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Author Arnold, B. C.
Source CiteSeerX
Content type Text
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Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Nothofagus Solandri Var ♦ Heavy Garden Loam ♦ Histogenetic Pattern ♦ Present Investigation ♦ Material Uninfecred Root ♦ Epi-dermal Cell ♦ European Beech Fagus Sylvatica ♦ Boggy Soil ♦ Mycorrh Izal Root ♦ Root System ♦ University Grant Com-mittee ♦ Uninfected Root ♦ Un-infected Root ♦ Cross-section Mycor-rhizal Root ♦ Apical Organiza-tion ♦ Forme-acetic Alcohol ♦ Mycorrhizal Infection ♦ Acetic Alcohol ♦ Cytoplasmic Fixative ♦ Following Solution ♦ Hartig Net ♦ Nothofagus Mycorrhizas ♦ Maximum Development ♦ Fleshy Non-mycorrhizal Root ♦ Nothofagus Root ♦ Research Grant ♦ Chromium Sulphate
Abstract The character of the root system varies ac-cording to the degree of mycorrhizal infection (Arnold, 1960). Mycorrh izal roots are much branched and stunted by comparison with un-infected roots (Fig. 1). In cross-section mycor-rhizal roots are seen to be enveloped by a manrle of hyphae which penetrate in the form of a Hartig net between the radially elongated epi-dermal cells (Fig. 2). Maximum development of mycorrhizas is found where leaf-mold, moss, and humus are abundant on the forest floor, and the highest incidence of fleshy non-mycorrhizal roots is found in boggy soil, or when the tree is grown in cultivation in heavy garden loams. The present investigation was undertaken to determine whether or not the apical organiza-tion of Nothofagus mycorrhizas differed from that of uninfected roots, and to compare the histogenetic pattern of Nothofagus roots with that of the European beech Fagus sylvatica. I am indebted to the University Grants Com-mittee for a research grant in aid of this work. METHODS AND MATERIALS Uninfecred roots and mycorrhizas were fixed at fortnightly intervals throughout the year in the following solutions: tannin fixative (Johan-sen, 1940); chromium sulphate fixative (Johan-sen, 1940); cytoplasmic fixative (Marengo, 1952); forme-acetic alcohol (Johansen, 1940); Bouin 's fixative (Baker, 1950) ; acetic alcohol
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study