The genetics of grain mold resistance in sorghum (Sorghum bicolor (L.) Moench) /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1991.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | Grain mold damages sorghum through actual loss in yield and reduction in quality and nutritional value of the grain. Fusarium moniliforme and Curvularia lunata are the most important fungi causing grain mold in humid areas throughout the world. Development of cultivars resistant to sorghum grain mold should be based on knowledge of the genetics of the disease resistance. This research was designed to contribute to the present knowledge regarding gene-effect associations between known genes controlling pericarp color, plant color, presence or absence of a pigmented testa, and thickness of the mesocarp, and the effect that they may have in conferring grain mold resistance. Work was conducted using five inbred lines as a base population. Crosses were made to generate F1, F2, and backcross populations at College Station, beginning winter of 1988. Grain mold evaluation was conducted at College Station, Texas in 1990, and in Serere and Namulonge, in Uganda in 1991. Presence of a pigmented testa (B1-B2-), red pericarp color (RRYY), purple plant color (P-Q-), thin mesocarp (ZZ) and intensifier gene (II) are all dominantly inherited. The presence of a pigmented testa was the single most important character conferring grain mold resistance. Red pericarp color also confers grain mold resistance, although not as strongly a pigmented testa. The effect of red pericarp color in conferring resistance is enhanced when the intensifier gene is present. Mesocarp thickness was found to have no significant role in grain mold resistance. Tan plant color improves grain mold resistance, purple plant color does not. Presence of the intensifier gene in the grain improves resistance to grain mold with either purple or tan plant color. Grain mold resistance attributed to a pigmented testa, red pericarp color and intensifier gene are dominantly inherited. Grain mold resistance due to plant color is recessively inherited. College Station and Serere were not significantly different, and could provide good locations for grain mold resistance selection. Namulonge is not a suitable location. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Plant Pathology." |
| Physical Description: | xiii, 139 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |