Showing papers on "Rust published in 1987"

The association of a gene for leaf rust resistance with the chromosome 7D suppressor of stem rust resistance in common wheat

Abstract: Backcross lines of gene LrT2 for resistance to leaf rust in the common wheat (Triticum aestivum L.) 'Thatcher' unexpectedly show improved resistance to stem rust compared with that of the recurrent parent. Genetic–cytogenetic evidence indicates that LrT2 is on chromosome 7D, which is known to carry the "suppressor" gene(s) that prevent the expression of stem rust resistance conferred by other genes in 'Canthatch'. Thus, LrT2 may be a nonsuppressing allele of the suppressor gene(s) or be closely linked to such an allele. LrT2 has been designated Lr34. Key words: Triticum, wheat, rust resistance.

Effect of crown rust on regrowth, competitive ability and nutritional quality of perennial and Italian ryegrasses

Abstract: Infection of susceptible cultivars of perennial (Lolium perenne) and Italian (Lolium multiflorum) ryegrasses with crown rust (Puccinia coronata) reduced yield measured 6 weeks after infection and at two regrowth cuts. In perennial, but not Italian, ryegrass, rust infection of mixed swards of a resistant and a susceptible cultivar reduced the contribution to yield made by the susceptible cultivar and increased that of the resistant cultivar. This effect persisted for three regrowth cuts. The trend in effect on the number of tillers, but not plant height, was similar. Infection increased leaf protein in susceptible perennial ryegrass but had little effect in Italian ryegrass. In both species, rust reduced water-soluble carbohydrate and the predicted digestibility of susceptible and resistant cultivars, but had no effect on quality of regrowth.

The effect of film‐forming anti‐transpirants on leaf rust and powdery mildew incidence on wheat

Abstract: Various film-forming anti-transpirants effectively controlled leaf rust and powdery mildew on wheat in the field. Two applications of anti-transpirant emulsions applied after flag leaf emergence were sufficient to suppress leaf rust and powdery mildew on wheat leaves. When applied before, but not after, inoculation anti-transpirant polymers also reduced leaf rust on seedling plants in a growth room experiment.

The formation of pyrophoric iron sulphide from rust

Abstract: Hydrogen sulphide present in crude oil can react with rust in the cargo tanks of oil tankers to give iron sulphide. The particular form of the sulphide produced depends on the temperature, the availability of hydrogen sulphide and the time of the reaction. As the concentration of pyrite increases, so does the pyrophoric tendency and the possibility of explosions.

Interference between rust (puccinia lagenophorae cooke)-infected and healthy groundsel (senecio vulgaris l.)

Abstract: Populations of groundsel (Senecio vulgaris L.) were grown in the field in bottomless containers which allowed roots to penetrate freely into the natural soil profile. The 36 plants within each population (equivalent to 1250 m-2) were either all inoculated with the rust Puccinia lagenophorae Cooke, all rust free, or were a 1:1 mixture of the two. Rain was excluded from all populations by small shelters. Half the populations were subjected to mild drought, whilst remaining populations were well-watered. Rust significantly reduced shoot dry weights, especially in droughted populations. The frequency distributions of shoot dry weight showed significant inequality (were strongly skewed) in all treatments and populations. Inequality of the frequency distribution of shoot dry weight was increased in rusted populations because infection increased the proportion of suppressed individuals. Again the effect of rust was most pronounced under conditions of drought and particularly in mixture. Rust significantly lowered mean shoot water potential (3k) in dry monocultures and in both wet and dry mixtures. Values of i/ at harvest in suppressed, rusted individuals in mixtures were often highly negative. Compared with dry monocultures, water stress in mixtures was ameliorated in the healthy, but exaggerated in the rusted, components. The more negative values of if in rusted populations were the result of changes in frequency distributions as well as in mean values. Under dry conditions status in the dry weight hierarchy was closely correlated with if. These changes are interpreted as reflecting the reduced ability of the root systems of rusted plants to compete for limited water. The competitive ability of control over rusted groundsel, as measured by relative crowding coefficient (Kcr), was 1 09 under well-watered conditions but increased to 1-51 under drought. In both well-watered and droughted populations, the greater impact of rust on the population hierarchy of mixtures was reflected in the inverse relationship between the status of sub-classes, based on shoot weight and class Kcr It is concluded that water stress probably plays a crucial role in determining the impact of rust on mixed populations in the field.

Composition for rust removal and method of use thereof

Abstract: A non-phosphate cleaning composition, having enhanced rust removal properties at ambient temperatures, comprising oxalic acid and an activating amount of ferrous ion. This formulation removes rust better than formulations not containing the activating amount of ferrous ion.

Water-stress modifies intraspecific interference between rust (Puccinia-Lagenophorae Cooke)-infected and healthy groundsel (Senecio-Vulgaris L)

Abstract: SUMMARY Populations of groundsel (Senecio vulgaris L.) were grown in the field in bottomless containers which allowed roots to penetrate freely into the natural soil profile. The 36 plants within each population (equivalent to 1250 m−2) were either all inoculated with the rust Puccinia lagenophorae Cooke, all rust free, or were a 1:1 mixture of the two. Rain was excluded from all populations by small shelters. Half the populations were subjected to mild drought, whilst remaining populations were well-watered. Rust significantly reduced shoot dry weights, especially in droughted populations. The frequency distributions of shoot dry weight showed significant inequality (were strongly skewed) in all treatments and populations. Inequality of the frequency distribution of shoot dry weight was increased in rusted populations because infection increased the proportion of suppressed individuals. Again the effect of rust was most pronounced under conditions of drought and particularly in mixture. Rust significantly lowered mean shoot water potential (ψ) in dry monocultures and in both wet and dry mixtures. Values of ψ at harvest in suppressed, rusted individuals in mixtures were often highly negative. Compared with dry monocultures, water stress in mixtures was ameliorated in the healthy, but exaggerated in the rusted, components. The more negative values of ψ in rusted populations were the result of changes in frequency distributions as well as in mean values. Under dry conditions status in the dry weight hierarchy was closely correlated with ψ These changes are interpreted as reflecting the reduced ability of the root systems of rusted plants to compete for limited water. The competitive ability of control over rusted groundsel, as measured by relative crowding coefficient (Ker), was 1–09 under well-watered conditions but increased to 1˙51 under drought. In both well-watered and droughted populations, the greater impact of rust on the population hierarchy of mixtures was reflected in the inverse relationship between the status of sub-classes, based on shoot weight and class Ker. It is concluded that water stress probably plays a crucial role in determining the impact of rust on mixed populations in the field.

Interactions of the bean rust and cowpea rust fungi with species of the Phaseolus – Vigna plant complex. I. Fungal growth and development

Abstract: Growth and development of two closely related rust fungi, Uromyces appendiculatus and U. vignae (uredospore infections), were compared in several American and African species of the Phaseolus – Vig...

Histological studies on the infection of triticale, wheat and rye by Puccinia recondita f.sp. tritici and P. recondita f.sp. recondita.

Abstract: The reaction of eight triticales and of the respective wheat and rye parental lines to infection by the leaf rust fungi of wheat and rye were studied in the seedling stage. The histological observations indicated that wheat and triticale showed a typical nonhost reaction to the leaf rust of rye: sporelings of this fungus were arrested after the formation of primary infection hyphae and before the formation of extensively branched mycelium, mostly without necrosis of plant cells. The rye inbred lines were all susceptible to the rye leaf rust. The reaction of wheat and triticales to the wheat leaf rust was susceptible or resistant. The reaction of resistant lines could be early or late and complete or incomplete, but was associated with substantial necrosis of plant cells, and therefore entirely different from the nonhost reaction to rye leaf rust. In their reaction to wheat leaf rust the rye lines were similar to the resistant wheat and triticale lines. They did not show an important degree of nonhypersensitive early abortion as would be expected in a nonhost species. It appeared that genes for hypersensitive resistance in triticale may be contributed by either the wheat or the rye parental line. A screening of sixty wheat, rye and triticale lines confirmed the nonhost status of wheat and triticale to rye leaf rust and the hypersensitive or moderately susceptible reaction of rye to wheat leaf rust.

Groundnut rust disease: epidemiology and control.

Abstract: Research on rust disease of groundnut at ICRISAT Center from 1976 to 1984 is briefly reviewed. Spread of the disease in India is documented, and the role of continuous cultivation of groundnut in perpetuating the disease emphasized. Data on yield losses from rust are presented. Methods of screening germplasm and breeding lines for resistance to rust are described, and the identified sources of resistance are listed. Components of resistance to rust and their possible use in greenhouse evaluation of rust resistance are discussed. Results of multilocation testing of rust-resistant germplasm lines are considered. The effects of different agronomic systems on epiphytotics of rust are discussed.

Somaclonal Variation For Rust Resistance in Sugarcane

Abstract: Callus was produced from leaf explaints of a sugracane variety susceptible to rust disease caused by Puccima melanocephala H. & P. Syd. Whole plants were differentiated from the callus after subculture. A total of 260 plants were established in the field. They were screened for rust resistance. One somaclone was found to be resistant to the disease. This done is now undergoing adaptability trials. A second cycle of somaclones was produced from the callus derived from the explants of the resistant plant. These plants, numbering 308, were free of rust infection, indicating the stability of the change from susceptibility to resistance.

Rust conversion coatings

Abstract: Revue de la technologie courante des produits de conversion de la rouille detaillant les performances de ces produits sur des substrats ayant differents degres et types de rouille. Resultats experimentaux d'essais de corrosion des couches de conversion obtenues sur les aciers AISI1010 et 1020

Rust preventive treatment for iron and steel products

Abstract: PURPOSE:To form a rust preventive film having good and uniform quality by continuously executing an underlying treatment stage in which iron and steel products are subjected to degreasing and pickling then to washing and drying, rust preventive film sticking stage in which the iron and steel products are immersed in a soln mixture composed of caustic soda, sodium nitride, potassium chloride and sodium bicarbonate and are cooled and finish treatment stage in which oil is stuck thereto CONSTITUTION:The iron and steel products are subjected to degreasing then to pickling by a dilute hydrochloric acid contg ferric iron oxide followed by washing and drying as the underlying treatment stage The dried steel products are immersed for 12min in the heated soln mixture composed of 70% caustic soda, 15% sodium nitrite, 13% potassium chloride and 2% sodium bicarbonate and are cooled as the rust preventive film sticking stage The oil is coated on the surface of the iron and steel products as the final stage The rust preventive iron oxide film having the good and uniform quality is formed by the above-mentioned constitution

Paint for inhibiting rust staining

Abstract: External rust-staining, for example at the exterior of buildings or on the superstructure or topside of ships, caused by rust dripping onto a surface is inhibited by painting the surface with a top-coat paint comprising a film-forming binder and a substance capable of reacting with rust to form a colorless material. The said substance can for example be a polyphosphonate salt pigment, an oxalate or a glass releasing phosphate ions.

Novel oleaginous composition additives for improved rust inhibition

Abstract: According to the present invention, oleaginous compositions having improved rust inhibitions properties are provided, which comprise a combination of ashless dispersants, rust inhibitor and oil-soluble copper carboxylate antioxidants, wherein the composition is substantially free of boron.

Rapid forming of weather resisting anti-rust film on steel

Abstract: It is for special steel or ordinary carbon steel The adoptions of tannin extract, which reduces or even replaces the industrial digallic acid used in the existing technique, and of metal-salt as accelerating agent, not only enable, as the existing technique does, the surface of the steel to form a weather resisting anti-rust film which is well crystallized, compact and sparsely microporous, providing steel materials with better corrosion-resistance ability under corrosive conditions, but also expand the sources of raw materials, reduce production costs by 40 to 50% as compared with the existing technique, and notably increace the corrosion resistant ability of the anti-rust film against chlorine ions