Margaret E. McCully

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1. The polychromatic staining of plant cell walls by toluidine blue O is described and illustrated. 2. The effects of various common fixatives and the effects of the pH of the staining solution are evaluated. 3. Simple and rapid procedures are described for preparing stained temporary mounts of fresh material, or permanent mounts of embedded and sectioned(More)
An optical brightener Calcoflour White M2R New has been used to stain cell walls of higher plants. It can be used either as a vital stain for intact plants or for hand sections and plastic-embedded thin sections. Walls are brilliantly fluorescent while most cytoplasmic components are normally unstained. The brightener binds strongly to cellulose,(More)
The root system of a plant is as complicated as the shoot in its diversity, in its reactions with the matrix of substances, and with the myriad organisms that surround it. Laboratory studies blind us to the complexity found by careful study of roots in soil. This complexity is illustrated in the much-studied corn root system, covering the changes along the(More)
Field observations have shown that rhizosheaths of grasses formed under dry conditions are larger, more coherent, and more strongly bound to the roots than those formed in wet soils. We have quantified these effects in a model system in which corn (Zea mays L.) primary roots were grown through a 30-cm-deep prepared soil profile that consisted of a central,(More)
Storage of phosphorus (P) in stem tissue is important in Mediterranean Proteaceae, because proteoid root growth and P uptake is greatest during winter, whereas shoot growth occurs mostly in summer. This has prompted the present investigation of the P distribution amongst roots, stems, and leaves of Hakea prostrata R.Br. (Proteaceae) when grown in nutrient(More)
Nitrogen-fixing bacteria, isolated from the sugar solution in intercellular spaces of sugarcane stems, were compared with the type strain of Acetobacter diazotrophicus (PAL-5) and found to be congruent with it in all characters studied. These characters were 37 morphological and biochemical tests, cellular fatty acid composition, and nitrogenase activity.(More)
The intercellular spaces of sugarcane (Saccharum officinarum L.) stem parenchyma are filled with solution (determined by cryoscanning microscopy), which can be removed aseptically by centrifugation. It contained 12% sucrose (Suc; pH 5.5.) and yielded pure cultures of an acid-producing bacterium (approximately 104 bacteria/mL extracted fluid) on N-poor(More)
Mucilages from the root tips of axenically-grown maize and from a bacterium (Cytophaga sp.) isolated from the rhizosheaths of field-grown roots, were immobilized by drying onto nylon blotting membrane. The mucilage plaques remained in place through repeated rewettings and histochemical treatments. Staining of the plaques showed that both mucilages included(More)
Recent work in our laboratory provides evidence for a revised view of the functioning of roots of maize, and probably of all the grasses. The development of coherent soil sheaths on the distal 30-cm of these roots, and the loss of the sheaths further back, led us to investigate the differences in surface structure, anatomy, carbon exudation and microflora(More)
Deep root systems that extend into moist soil can significantly increase plant productivity. Here, the components of soil-grown root systems of wheat, barley and triticale are characterized, and types and water conducting potential of deep roots in the field are assessed. Root system components were characterized in plants grown in soil in PVC tubes, based(More)