ABSTRACT
Coiled, viruslike particles (spirions) were detected by electron microscopic examination of crude extracts from flowers, leaves, and/or roots of infected Prunus avium, P. mume, and P. serrulata. The particles were observed in ultrathin sections of lower epidermis, palisade, and spongy mesophyll cells of leaves of P. avium and P. mume. Spring (March and April) appears to be optimal for detection of the particles in both screenhouse and field-grown plants. The particles were successfully graft-transmitted to P. armeniaca (cvs. Luizet and Tilton), P. avium (cvs. Bing, F12/1, Mazzard, and Sam), P. mahaleb, and P. persica (cv. Elberta). Individual spirions measured 132 × 34 nm. The particles appear to be coiled forms of a filamentous virus. Filaments extending from some coiled particles were approximately 13 nm wide, with striations at a pitch of 3.24 nm. No disease symptoms or cytopathological abnormalities were associated with the presence of the particles in the Prunus species studied. The particles were not detected in virus-free control plants.
ABSTRACT
A recessive temperature dependent shooty mutant (tds) of Nicotiana tabacum L. (W38) is described. The mutant phenotype is expressed at low temperature (21 degrees C). Mutant characteristics include thick, narrow leaves with abnormal mesophyll cells, short internodes, and near absence of apical dominance. Most plants remain vegetative and the occasional flower has petaloid stamens. High temperature (30 degrees C) reverses the mutant phenotype, with formation of normal leaves and restoration of apical dominance. However, many flowers still have petaloid stamens. Reciprocal grafting and auxincytokinin interaction experiments do not suggest shifts in auxin-cytokinin balance. Overall, this mutant bears some resemblance to transgenic tobacco overexpressing homeodomain genes from maize and Arabidopsis.
Subject(s)
Plants/analysis , Polysaccharides/analysis , Amylases , Animals , Aspergillus , Chromatography, DEAE-Cellulose , Chromatography, Gel , Chromatography, Ion Exchange , Cytophaga , Enterobacter , Glucose/analysis , Glycoside Hydrolases , Iodine , Molecular Conformation , Pancreas/enzymology , Spectrophotometry , SwineSubject(s)
Cytoplasm/metabolism , Glycogen/metabolism , Plant Cells , Animals , Ants , Biological Evolution , Cell Differentiation , Cell Division , Chloroplasts/metabolism , Food , Glycogen/biosynthesis , Histocytochemistry , Microscopy, Electron , Photomicrography , Plant Development , Plant Physiological Phenomena , Plants/metabolism , Polysaccharides/metabolism , TreesABSTRACT
A glycogen-containing plastid has been found in the cells of Müllerian bodies on Cecropia peltata (Moraceae) trees. Plastids in cells of the leaf blade, petiole, and stem are of the usual chloroplast type and contain starch grains only. Müllerian bodies exist for the purpose of providing a food supply for a protective, mutualistically inhabiting ant population. A series of chemical tests and observations indicates that this glycogen is identical to animal glycogen.
