Microscopy of the mature and developing caryopsis of Sorghum bicolor (L.) Moench.
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1984.
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| Subjects: | |
| Online Access: | Link to ProQuest Copy Link to OAKTrust copy |
| Abstract: | Bright field, polarizing, fluorescence and scanning electron microscopies were used to study the mature and developing sorghum caryopsis. Samples were three sorghum varieties with varying genetic characteristics. Autofluorescence, attributed mainly to ferulic acid in other cereals, was observed in all cell walls of sorghum. Calcofluor and Congo red, specific for mixed linkage (beta)-glucans, produced a fluorescent reaction in sorghum cell walls. Acid fuchsin, Orange G and ANS (8-anilino-1-naphthalene sulfonic acid) were used to locate proteins in the mature sorghum kernel. Nile Blue A reacted with the lipids in the aleurone and scutellum causing a bright yellow fluorescence. The cuticular layers were stained with Nile Blue A or a sudan dye. Diphenylborinic acid, a fluorochrome used for locating flavonoids in chromatography, caused fluorescence in the aleurone cell walls. Periodic acid/Schiff's reagent was used to produce fluorescence in starch. Phytin granules were observed only in the scutellum after treating with acriflavine-HCl. Treatment of sections with cyanogen bromide and p-aminobenzoic acid or barbituric acid produced intense fluorescence in nicotinic acid inclusions in the aleurone and scutellum. All four microscopy techniques were used to study the developing caryopsis. Starch granules were present in the ovary wall at anthesis and throughout development. The mature pericarp of SCO103-12 was brown. Pigmentation appeared in the epicarp cells between 22 and 26 days past anthesis. At anthesis, two of the sorghum varieties contained pigmented material in the inner integument cells. These two varieties (a Group II and a Group III sorghum) accumulated pigmented material believed to be tannin in the inner integument cells until a continuous pigmented layer resulted. The mechanism of deposition appeared different between the two types. The group II sorghum developed small vesicles throughout the cell and deposited the material until the layer appeared solid. In the Group III sorghum the vesicles accumulated around the cell walls and deposited the pigmented material into the cell forming vacuoles which eventually filled leaving a continuous pigmented layer. Endosperm starch, protein matrix, and protein body formation occurred simultaneously. There were differences among the three varieties in age at which specific kernel changes occurred. |
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| Item Description: | "Major subject: Food Science and Technology." Typescript (photocopy). Vita. |
| Physical Description: | xi, 100 leaves : color illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 84-89). |