35 t/ha farmyard manure. Other properties in addition to grain yield were changed by cultivar, rotation and manuring.
Examination of the variation between years showed relationships among properties and between some of them and grain yield. Many of the relationships were independent of cultivar or husbandry. Relationships between weather factors and some properties, but not grain yield, were detected. Grain yield of first wheats was closely related to number of grains/m2, but the relative importance of number of ears/m2 and number of grains per ear varied from year to year. Yield was positively related to dry weight per grain in Flanders, but negatively in Cappelle-Desprez. The weight of straw was usually less than that of the total above-ground crop at anthesis, but varied between years in a similar manner. The amount of N in grain plus straw was generally well related to the amount of N in the wheat at anthesis, although the changes in N content after anthesis ranged from a loss of 9 kg/ha to a gain of 51 kg/ha. The uptake of N, P and K was more closely related to dry weight than to nutrient concentration.
Variation between years in the proportion in the ear of 14C supplied to the flag leaf was similar to that of 14C supplied to the next lower leaf, but was different for 14C supplied before and after anthesis, and did not relate to other properties.
Date of anthesis ranged from 7 June to 5 July. A model incorporating responses to photoperiod, vernalization and temperature accounted for 78% of the variance in date of anthesis. The duration of the period from anthesis to leaf senescence ranged from 33 to 60 days and was linearly related to mean temperature above a base of 7·5 °C. Dry weight per grain was negatively correlated with mean temperature between anthesis and leaf senescence; a relationship including an adjustment for number of grains/m2 fitted both cultivars.
The amount of N in grain plus straw and percentage of N in grain dry matter were decreased by increased rainfall during the 3-week period following the application of N fertilizer in spring. An additional 10 mm of rain decreased N uptake by 2–8 kg/ha and N percentage by 0·055. N uptake in grain plus straw decreased with progressively later sowing. Grain N% was positively correlated with temperature and with radiation during parts of the period of grain growth, but only 10% of the variance was accounted for by the combined effects.