Pod utjecajem virusa ižljebljenosti stabla jabuke (apple stem pitting virus) nastaju u drvu indikatora Virginia Crab male žljebaste udubine koje se podudaraju s odgovarajućim izbočinama floema. Čini ...se da virus osobito oštećuje područje kambija i poremećuje normalno diferenciranje kambijskih stanica.
Pod utjecajem virusa dolazi u floemu u području žljebastih udubina do kolabiranja sitastih cijevi, povećanja broja stanica floemskog parenhima, nakupljanja oksalatnih kristala te do poremećaja u građi trakova srčike i u diferenciranju likovnica. Inicijalne stanice kambija mogu biti u području udubine zamijenjene drugim parenhimskim stanicama.
U istim radij ušima u kojima nalazimo promjene u floemu dolazi do promjena i u drvu. Anomalno drvo izgrađeno je uglavnom od izmijenjenih stanica drvnog parenhima, povećanih trakova srčike, iskrivljenih vlakanaca libriforma, a traheje su malobrojne ili čak izostaju.
A bridge over troubled water Gundersen, Vegard; Kaltenborn, Bjørn P; Williams, Daniel R
Norsk geografisk tidsskrift,
2016, Volume:
70, Issue:
4
Journal Article
The concept of Floer homology was one of the most striking developments in differential geometry. It yields rigorously defined invariants which can be viewed as homology groups of ...infinite-dimensional cycles. The ideas led to great advances in the areas of low-dimensional topology and symplectic geometry and are intimately related to developments in Quantum Field Theory. The first half of this book gives a thorough account of Floer's construction in the context of gauge theory over 3 and 4-dimensional manifolds. The second half works out some further technical developments of the theory, and the final chapter outlines some research developments for the future - including a discussion of the appearance of modular forms in the theory. The scope of the material in this book means that it will appeal to graduate students as well as those on the frontiers of the subject.
