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(= Septoria8 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 import￾ance 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 ~~~il￾to 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 charac￾ter for immunity was recessive, appearing in one￾obfiterated 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 genera￾develop 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 recom￾Of 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 Pseudocercos￾caries. 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 succes￾flotation (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