Harold M. Sell

The fruit-setting factor from the ethanol extracts of immature corn kernels.

Abstract The fruit-setting factor of the ethanol extract of immature kernels of sweet corn ( Zea Mays rugosa , var. Golden Cross ) has been identified as the ethyl ester of 3-indole acetic acid. This ester is approximately 100 times more effective than is 3-indole acetic acid in inducing parthenocarpy in the tomato.

The carbohydrates in alfalfa Medicago sativa. I. General composition, identification of a nonreducing sugar and investigation of the pectic substances☆☆☆

Abstract Analysis of first- and second-cutting alfalfa (above-ground portion of the plant, leaves, stems, and flower heads) and alfalfa holocellulose is reported. Appreciable differences were found between the chemical composition of the first and second cuttings of alfalfa. The solubility of the hemicelluloses of alfalfa and alfalfa holocellulose in various concentrations of potassium hydroxide was determined. A nonreducing sugar was isolated from alfalfa and identified as sucrose. Pectic substances present in alfalfa were isolated and characterized. X-ray diffraction data are given.

The relative content of gibberellin in seedlings of gynoecious and monoecious cucumber (cucumis sativus)

Abstract Gibberellin A1 was isolated and identified from etiolated monoecious cucumber seedlings using paper, TLC and G-LC and bioassayed by utilizing dwarf pea, cucumber epicotyl, dwarf corn d1 and d5 plants. The gynoecious line, in which external application of GA3 accelerated staminate flower formation, contained less GA1. GA1 is possibly required for staminate flower formation in the monoecious, but not in the gynoecious line.

The synthesis and physiological activity of several α-alkylindole-3-acetic acids☆

Abstract The effect of α-alkylation on the physiological activity of indole-3-acetic acid was determined by the synthesis of α-methyl-, α-ethyl-, α-propyl- and α-isopropyl-IAA and assessing their relative activity in the promotion of parthenocarpic tomato ovary growth. Avena coleoptile elongation, and buckwheat root elongation. Indole was condensed with the appropriate 2-hydroxyalkanoic acid in the presence of potassium hydroxide in a high pressure autoclave at 240–260° for 15–21 hr. Both α-methyl-IAA and α-ethyl-IAA were significantly more active in promoting parthenocarpic tomato ovary growth than IAA. α-Propyl-IAA was of intermediate activity and a-isopropyl-IAA had the same activity as IAA. In the Avena assay α-methyl-IAA and α-ethyl-IAA were equal in activity to IAA. Substitution of an α-hydrogen with a propyl group reduced the activity below that of IAA while substitution with the larger isopropyl group further significantly reduced biological activity. With the exception of α-isopropyl IAA, the activity in the buckwheat assay followed the same pattern as with the Avena. IAA, α-methyl-IAA, and α-ethyl-IAA all gave responses indicative of strong auxins while the response of α-propyl-IAA was typical of a weak auxin. α-Isopropyl-IAA showed neither inhibition nor stimulation of buckwheat root elongation.

The occurrence of higher fatty acids in corn pollen

SummaryThe methyl esters of the fatty acids of corn pollen were prepared and fractionated through a Stedman column. Palmitic, stearic, oleic, linoleic, and linolenic acids were identified by the melting points of thep-bromophenacyl esters of the saturated acids and the hydroxy and bromine addition compounds of the unsaturated acids.

Inhibition of selected plant systems by stereoisomers of chloramphenicol

Abstract The stereospecificity of chloramphenicol isomers on the inhibition of several plant systems was investigated. l - Threo , d - erythro , l - erythro and the antibiotic d - threo -chloramphenicol were effective inhibitors of auxin-induced elongation, 14 C-leucine uptake and 14 C-leucine incorporation into the protein fraction of coleoptiles from Avena sativa and Triticum vulgare . The isomers also inhibited Avena coleoptile uptake of 14 C-α-aminoisobutyric acid and the de novo synthesis of α-amylase by aleurone layers from Hordeum vulgare seeds. All four compounds inhibited these processes to about the same extent and over a similar high concentration range (5 × 10 −4 to 5 × 10 −3 M). Bioassay of extracts from Avena coleoptiles treated with the non-antibiotic isomers revealed no tissue conversion into d - threo -chloramphenicol.

The synthesis and biological activity of several ethyl 1-acylindole-3-acetates

Abstract Several ethyl 1-acylindole-3-acetates have been synthesized and their biological activities in three plant systems ascertained. The 1-dichloroacetyl derivative was as active as the parent ester in the tomato ovary growth assay. The 2-chloropropionyl, 3-chloropropionyl, 4-nitrobenzoyl, and 4-aminobenzoyl derivatives were least active. The acetyl and chloroacetyl derivatives were of intermediate activity. The dichloroacetyl radical increased the activity of the parent ester as measured by delay in abscission of debladed bean petioles. The acetyl, chloroacetyl, and nitrobenzoyl compounds were less active, but more active than the parent compound. The 2-chloropropionyl, 3-chloropropionyl, and 4-aminobenzoyl derivatives were no more active than the parent ester and acid. All of the 1-acyl derivatives, except the acetyl, were as active in the Avena straight growth assay as both indole-3-acetic acid and ethyl indole-3-acetate over the range of concentrations used. Ethyl 1-acetylindole-3-acetate was of equivalent activity only at 1 × 10 −5 M. The possible implications of these results in the concepts of structural requirements for auxin activity are discussed.

Gougerotin—an inhibitor of protein synthesis and auxin-induced elongation in plants

Abstract Gougerotin, an aminoacyl nucleoside antibacterial substance, has been shown to be an effective inhibitor of auxin-induced elongation and protein synthesis in Avena coleoptiles.

Effect of Derivatives of L-Cysteine on the Growth of Leuconostoc mesenteroides P-60.

Summary 1. Alliin and L-cystine disulfoxide stimulated the growth of Leuconostoc mesenteroides but to a lesser degree than L-cystine. 2. Substitution of the sulfur hydrogen of L-cysteine by alkyl and alkene radicals did not produce any observable response. The sulfoxide of S-ethyl-L-cysteine was also inactive; however, S-propyl-L-cysteine sulfoxide was found to have a very slight activity. 3. The activity of alliin may be due to both the presence of the sulfoxide group and the unsaturation in the allyl radical.

A study of the lipid constituents of bird's-foot trefoil (L. corniculatus)☆

Abstract The neutral and other non-acidic lipids of birds-foot trefoil, Lotus corniculatus , have been isolated and identified. Among them are sterol esters, fatty acid methyl esters, triglycerides, free fatty acids and diglycerides. The fatty acids of these lipids along with the fatty acids from the total phospholipid fraction have been analyzed and a comparison made of the first and second harvest.