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The effect of coumarin, IAA, ethylene, kinetin and gibberellic acid on roots of maize and wheat was investigated. Sterile attached and detached roots and isolated elongation zones were used. In some experiments a semi-sterile procedure was followed. The effects of the different regulators separately or in various combinations together with coumarin were studied on the root growth with regard to division, elongation and swelling of the cells, The ethylene production in isolated elongation zones was measured after treatment with coumarin, IAA, PCIB, kinetin, colchicine and dinitrophenol. The results show the following: 1) Each substance produces a specific morphologic pattern. 2) Changes in polarity were demonstrated for auxin-induced swelling in cell divisions and cell expansion and for coumarin-induced swelling in cell division. Other cell expansion in swollen parts was due to cylindric cells increasing in width while retaining their cylindric form. 3) Coumarin-induced inhibition could not be counteracted by IAA, PCIB, carbon dioxide, kinetin, gibberellic acid or Cycocel. 4) The ethylene production in isolated elongation zones increases noticeably after kinetin treatment, less strongly after auxin treatment and least after coumarin treatment. The production of ethylene does not seem to be correlated with the morphogenetic effect of the different substances. 5) The isolated elongation zones reacted to a) IAA and kinetin with an increase in length in some cases and b) gibberellic acid with a reduction of their width. 6) The inhibitory effect of coumarin on the growth in length of the elongation zones was diminished by kinetin. The swelling produced by coumarin in these zones was reduced by gibberellin acid. The effects just mentioned of kinetin and gibberellic acid. The effects just mentioned of kinetin and gibberellic acid were considered as indirect ones. — From the present finding it was concluding that concomitant effects of auxin, ethylene, cytokinins and gibberellins are not obligatory are not obligatory for coumarin to exert its morphogenetic effects on root growth. In discussing the results some pitfalls in studies of growth reactions after application of hormones to roots containing meristem were emphasized. [ABSTRACT FROM AUTHOR]

A portable freezing point meter was used in the field to measure the water potential gradients in sunflower (Helianthus annuus), beans (Phaseolus vulgaris), corn (Zea mays), wheat (Triticum aestivum), pumpkin (Cucurbita pepo), potato (Solanum tuberosum), alfalfa (Medicago sativa), and sugarbeets (Beta vulgaris). The measurements were made between daybreak and sunrise, and again during the middle of the afternoon on days when the potential evapotranspiration varied between 6.5 and 8.0 mm of water. The gradients varied from a maximum of 0.2 bar per cm in a wheat, down to an undetectable value for pumpkin. Although most of the soil in the root zone was kept at potentials above –1 bar, the bulk of the root tissue had water potentials of –5 to –10 bars. Differences in water potential between shaded and unshaded leaves, and between leaf tissue and guttation fluid suggested a similar drop of several bars between xylem elements and the surrounding leaf tissue in some plant species. The implications of such drops are discussed with respect to plant water transport equations and pressure cell potential measurements. [ABSTRACT FROM AUTHOR]

The article focuses on the lesson about the subject of corn as a geography topic for elementary students. The lesson discusses the growth of a corn plant as a type of grasses and grains with which it is compared to specimens of oats, wheat, and rye. The outline of the lesson and the suggested teaching methods on the topic are presented. In the treatment of the subject, children are expected to take up the study from a geographical point of view. They are supposed to work out the problem of corn production and conduct a survey of its importance in the United States.

Fermentation of several common cereal flours with six strains of oral streptococci showed that the quantities of titratable and volatile acids, and their proportions, varied according to the cereal and bacterial strain. [ABSTRACT FROM AUTHOR]

The article focuses on the effect diet had on the resorption of the Alveolar bone. It states a study of the cariogenic potential of rice, oats, wheat, and corn found that a diet containing ground whole oats resulted in abnormal development of the mandibular bones in laboratory rats. It mentions that the presence of gingival pockets were found in rats impacted with hair and food debris and on the resorption of alveolar bone by the molars.