126,846 research outputs found
Combating stem and leaf rust of wheat: Historical perspective, impacts, and lessons learned
No full textmillions fed, food security, wheat rust, stem rust, leaf rust, Norman Borlaug,
Sources of resistance to yellow rust and stem rust in wheat-alien introgressions
No full textWheat is the staple food and the main source of caloric intake in most developing countries, and thereby an important source in order to maintain food security for the growing populations in those countries. Stem rust Puccinia graminis f. sp. tritici, and yellow rust P. striiformis f. sp. tritici of wheat continues to cause severe damage locally and globally, thereby contributing to food insecurity. In this paper biology and taxonomy of stem rust and yellow rust, breeding for resistance, utilization of resistance sources from different gene pools, molecular characterization and genetic dissection of resistance to rusts are discussed
Decision Support System for Soybean Rust (Phakopsora pachyrhizi) Management using QnD
No full textThe objective of this project is to design a decision support system for soybean rust management using gaming software that incorporates farmer's decision making in the face of risks from soybean rust. Learning from past actions and neighbor's actions are also incorporated. Farmers observe rust outbreak in the current and past periods and decide over how much of land to allocate between soybean, corn and other crops. This decision is influenced by maximization of expected profits criterion which entails crop rotation choices that are based upon perceived risks, yield drags and input costs from altering optimum rotation patterns. Adoption of new technology in terms of selecting better rust management practices is also analyzed in an adaptive management framework. The software meets the need of guiding policy formulation besides training stakeholders in making economically sound choices in the absence of empirical data over pest infestation.Research Methods/ Statistical Methods,
Personal Papers (MS 80-0002)
No full textCopy of letter from Harris Leon Kempner to Manley P. Rust discussing an application for an automobile
Abnormal germling development by brown rust and powdery mildew on cer barley mutants
No full textThe barley leaf rust fungus forms appressoria over host leaf stomata and penetrates via the stomatal pore. High levels of avoidance to leaf rust fungi have been described in some wild accessions of Hordeum species where a prominent wax layer on the stomata inhibits triggering of fungal appressorium differentiation. Leaf rust avoidance has not yet been found in H. vulgare. Since cuticular leaf waxes are implicated in the avoidance trait, we screened 27 eceriferum (cer) mutant lines of H. vulgare for avoidance to barley leaf rust. These mutations affect leaf waxes. Reduction in numbers of germ tubes forming appressoria over stomata was found in some lines, but the greatest reduction (ca 30%) was less than previously found in wild barley spp. or in an accession of H. chilense used here as a check. In one line (cer-zh654), avoidance was due to a combination of factors. Firstly, fewer germ tubes oriented towards stomata and so failed to contact them. Secondly, some germ tubes that encountered stomata did not form appressoria but over-grew them. In this line, therefore, the fungus tended to fail both to locate and to respond to stomata. The appressoria of barley powdery mildew form on leaf epidermal cells that they penetrate directly. On certain cer lines, a proportion of germlings of the barley powdery mildew fungus developed abnormally, suggesting that germlings failed to recognise and/or respond to the leaf surface waxes on these mutants
Morphology of the rust fungus Puccinia boroniae revisited
No full textPuccinia boroniae Henns. is a rust fungus endemic to Australia, infecting various Boronia spp. This study describes and illustrates, using light and scanning electron microscopy, the telial stage, teliospore germination and basidiospore production of specimens collected from commercial Boronia plantations in Western Australia. Unusual formation of a single basidiospore per germinating teliospore, and the pycnial stage, observed on Boronia megastigma leaves, are reported for the first time for P. boroniae
Personal Papers (MS 80-0002)
No full textLetter from Harris Leon Kempner to Manley P. Rust discussing an application for an automobile
Rust Library for Structured Stream Parallelism Programming on Multi-Cores
No full textThis is an API that simplifies the parallel programming for expressing stream parallelism on stream processing applications targeting Multi-cores.
Reference paper citation
[DOI] Pieper, R.; Griebler, D.; Fernandes, L. G. Structured Stream Parallelism for Rust. Brazilian Symposium on Programming Languages (SBLP), 2019
Search for partial resistance to leaf rust in a collection of ancient Spanish wheats
No full textA collection of 917 accessions of Spanish durum and bread wheat was screened for resistance to leaf rust (Puccinia triticina) under field conditions at three locations. Resistance levels ranged from very low to very high, high susceptibility being most frequent. Relative disease severity (referred to the most susceptible accession = 100 %) was lower than 20 % in about 6 % of the accessions in each location. In the collection most of the lines (84 %)displayed a susceptible infection type. A final selection of seven accessions (one of them durum) displaying low severity level in the field and high infection type in a growth chamber was chosen for further studies. High levels of partial resistant with longer latency period and high percentage of early aborted colonies without necrosis were found. They might be used in breeding programmes
Prospects for exploitation of disease resistance from Hordeum chilense in cultivated cereals
No full textHordeum chilense is a South American wild barley with high potential for cereal breeding given its high crossability with other members of the Triticeae. In the present paper we consider the resistance of H. chilense to several fungal diseases and the prospects for its transference to cultivated cereals. All H. chilense accessions studied are resistant to the barley, wheat and rye brown rusts, the powdery mildews of wheat, barley, rye and oat, to Septoria leaf blotch, common bunt and to loose smuts, which suggests that H. chilense is a non-host of these diseases. There are also lines resistant to wheat and barley yellow rust, stem rust and to Agropyron leaf rust, as well as lines giving moderate levels of resistance to Septoria glume blotch, tan spot and Fusarium head blight. Some H. chilense lines display pre-appressorial avoidance to brown rust. Lines differ in the degree of haustorium formation by rust and mildew fungi they permit, and in the degree to which a hypersensitive response occurs after haustoria are formed. Unfortunately, resistance of H. chilense to rust fungi is not expressed in tritordeum hybrids, nor in chromosome addition lines in wheat. In tritordeum, H. chilense contributes quantitative resistance to wheat powdery mildew, tan spot and loose smut. The resistance to mildew, expressed as a reduced disease severity, is not associated with macroscopically visible necrosis. Hexaploid tritordeums are immune to Septoria leaf blotch and to common bunt although resistance to both is slightly diluted in octoploid tritordeums. Studies with addition lines in wheat indicate that the resistance of H. chilense to powdery mildew, Septoria leaf blotch and common bunt is of broad genetic basis, conferred by genes present on various chromosomes
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