Temperature-sensitive genes for resistance to Puccinia striiformis in Triticum dicoccoides

Summary Twenty-six selections of wild emmer collected at different sites in Israel and three entries obtained from Turkey were studied for the possible presence of temperature-sensitive genes controlling reaction to Puccinia striiformis. In tests carried out in Israel with a local P. striiformis isolate at two temperature regimes, 16 selections showed a change in infection rating toward resistance at the higher temperature regime. In comparable tests performed in the United States with a Montana P. striiformis isolate of different virulence pattern-including 14 of the same selection—ten entries displayed a temperature-sensitive reaction. Although slightly different temperature regimes were used in Israel and the United States, the results obtained were in general agreement. The shift toward resistance observed in the seedling tests at the higher temperature-profile was also evident in the field in the mature plant stage with increasing spring temperatures.     

Joint Selection for High Yield and Low Sensitivity in Winter Wheat (Triticum aestivum L.)

Early generation yield trials of families from a set of winter wheat crosses were grown in three contrasting environments chosen to represent differences in two important macro-environmental variables affecting the wheat, crop in Eastern England. Joint selection for high yield and low sensitivity to these macro-environmental variables over two seasons using the procedure of Brumpton et al. (1977) resulted in a group of genotypes which exhibited a much wider yield range than would have resulted from selecting for yield in each -environment separately. In spite of this, the top performing lines an yield trials grown in each of the environments during the next season exhibited good yield and stability over all three environments, demonstrating the feasibility of such a method for winter wheat breeding.     

The Changing Scale of Livestock Production in and around Corn Belt Metropolitan Areas, 1978–97

This research examines changes in four sectors of livestock production, pork, dairy, fed cattle, and beef cows, from 1978 to 1997 by county metropolitan character. Relative changes in the amount of production and the number of producers in a county as well as changes in the average scale of production are examined. The purpose is to identify whether structural differences have emerged between metropolitan and nonmetropolitan Corn Belt counties as a result of industrialization in livestock production. The analysis identifies a divergence in the amount and scale of pork production in metro versus nonmetro regions from 1987 to 1997, coinciding with a period of substantial industrialization in that sector. Little divergence is identified in the scale of dairy, fed cattle, and beef cows operations during the same time period. The findings have implications for farmland preservation and agricultural viability in exurban regions of the Corn Belt.     

Acute aldicarb toxicity in dogs: 15 cases (2001–2009)

Objective – To describe the common clinical signs, laboratory abnormalities, treatment, and prognosis associated with acute aldicarb toxicosis in dogs. Design – Retrospective observational study from 2001 to 2009. Setting – Urban referral hospital. Animals – Fifteen client‐owned dogs. Interventions – None. Measurements and Main Results – The most common clinical signs associated with acute aldicarb toxicosis were vomiting, ptyalism, diarrhea, and tremors. Of the 15 dogs, 11 were admitted to the hospital for treatment, 2 were euthanized at presentation and 2 were discharged against medical advice following minimal treatment and lost to follow‐up. Laboratory abnormalities included lactic acidosis and hyperglycemia in 12 and 9 patients, respectively. Treatment of hospitalized dogs included induction of emesis with apomorphine (4 dogs), activated charcoal (5), IV fluids (11), atropine (7), methocarbamol (3), diazepam (1), pralidoxime (1) and diphenhydramine (1). Ten of 11 hospitalized dogs survived to discharge; 1 was euthanized following a respiratory arrest after 36 hours of hospitalization. One patient received mechanical ventilation and treatment for pneumonia before discharge from the hospital. The median duration of hospitalization was 22 hours (range 12–168 h). Conclusions – Acute aldicarb toxicosis carries a good prognosis for survival and hospital discharge with treatment. Supportive care should be considered for at least 18–24 hours to monitor for response to therapy and development of respiratory failure.     

Inoculation of growing media with the rhizobacterium Variovorax paradoxus 5C-2 reduces unwanted stress responses in hardy ornamental species

Inoculation of growing media with plant growth promoting rhizobacteria (PGPR) has a number of potential benefits for the production of ornamental plants. Certain rhizobacteria synthesise the enzyme ACC deaminase, which cleaves ACC, the precursor of the plant hormone ethylene. Bacterial metabolism is now known to lead to a reduction in [ACC] in the plant transpiration stream and bacteria are hypothesised to act on ACC exuded from roots. This in turn reduces the ethylene generated in plants growing in growing media inoculated with these bacteria. Here we tested if applications of the ACC deaminase containing rhizobacteria Variovorax paradoxus⁵C–²could be of benefit to ornamental growers by reducing ethylene generation in stressed plants. Ethylene is produced at levels that are inhibitory to growth and development under a number of abiotic stresses. The propagation and production of hardy ornamentals is deleteriously affected by abiotic stresses that involve ethylene signalling, including drought and physical wounding. Inoculation of growing media with V. paradoxus 5C-2 lowered ethylene emission from mature leaves of Cytisus × praecox experiencing drought stress. In addition, bacterial inoculation of the growing media resulted in significantly reduced abscission of the mature leaves under drought treatment. Beneficial effects of inoculation where also found in the wounding response of Fargesia murielae following divisional propagation and late season senescence in Aquilegia × hybrida in response to drought stress. Together these results demonstrate that V. paradoxus⁵C–²has real potential for use on ornamental nurseries in situations where plant stresses are unavoidable.     

Production of all eight genotypes of null alleles at 'waxy' loci in bread wheat, Triticum aestivum L.

Null alleles of the three loci coding for ‘waxy’ proteins in bread wheat have been identified. Plants carrying different null alleles were collected and segregation of the null alleles in both selfed and doubled haploid progeny of plants simultaneously heterozygous for the null alleles at each of the three loci were examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Mendelian segregation of these alleles in both types of progeny was shown, indicating that they can easily be utilized in breeding programmes. Iodine staining of the eight possible null phenotypes showed that only the triple null type had zero amylose in its endosperm starch.     

Spinal Root Origin of the Radial Nerve and Nerves Innervating Shoulder Muscles of the Dog

The ventral spinal root origin of the radial nerve, its muscle branches, and brachial plexus nerves which supply shoulder and thoracic musculature was determined in the dog. Electrophysiological signal averaging techniques measured evoked potential from specific ventral spinal roots to individual muscle nerves. The entire radial nerve received input from the sixth cervical (C6) through the second thoracic (T2) spinal roots. The most significant (p less than .05) input to triceps brachii came from C8 while the deep ramus of the radial nerve received its largest input from C7. The brachiocephalicus, suprascapular, and subscapular nerves all received their most significant (p less than .05) innervation from C6. Approximately 90% of the evoked potential to the axillary nerve originated from C7. The thoracodorsal nerve received most of its innervation from ventral roots C7 and C8. The lateral thoracic nerve which innervates the cutaneous trunci muscle was supplied by ventral roots C8-T2. Examination of innervation patterns suggests that only modest variation of spinal root input to specific nerves occurred between individual dogs.