Cereal Crops Economics, Statistics and Uses the period 1960-1989 are shown diagrammatically Cereals are the fruits of cultivated grasses members of the monocotyledonous family Production barley, oats, rye, rice, maize, sorghum and t6 s, Gramineae. The principal cereal crops are wheat The world production of wheat millets rye, rice (paddy), maize, sorghum and millet Cereals have been important crops for thou- was estimated at 1233 million tonnes(Mt) in sands of years; indeed, the successful production, 1969-1971, rising to 1652 Mt in 1981, and to storage and use of cereals has contributed in no 1784 Mt in 1987-1989.* small measure to the development of modern The total world production of the eight major civilization cereals in 1987-1989 would have been sufficient to provide approximately 350 kg of cereal grain World crops per head per annum, or about 960 g per head per day, if the entire world Area estimated for 1981, which was 370 kg of cereal The area occupied by the eight cereals averaged grain per head per annum, indicating that the 665 million ha over the 3-year period of increase in total world production is not quite 1969-1971, and increased to 719 M ha on average keeping pace with the increase in world population in the period 1979-1981. There was a slight fall, The average human consumption of cereals is to an average of 691 M ha, in the period only about one half of these figures, as a variable 1987-1989. Between 1965 and 1989 the area proportion is used for other purposes, mainly under wheat, barley, maize, rice and sorghum animal feed, industrial processing, and seed, and has shown a small increase, whereas the area there is considerable wastage. Thus, in 1984-1986, under oats, rye and millet has decreased slightly of a world total domestic supply of 1677 Mt of all The total area occupied by cereals in 1987-1989 cereals, 49% was used for human food, giving an was 5.3% of the entire land surface of the world. average consumption of 171 kg per head per e annual world area and production and the annum, 37% was used for animal feed, 10% for average world yield of the individual cereals over processing and other uses, and 4% for seed op data for earlier years have been derived from Grain Crops and grain B by permission of the Commonwealth tariat;those for later form F.A.o. Production Year Books and F.A. 0 Year books or f.a.o. food balance and from h-GCa Cereal statistics
I Cereal Crops: Economics, Statistics and Uses Cereals Cereals are the fruits of cultivated grasses, members of the monocotyledonous family Gramineae. The principal cereal crops are wheat, barley, oats, rye, rice, maize, sorghum and the millets. Cereals have been important crops for thousands of years; indeed, the successful production, storage and use of cereals has contributed in no small measure to the development of modern civilization. the period 1960-1989 are shown diagrammatically in Fig. 1.1. Production The world production of wheat, barley, oats, rye, rice (paddy), maize, sorghum and millet was estimated at 1233 million tonnes (Mt) in 1969-1971, rising to 1652 Mt in 1981, and to 1784 Mt in 1987-1989.* The total world production of the eight major cereals in 1987-1989 would have been sufficient to provide approximately 350 kg of cereal grain per head per annum, or about 960 g per head per day, if shared equally among the entire world population. This is a slight reduction on the figure estimated for 1981, which was 370 kg of cereal Area The area occupied by the eight cereals averaged grain per head per annum, indicating that the 665 million ha over the 3-year period of increase in total world production is not quite 1969-1971, and increased to 719 M ha on average keeping pace with the increase in world population. in the period 1979-1981. There was a slight fall, The average human consumption of cereals is to an average of 691 M ha, in the period only about one half of these figures, as a variable 1987-1989. Between 1965 and 1989 the area proportion is used for other purposes, mainly under wheat, barley, maize, rice and sorghum animal feed, industrial processing, and seed, and has shown a small increase, whereas the area there is considerable wastage. Thus, in 1984-1986, under oats, rye and millet has decreased slightly. of a world total domestic supply of 1677 Mt of all The total area occupied by cereals in 1987-1989 cereals, 49% was used for human food, giving an was 5.3% of the entire land surface of the world. average consumption of 171 kg per head per The annual world area and production and the annum, 37% was used for animal feed, 10% for average world yield of the individual cereals over processing and other uses, and 4% for seed. World crops * Crop data for earlier years have been derived from Grain Crops and Grain Bulletin by permission of the Commonwealth Secretariat; those for later years form F.A.O. Production Year Books and F.A.O. Trade Year Books or F.A.O. Food Balance Sheets, and from H-GCA Cereal Statistics. 1
TECHNOLOGY OF CEREALS Rice, poddy 9+8三 Yield Millet Harvest year Clio ommon teath sel tarna a n Ddu vix n uroS tAld yield, f prin cereals since 1960.(S
250 200 yl 2 01 C c { 150- G? 5 loo- 5 2 - - c Area Wheat ! /-e-- Rice Maize paddy 30 25 m E 2 Y \ .c s o I5 z c; 5 Maize Rice, paddy - Yield - 0 -’ /-e-’ -Wheat Barley // 20-i:::s 35-/ Sorghum - 4 lo-x.fl. - fi Ml11et 0‘ I I I I I I
CEREAL CROPS: ECONOMICS, STATISTICS AND USES yield t/ha), corn meal (2.04 t/ha) and white wheat four The proportion of the total harvested the eight cereals is similar content in k]/g(15.7 for milled rice, 16.61 area 1.72 t/ha by the respective figures for energy contributed by each of for corn to,or greater than, the proportion of the total meal, 16. I for white wheat flour). As regards food production, except for maize and rice(see Table protein yield, rice, producing 0.18 t/ha of protein 1. 1). This is because the yields of wheat, barley, (in milled rice), is second only to wheat, produc oats, rye and sorghum do not vary greatly among ng 0 19 t/ha(in white flour), followed by oats, abour, s(and that for millet is very low), producing 0.15 t/ha(in oatmeal) whereas times the average yield of all the other reals (apart from millet. Taking all the cereals Wheat together, the average yield for the whole world progressively from 18. 1 q/ Cultivation 1969-1971to22.5q/hain1981, and to258 g/ha in 1987-1989. Between 1969 and 1989, the Wheat is grown throughe world, from yield of maize increased by 11. 8 q/ha(from 24.7 e borders of the arctic to near the equator, to 36.5 q/ha), largely through the use of hybrid although the crop is most successful between the maize(cf. p. 99), and that of rice(padd latitudes of30°and60° North and27°and40° increased by 12. 1 q/ha(from 22.6 q/ha in 1969 South. In altitude, it ranges from sea level to 34.7 q/ha in 1989), whereas that of all other 3050 m in Kenya and 4572 m in Tibet. It adaptable to a range of environmental conditions cereals together increased by only 3.9 q/ha on from xerophytic to littoral distribution of the world cereals area and produc Wheat grows best on heavy loam and clay tion and the world average yields for each cereal although it makes a satisfactory crop on light over the period 1987-1989 are shown in Table 1.1 land. The crop repays heavy nitrogenous manuring. TABLE Wheat flourishes in subtropical, warm tempe World Cereal Area, Production and yield for the Period rate and cool temperate climat 1987-1989★ rainfall of 229-762 mm, falling more in spring of total temperature should be 13C (56F)or more. production (q/hat) The seed is sown in late autumn( winter wheat) Wheat 32 23.3 or in spring(spring wheat). Winter wheat can be Barley rown in places, e.g. northwestern Europe, where excessive freezing of the soil does not Rice(paddy) 33. 8 occur. The grain germinates in the autumn and Maize grows slowly until the spring Frost would affect Millet 14.0 the young plants adversely, but a covering of snow protects them and promotes tillering. In ★ ed from F. A.O. Production Year Book(1990). countries such as the Canadian prairies and the t N.B. 1 qha 0.79 cwt/ac. steppes of russia that experience winters too severe for winter sowing, wheat is sown as early s sources of carbohydrate related to land use, as possible in the spring, so that the crop may be rice, producing 38. 1 x 106 kJ/ha, ranks first harvested before the first frosts of autumn. The among cereal grains, followed by maize with 33. 9 area of production of spring wheat is being x 10 k]/ha and wheat with 27.7 x 10 k]/ha. extended progressively northwards in the northern These figures are obtained by multiplying the hemisphere by the use of new varieties bred for 1989 average world yield of milled rice(2.43 their quick -ripening characteristics
CEREAL CROPS: ECONOMICS, STATISTICS AND USES 3 t/ha), corn meal (2.04 t/ha) and white wheat flour (1.72 t/ha) by the respective figures for energy content in kJ/g (15.7 for milled rice, 16.6 for corn meal, 16.1 for white wheat flour). As regards food protein yield, rice, producing 0.18 t/ha of protein (in milled rice), is second only to wheat, producing 0.19 t/ha (in white flour), followed by oats, producing 0.15 t/ha (in oatmeal). Yield The proportion of the total harvested area contributed by each of the eight cereals is similar to, or greater than, the proportion of the total production, except for maize and rice (see Table 1.1). This is because the yields of wheat, barley, oats, rye and sorghum do not vary greatly among themselves (and that for millet is very low), whereas the yields of maize and paddy rice are about 1.7 times the average yield of all the other cereals (apart from millet). Taking all the cereals together, the average yield for the whole world increased progressively from 18.1 q/ha in Cultivation 1969-1971 to 22.5 q/ha in 1981, and to 25.8 yield of maize increased by 11.8 q/ha (from 24.7 maize (cf. p. 99), and that of rice (paddy) increased by 12.1 q/ha (from 22.6 q/ha in 1969 to 34'7 q/ha in 1989)y whereas that Of a11 Other cereals together increased by only 3.9 q/ha on average (from 13.8 to 17.7 q/ha). The percentage distribution of the world cereals area and production and the world average yields for each cereal over the period 1987-1989 are shown in Table 1.1 TABLE 1.1 World Cereal Area, Production and Yield for the Period 1987-1989* Wheat Wheat is grown throughc ! world, from although the crop is most successful between the South. In altitude, it ranges from sea level to 3050 m in Kenya and 4572 m in Tibet. It is adaptable to a range of environmental conditions from xerophytic to littoral. Wheat grows best on heavy loam and clay, although it makes a satisfactory crop on lighter land. The crop repays heavy nitrogenous manuring. Wheat flourishes in subtropical, warm temperate and c001 temperate c1imates* An annua1 rainfall of 229-762 mm, falling more in spring than in summer, suits it best. The mean summer Cereal area production (q/hat) The seed is sown in late autumn (winter wheat) 29 Wheat or in spring (spring wheat). Winter wheat can be 32 Barley 11 10 22.6 grown in places, e.g. northwestern Europe, Oats 3 2 17.8 where excessive freezing of the soil does not occur. The grain germinates in the autumn and Rye 2 2 Rice (paddy) 21 27 Maize 19 25 34.5 grows slowly until the spring. Frost would affect Sorghum 7 3 14.0 the young plants adversely, but a covering of snow protects them and promotes tillering. In Millet 5 2 countries such as the Canadian prairies and the steppes of Russia that experience winters too severe for winter sowing, wheat is sown as early as possible in the spring, so that the crop may be harvested before the first frosts of autumn. The area of production of spring wheat is being extended progressively northwards in the northern hemisphere by the use of new varieties bred for their quick-ripening characteristics. dha in 1987-1989* Between 1969 and 1989Y the the borders of the arctic to near the equator, to 36*5 q/ha)Y largely through the use Of hybrid latitudes of 300 and 600 North and 270 and 400 Percentage Percentage Average of total of total yield temperature should be 13°C (56°F) or more. 23.3 :!:: 7.8 * Data derived from F.A.O. Production Year Book (1990). t N.B. 1 q/ha = 0.79 cwt/ac. As sources of carbohydrate related to land use, rice, producing 38.1 x lo6 kJ/ha, ranks first among cereal grains, followed by maize with 33.9 x lo6 kJ/ha and wheat with 27.7 x lo6 kJ/ha. These figures are obtained by multiplying the 1989 average world yield of milled rice (2.43
TECHNOLOGY OF CEREALS Imes of sowing and harvesting of the wheat in Ireland an average yield of /y/ q/ha was ally dependent upon local climatic conditions; of 42-75 g/ha were general in other northwestern wheat is being harvested in some country in every European countries in the same year. However, month of the year. However, the storage facilities in more primitive agricultural communities in most wheat-growing countries are adequate to and in countries with less favourable climatic permit the best part of a years harvest being conditions, yields are still around 12 q/ha. The stored; thus, the British miller can buy wheat improvements in wheat yields since 1956/61 are from any exporting country at almost any time particularly striking in Europe(both Western and of the year. The times of harvest for the principal Eastern), China, and India/Pakistan(see Fig. 1. 2) wheat-growing countries are shown in Table 1. 2 Wheat yield also depends upon the type of heat sown: winter wheat(autumn-sown), with TABLE 1.2 a longer growing period than spring wheat Times of Wheat Harvest normally produces a higher yield than spring Country Harvest time 79). The yield of durum India wheat(cf. p. 79), which is grown in drier areas February is lower than that of bread wheat June-Jul The present yield of wheat in the U. K.(71 franc U.S.A q/ha in 1991)is over three times the pre-war figure May-September of 23 g/ha. In the U.S.A. yields have increased from 9 q/ha pre-war to 25 qha in 1987. The capacity for cereal production continues numa October-January to increase due to the use of higher-yielding November-Ja nary varieties, and by changes in husbandry. The ultimate aim of the grower is to obtain the Area, production, yield maximum yield of millable' wheat, just as it is of the plant breeder, even when he directs Between 1965 and 1989 the world wheat area his attention towards the breeding of varieties showed a small increase(215-227 M ha)while which are resistant to drought, frost and diseases wheat production doubled, from 261 to 537 Mt(Percival, 1921) per annum, reflecting the increase in world aver- Both the yield and the quality of the wheat age yield over the period, from 12 to 23.6 crop are affected by conditions of soil, climate g/ha. This increase has been due to the use of and farm management. The yield of flour obtain- more highly yielding varieties, the greater use of able from the wheat during milling is dependent fertilizers, and improved husbandry upon the degree of maturation- the extent to The area under wheat, the production, and the which individual grains are filled out with endo average yield in the principal wheat-producing sperm. Premature ripening, sometimes brought ountries and regions of the world, for four on by high temperatures prevailing in the later selected periods(1956/61, 1969/71, 1979/81 and part of the season, produces shrivelled grain 1986/88)are shown diagrammatically in Fig. 1. 2. which is of high protein content because relatively In the period 1986/88 the former Soviet Union more protein than starch is laid down in the and China each produced 18% of the world crop, endosperm during the early stages of ripening Western Europe 15. 3%, India/Pakistan 12%, the whereas the reverse holds during the later stages U.S.A. 11.2%, Eastern Europe 9. 1%, Canada 5% The effect of treatment with nitrogenous ferti urkey livers depends on the time of application and the The yield varies considerably among producing availability of nitrogen in the soil. Nitrogen taken countries and regions, and is related to the water up by the wheat plant early in growth results in supply and the intensity of cultivation. In 1990 increased tillering( see Ch 2)which can result in
4 TECHNOLOGY OF CEREALS Times of sowing and harvesting of the wheat in Ireland an average yield of 79.7 q/ha was crop in the various growing countries are natur- obtained, and 76.5 q/ha in the Netherlands; yields ally dependent upon local climatic conditions; of 42-75 q/ha were general in other northwestern wheat is being harvested in some country in every European countries in the same year. However, month of the year. However, the storage facilities in more primitive agricultural communities, in most wheat-growing countries are adequate to and in countries with less favourable climatic permit the best part of a year’s harvest being conditions, yields are still around 12 q/ha. The stored; thus, the British miller can buy wheat improvements in wheat yields since 1956/61 are from any exporting country at almost any time particularly striking in Europe (both Western and of the year. The times of harvest for the principal Eastern), China, and IndialPakistan (see Fig. 1.2). wheat-growing countries are shown in Table 1.2. Wheat yield also depends upon the type of wheat sown: winter wheat (autumn-sown), with TABLE 1.2 a longer growing period than spring wheat, normally produces a higher yield than springCountry sown wheat (cf. p. 79). The yield of durum wheat (cf. p. 79), which is grown in drier areas, is lower than that of bread wheat. India February The present yield of wheat in the U.K. (71 China May Italy June-July France June- July qiha in 1991) is over three times the pre-war figure of 23 q/ha. In the U.S.A., yields have increased U.S.A. May-September Former Soviet Union July-September Canada July-September from 9 q/ha pre-war to 25 qlha in 1987. England August-September The capacity for cereal production continues to increase due to the use of higher-yielding Australia October-January Argentina November- January varieties, and by changes in husbandry. The ultimate aim of the grower is to obtain the maximum yield of ‘millable’ wheat, just as it is of the plant breeder, even when he directs Area, production, yield Between 1965 and 1989 the world wheat area his attention towards the breeding of varieties showed a small increase (215-227 M ha) while which are resistant to drought, frost and diseases wheat production doubled, from 261 to 537 Mt (Percival, 1921). per annum, reflecting the increase in world aver- Both the yield and the quality of the wheat age yield over the period, from 12 to 23.6 crop are affected by conditions of soil, climate q/ha. This increase has been due to the use of and farm management. The yield of flour obtainmore highly yielding varieties, the greater use of able from the wheat during milling is dependent fertilizers, and improved husbandry. upon the degree of maturation - the extent to The area under wheat, the production, and the which individual grains are filled out with endoaverage yield in the principal wheat-producing sperm. Premature ripening, sometimes brought countries and regions of the world, for four on by high temperatures prevailing in the later selected periods (1956/61, 1969/71, 1979/81 and part of the season, produces shrivelled grain, 1986/88) are shown diagrammatically in Fig. 1.2. which is of high protein content because relatively In the period 1986188 the former Soviet Union more protein than starch is laid down in the and China each produced 18% of the world crop, endosperm during the early stages of ripening, Western Europe 15.3%, IndiaPakistan 12%, the whereas the reverse holds during the later stages. U.S.A. 11.2%, Eastern Europe 9.1%, Canada 5% The effect of treatment with nitrogenous fertiand Turkey 4%. lizers depends on the time of application and the The yield varies considerably among producing availability of nitrogen in the soil. Nitrogen taken countries and regions, and is related to the water up by the wheat plant early in growth results in supply and the intensity of cultivation. In 1990 increased tillering (see Ch. 2) which can result in Times of Wheat Harvest Harvest time
CEREAL CROPS: ECONOMICS, STATISTICS AND USES W Europe china Indio/P Wheat crea million ha Argentino Africo nn示 MiLlion hectare china Canada Argentina Africa w Europa hing Wheat yield q/ E Europe Austro Lig 969/71 1979/8 Argentino Africa Quintals/hectare F971 29. adud ti9 a-n988. d of rces gra th crops commonw ealth siecetaiat p.. t world in1956-1961,1969
CEREAL CROPS: ECONOMICS, STATISTICS AND USES 5 USSR W Europe USA China IndidPok E Europe Canada Turkey Australia Argentina Africa Wheat oreo million ha USSR W Europe USA China Indio/Pak E Europe Canada Turkey Australia Argentina Africa Wheat production million t Million tonnes USSR W Europe USA China lndia/Pak E Europe Canada Turkey 0 1956161 0 1969/71 m 1979/81 = 1986/88 Wheat yield q/ha Austra Lia Argentina Africa Quintals/ hectare FIG 1.2 Area, production and yield of wheat in the main producing countries and regions of the world in 1956-1961, 1969- 1971, 1979-1981 and 19861988. (Sources: Grain Crops (Commonwealth Secretariat); F.A.O.)
TECHNOLOGY OF CEREALS increased grain yield. If prolonged tillering occurs, countries, 28% by the U.S.A., 18% by Canada he last ears formed may not ripen but produce 12% by Australia, 6% by Argentina, 1% by the small immature grains. Nitrogen taken up after former Soviet Union, and 1% by saudi arabia heading is laid down as additional protein in the About nine-tenths of the wheat exports are in seed, with a consequent improvement in nutritive the form of unmilled grain, the remainder as value and often baking quality also Possible ways four. The major exporters of wheat four in 1990 of making nitrogen available at a late stage of were france(23.5% of the total), Italy (17.8%), fertilizers or the late application of foliar sprays, and germany FR(7. 3%) American four goes to e.g. urea, possibly by means of aircraft a large number of countries, but mostly to Egypt (55%of total U.S. flour exports in 1989/90)and Green Revolution the Yemen. Much of the flour exported from Canada goes to Morocco and Cuba. france has This is an expression used to describe the rapid big markets for flour in her former Africa spread of high-yielding varieties of wheat and rice territories in many developing countries, particularly in European imports accounted for 16% of the Asia. The threat of a massive famine in these world movement of wheat in 1990. Other large countries has been averted at least in the short importers of wheat in 1990 were the former run, through the success of the Green Revolution. Soviet Union(15%), China(13%), Japan(6%) Characteristics of the new varieties of wheat Egypt (6%), India/ Bangladesh/Pakistan (4%) and rice, and of their use, are: higher, often Iran(4%), Algeria(3%)and Korea% doubled yield of grain per unit of area, combined Wheat flour is imported principally by Egypt with a similar protein content(thus giving the Libya, Syria, Cuba, Hong Kong, Cameroon and possibility of a doubled yield of protein; a larger Yemen These countries absorbed about 53% of return of grain per unit of fertilizer applied and the total trade in wheat four in 1989/90. Imports per man-hour of labour expended; higher yield of flour decrease sharply when a domestic four of protein per unit of irrigation water; early milling industry is established: this happened maturation; less sensitivity to day length, giving about 1960 in the Philippines, 1977 in Egypt greater flexibility in planting time and the 1980 in Sri Lanka ssibility of two or even three crops per year. The effect of the green revolution in India, Utilization for example, has been to increase the amount of wheat available to the total population from 23.4 Data for the domestic utilization of wheat kg per person in 1967 to 52.5 kg per person in certain countries are shown in Table 1.3. 19841986 The most rapid exploitation of the greer Wheat quality Revolution occurs in areas where the land is most 'Quality in the general sense means 'suitability productive, and where a high proportion of the for some particular purpose'; as applied to wheat land is already irrigated Other regions are less the criteria of quality are well suited to benefit from the green revolution yield of end product(wheat, for the grower; ur, for the miller; bread or baked goods, for Crop movements the baker, etc); Over the period 1977/78 to 1990/91, 16-22% of (average 19%)of the entire world wheat crop was o nature of the end product exported from the producing country to other ability, appearance, chemical compos untries.Of the total exports of wheat, as grain, in 1990, 33% was provided by Europ
6 TECHNOLOGY OF CEREALS increased grain yield. If prolonged tillering occurs, the last ears formed may not ripen but produce small immature grains. Nitrogen taken up after heading is laid down as additional protein in the seed, with a consequent improvement in nutritive value and often baking quality also. Possible ways of making nitrogen available at a late stage of growth are the early application of slow-acting fertilizers or the late application of foliar sprays, e.g. urea, possibly by means of aircraft. Green Revolution This is an expression used to describe the rapid spread of high-yielding varieties of wheat and rice in many developing countries, particularly in Asia. The threat of a massive famine in these countries has been averted, at least in the short run, through the success of the Green Revolution. and rice, and of their use, are: higher, often doubled, yield of grain per unit of area, combined with a similar protein content (thus giving the possibility of a doubled yield of protein); a larger return of grain per unit of fertilizer applied and per man-hour of labour expended; higher yield of protein per unit of irrigation water; early maturation; less sensitivity to day length, giving greater flexibility in planting time and the 1980 in Sri Lanka. possibility of two or even three crops per year. The effect of the Green Revolution in India, for example, has been to increase the amount of wheat available to the total population from 23.4 kg per person in 1967 to 52.5 kg per person in 1984-1 986. The most rapid exploitation of the Green Revolution occurs in areas where the land is most productive, and where a high proportion of the land is already irrigated. Other regions are less well suited to benefit from the Green Revolution. Crop movements the baker, etc); ability, appearance, chemical composition. (average 19%) of the entire world wheat crop was exported from the producing country to other countries. Of the total exports of wheat, as These criteria of quality are dependent upon grain, in 1990, 33% was provided by European the variety of wheat grown and upon environment countries, 28% by the U.S.A., 18% by Canada, 12% by Australia, 6% by Argentina, 1% by the former Soviet Union, and 1% by Saudi Arabia. About nine-tenths of the wheat exports are in the form of unmilled grain, the remainder as flour. The major exporters of wheat flour in 1990 were France (23.5% of the total), Italy (17.8%), U.S.A. (12.9%), BelgiudLuxembourg (8.6%) and Germany FR (7.3%). American flour goes to a large number of countries, but mostly to Egypt (55% of total U.S. flour exports in 1989/90) and the Yemen. Much of the flour exported from Canada goes to Morocco and Cuba. France has big markets for flour in her former African territories. European imports accounted for 16% of the world movement of wheat in 1990. Other large importers of wheat in 1990 were the former Soviet Union (15%), China (13%), Japan (6%), Characteristics of the new varieties of wheat Egypt (6%), India/Bangladesh/Pakistan (‘+yo), Iran (4%), Algeria (3%) and Korea (3%). Wheat flour is imported principally by Egypt, Libya, Syria, Cuba, Hong Kong, Cameroon and Yemen. These countries absorbed about 53% of the total trade in wheat flour in 1989/90. Imports of flour decrease sharply when a domestic flourmilling industry is established: this happened about 1960 in the Philippines, 1977 in Egypt, Utilization certain Gountries are shown in Table 1.3. Wheat quality ‘Quality’ in the general sense means ‘suitability for some particular purpose’; as applied to wheat, the criteria of quality are: ~ yield of end product (wheat, for the grower; flour, for the miller; bread or baked goods, for Data for the domestic utilization of wheat in 0 ease of processing; Over the period 1977/78 to 1990/91, 16-22% nature of the end product: uniforfity, palat-
CEREAL CROPS: ECONOMICS, STATISTICS AND USES TABLE 1.3 Domestic Consumption of Common Wheat in Certain Countries Total Percentage of total consumption domestic Y 198486 9899 Bel /Lux 61 2.0 nmark 11,671 43.8 Germany, FR 43.0 2.0 12.6 25,2 81.9 14.3 24.9 11,367 43,6 48.2 1984/86 New Zealand 3.6 Former Soviet union Sources: (1)EC Commission Documents, via HGCA Cereal Statistics(1991a);(2)FA O. Food Balance Sheets, 1990 climate, soil and manurial or fertilizer treat- for example, bread, biscuits or cakes. He wants his ment. Within the limits of environment, quality four to yield the maximum quantity of goods which is influenced by characteristics that can be varied meet rigid specifications, and therefore requires ray y breeding, and is further modified during materials of suitable and constant quality. es rav harvesting, farm drying, transportation and The consumer requires palatability and good storage ppearance in the goods he purchases; they should have high nutritive value and be reasonably priced Wheat passes through many hands between the Field damage to wheat field and the table all those who handle it are The yield of wheat may be reduced, and its interested in the quality of the cereal, but in quality impaired, by the attack of various fungal different ways and animal pests in the field The grower requires good cropping and high yields Heis not concerned with quality(provided Rusts the wheat is 'fit for milling or fit for feeding') unless he sells the grain under a grading system These are fungal diseases caused by species of associated with price differentials(cf. p. 88) the genus Puccinia. Yellow or Stripe Rust (P The miller requires wheat of good milling striiformis) and Brown or Leaf Rust(P recondita quality-fit for storage, and capable of yielding tritici) sometimes occurring in the west of Britain the maximum amount of flour suitable for a are particularly troublesome in the U.S.a particular purpose Canada and Argentina, and generally in countries The baker requires four suitable for making, with a hot climate
CEREAL CROPS: ECONOMICS, STATISTICS AND USES 7 TABLE 1.3 Domestic Consumption of Common Wheat in Certain Countries Total Percentage of total consumption usage Human Industrial Source Country Year (thousand t) food usage* Feed Seed of data World 1984186 507,691 66.5 6.7 20.2 6.6 2 EC 1989/90 58,080 53.8 4.6 36.6 5.0 1 Bel.1Lux. 1710 61.6 19.3 17.1 2.0 1 Denmark 1946 17.0 - 78.1 4.9 1 France 11,671 43.8 5.0 45.0 6.2 1 Germany, FR 10,118 41.8 5.9 49.3 3.0 1 Greece 1790 82.1 - 6.7 11.2 1 Ireland 710 42.3 12.7 43.0 2.0 1 Italy 10,310 80.0 0.6 12.6 6.8 1 Netherlands 1995 53.0 20.5 25.2 1.3 1 Portugal 1050 81.9 - 14.3 3.8 1 Spain 5413 67.1 1.1 24.9 6.9 1 U.K. 11,367 43.6 5.1 48.2 3.1 1 Australia 1984/86 3587 43.4 10.3 22.2 24.1 2 Canada 5618 37.0 - 41.0 22.0 2 Japan 6140 80.7 9.5 9.6 0.2 2 New Zealand 360 78.3 0.6 17.5 3.6 2 Turkey 19,020 50.6 24.4 16.3 8.7 2 U.S.A. 29,828 59.7 - 32.0 8.3 2 Former Soviet Union 96,204 40.1 10.7 39.2 10.0 2 domestic * Including waste. Sources: (1) EC Commission Documents, via HGCA Cereal Statistics (1991a); (2) F.A.O. Food Balance Sheets, 1990. - climate, soil and manurial or fertilizer treat- for example, bread, biscuits or cakes. He wants his ment. Within the limits of environment, quality flour to yield the maximum quantity of goods which is influenced by characteristics that can be varied meet rigid specifications, and therefore requires raw by breeding, and is further modified during materials of suitable and constant quality. harvesting, farm drying, transportation and The consumer requires palatability and good storage. appearance in the goods he purchases; they should have high nutritive value and be reasonably priced. Quality requirements Field damage to wheat Wheat passes through many hands between the field and the table: all those who handle it are The yield of wheat may be reduced, and its interested in the quality of the cereal, but in quality impaired, by the attack of various fungal different ways. and animal pests in the field. The grower requires good cropping and high Rusts yields. He is not concerned with quality (provided the wheat is ‘fit for milling’ or ‘fit for feeding’) unless he sells the grain under a grading system These are fungal diseases caused by species of associated with price differentials (cf. p. 88). the genus Puccinia. Yellow or Stripe Rust (P. The miller requires wheat of good milling striifomzis) and Brown or Leaf Rust (P. recondita quality - fit for storage, and capable of yielding tritici) sometimes occurring in the west of Britain, the maximum amount of flour suitable for a are particularly troublesome in the U.S.A., particular purpose. Canada and Argentina, and generally in countries The baker requires flour suitable for making, with a hot climate
TECHNOLOGY OF CEREALS Rusts exist in many physiological races or permitted in the U. K ), copper carbonate, or forms, and from time to time new races arise to formaldehyde which hitherto resistant strains of cereals may be susceptible. Thatcher wheat(cf. p. 83) was Loose smut to be susceptible to race 15B in 1950. Selkirk is The fungus Ustilago nuda infects wheat plants a variety, bred for Canadian and U. S HRS areas. at flowering time. The disease is of little import which is resistant to stem rust isb ance to the miller, but is of concern to the grower Yellow Rust spread by air currents, and because infected plants fail to produce seed attacks cereal plants in favourable weather in May It can be controlled by seed treatments with for example, hot water, hot formaldehyde, or and June in central and western Europe. Bright benomyl with thiram(Benlate T)which induce range-yellow patches of spots appear on the leaves; the patches increase in size and in number the formation of quinones which are fungi-toxic and eventually prevent photosynthesis occurring in the leaves, and the plant starves. In a bad Mildew 90% of potential yield may be lost The fungus Erysiphe graminis infects the leaves of Immunity to rust, a varietal character, was bred cereal plants during warm humid weather in ApriI- into wheat by Biffen, using Rivet (riticum June, later producing greyish white patches of turgidum),Club(T compactum)or Hungarian Red spores, or 'mildew. The leaf surface becomes (T. aestivum)as the immune parent. The charac- obliterated by the fungus, reducing or preventing ter for immunity was recessive, appearing in one- photosynuormal grains Even a mild attack reduces quarter of the plants which, however, bred true thesis, and the plants become unable to for immunity in the Fi and subsequent genera- the yield. Systemic fungicides are useful against tions. Yellow Rust can be controlled by treatment mildew, which is best controlled, however, by with benodonil Calirus) and by a mixture of the growing of resistant varieties polyram and tridemorph( Calixin or by growing New varieties of cereals resistant to mildew in resistant Britain include Atem and Triumph(barleys), and Some improvement in resistance to rust in Fenman and Torfrida(wheats). However, most wheat has been achieved by incorporating part of the varieties of spring and winter wheat recom- of a chromosome derived from However, mended by the National Institute of Agricultural loughs made from flour of such substitution lines Botany in Britain are moderately resistant to (cf. p. 211)(Martin and Stewart, 1991) the Welsh Plant Breeding Institute, Aberystwyth Common bunt, stinking smut Take-a∥: Eye-spot This is a disease caused by the fungus Tilletia gaeumannomyces graminis and Pseudocercos- aries. The fungus enters the plant below ground, porella herpotrichoides, the fungi causing take-all and becomes systemic, and invades the ovaries eye-spot diseases, live in the soil, and may surviv the grain grows, it becomes swollen and full of on straw or stubble for a year or more. Plants black spores. Bunted grains are lighter in density affected by these diseases have empty or half-filled than normal grains and can be separated from the ears, and prematurely ripened or shrivelled grains latter at the cleaning stage by aspiration or Take -all may be controlled by suitable crop succes- flotation(see Ch 5). Bunt imparts an unpleasant sion. Eye-spot on winter wheat is controllable by aint of rotten fish( due to trimethylamine )to the treatment with benomyl, carbendazim, or a four and gives it an off-white colour. The disease formulation of thiophanate-methyl( Cercobin) is satisfactorily controlled by seed dressing Other fungal diseases of wheat are Leaf Spot with organo-mercury compounds(not currently caused by Mycosphaerella graminicola(= Septoria
8 TECHNOLOGY OF CEREALS Rusts exist in many physiological races or forms, and from time to time new races arise to which hitherto resistant strains of cereals may be susceptible. Thatcher wheat (cf. p. 83) was resistant to Stem Rust when released, but proved a variety, bred for Canadian and U.S. HRs areas, which is resistant to Stem Rust 15B. Yellow Rust is spread by air currents, and attacks cereal plants in favourable weather in May and June in central and western Europe. Bright leaves; the patches increase in size and in number and eventually prevent photosynthesis occurring in the leaves, and the plant starves. In a bad attack, 80-90% of potential yield may be lost. Immunity to rust, a varietal character, was bred permitted in the U.K.), copper carbonate, or formaldehyde. Loose smut at flowering time. The disease is of little importance to the miller, but is of concern to the grower because infected plants fail to produce seed. It can be controlled by seed treatmentS with, for examp1e, hot water, hot forma1dehyde, Or the formation of quinones which are fungi-toxic. Mildew The fungus Eysiphe graminis infects the leaves of cereal plants during warm humid weather in ~~~ilto be susceptible to race 15B in 1950. Selkirk is The fungus ustilago nuda infects wheat plants orange-yellow patches of spots appear on the benomyl with thiram (Benlate T) which induce into wheat by Biffen, using Rivet (Triticum tul'gidum), Club (T. compactum) or Hungarian Red June, later producing greyish white patches of spores, or 'mildew'. The leaf surface becomes (T. aestivum) as the immune parent. The character for immunity was recessive, appearing in oneobfiterated by the fungus, reducing or prevenhg photosw~esis, and the plants become unable to quarter of the plants which, however, bred true for immunity in the F1 and subsequent generadevelop normal grains. Even a mild attack reduces the yield. Systemic fungicides are useful against tions. Yellow Rust can be controlled by treatment with benodonil (Calirus) and by a mixture of resistant varieties. mildew, which is best controlled, however, by the growing of resistant varieties. Britain include Atem and Triumph (barleys), and polyram and tridemorph (CaliGn) or by growing New varieties of cereals resistant to mildew in Some improvement in resistance to rust in wheat has been achieved by incorporating part Fenman and Torfrida (wheats). However, most of the varieties of spring and winter wheat recomOf a chromosome derived from rye* However, mended by the National Institute of Agricultural doughs made from flour of such substitution lines B~~~~~ in ~~i~~i~ are moderately resistant to (cf. p. 211) (Martin and Stewart, 1991). the Welsh Plant Breeding Institute, Aberysnvyth. Common bunt, stinking smut Take-all; Eye-spot This is a disease caused by the fungus Tilletia Gaeumannomyces graminis and Pseudocercoscaries. The fungus enters the plant below ground, porella hqotrichoides, the fungi causing take-all and becomes systemic, and invades the ovaries. As eye-spot diseases, live in the soil, and may survive the grain grows, it becomes swollen and full of on straw or stubble for a year or more. Plants black spores. Bunted grains are lighter in density affected by these diseases have empty or half-filled than normal grains and can be separated from the ears, and prematurely ripened or shrivelled grains. latter at the cleaning stage by aspiration or Take-all may be controlled by suitable crop succesflotation (see Ch. 5). Bunt imparts an unpleasant sion. Eye-spot on winter wheat is controllable by taint of rotten fish (due to trimethylamine) to the treatment with benomyl, carbendazim, or a flour and gives it an off-white colour . The disease formulation of thiophanate-methyl (Cercobin). is satisfactorily controlled by seed dressing Other fungal diseases of wheat are Leaf Spot, with organo-mercury compounds (not currently caused by Mycosphaerella graminicola (= Septoria may display an UIKkk'able degree of stickiness mildew. Mildew-resistant oats have been bred at
CEREAL CROPS: ECONOMICS, STATISTICS AND USES tritici), Glume Blotch (Leptosphaeria Thrips Septoria nodorum)and Flag Smut tritici. A systemic fungicide recomm The larvae of tiny insects of the genus Haplothrips ind of other genera in the order Thysanoptera against Septoria on wheat is Tilt, a triazole. Flag al eloping inflorescence of wheat in western Smut can be controlled by seed treatment and by the dev wing), known as thrips, frequently attack the growing of resistant varieties Europe, but generally complete their develop. ment and leave the plants before the grain Ee/worm matures. In cold wet harvest years, however, the Wheat may be attacked by the eelworm adult insects occasionally fail to escape from the Anguina tritici, the grains becoming filled with plant, and become occluded in the crease(cf. p the worms, which are of microscopic dimensions. does not affect milling or baking quality of s 40: see Fig. 1.3. Attack by thrips apparentl Infected grains are known as"ear cockle(not to wheat but insects remaining in the crease are be confused with'corn cockle, the seeds of the fragmented during milling and contribute towards weed Agrostemma githago) the insect fragment count of the milled flour Kent,1969) Wheat bug Bugs of the species Aelia rostrata and eurygaster integriceps attack the wheat plants and puncture Rustic Shoulder Knot moth e immature grains, introducing with their saliva The larvae of the Rustic Shoulder Knot moth a proteolytic enzyme which modifies the protein, (Apamea sordens)feed on the developing wheat preventing the formation of a strong gluten( cf. grains in the field. The young larvae penetrate dough that collapses and becomes runny if more The fully developed larva may attain a length of han 5% of attacked grain is present. Steam 28 mm. Secondary effects of heavy attack by a treatment of the attacked wheat for a few seconds sordens are loss of flour yield, discoloration and (BP No. 523, 116)is beneficial in inactivating the an increased micro-organism count in the flour enzymes, which are localized near the exterior of (due to infection of the exposed endosperm the grain. The baking properties of flour milled surfaces by fungi). Attack, in Britain, is more from buggy wheat are improved by increasing the prevalent in Scotland and the north of England acidity of the dough, since the proteolytic enzyme than in the south in the bug saliva has an optimum pH of 8.5.Wheat bug damage is generally restricted to crops grown in the former Soviet Union . the mediterranean littoral, eastern Europe and the Near East Harvesting Dormancy Wheat blossom midge After the wheat appears to be ripe, it needs a The damage caused by the midge Sitodiplosis further period of maturation before it is capable mosellana varies greatly with year and locality. of germination(cf. p. 36); during this period the The female midge lays eggs in the wheat floret. wheat is said to bedormant'. Dormancy is a The feeding larvae use part of the plant juices valuable characteristic conferring a degree of for their development; in consequence, infested resistance to sprouting at harvest time. The factor grains become shrivelled. Secondary effects are appears to be related to enzymic activity; how reduced germination capacity and weight, ever, not all varieties show a period of dormancy, increased alpha-amylase activity, poorer and the factor appears to be linked genetically to baking quality of the flour. redness of bran colour
CEREAL CROPS: ECONOMICS, STATISTICS AND USES 9 tritici), Glume Blotch (Leptosphaeria nodorum Thrips tritici) . A systemic fungicide recommended against Septoria on wheat is Tilt, a triazole. Flag Smut can be controlled by seed treatment and by the growing of resistant varieties. Eelworm = Septoria nodomm) and F1ag Smut (urocYstis The larvae oftiny insects ofthe genus Hap/&,.ips and of other genera in the order Thysanoptera (‘fringe wing’), known as thrips, frequently attack the developing inflorescence of wheat in western Europe, but generally complete their development and leave the plants before the grain matures. In cold, wet harvest years, however, the adult insects occasionally fail to escape from the plant, and become occluded in the crease (cf. p. does not affect milling or baking quality of the wheat, but insects remaining in the creaSe are fragmented during milling and contribute towards the insect fragment count of the milled flour (Kent, 1969). Wheat may be attacked by the ee1wormy the worms, which are of microscopic dimensions. Infected grains are known as ‘ear cockle’ (not to be confused with ‘corn cockle’, the seeds of the weed Agrostemma githago). Wheat bug Bugs of the species Aelia rostrata and Eurygaster integriceps attack the wheat plants and puncture the immature grains, introducing with their saliva a ProteolYtic enzyme which modifies the Protein, preventing the formation of a strong gluten (cf. P. 200). Flour milled from buggy wheat gives dough that CollaPseS and becomes runny if more than 5% of attacked grain is present. Steam treatment of the attacked wheat for a few seconds (BP NO. 523,116) is beneficial in inactivating the enzymes, which are localized near the exterior of the grain. The baking properties of flour milled from buggy wheat are improved by increasing the acidity of the dough, since the proteolytic enzyme in the bug saliva has an optimum pH of 8.5. Wheat bug damage is generally restricted to crops grown Harvesting in the former Soviet Union, the Mediterranean littoral, eastern Europe and the Near East. Dormanc y After the wheat appears to be ripe, it needs a Wheat blossom midge The damage caused by the midge Sitodiplosis further period of maturation before it is capable mosellana varies greatly with year and locality. of germination (cf. p. 36); during this period the The female midge lays eggs in the wheat floret. wheat is said to be ‘dormant’. Dormancy is a The feeding larvae use part of the plant juices valuable characteristic conferring a degree of for their development; in consequence, infested resistance to sprouting at harvest time. The factor grains become shrivelled. Secondary effects are appears to be related to enzymic activity; howreduced germination capacity and seed weight, ever, not all varieties show a period of dormancy, increased alpha-amylase activity, and poorer and the factor appears to be linked genetically to baking quality of the flour. redness of bran colour. Anguina thtici, the grains becoming filled with 40: see ~i~. 1.3). ~~~~~k by thrips apparently Rustic Shoulder Knot moth The larvae of the Rustic Shoulder Knot moth (Apamea sordens) feed on the developing wheat grains in the field. The young larvae penetrate the grains at the brush end and hollow them out. The fully developed larva may attain a length of 28 mm. Secondary effects of heavy attack by A. sordens are loss of flour yield, discoloration and an increased micro-organism Count in the flour (due to infection of the exposed endosperm surfaces by fungi). Attack, in Britain, is more prevalent in Scotland and the north of England than in the south
TECHNOLOGY OF CEREALS FiG 1.3 Female thrips insect partly buried in the ventral crease of a wheatgrain. (Scanning Electon micrograph by A D. Evers, reproduced with permission of the copyright holder Leica Cambridge Ltd. Harvesting by binder Combine harvesting Wheat can be safely harvested by binder at When harvested by combine harvester, a moisture contents up to 19%, stooked in the field, machine which both cuts the stems and threshes and stored in ricks, where it will dry with the the grain, the moisture content of the wheat minimum of deterioration. However, harvesting should not exceed 15%for immediate storage,or by binder is no longer practised in the U. K. 19% if the wheat can be dried promptly Correct
10 TECHNOLOGY OF CEREALS FiG 1.3 Female thrips insect partly buried in the ventral crease of a wheatgrain. (Scanning Electon micrograph by A. D. Evers, reproduced with permission of the copyright holder Leica Cambridge Ltd.) Harvesting by binder Combine harvesting Wheat can be safely harvested by binder at When harvested by combine harvester, a moisture contents up to 19%, stooked in the field, machine which both cuts the stems and threshes and stored in ricks, where it will dry with the the grain, the moisture content of the wheat minimum of deterioration. However, harvesting should not exceed 15% for in1mediate storage, or by binder is no longer practised in the U .K. 19% if the wheat can be dried promptly. Correct