In ‘Diseases and pathogens of eucalypts’.

Another seven countries (namely Australia, Chile, Peru, Portugal, South Africa, Spain, Sudan, Thailand, Uruguay and Vietnam) had eucalypt cultivated areas of over 450.000 ha ( GIT Forestry Consulting, 2012 ).Species of Mycosphaerella and Teratosphaeria are the most damaging leaf pathogens in native populations and commercial stands of Eucalyptus spp., causing respectively the diseases known as Mycosphaerella Diseases (MD) and Teratosphaeria Diseases (TD) in temperate regions ( Hunter et al., 2011 ).

and leaf traits of trees of Eucalyptus globulus Labill

In the Belgian Congo, the Globulus tree has now been replaced with Eucalyptus Smithii.
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of Eucalyptus globulus with Mycosphaerella Leaf Disease

24, 1751–1757.
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Carnegie AJ, Ades PK, Keane PJ, Smith IW (1998) disease of juvenile foliage in a eucalypt species and provenance trial in Victoria, Australia.

leaf disease on Eucalyptus globulus ..

Nonetheless, oligogenic control is the most likely hypothesis to explain the discovery of just two major QTL for resistance to myco. These explained a large proportion of the phenotypic variance in family 1 and were also significant in at least one other controlled-cross family. This hypothesis is consistent with the moderate to high heritability previously reported for damage from MLD within E. globulus (narrow-sense heritability = 0.12–0.60; ; ). However, the possibility that the regions with QTL of large effect represent clusters of closely linked genes cannot be dismissed since resistance genes are commonly clustered in plants (; ; ). Due to the lack of QTL studies for disease resistance in Eucalyptus, comparative mapping is not possible. However, reported that one major gene controlled a large proportion of the phenotypic variation for rust resistance in E. grandis, which appeared to display Mendelian inheritance. In other forest trees, QTL studies have commonly found that few genomic regions explain a large proportion of the phenotypic variation in disease resistance. For example, one or two major QTL explained most of the variance in resistance to rust in poplar (; ; ; ) and pines (). Similar results have also been found in QTL studies investigating quantitative disease resistance in crop plants (reviewed by ). Hence, the control of quantitative disease resistance by one or two major loci, in combination with a few minor ancillary loci, appears representative of many pathosystems.

Photosynthesis of Eucalyptus globulus with Mycosphaerella leaf disease.
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Photosynthesis and respiration ..

, , and (2012) In: Proceeding of International Conference on The Impacts of Climate Change to Forest Pests and Diseases in The Tropics, 8 - 10 October, Yogyakarta, Indonesia

Read "Role of corticular photosynthesis following defoliation ..

THE genus Eucalyptus (Myrtaceae) forms an integral part of the Australian flora, including >800 species that dominate most forest types, from coastal to subalpine habitats (). Eucalyptus globulus (sensu ) is native to southeastern Australia, including Tasmania and the Bass Strait Islands () where it is an important component of low-altitude forest ecosystems. Eucalypts are the major hardwood species grown in pulpwood plantations throughout the world () and E. globulus is the main species grown in temperate regions ().

eucalyptus globulus leaf extract 84625-32-1

Foliar fungal pathogens from the genus Mycosphaerella affect eucalypts in natural forests and plantations worldwide. QTL analysis was conducted to dissect the genetic control of resistance in Eucalyptus globulus to a natural infection by Mycosphaerella leaf disease, using a clonally replicated outbred F2 family (112 genotypes) planted in a field trial. Two major QTL, with high LOD support (20.2 and 10.9) and high genomewide significance, explained a large proportion (52%) of the phenotypic variance in the severity of damage by Mycosphaerella cryptica, which may be indicative of oligogenic control. Both QTL were validated in a second F2 family and one was validated in a third F2 family. The mean values of different genotype classes at both major QTL argue for Mendelian inheritance with resistance dominant over susceptibility. There were strong correlations between the levels of Mycosphaerella damage in related genetic material planted in three widely separated locations in Tasmania. These findings together provide evidence that the genes controlling resistance to Mycosphaerella damage are stable in different genetic backgrounds and across different environments.