745 research outputs found
Selection for resistance against root pathogens in a pea composite cross
The possibility of improving resistance in pea against the root pathogen Aphanomyces euteiches using composite cross as a breeding and selection method was examined. In order to maintain acceptable agricultural features and high yield 6 out of the 8 parental varieties in the present composite-cross were commercially grown varieties. Populations of the composite cross were grown up to five generations with selection pressure in soil heavily infested with pea root pathogens or without selection pressure on soil free of pea root pathogens. Yield of populations of the F9 and F10 generations of the composite cross grown with selection pressure was on average 35% higher than that of the population obtained without selection pressure as well as the average yield of the 8 parentals of the composite cross, which were of similar magnitude. In healthy soil the yield was overall higher than in the pathogen-infested soil, but yield did not differ between the populations from the composite cross with and without selection pressure, which were also similar to the average yield of the 8 different parentals. Recombinant inbred lines (RILs) randomly selected from the F10 population with selection pressure developed 23% less root rot than the corresponding F10 population without selection pressure, when grown in field soil heavily infested with pea root pathogens. Surprisingly, greenhouse pot experiments with pure cultures of the pea root pathogen A. euteiches resulted in higher root disease, in RILs from populations with selection pressure than from corresponding RILs without selection pressure. Problems related to greenhouse screening for resistance is discussed as well as the possibilities of using composite cross as a method to improve resistance against root diseases in grain legumes
Specificity of soil-borne pathogens on grain legumes
Specificity of soil-borne legume pathogens on pea, lupin and faba bean is currently investigated in fields where grain legumes are intensively cultivated.
The study has so far lead to the following conclusions
-Legume host-pathogen interactions demonstrate specificity of pathogen populations particularly in pea and lupin.
-A. euteiches rot root was specified to pea in Denmark as root rot symptoms and oospores of the pathogen never were observed in roots of faba bean and lupin
-F. oxysporum followed by F. solani were most frequently isolated from plant roots in plots highly infested by lupin pathogens
-F. avenaceum was most frequently isolated from plant roots in plots highly infested by pea pathogens
-Pathogenicity tests showed F. solani followed by F. avenaceum to be the most pathogenic Fusarium species on pea while F. avenaceum was the most destructive pathogen on faba bean. In contrast F. avenaceum was non-pathogenic on lupin
Denmark:the long-lasting class compromise
Purpose
The purpose of this paper is to offer a critical examination of industrial relations in Denmark.
Design/methodology/approach
The approach is based upon available data and a mixture of Marxist theory and systems theory. The theoretical position is discussed in relation to the academic discourses on the main characteristics of Danish industrial relations and provides a review of the foundation and historical development of the Danish system.
Findings
From this basis, it is analysed how the stagnation or decline has taken place in recent years regarding representation of workersâ interest as well as the ability of the Danish system to maintain its key importance when challenged by decentralisation, decreasing union affiliation rates, cuts in unemployment insurance and social dumping due to labour migration.
Originality/value
It is an original paper which offers a critical analysis of the institutional decline and increasing inequality that are the result of the liberalist political-economic hegemony.
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Impaired transmission in the corticospinal tract and gait disability in spinal cord injured persons
Rehabilitation following spinal cord injury is likely to depend on recovery of corticospinal systems. Here we investigate whether transmission in the corticospinal tract may explain foot drop (inability to dorsiflex ankle) in persons with spinal cord lesion. The study was performed in 24 persons with incomplete spinal cord lesion (C1 to L1) and 15 healthy controls. Coherence in the 10- to 20-Hz frequency band between paired tibialis anterior muscle (TA) electromyographic recordings obtained in the swing phase of walking, which was taken as a measure of motor unit synchronization. It was significantly correlated with the degree of foot drop, as measured by toe elevation and ankle angle excursion in the first part of swing. Transcranial magnetic stimulation was used to elicit motor-evoked potentials (MEPs) in the TA. The amplitude of the MEPs at rest and their latency during contraction were correlated to the degree of foot drop. Spinal cord injured participants who exhibited a large foot drop had little or no MEP at rest in the TA muscle and had little or no coherence in the same muscle during walking. Gait speed was correlated to foot drop, and was the lowest in participants with no MEP at rest. The data confirm that transmission in the corticospinal tract is of importance for lifting the foot during the swing phase of human gait
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