Modifying lignin content and composition are targets to improve bioenergy crops for cellulosic conversion to biofuels. In sorghum and other C4 grasses, the brown midrib mutants have been shown to reduce lignin content and alter its composition. Bmr12 encodes the sorghum caffeic O-methyltransferase, which catalyzes the penultimate step in monolignol biosynthesis. From an EMS-mutagenized TILLING population, four bmr12 mutants were isolated. DNA sequencing identified the four missense mutations in the Bmr12 coding region, which changed evolutionarily conserved amino acids Ala71Val, Pro150Leu, Gly225Asp, and Gly325Ser. The previously characterized bmr12 mutants all contain premature stop codons. These newly identified mutants, along with the previously characterized bmr12-ref, represent the first allelic series of bmr12 mutants available in the same genetic background. The impacts of these newly identified mutations on protein accumulation, enzyme activity, Klason lignin content, lignin subunit composition, and saccharification yield were determined. Gly225Asp mutant greatly reduced protein accumulation, and Pro150Leu and Gly325Ser greatly impaired enzyme activity compared to wild type (WT). All four mutants significantly reduced Klason lignin content and altered lignin composition resulting in a significantly reduced S/G ratio relative to WT, but the overall impact of these mutations was less severe than bmr12-ref. Except for Gly325Ser, which is a hypomorphic mutant, all mutants increased the saccharification yield relative to WT. These mutants represent new tools to decrease lignin content and S/G ratio, possibly leading toward the ability to tailor lignin content and composition in the bioenergy grass sorghum. Keywords Brown midrib. bmr12. Caffeic O-methyltransferase (COMT). Lignin. Sorghum The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual's income is derived from any public assistance program (not all prohibited bases apply to all programs). Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.

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Inheritance of fruit-related traits was studied in a population generated by crossing two heirloom pepper (Capsicum annuum) cultivars, Round of Hungary and Bulgarian carrot. Inheritance of corrugated pericarp phenotype of ‘Round of Hungary’ behaved as a recessive trait controlled by two genes while round fruit shape behaved as a single gene. Pungent cultivar Bulgarian carrot had significantly higher total soluble solids, titratable acidity, antioxidant activities, and significantly thinner pericarp than fruit of Round of Hungary. Pericarp thickness was related to differences in both cell number and cell size. Analyses of F2 fruit indicated that fruit weight was positively correlated (P < 0.01) to fruit width and pericarp thickness. Fruit width was negatively correlated (P < 0.01) to fruit length and total soluble solids and positively correlated (P < 0.01) to pericarp thickness. Yellow color was negatively correlated (P < 0.05) to total soluble solids. Fruit length showed high inbreeding depression and transgressive segregation. Color measurements showed that yellow was correlated to lightness, and the relationships between red and yellow color spaces and carotenoid composition were complex.