Nutrient requirements of suspension cultures of soybean root cells.

Biological and Phytochemical Screening of Plants

The latest previous comprehensive review of allelopathy (Rice, 1974) covered research done primarily prior to 1973. There have been numerous reviews published in recent years on specific phases of allelopathy (see III), but most of them covered research results published primarily through 1972 also. This review has been restricted, therefore, largely to research conducted subsequent to 1972, except for background information and significant papers overlooked in previous reviews. There has been almost an exponential increase in the rate of publication of papers concerned with allelopathy. Research has been particularly active in relation to the roles of allelopathy in agriculture, forestry, phytopathology, patterning of vegetation, algal succession, and old-field succession. Our increasing knowledge of the conditions under which certain crop residues cause allelopathic effects to subsequent crops should enable us soon to guard against such effects. We are on the threshold of breeding crop plants that will inhibit the chief weeds in a given area through allelopathic action, and thus decrease the need for synthetic weed killers. Our understanding of allelopathic interactions of various plant species has already been used advantageously in reforestation, and future developments are very encouraging. Our increasing knowledge of allelopathy is aiding greatly in our understanding of many ecological phenomena, such as succession and patterning of vegetation. Evidence is mounting that inhibition of nitrification increases as succession progresses toward the climax vegetation, at least in many vegetation types. This leads to a decrease in the loss of nitrogen. Addition of inhibitors to arable lands to prevent nitrification has proved to be valuable in preventing loss of nitrogen and in increasing crop yields. There has been a rapid advance in our knowledge of mechanisms of action of known allelopathic compounds, at increasingly more fundamental levels. We have known for several years, for example, that some of these compounds inhibit uptake of various minerals, but have not known the mechanism of the action. Recent research indicates this may be due, at least in part, to inhibition of a plasma membrane ATPase that is involved with ion absorption. A thorough knowledge of mechanisms of action of allelochemics is essential to our overall understanding and appreciation of the field of allelopathy.

Allelopathy—An update

Antibacterial activity of some folklore medicinal plants used by tribals in Western Ghats of India.

Publisher Summary The purpose of this chapter is to present data and discusses cell-wall protein from several points of view ranging from the purely enzymic aspects (cell-wall enzymes) to the structural hydroxyproline-rich wall proteins. Although the subject of wall protein is hardly a new field it does begin to look as though the demonstration of wall-bound hydroxyproline has imparted a revivifying stimulus to an old problem-this is more evident from work known to be in progress than from the amount of published material. Physically and chemically, the anisotropic cambial walls contain both cellulose and polyuronides. Electron microscopic studies show that more or less randomly interwoven cellulose microfibrils are recognized as another definitive characteristic of primary cell walls. Isolation of a clean wall fraction from various parts of whole plants is much more difficult than from suspension cultures. An important point is that the primary wall is often contaminated with secondary wall. This increases the difficulty of cell breakage and removal of the cell contents.

The Protein Component of Primary Cell Walls

Numerous surveys have demonstrated the wide occurrence of active antimicrobial substances in higher plants. The array of compounds with unique structures which plants produce has served as a stimulus to continued search for useful antibiotics. Reports referred to in the table indicate that active substances have been found in plants from 157 families.

Antimicrobial activity of vascular plants

The growth rate of plant tissue cultures is substantially increased through the use of a large-volume carboy system. Aeration is considered to be the most important factor. With this system, yields of a pound or more of tissue can be obtained within 2 weeks.

https://science.sciencemag.org/content/sci/130/3379/863.full.pdf

Production of Large Amounts of Plant Tissue by Submerged Culture

https://www.pnas.org/content/pnas/42/11/848.full.pdf

The continuous submerged cultivation of plant tissue as single cells

Section of biological and medical sciences: methods, problems, and results of growing plant cells under submerged conditions*

The submerged propagation of plant tissue and cell cultures has now reached the stage where mass amounts of material can be produced. In discussing these advances, various aspects of the technology involved are discussed: the methods of isolation and establishment of cultures, the media used for culture and their effects on growth, the systems used for growth and a comparison of their effectiveness.

Biochemical differences are shown between cultures grown under in vitro conditions and the organ from which they were derived. These differences are found among amino acids, organic acids, nucleic acids, and sugars. The potential use of the tissue culture approach for the study of the biosynthesis of ‘secondary compounds’ such as alkaloids and steroids is discussed.

Louis G. Nickell

Papers

Antimicrobial activity of vascular plants

Production of Large Amounts of Plant Tissue by Submerged Culture

The continuous submerged cultivation of plant tissue as single cells

Section of biological and medical sciences: methods, problems, and results of growing plant cells under submerged conditions*

Submerged growth of cells of higher plants