Details

Autor(en) / Beteiligte

• Fritz, J. O.
• Cantrell, R. P.
• Lechtenberg, V. L.
• Axtell, J. D.
• Hertel, J. M.

Titel

Brown Midrib Mutants in Sudangrass and Grain Sorghum1

Ist Teil von

• Crop science, 1981-09, Vol.21 (5), p.706-709

Ort / Verlag

Crop Science Society of America

Erscheinungsjahr

1981

Beschreibungen/Notizen

• Three low lignin, brown midrib (bmr) sorghum (Sorghum bicolor L. Moench) mutants, designated bmr‐6, bmr‐12, and bmr‐18, were each backcrossed to normal grain‐ and grassy‐type sorghums. The objective was to determine if the effect of the brown midrib mutants on fiber composition would be expressed equally in both grain‐ and grassy‐type genetic backgrounds. Analysis for fiber composition and in vitro dry matter disappearance (IVDMD) was conducted on mature stem tissue of mutant and normal plants from the F2 generation Of the first and second backcross. The bmr‐6 mutant reduced lignin percentage from 10.3 to 8.5 (P < 0.01) and increased IVDMD percentage from 39.6 to 48.7 (P < 0.01). Mutant ✕ background and mutant backcross interactions were not significant (P > 0.10), indicating that the effect of the bmr‐6 mutant was expressed as well in grassy‐type as in grain‐type backgrounds. Similar results were obtained with the bmr‐12 and bmr‐18 mutants. These mutants, evaluated after only one backcross, reduced stem lignin from 8.3 to 6.1% (P < 0.01) and increased IVDMD from 44.0 to 55.5% (P < 0.01). The effects were expressed as well in grassy‐type as in grain‐type backgrounds. Results indicate that sudangrass sorghums containing brown midrib mutant genes are lower in lignin percentage and higher in digestibility than normal genotypes. Mutant sudangrasses of this nature should be higher in digestible energy percentage and should result in greater animal production than normal sudangrasses [Sorghum sudanense (Piper) Stapf] when fed to ruminant animals.